1
|
Chai MG, Roberts JA, Kelly CF, Ungerer JPJ, McWhinney BC, Lipman J, Farkas A, Cotta MO. Efficiency of dosing software using Bayesian forecasting in achieving target antibiotic exposures in critically ill patients, a prospective cohort study. Anaesth Crit Care Pain Med 2023; 42:101296. [PMID: 37579945 DOI: 10.1016/j.accpm.2023.101296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/28/2023] [Accepted: 08/06/2023] [Indexed: 08/16/2023]
Abstract
INTRODUCTION Broad-spectrum antibiotics such as beta-lactams and vancomycin are frequently used to treat critically ill patients, however, a significant number do not achieve target exposures. Therapeutic drug monitoring (TDM) combined with Bayesian forecasting dosing software may improve target attainment in these patients. This study aims to describe the efficiency of dosing software for achieving target exposures of selected beta-lactam antibiotics and vancomycin in critically ill patients. METHODS A prospective cohort study was undertaken in an adult intensive care unit (ICU). Patients prescribed vancomycin, piperacillin-tazobactam and meropenem were included if they exhibited a subtherapeutic or supratherapeutic exposure informed by TDM. The dosing software, ID-ODS™, was used to generate dosing recommendations which could be either accepted or rejected by the treating team. Repeat antibiotic TDM were requested to determine if target exposures were achieved. RESULTS Between March 2020 and December 2021, 70 were included in the analysis. Software recommendations were accepted for 56 patients (80%) with 50 having repeated antibiotic measurements. Forty-three of the 50 patients (86%) achieved target exposures after one software recommendation, with 3 of the remaining 7 patients achieving target exposures after 2. Forty-seven patients out of the 50 patients (94%) achieved the secondary outcome of clinical cure. There were no antibiotic exposure-related adverse events reported. CONCLUSION The use of TDM combined with Bayesian forecasting dosing software increases the efficiency for achieving target antibiotic exposures in the ICU. Clinical trials comparing this approach with other dosing strategies are required to further validate these findings.
Collapse
Affiliation(s)
- Ming G Chai
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia; Pharmacy Department, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia.
| | - Jason A Roberts
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia; Pharmacy Department, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia; Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Brisbane, QLD, Australia; Division of Anaesthesiology Critical Care Emergency and Pain Medicine, Nimes University Hospital, University of Montpellier, Nimes, France; Herston Infectious Diseases Institute (HeIDI), Metro North Health, Brisbane, Australia
| | - Christina F Kelly
- Pharmacy Department, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia
| | - Jacobus P J Ungerer
- Pathology Queensland, Brisbane, Australia; Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | | | - Jeffrey Lipman
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia; Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Brisbane, QLD, Australia
| | - Andras Farkas
- Optimum Dosing Strategies, Bloomingdale, NJ, United States
| | - Menino O Cotta
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
| |
Collapse
|
2
|
Smith EK, McWhinney BC. Stability of buffered benzylpenicillin and flucloxacillin for a paediatric outpatient parenteral antibiotic therapy service. J Pharm Pract Res 2021. [DOI: 10.1002/jppr.1746] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Brett C. McWhinney
- Analytical Chemistry Unit Department of Chemical Pathology Pathology Queensland RBWH Herston Australia
| |
Collapse
|
3
|
Allen DR, Warnholtz C, McWhinney BC. Investigation and Resolution of Interference in the LC-QTOF-MS Detection of 4-MePPP. J Anal Toxicol 2021; 46:bkaa199. [PMID: 33394037 DOI: 10.1093/jat/bkaa199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/10/2020] [Accepted: 01/03/2021] [Indexed: 11/14/2022] Open
Abstract
An interference resulting in the false-positive detection of the synthetic cathinone 4-MePPP in urine was suspected following the recent addition of 4-MePPP spectral data to an LC-QTOF-MS drug library. Although positive detection criteria were achieved, it was noted that all urine samples suspected of containing 4-MePPP also concurrently contained high levels of tramadol and its associated metabolites. Using QTOF-MS software elucidation tools, candidate compounds for the suspected interference were proposed. To provide further confidence in the identity of the interference, in silico fragmentation tools were used to match product ions generated in the analysis with product ions predicted from the theoretical fragmentation of candidate compounds. The ability of the suspected interference to subsequently produce the required product ions for spectral library identification of 4-MePPP was also tested. This information was used to provide a high preliminary confidence in the compound identity prior to purchase and subsequent confirmation with certified reference material. A co-eluting isobaric interference was identified and confirmed as an in-source fragment of the tramadol metabolite, N,N-bisdesmethyltramadol. Proposed resolutions for this interference are also described and subsequently validated by retrospective interrogation of previous cases of suspected interference.
Collapse
Affiliation(s)
- Darren R Allen
- Department of Chemical Pathology, Pathology Queensland Central Laboratory, Brisbane, Qld, 4006, Australia
| | - Christopher Warnholtz
- Department of Chemical Pathology, Pathology Queensland Central Laboratory, Brisbane, Qld, 4006, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland Central Laboratory, Brisbane, Qld, 4006, Australia
| |
Collapse
|
4
|
Scott JG, Baker A, Lim CCW, Foley S, Dark F, Gordon A, Ward D, Richardson D, Bruxner G, Beckmann KM, Hatherill S, Stathis S, Dixon K, Ryan AE, McWhinney BC, Ungerer JPJ, Berk M, Dean OM, Saha S, McGrath J. Effect of Sodium Benzoate vs Placebo Among Individuals With Early Psychosis: A Randomized Clinical Trial. JAMA Netw Open 2020; 3:e2024335. [PMID: 33170261 PMCID: PMC7656289 DOI: 10.1001/jamanetworkopen.2020.24335] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
IMPORTANCE There is evidence that sodium benzoate (BZ) may be an effective adjunctive treatment for schizophrenia. The clinical efficacy of BZ has been investigated in chronic schizophrenia; however, the efficacy of this agent has not been studied in individuals with early psychosis. OBJECTIVE To examine the clinical efficacy of the adjunctive use of BZ for symptoms in people with early psychosis. DESIGN, SETTING, AND PARTICIPANTS Using a placebo-controlled double-masked parallel-group design, this randomized clinical trial was conducted from August 2015 to July 2018. Participants aged between 15 and 45 years experiencing early psychosis were enrolled from 5 major clinical sites in Queensland, Australia. Data analysis was conducted from October 2018 to February 2020. INTERVENTIONS Participants were randomized 1:1 (50 participants in each group) to receive 500 mg of sodium benzoate twice daily or placebo for 12 weeks. MAIN OUTCOMES AND MEASURES The primary efficacy outcome was the Positive and Negative Syndrome Scale (PANSS) total score at 12 weeks. The key secondary efficacy measures were (1) the Clinical Global Impression score, (2) the Hamilton Depression Rating Scale for depression, (3) functioning as assessed by the clinician-rated Global Assessment of Function, and (4) the Assessment of Quality of Life Scale. The PANSS subscale scores and impact on selected amino acid concentrations were also assessed. RESULTS The study comprised 100 participants with a mean (SD) age of 21.4 (4.1) years, of whom 73 (73%) were male individuals. The mean (SD) baseline PANSS score was 75.3 (15.4). We found no improvement in total PANSS score in the BZ group compared with the placebo group. The end result of least-squares mean difference (SE) for total PANSS was -1.2 (2.4) (P = .63). There were no differences in any subscales of the PANSS, any secondary measures, nor any amino acid concentrations. The dose of BZ was well tolerated without any clinically significant treatment-emergent adverse event differences between BZ and placebo groups. CONCLUSIONS AND RELEVANCE In this randomized clinical trial, there was no evidence that adjunctive use of 500 mg of BZ twice daily is an effective treatment for individuals with early psychosis. TRIAL REGISTRATION anzctr.org.au Identifier: ACTRN12615000187549.
Collapse
Affiliation(s)
- James G. Scott
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia
- QIMR Berghofer Medical Research Institute, Herston, Australia
- Metro North Mental Health Service, Herston, Australia
| | - Andrea Baker
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia
| | - Carmen C. W. Lim
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia
- Queensland Brain Institute, University of Queensland, St Lucia, Australia
| | - Sharon Foley
- Emotional Health Unit, Mater Hospital, South Brisbane, Australia
| | | | - Anne Gordon
- Metro North Mental Health, Royal Brisbane and Women’s Hospital, Herston, Australia
| | - David Ward
- Metro North Mental Health, Royal Brisbane and Women’s Hospital, Herston, Australia
| | | | - George Bruxner
- Metro North Mental Health, Caboolture and Redcliffe Hospitals, Caboolture, Australia
| | - K. Martin Beckmann
- School of Medicine, Logan Hospital, Griffith University, Meadowbrook, Australia
- Child and Youth Mental Health Service, Metro South Mental Health, Logan Hospital, Meadowbrook, Australia
| | - Sean Hatherill
- Metro South Addiction and Mental Health Services, Logan Hospital, Meadowbrook, Australia
| | - Stephen Stathis
- Queensland Children’s Hospital, South Brisbane, Australia
- Child Health Research Centre, University of Queensland, Brisbane, Australia
| | - Krystal Dixon
- Mental Health and Addiction Services, Sunshine Coast Hospital and Health Service, Birtinya, Australia
- School of Medicine, Sunshine Coast University Hospital, Griffith University, Birtinya, Australia
| | - Alexander E. Ryan
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia
- QIMR Berghofer Medical Research Institute, Herston, Australia
- University of Queensland Centre for Clinical Research, Herston, Australia
| | - Brett C. McWhinney
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women’s Hospital, Herston, Australia
| | - Jacobus P. J. Ungerer
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Australia
- School of Biomedical Sciences, University of Queensland, St Lucia, Australia
| | - Michael Berk
- Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Deakin University, Geelong, Australia
| | - Olivia M. Dean
- Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Barwon Health, Deakin University, Geelong, Australia
| | - Sukanta Saha
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia
- Queensland Brain Institute, University of Queensland, St Lucia, Australia
| | - John McGrath
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia
- Queensland Brain Institute, University of Queensland, St Lucia, Australia
- National Centre for Register-based Research, Department of Economics and Business Economics, Aarhus University, Aarhus, Denmark
| |
Collapse
|
5
|
Guo Z, Poglitsch M, McWhinney BC, Ungerer JPJ, Ahmed AH, Gordon RD, Wolley M, Stowasser M. Measurement of Equilibrium Angiotensin II in the Diagnosis of Primary Aldosteronism. Clin Chem 2020; 66:483-492. [PMID: 32068832 DOI: 10.1093/clinchem/hvaa001] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 09/24/2019] [Indexed: 01/04/2023]
Abstract
BACKGROUND Many medications (including most antihypertensives) and physiological factors affect the aldosterone/renin ratio (ARR) when screening for primary aldosteronism (PA). We sought to validate a novel equilibrium angiotensin II (eqAngII) assay and compare correlations between the aldosterone/angiotensin II ratio (AA2R) and the current ARR under conditions affecting the renin-angiotensin system. METHODS Among 78 patients recruited, PA was excluded in 22 and confirmed in 56 by fludrocortisone suppression testing (FST). Peripheral levels of eqAngII, plasma renin activity (PRA) and direct renin concentration (DRC) were measured. RESULTS EqAngII showed good consistency with DRC and PRA independent of PA diagnosis, posture, and fludrocortisone administration. EqAngII showed close (P < 0.01) correlations with DRC (r = 0.691) and PRA (r = 0.754) during FST. DRC and PRA were below their assays' functional sensitivity in 43.9% and 15.1%, respectively, of the total 312 samples compared with only 7.4% for eqAngII (P < 0.01). Bland-Altman analysis revealed an overestimation of PRA and DRC compared with eqAngII in a subset of samples with low renin levels. The AA2R showed not only consistent changes with the ARR but also close (P < 0.01) correlations with the ARR, whether renin was measured by DRC (r = 0.878) or PRA (r = 0.880). CONCLUSIONS Dynamic changes of eqAngII and the AA2R show good consistency and close correlations with renin and the ARR. The eqAngII assay shows better sensitivity than DRC and PRA assays, especially at low concentrations. Whether the AA2R can reduce the impact of some factors that influence the diagnostic power of the ARR warrants further study.
Collapse
Affiliation(s)
- Zeng Guo
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | | | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Queensland, Australia
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Ashraf H Ahmed
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| |
Collapse
|
6
|
Aulin LBS, De Paepe P, Dhont E, de Jaeger A, Vande Walle J, Vandenberghe W, McWhinney BC, Ungerer JPJ, van Hasselt JGC, De Cock PAJG. Population Pharmacokinetics of Unbound and Total Teicoplanin in Critically Ill Pediatric Patients. Clin Pharmacokinet 2020; 60:353-363. [PMID: 33030704 DOI: 10.1007/s40262-020-00945-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Teicoplanin is a highly protein-bound antibiotic, increasingly used to treat serious Gram-positive infections in critically ill children. Maturational and pathophysiological intensive care unit-related changes often lead to altered pharmacokinetics. In this study, the objectives were to develop a pediatric population-pharmacokinetic model of unbound and total teicoplanin concentrations, to investigate the impact of plasma albumin levels and renal function on teicoplanin pharmacokinetics, and to evaluate the efficacy of the current weight-based dosing regimen. METHODS An observational pharmacokinetic study was performed and blood samples were collected for quantification of unbound and total concentrations of teicoplanin after the first dose and in assumed steady-state conditions. A population-pharmacokinetic analysis was conducted using a standard sequential approach and Monte Carlo simulations were performed for a probability of target attainment analysis using previously published pharmacokinetic-pharmacodynamic targets. RESULTS A two-compartment model with allometric scaling of pharmacokinetic parameters and non-linear plasma protein binding best described the data. Neither the inclusion of albumin nor the renal function significantly improved the model and no other covariates were supported for inclusion in the final model. The probability of target attainment analysis showed that the standard dosing regimen does not satisfactory attain the majority of the proposed targets. CONCLUSIONS We successfully characterized the pharmacokinetics of unbound and total teicoplanin in critically ill pediatric patients. The highly variable unbound fraction of teicoplanin could not be predicted using albumin levels, which may support the use of therapeutic drug monitoring of unbound concentrations. Poor target attainment was shown for the most commonly used dosing regimen, regardless of the pharmacokinetic-pharmacodynamic target evaluated.
Collapse
Affiliation(s)
- L B S Aulin
- Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - P De Paepe
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
| | - E Dhont
- Department of Pediatric Intensive Care, Ghent University Hospital, Ghent, Belgium
| | - A de Jaeger
- Department of Pediatric Intensive Care, Ghent University Hospital, Ghent, Belgium
| | - J Vande Walle
- Department of Pediatric Nephrology, Ghent University Hospital, Ghent, Belgium
| | - W Vandenberghe
- Department of Pediatric Intensive Care, Ghent University Hospital, Ghent, Belgium
| | - B C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Brisbane, QLD, Australia
| | - J P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Brisbane, QLD, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - J G C van Hasselt
- Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - P A J G De Cock
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium. .,Department of Pediatric Intensive Care, Ghent University Hospital, Ghent, Belgium. .,Department of Pharmacy, Ghent University Hospital, De Pintelaan 185, 9000, Ghent, Belgium.
| |
Collapse
|
7
|
Guo Z, Nanba K, Udager A, McWhinney BC, Ungerer JPJ, Wolley M, Thuzar M, Gordon RD, Rainey WE, Stowasser M. Biochemical, Histopathological, and Genetic Characterization of Posture-Responsive and Unresponsive APAs. J Clin Endocrinol Metab 2020; 105:5855173. [PMID: 32516371 PMCID: PMC7426003 DOI: 10.1210/clinem/dgaa367] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 06/05/2020] [Indexed: 01/27/2023]
Abstract
CONTEXT AND OBJECTIVE Posture-responsive and posture-unresponsive aldosterone-producing adenomas (APAs) account for approximately 40% and 60% of APAs, respectively. Somatic gene mutations have been recently reported to exist in approximately 90% of APAs. This study was designed to characterize the biochemical, histopathologic, and genetic properties of these 2 types of APA. METHODS Plasma levels of aldosterone and hybrid steroids (18-oxocortisol and 18-hydroxycortisol) were measured by liquid chromatography-tandem mass spectrometry. Immunohistochemistry for CYP11B2 (aldosterone synthase) and CYP17A1 (17α-hydroxylase) and deoxyribonucleic acid sequencing (Sanger and next-generation sequencing) were performed on APA tissue collected from 23 posture-unresponsive and 17 posture-responsive APA patients. RESULTS Patients with posture-unresponsive APA displayed higher (P < 0.01) levels of hybrid steroids, recumbent aldosterone and cortisol, larger (P < 0.01) zona fasciculata (ZF)-like tumors with higher (P < 0.01) expression of CYP17A1 (but not of CYP11B2) than patients with posture-responsive APA (most of which were not ZF-like). Of 40 studied APAs, 37 (92.5%) were found to harbor aldosterone-driving somatic mutations (KCNJ5 = 14 [35.0%], CACNA1D = 13 [32.5%], ATP1A1 = 8 [20.0%], and ATP2B3 = 2 [5.0%]), including 5 previously unreported mutations (3 in CACNA1D and 2 in ATP1A1). Notably, 64.7% (11/17) of posture-responsive APAs carried CACNA1D mutations, whereas 56.5% (13/23) of posture-unresponsive APAs harbored KCNJ5 mutations. CONCLUSIONS The elevated production of hybrid steroids by posture-unresponsive APAs may relate to their ZF-like tumor cell composition, resulting in expression of CYP17A1 (in addition to somatic gene mutation-driven CYP11B2 expression), thereby allowing production of cortisol, which acts as the substrate for CYP11B2-generated hybrid steroids.
Collapse
Affiliation(s)
- Zeng Guo
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Kazutaka Nanba
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, US
- Department of Endocrinology and Metabolism, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
| | - Aaron Udager
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, US
- Michigan Center for Translational Pathology, Ann Arbor, MI, US
- Rogel Cancer Center, University of Michigan, Ann Arbor, MI, US
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia
- School of Biomedical Sciences, University of Queensland, Brisbane, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Moe Thuzar
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
- Department of Endocrinology, Princess Alexandra Hospital, Brisbane, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - William E Rainey
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, US
- Division of Metabolism, Endocrine, and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, US
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
- Correspondence and Reprint Requests: Professor Michael Stowasser (MBBS, FRACP, PhD), Hypertension Unit, Princess Alexandra Hospital, 199 Ipswich Road, Woolloongabba, Brisbane, Queensland, 4102, Australia. E-mail:
| |
Collapse
|
8
|
Ranganathan D, Abdul-Aziz MH, John GT, McWhinney BC, Fassett RG, Healy H, Kubler P, Lim A, Lipman J, Purvey M, Roberts M, Reyaldeen R, Ungerer J, Roberts JA. Pharmacokinetics of Enteric-Coated Mycophenolate Sodium in Lupus Nephritis (POEMSLUN). Ther Drug Monit 2020; 41:703-713. [PMID: 31219949 PMCID: PMC6867677 DOI: 10.1097/ftd.0000000000000658] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Mycophenolate mofetil or enteric-coated mycophenolate sodium (EC-MPS) and steroids are used for induction and maintenance therapy in severe lupus nephritis. Blood concentrations of mycophenolic acid (MPA), the active metabolite of these drugs, vary among patients with lupus nephritis. The objective of this study was to examine whether concentration-controlled (CC) dosing (through therapeutic drug monitoring) of EC-MPS results in a higher proportion of participants achieving target exposure of MPA compared with fixed-dosing (FD). An additional aim of the study was to evaluate the influence of CC dosing on clinical outcomes. METHODS Nineteen participants were randomly assigned either to the FD or CC group. All the participants were eligible to have free and total measurements of MPA over a period of 8-12 hours on 3 different occasions. Area under the concentration-time curve between 0 and 12 hours (AUC0-12) was calculated using noncompartmental methods. Dose of EC-MPS was titrated according to AUC0-12 in the CC group. RESULTS Thirty-two AUC0-12 measurements were obtained from 9 FD and 9 CC participants. Large inter-patient variability was observed in both groups but was more pronounced in the FD group. There were no significant differences between FD and CC participants in any pharmacokinetic parameters across the study visits, except for total C0 (FD 2.0 ± 0.3 mg/L versus CC 1.1 ± 0.3; P = 0.01) and dose-normalized C0 (FD 2.9 ± 0.2 mg/L/g versus CC 2.1 ± 0.7 mg/L/g; P = 0.04) at the second visit and total AUC0-12 (FD 66.6 ± 6.0 mg·h/L versus CC 35.2 ± 11.4 mg·h/L; P = 0.03) at the third visit. At the first study visit, 33.3% of the FD and 11.1% of the CC participants achieved the target area under the concentration-time curve (P = 0.58). From the second visit, none of the FD participants, compared with all the CC participants, achieved target AUC0-12 (P = 0.01). More CC participants achieved remission compared with FD participants (absolute difference of -22.2, 95% confidence interval (Equation is included in full-text article.)0.19 to 0.55; P = 0.62). The mean free MPA AUC0-12 was significantly lower in those who had complete remission. CONCLUSIONS CC participants reached target AUC0-12 quicker. Larger studies are required to test clinical efficacy.
Collapse
Affiliation(s)
- Dwarakanathan Ranganathan
- Department of Renal Medicine, Royal Brisbane and Women's Hospital.,School of Medicine, Griffith University
| | - Mohd H Abdul-Aziz
- Faculty of Medicine, University of Queensland Centre for Clinical Research (UQCCR), The University of Queensland
| | - George T John
- Department of Renal Medicine, Royal Brisbane and Women's Hospital
| | | | - Robert G Fassett
- Faculty of Medicine, University of Queensland Centre for Clinical Research (UQCCR), The University of Queensland
| | - Helen Healy
- Department of Renal Medicine, Royal Brisbane and Women's Hospital.,Faculty of Medicine, University of Queensland Centre for Clinical Research (UQCCR), The University of Queensland
| | | | - Aaron Lim
- Department of Renal Medicine, Royal Brisbane and Women's Hospital
| | - Jeffrey Lipman
- Intensive Care Medicine, Royal Brisbane and Women's Hospital
| | - Megan Purvey
- Department of Renal Medicine, Royal Brisbane and Women's Hospital
| | - Matthew Roberts
- Department of Renal Medicine, Royal Brisbane and Women's Hospital
| | - Reza Reyaldeen
- Department of Renal Medicine, Royal Brisbane and Women's Hospital
| | | | - Jason A Roberts
- Faculty of Medicine, University of Queensland Centre for Clinical Research (UQCCR), The University of Queensland.,Intensive Care Medicine, Royal Brisbane and Women's Hospital.,Pharmacy Department, Royal Brisbane and Women's Hospital.,Centre for Translational Anti-Infective Pharmacodynamics, School of Pharmacy, The University of Queensland, Queensland, Australia
| |
Collapse
|
9
|
Smith EK, Shergold JA, McWhinney BC. Compatibility of intravenous busulfan with BBraun giving sets, fludarabine and Posiflush. J Pharm Pract Res 2020. [DOI: 10.1002/jppr.1598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Evonne K. Smith
- Pharmacy Department, Queensland Children’s Hospital Brisbane Australia
| | - Jill A. Shergold
- Blood and Marrow Service, Oncology Services, Queensland Children's Hospital Brisbane Australia
| | - Brett C. McWhinney
- Analytical Chemistry Unit, Department of Chemical Pathology Pathology Queensland, Royal Brisbane and Women’s Hospital Brisbane Australia
| |
Collapse
|
10
|
Guo Z, Poglitsch M, Cowley D, Domenig O, McWhinney BC, Ungerer JPJ, Wolley M, Stowasser M. Effects of Ramipril on the Aldosterone/Renin Ratio and the Aldosterone/Angiotensin II Ratio in Patients With Primary Aldosteronism. Hypertension 2020; 76:488-496. [PMID: 32507039 DOI: 10.1161/hypertensionaha.120.14871] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The aldosterone/renin ratio (ARR) is currently considered the most reliable approach for case detection of primary aldosteronism (PA). ACE (Angiotensin-converting enzyme) inhibitors are known to raise renin and lower aldosterone levels, thereby causing false-negative ARR results. Because ACE inhibitors lower angiotensin II levels, we hypothesized that the aldosterone/equilibrium angiotensin II (eqAngII) ratio (AA2R) would remain elevated in PA. Receiver operating characteristic curve analysis involving 60 patients with PA and 40 patients without PA revealed that the AA2R was not inferior to the ARR in screening for PA. When using liquid chromatography-tandem mass spectrometry to measure plasma aldosterone concentration, the predicted optimal AA2R cutoff for PA screening was 8.3 (pmol/L)/(pmol/L). We then compared the diagnostic performance of the AA2R with the ARR among 25 patients with PA administered ramipril (5 mg/day) for 2 weeks. Compared with basally, plasma levels of equilibrium angiotensin I (eqAngI) and direct renin concentration increased significantly (P<0.01 or P<0.05) after ramipril treatment, whereas eqAngII and ACE activity (eqAngII/eqAngI) decreased significantly (P<0.01). The changes of plasma renin activity and plasma aldosterone concentration in the current study were not significant. On day 14, 4 patients displayed false-negative results using ARR_direct renin concentration (plasma aldosterone concentration/direct renin concentration), 3 of whom also showed false-negative ARR_plasma renin activity (plasma aldosterone concentration/plasma renin activity). On day 15, 2 patients still demonstrated false-negative ARR_plasma renin activity, one of whom also showed a false-negative ARR_direct renin concentration. No false-negative AA2R results were observed on either day 14 or 15. In conclusion, compared with ARR which can be affected by ACE inhibitors causing false-negative screening results, the AA2R seems to be superior in detecting PA among subjects receiving ACE inhibitors.
Collapse
Affiliation(s)
- Zeng Guo
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| | | | - Diane Cowley
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| | - Oliver Domenig
- Attoquant Diagnostics GmbH, Vienna, Austria (M.P., O.D.)
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia (B.C.M., J.P.J.U.)
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia (B.C.M., J.P.J.U.).,School of Biomedical Sciences, University of Queensland, Brisbane, Australia (J.P.J.U.)
| | - Martin Wolley
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| | - Michael Stowasser
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| |
Collapse
|
11
|
Thuzar M, Young K, Ahmed AH, Ward G, Wolley M, Guo Z, Gordon RD, McWhinney BC, Ungerer JP, Stowasser M. Diagnosis of Primary Aldosteronism by Seated Saline Suppression Test-Variability Between Immunoassay and HPLC-MS/MS. J Clin Endocrinol Metab 2020; 105:5611084. [PMID: 31676899 DOI: 10.1210/clinem/dgz150] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 10/30/2019] [Indexed: 02/04/2023]
Abstract
BACKGROUND In primary aldosteronism (PA), excessive, autonomous secretion of aldosterone is not suppressed by salt loading or fludrocortisone. For seated saline suppression testing (SSST), the recommended diagnostic cutoff 4-hour plasma aldosterone concentration (PAC) measured by high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS is 162 pmol/L. Most diagnostic laboratories, however, use immunoassays to measure PAC. The cutoff for SSST using immunoassay is not known. We hypothesized that the cutoff is different between the assays. METHODS We analyzed 80 of the 87 SSST tests that were performed during our recent study defining the HPLC-MS/MS cutoff. PA was confirmed in 65 by positive fludrocortisone suppression testing (FST) and/or lateralization on adrenal venous sampling and excluded in 15 by negative FST. PAC was measured by a chemiluminescence immunoassay (PACIA) in the SSST samples using the DiaSorin Liaison XL analyzer, and receiver operating characteristics (ROC) analysis was performed to identify the PACIA cutoff. RESULTS ROC revealed good performance (area under the curve = 0.893; P < .001) of 4-hour postsaline PACIA for diagnosis of PA and an optimal diagnostic cutoff of 171 pmol/L, with sensitivity and specificity of 95.4% and 80.0%, respectively. A higher cutoff of 217 pmol/L improved specificity (86.7%) with lower sensitivity (86.2%). PACIA measurements strongly correlated with PAC measured by HPLC-MS (r = 0.94, P < .001). CONCLUSIONS A higher diagnostic cutoff for SSST should be employed when PAC is measured by immunoassay rather than HPLC-MS/MS. The results suggest that (i) PA can be excluded if 4-hour PACIA is less than 171 pmol/L, and (ii) PA is highly likely if the PACIA is greater than 217 pmol/L by chemiluminescence immunoassay. A gray zone exists between the cutoffs of 171 and 217 pmol/L, likely reflecting a lower specificity of immunoassay.
Collapse
Affiliation(s)
- Moe Thuzar
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Australia
- Department of Endocrinology, Princess Alexandra Hospital, Brisbane, Australia
| | - Karen Young
- Department of Chemical Pathology, Sullivan Nicolaides Laboratories, Brisbane, Australia
| | - Ashraf H Ahmed
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Australia
| | - Greg Ward
- Department of Chemical Pathology, Sullivan Nicolaides Laboratories, Brisbane, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Australia
| | - Zeng Guo
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Australia
| | - Jacobus P Ungerer
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Australia
- Faculty of Biomedical Science, University of Queensland, Brisbane, Australia
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Australia
| |
Collapse
|
12
|
Lambert K, Bird L, Borst AC, Fuller A, Wang Y, Rogers GB, Stanford J, Sanderson-Smith ML, Williams JG, McWhinney BC, Neale EP, Probst Y, Lonergan M. Safety and Efficacy of Using Nuts to Improve Bowel Health in Hemodialysis Patients. J Ren Nutr 2020; 30:462-469. [PMID: 32001127 DOI: 10.1053/j.jrn.2019.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/23/2019] [Accepted: 10/04/2019] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Constipation is common in patients with end-stage kidney disease. Nondrug strategies to manage constipation are challenging because of dietary potassium, phosphate, and fluid restrictions. Nuts are a high-fiber food but are excluded from the diet because of the high potassium and phosphate content. The aim of this study was to examine the safety and efficacy of using nuts to improve constipation in adults undertaking hemodialysis (HD). DESIGN AND METHODS Adult patients undertaking HD were recruited to this nonrandomized, 10-week repeated measures, within-subject, pragmatic clinical trial, conducted in two HD units. The intervention consisted of consumption of 40g of raw almonds daily for four weeks, followed by a two-week washout and four-week control period. The primary safety outcome measures were change in predialysis serum potassium and phosphate levels. The primary efficacy outcome was reduction in constipation, measured using the Bristol Stool Form Scale and Palliative Care Outcome Scale (POS-S) renal symptom score. Secondary outcomes included quality of life, selected uremic toxins, cognition, gut microbiota profile, and symptom burden. RESULTS Twenty patients completed the trial (median age: 67 [interquartile range: 57.5-77.8] years, 51% male). After controlling for dialysis adequacy, anuria, dietary intake, bicarbonate, and parathyroid hormone, there were no statistically significant changes in serum potassium (P = 0.21) or phosphate (P = 0.16) associated with daily consumption of almonds. However, statistically significant improvements in constipation were seen at weeks 2, 3, 4, and 10. There were statistically significant improvements in quality of life (P = 0.030), overall symptom burden (P = 0.002), vomiting (P = 0.020), itching (P = 0.006), and skin changes (P = 0.002). CONCLUSION Daily consumption of almonds for four weeks was safe, effective, and well tolerated. Improvements in quality of life and symptom burden warrant further research to elucidate potential mechanisms. The findings support the potential reinclusion of foods such as nuts into the diet of patients who underwent HD.
Collapse
Affiliation(s)
- Kelly Lambert
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia; Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia; Illawarra Shoalhaven Local Health District, Wollongong, New South Wales, Australia.
| | - Luke Bird
- Illawarra Shoalhaven Local Health District, Wollongong, New South Wales, Australia
| | - Addison C Borst
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia
| | - Andrew Fuller
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia
| | - Yanan Wang
- Microbiome and Host Health Programme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Geraint B Rogers
- Microbiome and Host Health Programme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Jordan Stanford
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia
| | - Martina L Sanderson-Smith
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia; School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia
| | - Jonathan G Williams
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia; School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Queensland, Australia
| | - Elizabeth P Neale
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia; Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia
| | - Yasmine Probst
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia; Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia
| | - Maureen Lonergan
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales, Australia; Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia; Illawarra Shoalhaven Local Health District, Wollongong, New South Wales, Australia
| |
Collapse
|
13
|
Duke ME, Britten FL, Pretorius CJ, McWhinney BC, Ungerer JPJ, Barrett HL, Donovan P. Maternal Metyrapone Use During Breastfeeding: Safe for the Breastfed Infant. J Endocr Soc 2019; 3:973-978. [PMID: 31041428 PMCID: PMC6486806 DOI: 10.1210/js.2018-00355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/12/2019] [Indexed: 11/19/2022] Open
Abstract
Context Metyrapone is an inhibitor of endogenous adrenal corticosteroid synthesis, which has been proven to be a viable option in controlling maternal serum cortisol concentrations during pregnancy. The infant exposure to maternally ingested metyrapone through breast milk is, however, largely unknown. Case Description We report the excretion of metyrapone into breast milk and subsequent infant exposure from a lactating woman on 250 mg of metyrapone three times daily. Due to limited supply of breast milk, the infant was fed ∼50% breast milk and 50% formula. At steady state, the average concentrations in the studied breast milk and absolute and relative infant doses were 176 µg/L, 26.45 µg/kg/d, and 0.7%, respectively, for metyrapone, and 310 µg/L, 46.52 µg/kg/d, and 1.21% for its active metabolite metyrapol. The breastfed infant was found to have a plasma metyrapone concentration of 0.05 µg/L, with no evidence of disruption to his adrenocortical axis biochemically. Conclusion These findings indicate that maternal metyrapone use during breastfeeding did not pose a notable risk to this breastfed infant. The infants’ exposure to metyrapone was further minimized by avoiding nursing for 2 to 3 hours after each metyrapone dose.
Collapse
Affiliation(s)
- Madeline E Duke
- Department of Obstetric Medicine, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
| | - Fiona L Britten
- Department of Obstetric Medicine, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
| | - Carel J Pretorius
- Department of Chemical Pathology, Pathology Queensland, Herston, Queensland, Australia.,University of Queensland, Faculty of Medicine, Queensland, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Herston, Queensland, Australia
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Herston, Queensland, Australia.,University of Queensland, Faculty of Medicine, Queensland, Australia
| | - Helen L Barrett
- Department of Obstetric Medicine, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
| | - Peter Donovan
- University of Queensland, Faculty of Medicine, Queensland, Australia.,Department of Clinical Pharmacology, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
| |
Collapse
|
14
|
Guo Z, Poglitsch M, McWhinney BC, Ungerer JPJ, Ahmed AH, Gordon RD, Wolley M, Stowasser M. Aldosterone LC-MS/MS Assay-Specific Threshold Values in Screening and Confirmatory Testing for Primary Aldosteronism. J Clin Endocrinol Metab 2018; 103:3965-3973. [PMID: 30137438 DOI: 10.1210/jc.2018-01041] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 08/15/2018] [Indexed: 02/13/2023]
Abstract
CONTEXT Current threshold values for primary aldosteronism (PA) diagnostic testing are based on measuring aldosterone (PAC) using immunoassays. Quantification of PAC by liquid chromatography-tandem mass spectrometry (LC-MS/MS) yields lower values. OBJECTIVE To compare aldosterone measurement by radioimmunoassay (RIA) with LC-MS/MS and evaluate performances of proposed LC-MS/MS-specific cutoffs for PA screening and confirmatory testing. PATIENTS AND INTERVENTION Forty-one patients underwent aldosterone/renin ratio (ARR) testing to screen for, and fludrocortisone suppression testing (FST) to confirm or exclude, PA. Renin (DRC) was measured by chemiluminescent immunoassay. RESULTS Median serum PACLC-MS/MS was 27.8% lower (P < 0.05) than plasma PACRIA in 164 pairs of FST samples. A positive correlation (Spearman coefficient, 0.894, P < 0.01; Pearson r coefficient, 0.861, P < 0.01) was observed between the two assays. Thirty-seven patients showed consistent FST diagnoses (29 positive, 8 negative), whereas four showed inconsistent FSTs by the two assays. Good agreement (κ coefficient, 0.736; P < 0.01) was observed between the current FST diagnostic PACRIA cutoff of 165 pmol/L and the proposed PACLC-MS/MS cutoff of 133 pmol/L. Among 37 patients with consistent FST results, no differences were observed in sensitivity (89.7% vs 93.1%) or specificity (87.5% vs 87.5%) for PA screening between the current ARR cutoff of 70 pmol/mU (PACRIA/DRC) and the proposed cutoff of 55 pmol/mU (PACLC-MS/MS/DRC). CONCLUSIONS Adjustment of the current cutoffs for PA diagnostic testing is necessary if PAC is measured by LC-MS/MS. Our preliminary results suggest that the proposed LC-MS/MS cutoffs for ARR and FST perform as well as current RIA cutoffs.
Collapse
Affiliation(s)
- Zeng Guo
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | | | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Queensland, Australia
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Ashraf H Ahmed
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Queensland, Australia
| |
Collapse
|
15
|
Stowasser M, Ahmed AH, Cowley D, Wolley M, Guo Z, McWhinney BC, Ungerer JP, Gordon RD. Comparison of Seated With Recumbent Saline Suppression Testing for the Diagnosis of Primary Aldosteronism. J Clin Endocrinol Metab 2018; 103:4113-4124. [PMID: 30239841 DOI: 10.1210/jc.2018-01394] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 09/13/2018] [Indexed: 02/13/2023]
Abstract
CONTEXT Failure of plasma aldosterone suppression during fludrocortisone suppression testing (FST) or saline suppression testing (SST) confirms primary aldosteronism (PA). Aldosterone is often higher upright than recumbent in PA; upright levels are used during FST. In a pilot study (24 patients with PA), seated saline suppression testing (SSST) was more sensitive than recumbent saline suppression testing (RSST). OBJECTIVE, DESIGN, AND PATIENTS The current validation study involved 100 patients who underwent FST, RSST, and SSST, eight before and after unilateral adrenalectomy. Of the 108 FSTs, 73 confirmed and 18 excluded PA. Four patients with inconclusive FST lateralized on adrenal venous sampling, making a total of 77 with PA. RESULTS The area under the receiver operating characteristic (ROC) curve was greater for SSST than RSST (0.96 vs. 0.80; P < 0.01). ROC analysis predicted optimal cutoff aldosterone levels of 162 pmol/L for SSST and 106 pmol/L for RSST. At these cutoffs, SSST showed high sensitivity for PA (87%) that markedly exceeded that for RSST (38%; P < 0.001) but similar specificity (94 vs. 94%; not significant). SSST was more sensitive than RSST in detecting both unilateral (n = 28, 93% vs. 68%, P < 0.05) and bilateral (n = 40, 85% vs. 20%, P < 0.001) forms of PA. Only three SSST (vs. 9 RSST and 17 FST) results were inconclusive. CONCLUSIONS SSST is highly sensitive and superior to RSST in identifying both unilateral and bilateral forms of PA and has a low rate of false positives and inconclusive results. It therefore offers a reliable and much less complicated and expensive alternative to FST for confirming PA.
Collapse
Affiliation(s)
- Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Ashraf H Ahmed
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Diane Cowley
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Zeng Guo
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia
| | - Jacobus P Ungerer
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia
| |
Collapse
|
16
|
Rawlins M, Cheng V, Raby E, Dyer J, Regli A, Ingram P, McWhinney BC, Ungerer JPJ, Roberts JA. Pharmacokinetics of Ceftolozane-Tazobactam during Prolonged Intermittent Renal Replacement Therapy. Chemotherapy 2018; 63:203-206. [PMID: 30304718 DOI: 10.1159/000493196] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 08/24/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Prolonged intermittent renal replacement therapy (PIRRT) eliminates many drugs, and without dosing data, for new antibiotics like ceftolozane/tazobactam, suboptimal concentrations and treatment failure are likely. OBJECTIVES Herein, we describe the effect of PIRRT on the plasma pharmacokinetics of ceftolozane/tazobactam ad-ministered in a critically ill 55-year-old patient with a polymicrobial sternal wound osteomyelitis, including a multiresistant Pseudomonas aeruginosa. METHOD Blood samples were taken over 4 days where the patient received a 7.5-h PIRRT treatment. One- and 2-compartment models were tested for ceftolozane and tazobactam separately, and the log-likelihood ratio and goodness-of-fit plots were used to select the final model. RESULTS Two-compartment models were developed for ceftolozane and tazobactam separately and described significant differences in clearance of ceftolozane and tazobactam with and without PIRRT (8.273 vs. 0.393 and 8.020 vs. 0.767 L/h, respectively). CONCLUSIONS A ceftolozane/tazobactam dose of 500 mg/250 mg appears to be sufficient to attain pharmacokinetic/pharmacodynamic targets during PIRRT while the manufacturer's recommended dosing of 100 mg/50 mg every 8 h was sufficient during non-PIRRT periods.
Collapse
Affiliation(s)
- Matthew Rawlins
- Department of Pharmacy, Fiona Stanley Hospital, Perth, Washington, Australia
| | - Vesa Cheng
- University of Queensland Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Edward Raby
- Department of Infectious Diseases, Fiona Stanley Hospital, Perth, Washington, Australia
| | - John Dyer
- Department of Infectious Diseases, Fiona Stanley Hospital, Perth, Washington, Australia
| | - Adrian Regli
- Department of Intensive Care Medicine, Fiona Stanley Hospital, Perth, Washington, Australia
| | - Paul Ingram
- Department of Infectious Diseases, Fiona Stanley Hospital, Perth, Washington, Australia
| | - Brett C McWhinney
- Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Jacobus P J Ungerer
- University of Queensland Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia.,Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Jason A Roberts
- University of Queensland Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, .,Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, .,Pharmacy Department, Royal Brisbane and Womens' Hospital, Brisbane, Queensland, .,Centre for Translational Anti-Infective Pharmacodynamics, School of Pharmacy, The University of Queensland, Brisbane, Queensland,
| |
Collapse
|
17
|
Md Dom ZI, Coller JK, Carroll RP, Tuke J, McWhinney BC, Somogyi AA, Sallustio BC. Mycophenolic acid concentrations in peripheral blood mononuclear cells are associated with the incidence of rejection in renal transplant recipients. Br J Clin Pharmacol 2018; 84:2433-2442. [PMID: 29974488 DOI: 10.1111/bcp.13704] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/22/2018] [Accepted: 06/24/2018] [Indexed: 11/28/2022] Open
Abstract
AIMS Although therapeutic drug monitoring of plasma mycophenolic acid (MPA) concentrations has been recommended to individualize dosage in transplant recipients, little is known regarding lymphocyte concentrations of MPA, where MPA inhibits inosine monophosphate dehydrogenase (IMPDH). This study investigated the utility of measuring predose MPA concentrations in peripheral blood mononuclear cells (C0C ) and predose IMPDH activity, as predictors of graft rejection in renal transplant recipients. METHODS Forty-eight patients commencing mycophenolate mofetil (1 g twice daily) in combination with tacrolimus and prednisolone were recruited. Blood was collected for determination of trough total (C0P ) and unbound (C0u ) plasma MPA concentrations. Peripheral blood mononuclear cells were isolated for determination of C0C and IMPDH activity. The incidence of rejection within 2 days of sample collection was determined histologically and classified according to the Banff 2007 criteria. RESULTS There was no association between MPA C0C and C0P (rs = 0.28, P = 0.06), however, MPA C0C were weakly correlated with MPA C0u (rs = 0.42, P = 0.013). Multivariate analysis indicated that MPA C0C was the only covariate independently associated with rejection (FDR-adjusted P = 0.033). The receiver operating characteristic area under the curve (AUC) for the prediction of severe rejection using MPA C0C was 0.75 (P = 0.013), with 73% sensitivity and specificity at a C0C threshold of 0.5 ng 10-7 cells. However, predose IMPDH activity was not a predictor of rejection (P > 0.15). CONCLUSIONS MPA C0C measurement within the early post-transplant period may be useful to facilitate early titration of MPA dosing to significantly reduce rejection.
Collapse
Affiliation(s)
- Zaipul I Md Dom
- Discipline of Pharmacology, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia.,Department of Clinical Pharmacology, The Queen Elizabeth Hospital, Woodville, SA, 5011, Australia
| | - Janet K Coller
- Discipline of Pharmacology, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Robert P Carroll
- Centre for Clinical and Experimental Transplantation, Central Northern Adelaide Renal and Transplantation Service, Royal Adelaide Hospital, Adelaide, SA, 5000, Australia
| | - Jonathan Tuke
- School of Mathematical Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia.,ARC Centre of Excellence for Mathematical & Statistical Frontiers, School of Mathematical Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Andrew A Somogyi
- Discipline of Pharmacology, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia.,Department of Clinical Pharmacology, Royal Adelaide Hospital, Adelaide, SA, 5000, Australia
| | - Benedetta C Sallustio
- Discipline of Pharmacology, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia.,Department of Clinical Pharmacology, The Queen Elizabeth Hospital, Woodville, SA, 5011, Australia
| |
Collapse
|
18
|
Ahmed AH, Gordon RD, Ward G, Wolley M, McWhinney BC, Ungerer JP, Stowasser M. Effect of Combined Hormonal Replacement Therapy on the Aldosterone/Renin Ratio in Postmenopausal Women. J Clin Endocrinol Metab 2017; 102:2329-2334. [PMID: 28379474 DOI: 10.1210/jc.2016-3851] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 03/27/2017] [Indexed: 02/13/2023]
Abstract
BACKGROUND Plasma aldosterone/renin ratio (ARR) is the most popular screening test for primary aldosteronism (PA). Because both estrogen and progesterone (including in oral contraceptive agents) affect aldosterone and renin levels, we studied the effects of combined hormonal replacement therapy (HRT) on ARR; renin was measured as both direct renin concentration (DRC) and plasma renin activity (PRA). METHODS Fifteen normotensive, healthy postmenopausal women underwent measurement (seated, midmorning) of plasma aldosterone, DRC, PRA, electrolytes, and creatinine and urinary aldosterone, cortisol, electrolytes, and creatinine at baseline and after 2 weeks and 6 weeks of treatment with combined HRT (conjugated estrogens 0.625 mg and medroxyprogesterone 2.5 mg daily). RESULTS Combined HRT was associated with statistically significant increases in aldosterone [median (range): baseline, 150 (85 to 600); 2 weeks, 230 (129 to 790); 6 weeks, 434 (200 to 1200) pmol/L; P < 0.001 (Friedman test)] and PRA [2.3 (1.2 to 4.3), 3.8 (1.4 to 7.0), 5.1 (1.4 to 10.8) ng/mL/h, respectively; P < 0.001] but decreases in DRC [21 (10 to 31), 21 (10 to 39), and 14 (8.0 to 30) mU/L, respectively; P < 0.01], leading to increases in ARR calculated by DRC [7.8 (3.6 to 34.8), 11.4 (5.4 to 48.5), and 30.4 (10.5 to 90.2), respectively; P < 0.001]. The ARR calculated by DRC exceeded the cutoff value (70) in three patients after 6 weeks. There were no significant changes in ARR calculated by PRA [79 (26 to 184), 91 (23 to 166), and 88 (50 to 230), respectively; P = 0.282], plasma electrolytes and creatinine, or any urinary measurements. CONCLUSION The combined oral HRT used in this study is capable of significantly increasing ARR with a risk of false-positive results during screening for PA but only if DRC (and not PRA) is used to calculate the ratio.
Collapse
Affiliation(s)
- Ashraf H Ahmed
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| | - Gregory Ward
- Sullivan & Nicolaides Pathology, Brisbane 4068, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia
| | - Jacobus P Ungerer
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| |
Collapse
|
19
|
Ahmed AH, Gordon RD, Ward G, Wolley M, McWhinney BC, Ungerer JP, Stowasser M. Effect of Moxonidine on the Aldosterone/Renin Ratio in Healthy Male Volunteers. J Clin Endocrinol Metab 2017; 102:2039-2043. [PMID: 28324033 DOI: 10.1210/jc.2016-3821] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/10/2017] [Indexed: 11/19/2022]
Abstract
BACKGROUND The most popular screening test for primary aldosteronism is the plasma aldosterone/renin ratio (ARR). Medications, dietary sodium, posture, and time of day all affect renin and aldosterone levels and can result in false-negative or false-positive ARRs if not controlled. Most antihypertensive medications affect the ARR and can interfere with interpretation of results. To our knowledge, no study has been undertaken to evaluate the effects of moxonidine on the ARR. METHODS Normotensive, nonmedicated male volunteers (n = 20) underwent measurement (seated, midmorning) of plasma aldosterone (by high-performance liquid chromatography-tandem mass spectrometry), direct renin concentration (DRC), plasma renin activity (PRA), cortisol, electrolytes and creatinine; and urinary aldosterone, cortisol, electrolytes and creatinine at baseline and after 1 week of moxonidine at 0.2 mg/d and a further 5 weeks at 0.4 mg/d. RESULTS Compared with baseline, despite the expected significant falls in both systolic and diastolic blood pressure, levels of plasma aldosterone [median, 134 (range, 90 to 535) pmol/L], DRC [20 (10 to 37) mU/L], PRA [2.2 (1.0-3.8) ng/mL/h], and ARR using either DRC [8.0 (4.4 to 14.4)] or PRA [73 (36 to 218)] were not significantly changed after either 1 [135 (98-550) pmol/L, 20 (11-35) mU/L, 2.0 (1.2-4.1) ng/mL/h, 8.8 (4.2 to 15.9), and 73 (32-194), respectively] or 6 weeks [130 (90-500) pmol/L, 22 (8 to 40) mU/L, 2.1 (1.0 to 3.2) ng/mL/h, 7.7 (4.3 to 22.4), and 84 (32 to 192), respectively] of moxonidine. There were no changes in any urinary measurements. CONCLUSION Moxonidine was associated with no significant change in the ARR and may therefore be a good option for maintaining control of hypertension when screening for primary aldosteronism.
Collapse
Affiliation(s)
- Ashraf H Ahmed
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| | - Richard D Gordon
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| | - Gregory Ward
- Sullivan & Nicolaides Pathology, Brisbane 4068, Australia
| | - Martin Wolley
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia
| | - Jacobus P Ungerer
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane 4029, Australia
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia
| |
Collapse
|
20
|
De Cock PAJG, Mulla H, Desmet S, De Somer F, McWhinney BC, Ungerer JPJ, Moerman A, Commeyne S, Vande Walle J, Francois K, Van Hasselt JGC, De Paepe P. Population pharmacokinetics of cefazolin before, during and after cardiopulmonary bypass to optimize dosing regimens for children undergoing cardiac surgery. J Antimicrob Chemother 2016; 72:791-800. [DOI: 10.1093/jac/dkw496] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 10/17/2016] [Indexed: 02/03/2023] Open
|
21
|
|
22
|
Bergmann TK, Isbel NM, Ostini R, Barraclough KA, Campbell SB, McWhinney BC, Inder WJ, Russell A, Staatz CE. Exploratory study of total and free prednisolone plasma exposure and cushingoid appearance, quality of life and biochemical toxicity in adult male kidney transplant recipients. Clin Drug Investig 2016; 35:743-50. [PMID: 26403249 DOI: 10.1007/s40261-015-0334-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND OBJECTIVE Long-term adverse effects of oral glucocorticoids are frequent and serious. Large between-patient variability in the pharmacokinetics of prednisolone might explain why drug dose is a poor predictor of drug-related toxicity. The aim of the study was to investigate relationships between prednisolone exposure and adverse effects. METHODS Male kidney transplant recipients were recruited for serial blood sampling and assessment of glucocorticoid-related adverse effects including dyslipidaemia, abnormal body fat distribution, Cushingoid appearance and impaired quality of life. Total and free prednisolone plasma concentrations were determined using ultra-high-performance liquid chromatography with tandem mass spectrometric detection. Prednisolone exposure was estimated using a limited sampling strategy. RESULTS Fifty-six patients were recruited. Patients had a mean age of 54 years and median time post-transplantation of 75 months. Median prednisolone dose was 5 mg. Mean area under the plasma concentration-time curve was 2390 nmol h/L (±580) (SD) and 175 nmol h/L (±78) for total and free prednisolone, respectively. Waist to upper arm circumference ratio was positively associated with free prednisolone plasma exposure with a Spearman correlation coefficient of 0.30 (p value 0.02). The correlation coefficient was 0.24 (p value 0.08) for neck to upper arm circumference ratio and free prednisolone plasma exposure. The clinical Cushingoid phenotype as determined by the Visual Assessment of Cushing's Severity (VACS) score was associated with a reduced score relating to physical functioning on the SF-12, but there was no significant relationship between free prednisolone plasma exposure and quality-of-life scores. Lipid levels and haemoglobin A1c (HbA1c) were not associated with total or free prednisolone exposure. CONCLUSIONS There is a positive correlation between free prednisolone plasma exposure and waist to upper arm circumference ratio in adult male kidney transplant recipients on low maintenance prednisolone doses. There is no significant association between total or free prednisolone plasma exposure and plasma glucose and lipid levels in the low prednisolone dose range.
Collapse
Affiliation(s)
- Troels K Bergmann
- School of Pharmacy, University of Queensland, Brisbane, Australia. .,Department of Clinical Chemistry and Pharmacology, Odense University Hospital, J.B. Winsloews Vej 19, 5000, Odense C, Denmark.
| | - Nicole M Isbel
- Department of Nephrology, University of Queensland at the Princess Alexandra Hospital, Brisbane, Australia
| | - Remo Ostini
- Rural Clinical School Research Centre, University of Queensland, Toowoomba, Australia
| | | | - Scott B Campbell
- Department of Nephrology, University of Queensland at the Princess Alexandra Hospital, Brisbane, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane, Australia
| | - Warrick J Inder
- Department of Diabetes and Endocrinology, Princess Alexandra Hospital, Brisbane, Australia.,School of Medicine, The University of Queensland, Brisbane, Australia
| | - Anthony Russell
- Department of Diabetes and Endocrinology, Princess Alexandra Hospital, Brisbane, Australia.,School of Medicine, The University of Queensland, Brisbane, Australia
| | | |
Collapse
|
23
|
Rossi M, Johnson DW, Morrison M, Pascoe EM, Coombes JS, Forbes JM, Szeto CC, McWhinney BC, Ungerer JPJ, Campbell KL. Synbiotics Easing Renal Failure by Improving Gut Microbiology (SYNERGY): A Randomized Trial. Clin J Am Soc Nephrol 2016; 11:223-31. [PMID: 26772193 DOI: 10.2215/cjn.05240515] [Citation(s) in RCA: 222] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 11/02/2015] [Indexed: 01/19/2023]
Abstract
BACKGROUND AND OBJECTIVES The generation of key uremic nephrovascular toxins, indoxyl sulfate (IS), and p-cresyl sulfate (PCS), is attributed to the dysbiotic gut microbiota in CKD. The aim of our study was to evaluate whether synbiotic (pre- and probiotic) therapy alters the gut microbiota and reduces serum concentrations of microbiome-generated uremic toxins, IS and PCS, in patients with CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Predialysis adult participants with CKD (eGFR=10-30 ml/min per 1.73 m(2)) were recruited between January 5, 2013 and November 12, 2013 to a randomized, double-blind, placebo-controlled, crossover trial of synbiotic therapy over 6 weeks (4-week washout). The primary outcome was serum IS. Secondary outcomes included serum PCS, stool microbiota profile, eGFR, proteinuria-albuminuria, urinary kidney injury molecule-1, serum inflammatory biomarkers (IL-1β, IL-6, IL-10, and TNF-α), serum oxidative stress biomarkers (F2-isoprostanes and glutathione peroxidase), serum LPS, patient-reported health, Gastrointestinal Symptom Score, and dietary intake. A prespecified subgroup analysis explored the effect of antibiotic use on treatment effect. RESULTS Of 37 individuals randomized (age =69±10 years old; 57% men; eGFR=24±8 ml/min per 1.73 m(2)), 31 completed the study. Synbiotic therapy did not significantly reduce serum IS (-2 μmol/L; 95% confidence interval [95% CI], -5 to 1 μmol/L) but did significantly reduce serum PCS (-14 μmol/L; 95% CI, -27 to -2 μmol/L). Decreases in both PCS and IS concentrations were more pronounced in patients who did not receive antibiotics during the study (n=21; serum PCS, -25 μmol/L; 95% CI, -38 to -12 μmol/L; serum IS, -5 μmol/L; 95% CI, -8 to -1 μmol/L). Synbiotics also altered the stool microbiome, particularly with enrichment of Bifidobacterium and depletion of Ruminococcaceae. Except for an increase in albuminuria of 38 mg/24 h (P=0.03) in the synbiotic arm, no changes were observed in the other secondary outcomes. CONCLUSION In patients with CKD, synbiotics did not significantly reduce serum IS but did decrease serum PCS and favorably modified the stool microbiome. Large-scale clinical trials are justified.
Collapse
Affiliation(s)
- Megan Rossi
- School of Medicine, Translational Research Institute, Brisbane, Queensland, Australia; Nephrology Department, Princess Alexandra Hospital, Brisbane, Queensland, Australia;
| | - David W Johnson
- School of Medicine, Translational Research Institute, Brisbane, Queensland, Australia; Nephrology Department, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - Mark Morrison
- Translational Research Institute, Brisbane, Queensland, Australia; Diamantina Institute
| | | | | | - Josephine M Forbes
- School of Medicine, Translational Research Institute, Brisbane, Queensland, Australia; Mater Research Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Cheuk-Chun Szeto
- Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; and
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Queensland, Australia
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Queensland, Australia
| | - Katrina L Campbell
- School of Medicine, Translational Research Institute, Brisbane, Queensland, Australia; Nephrology Department, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| |
Collapse
|
24
|
Li H, Pham T, McWhinney BC, Ungerer JP, Pretorius CJ, Richard DJ, Mortimer RH, d'Emden MC, Richard K. Sex Hormone Binding Globulin Modifies Testosterone Action and Metabolism in Prostate Cancer Cells. Int J Endocrinol 2016; 2016:6437585. [PMID: 27990161 PMCID: PMC5136390 DOI: 10.1155/2016/6437585] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 10/10/2016] [Accepted: 10/20/2016] [Indexed: 11/18/2022] Open
Abstract
Sex Hormone Binding Globulin (SHBG) is the major serum carrier of sex hormones. However, growing evidence suggests that SHBG is internalised and plays a role in regulating intracellular hormone action. This study was to determine whether SHBG plays a role in testosterone uptake, metabolism, and action in the androgen sensitive LNCaP prostate cancer cell line. Internalisation of SHBG and testosterone, the effects of SHBG on testosterone uptake, metabolism, regulation of androgen responsive genes, and cell growth were assessed. LNCaP cells internalised SHBG by a testosterone independent process. Testosterone was rapidly taken up and effluxed as testosterone-glucuronide; however this effect was reduced by the presence of SHBG. Addition of SHBG, rather than reducing testosterone bioavailability, further increased testosterone-induced expression of prostate specific antigen and enhanced testosterone-induced reduction of androgen receptor mRNA expression. Following 38 hours of testosterone treatment cell morphology changed and growth declined; however, cotreatment with SHBG abrogated these inhibitory effects. These findings clearly demonstrate that internalised SHBG plays an important regulatory and intracellular role in modifying testosterone action and this has important implications for the role of SHBG in health and disease.
Collapse
Affiliation(s)
- Huika Li
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
| | - Thy Pham
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Brett C. McWhinney
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
| | - Jacobus P. Ungerer
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
| | - Carel J. Pretorius
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
| | - Derek J. Richard
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Robin H. Mortimer
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Michael C. d'Emden
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
- Department of Endocrinology and Diabetes, Royal Brisbane and Women's Hospital, Herston, QLD 4029, Australia
| | - Kerry Richard
- Conjoint Endocrine Laboratory, Chemical Pathology, Pathology Queensland, Queensland Health, Herston, QLD 4029, Australia
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
- *Kerry Richard:
| |
Collapse
|
25
|
Abd Rahman AN, Tett SE, Abdul Gafor HA, McWhinney BC, Staatz CE. Exposure-effect relationship of mycophenolic acid and prednisolone in adult patients with lupus nephritis. Br J Clin Pharmacol 2015; 80:1064-75. [PMID: 25959850 DOI: 10.1111/bcp.12678] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 04/20/2015] [Accepted: 05/01/2015] [Indexed: 01/12/2023] Open
Abstract
AIMS The aim was to examine relationships between total and unbound mycophenolic acid (MPA) and prednisolone exposure and clinical outcomes in patients with lupus nephritis. METHODS Six blood samples were drawn pre- and at 1, 2, 4, 6 and 8 h post-dose and total and unbound MPA and prednisolone pre-dose (C0 ), maximum concentration (Cmax ) and area under the concentration-time curve (AUC) were determined using non-compartmental analysis in 25 patients. The analyses evaluated drug exposures in relation to treatment response since starting MPA and drug-related adverse events. RESULTS Dose-normalized AUC varied 10-, 8-, 7- and 19-fold for total MPA, unbound MPA, total prednisolone and unbound prednisolone, respectively. Median values (95% CI) of total MPA AUC(0,8 h) (21.5 [15.0, 42.0] vs. 11.2 [4.8, 30.0] mg l(-1) h, P= 0.048) and Cmax (11.9 [6.7, 26.3] vs. 6.1 [1.6, 9.2] mg l(-1) , P = 0.016) were significantly higher in responders than non-responders. Anaemia was significantly associated with higher total (37.8 [14.1, 77.5] vs. 18.5 [11.7, 32.7] mg l(-1) h, P = 0.038) and unbound MPA AUC(0,12 h) (751 [214, 830] vs. 227 [151, 389] mg l(-1) h, P = 0.004). Unbound prednisolone AUC(0,24 h) was significantly higher in patients with Cushingoid appearance (unbound: 1372 [1242, 1774] vs. 846 [528, 1049] nmol l(-1) h, P = 0.019) than in those without. Poorer treatment response was observed in patients with lowest tertile exposure to both total MPA and prednisolone as compared with patients with middle and higher tertile exposure (17% vs. 74%, P = 0.023). CONCLUSIONS This study suggests a potential role for therapeutic drug monitoring in individualizing immunosuppressant therapy in patients with lupus nephritis.
Collapse
Affiliation(s)
- Azrin N Abd Rahman
- School of Pharmacy, University of Queensland, Brisbane, Queensland, Australia.,School of Pharmacy, International Islamic University of Malaysia, Kuantan, Pahang, Malaysia
| | - Susan E Tett
- School of Pharmacy, University of Queensland, Brisbane, Queensland, Australia
| | - Halim A Abdul Gafor
- Nephrology Unit, Department of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras, Kuala Lumpur, Malaysia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Christine E Staatz
- School of Pharmacy, University of Queensland, Brisbane, Queensland, Australia
| |
Collapse
|
26
|
Bergmann TK, Isbel NM, Barraclough KA, Campbell SB, McWhinney BC, Staatz CE. Comparison of the influence of cyclosporine and tacrolimus on the pharmacokinetics of prednisolone in adult male kidney transplant recipients. Clin Drug Investig 2014; 34:183-8. [PMID: 24385281 DOI: 10.1007/s40261-013-0162-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND OBJECTIVE Cyclosporine has been observed to precipitate cushingoid features in kidney transplant recipients already on prednisolone. Some pharmacokinetic studies have demonstrated increased prednisolone exposure in patients on cyclosporine therapy compared with azathioprine, whereas other studies have found no difference. The objective of this study was to determine whether cyclosporine impacts on prednisolone exposure as compared with tacrolimus. METHODS Adult male kidney transplant recipients treated with prednisolone and either cyclosporine or tacrolimus were recruited for pharmacokinetic blood sampling at the outpatient clinic at the Princess Alexandra Hospital, Brisbane, Australia. Prednisolone plasma concentrations were determined using ultra-high-performance liquid chromatography. Dose-adjusted area under the plasma concentration-time curve (AUC) of free and total prednisolone was estimated using a previously developed limited sampling strategy and non-compartmental analysis. RESULTS A total of 55 patients were eligible for analysis; 38 % received cyclosporine and 62 % received tacrolimus co-therapy. No significant difference in mean dose-adjusted total prednisolone AUC from 0 to 6 h post-dose or mean dose-adjusted free prednisolone AUC from 0 to 12 h was observed between the cyclosporine and tacrolimus groups (449 versus 428 nmol·h/L/mg, p = 0.43, and 32 versus 30 nmol·h/L/mg, p = 0.51, respectively). CONCLUSION Cyclosporine does not change the dose-adjusted exposure of prednisolone compared with tacrolimus. Adult kidney transplant recipients can therefore continue on their usual prednisolone dose when changing therapy between cyclosporine and tacrolimus.
Collapse
|
27
|
McDougall DAJ, McWhinney BC. Stability of Buffered Benzylpenicillin Solutions for Outpatient Parenteral Antimicrobial Therapy. Journal of Pharmacy Practice and Research 2014. [DOI: 10.1002/j.2055-2335.2014.tb00012.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- David AJ McDougall
- Pharmacy Department and Infection Management Services; Princess Alexandra Hospital
| | | |
Collapse
|
28
|
Brown NJ, Kimble RM, Rodger S, Ware RS, McWhinney BC, Ungerer JP, Cuttle L. Biological markers of stress in pediatric acute burn injury. Burns 2014; 40:887-95. [DOI: 10.1016/j.burns.2013.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 12/03/2013] [Accepted: 12/04/2013] [Indexed: 11/26/2022]
|
29
|
Rossi M, Johnson DW, Morrison M, Pascoe E, Coombes JS, Forbes JM, McWhinney BC, Ungerer JPJ, Dimeski G, Campbell KL. SYNbiotics Easing Renal failure by improving Gut microbiologY (SYNERGY): a protocol of placebo-controlled randomised cross-over trial. BMC Nephrol 2014; 15:106. [PMID: 24996842 PMCID: PMC4094543 DOI: 10.1186/1471-2369-15-106] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/30/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Emerging evidence suggests modulating the microbiota in the large bowel of patients with chronic kidney disease (CKD) through pre- and/probiotic supplementation may inhibit the development of key nephrovascular toxins. To date, quality intervention trials investigating this novel treatment in CKD are lacking. The aim of SYNERGY is to assess the effectiveness of synbiotics (co-administration of pre- and probiotics) as a potential treatment targeting the synthesis of uremic toxins, specifically, indoxyl sulphate (IS) and p-cresyl sulphate (PCS). METHODS/DESIGN Thirty-seven patients with moderate to severe CKD (Stage IV and V, pre-dialysis) will be recruited to a double-blind, placebo-controlled, randomised cross-over trial. Patients will be provided with synbiotic therapy or placebo for 6 weeks, with a 4 week washout before cross-over. The primary outcome is serum IS, total and free (unbound) concentrations, measured using ultra-performance liquid chromatography. Secondary outcomes include serum PCS, total and free (unbound) concentrations; cardiovascular risk, measured by serum lipopolysaccharides, serum trimethylamine-N-oxide (TMAO) and inflammation and oxidative stress markers; kidney damage, measured by 24 hour proteinuria and albuminuria, estimated glomerular filtration rate and renal tubule damage (urinary kidney injury molecule-1); patients' self assessed quality of life; and gastrointestinal symptoms. In addition, the effects on the community structure of the stool microbiota will be explored in a subset of patients to validate the mechanistic rationale underpinning the synbiotic therapy. DISCUSSION IS and PCS are two novel uremic toxins implicated in both cardiovascular disease (CVD) and progression of CKD. Preliminary studies indicate that synbiotic therapy maybe a promising strategy when considering a targeted, tolerable and cost-efficient therapy for lowering serum IS and PCS concentrations. This trial will provide high quality 'proof-of-concept' data to elucidate both the efficacy of synbiotic therapy for lowering the toxins and whether reductions in serum IS and PCS translate into clinical benefits. Considering the potential of pre- and probiotics to not only shift toxin levels, but to also impede CVD and CKD progression, SYNERGY will provide vital insight into the effectiveness of this innocuous nutritional therapy. TRIAL REGISTRATION Universal Trial Number: U1111-1142-4363. Australian New Zealand Clinical Trials Registry Number: ACTRN12613000493741, date registered: 2nd May 2013.
Collapse
Affiliation(s)
- Megan Rossi
- School of Medicine, University of Queensland, Brisbane, Australia
- Translational Research Institute, Brisbane, Australia
- Department of Nephrology, Princess Alexandra Hospital, Brisbane, Australia
| | - David W Johnson
- School of Medicine, University of Queensland, Brisbane, Australia
- Translational Research Institute, Brisbane, Australia
- Department of Nephrology, Princess Alexandra Hospital, Brisbane, Australia
| | - Mark Morrison
- Diamantina Institute, University of Queensland, Brisbane, Australia
- Translational Research Institute, Brisbane, Australia
| | - Elaine Pascoe
- School of Medicine, University of Queensland, Brisbane, Australia
| | - Jeff S Coombes
- Human Movement Studies, University of Queensland, Brisbane, Australia
| | - Josephine M Forbes
- Translational Research Institute, Brisbane, Australia
- Mater Medical Research Institute, Brisbane, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Australia
| | - Jacobus PJ Ungerer
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Australia
| | - Goce Dimeski
- School of Medicine, University of Queensland, Brisbane, Australia
- Chemical Pathology, Princess Alexandra Hospital, Brisbane, Australia
| | - Katrina L Campbell
- School of Medicine, University of Queensland, Brisbane, Australia
- Translational Research Institute, Brisbane, Australia
- Department of Nephrology, Princess Alexandra Hospital, Brisbane, Australia
| |
Collapse
|
30
|
Fagan KJ, Irvine KM, McWhinney BC, Fletcher LM, Horsfall LU, Johnson L, O'Rourke P, Martin J, Scott I, Pretorius CJ, Ungerer JPJ, Powell EE. Diagnostic sensitivity of carbohydrate deficient transferrin in heavy drinkers. BMC Gastroenterol 2014; 14:97. [PMID: 24885510 PMCID: PMC4042141 DOI: 10.1186/1471-230x-14-97] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 05/14/2014] [Indexed: 12/27/2022] Open
Abstract
Background and Aim Carbohydrate deficient transferrin (CDT) is the most specific serum biomarker of heavy alcohol consumption, defined as ≥ 350–420 g alcohol/week. Despite introduction of a standardized reference measurement technique, widespread use of CDT remains limited due to low sensitivity. The aim of this study was to determine the factors that affect diagnostic sensitivity in patients with sustained heavy alcohol intake. Methods Patients with a self-reported history of sustained heavy alcohol consumption were recruited from the hepatology outpatient department or medical wards. Each patient was interviewed with a validated structured questionnaire of alcohol consumption and CDT analysis using the standardized reference measurement technique with high performance liquid chromatography was performed on serum collected at time of interview. Results 52 patients were recruited: 19 from the hepatology outpatient department and 33 from general medical wards. Median alcohol intake was 1013 (range 366–5880) g/week over the preceding two week period. 26 patients had a diagnostic CDT based on a threshold value of %CDT > 1.7 indicating heavy alcohol consumption, yielding a sensitivity of 50%. Overweight/obesity (defined as body mass index (BMI) ≥ 25 kg/m2 in Caucasians and ≥ 23.0 kg/m2 in Asians), female gender and presence of cirrhosis were independently associated with non-diagnostic %CDT (≤ 1.7). Conclusions CDT has limited sensitivity as a biomarker of heavy alcohol consumption. Caution should be applied when ordering and interpreting %CDT results, particularly in women, patients with cirrhosis and those with an elevated BMI.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Elizabeth E Powell
- Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Woolloongabba 4102, Brisbane, Queensland, Australia.
| |
Collapse
|
31
|
Ranganathan D, John GT, Healy H, Roberts MJ, Fassett RG, Lipman J, Kubler P, Ungerer J, McWhinney BC, Lim A, Purvey M, Reyaldeen R, Roberts JA. A Protocol for the Pharmacokinetics of Enteric Coated Mycophenolate Sodium in Lupus Nephritis (POEMSLUN): an open-label, randomised controlled trial. BMJ Open 2013; 3:bmjopen-2013-003511. [PMID: 23929919 PMCID: PMC3740249 DOI: 10.1136/bmjopen-2013-003511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
INTRODUCTION Mycophenolate sodium, an enteric-coated tablet (EC-MPS), is as effective and safe as mycophenolate mofetil (MMF) in preventing transplant rejection. EC-MPS and MMF improve the outcome of severe lupus nephritis (LN) and have fewer side effects than pulsed intravenous cyclophosphamide. Blood concentrations of mycophenolic acid (MPA), the active metabolite of EC-MPS, vary between participants despite fixed dosing. Interpatient variability has been studied in transplantation, but not well documented in LN. The relationship between MPA concentration and its clinical effect on LN has not been described. METHODS AND ANALYSIS This is a prospective, open-label, randomised controlled trial. -32 participants with LN who meet the inclusion and exclusion criteria will be randomised into two groups: one receiving a fixed dose of EC-MPS and the second, a dosing regimen that is titrated with therapeutic drug monitoring. Included participants will have blood sampled over a period of 8-12 h on three different occasions. Pharmacokinetic parameters will be calculated using non-compartmental methods. ETHICS AND DISSEMINATION The Human Research and Ethics Committee of the Royal Brisbane Women's Hospital have approved this study. The study is registered with Australian and New Zealand Clinical Trials Registry-ACTRN12611000798965 We planned to present the de-identified information at conferences and publish the results in medical journals. TRIAL REGISTRATION ACTRN12611000798965.
Collapse
Affiliation(s)
| | - George T John
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Helen Healy
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Matthew J Roberts
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Robert G Fassett
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
- School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Jeffrey Lipman
- School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
- Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Paul Kubler
- Department of Clinical Pharmacology and Rheumatology, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Jacobus Ungerer
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Queensland, Australia
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Brisbane, Queensland, Australia
| | - Aaron Lim
- School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Megan Purvey
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Reza Reyaldeen
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Jason A Roberts
- School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
- Department of Pharmacy and Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| |
Collapse
|
32
|
Fagan KJ, Irvine KM, McWhinney BC, Fletcher LM, Horsfall LU, Johnson LA, Clouston AD, Jonsson JR, O'Rourke P, Martin J, Pretorius CJ, Ungerer JPJ, Powell EE. BMI but not stage or etiology of nonalcoholic liver disease affects the diagnostic utility of carbohydrate-deficient transferrin. Alcohol Clin Exp Res 2013; 37:1771-8. [PMID: 23875541 DOI: 10.1111/acer.12143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 03/02/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND A reliable biomarker is required in hepatology clinics for detection and follow-up of heavy alcohol consumption. Carbohydrate-deficient transferrin (CDT) increases with sustained heavy alcohol consumption and is the most specific biomarker of ethanol (EtOH) consumption. Recent introduction of a standardized method for measuring CDT has improved its clinical application. This study was designed to determine whether alcohol-independent factors influence CDT levels in patients with chronic liver disease (CLD). METHODS The relationship between serum %CDT and self-reported history of alcohol consumption was examined in 254 patients referred for evaluation of liver disease. CDT analysis was performed on serum collected at time of liver biopsy. RESULTS CDT levels were not affected by severity or etiology of nonalcoholic liver disease. Thirteen of 254 subjects had a %CDT >1.7, predictive of heavy alcohol intake, 6 of whom did not acknowledge heavy drinking. Twelve of these 13 subjects were suspected heavy drinkers on review of their medical records and clinical results. Conversely, not all acknowledged heavy drinkers had %CDT >1.7. Heavy drinkers with a body mass index (BMI) in the overweight or obese range had significantly lower %CDT than lean heavy drinkers. This persisted even when lean body weight was used as an approximation of the EtOH volume of distribution. CONCLUSIONS An elevated BMI reduces the diagnostic utility of CDT at higher alcohol intake in subjects with CLD using the standardized method. In a hepatology outpatient setting, this assay is likely to be useful to confirm suspicion of heavy drinking in subjects who are not overweight, but cannot reliably identify moderate drinkers or heavy drinkers who are overweight.
Collapse
Affiliation(s)
- Kevin J Fagan
- Department of Gastroenterology and Hepatology , Princess Alexandra Hospital, Brisbane, Queensland, Australia; Centre for Liver Disease Research , School of Medicine, Brisbane, Queensland, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Pretorius CJ, McWhinney BC, Sipinkoski B, Johnson LA, Rossi M, Campbell KL, Ungerer JP. Reference ranges and biological variation of free and total serum indoxyl- and p-cresyl sulphate measured with a rapid UPLC fluorescence detection method. Clin Chim Acta 2013; 419:122-6. [DOI: 10.1016/j.cca.2013.02.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 02/05/2013] [Accepted: 02/05/2013] [Indexed: 11/28/2022]
|
34
|
Oancea I, Png CW, Das I, Lourie R, Winkler IG, Eri R, Subramaniam N, Jinnah HA, McWhinney BC, Levesque JP, McGuckin MA, Duley JA, Florin THJ. A novel mouse model of veno-occlusive disease provides strategies to prevent thioguanine-induced hepatic toxicity. Gut 2013; 62:594-605. [PMID: 22773547 DOI: 10.1136/gutjnl-2012-302274] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE The anti-leukemic drugs, azathioprine and 6-mercaptopurine (6MP), are important in the treatment of inflammatory bowel disease but an alternative faster-acting, less-allergenic thiopurine, 6-thioguanine (6TG), can cause hepatic veno-occlusive disease/sinusoidal obstructive syndrome (SOS). Understanding of SOS has been hindered by inability to ethically perform serial liver biopsies on patients and the lack of an animal model. DESIGN Normal and C57Bl/6 mice with specific genes altered to elucidate mechanisms responsible for 6TG-SOS, were gavaged daily for upto 28d with 6TG, 6MP or methylated metabolites. Animal survival was monitored and at sacrifice a histological score of SOS, haematology and liver biochemistry were measured. RESULTS Only 6TG caused SOS, which was dose related. 6TG and to a lesser extent 6MP but not methylated metabolites were associated with dose-dependent haematopoietic toxicity. SOS was not detected with non-lethal doses of 6TG. SOS did not occur in hypoxanthine-phosphoribosyl transferase-deficient C57Bl/6 mice, demonstrating that 6TG-SOS requires thioguanine nucleotides. Hepatic inflammation was characteristic of SOS, and C57Bl/6 mice deficient in P- and E-selectins on the surface of vascular endothelial cells showed markedly reduced SOS, demonstrating a major role for leukocytes recruited from blood. Split dosing of 6TG markedly attenuated SOS but still effected immunosuppression and prevented spontaneous colitis in Winnie mice, which have a single nucleotide polymorphism mutation in Muc2. CONCLUSION This novel model provides clinically relevant insights into how 6TG induces SOS, and how this dangerous adverse drug reaction may be avoided by either inhibition of endothelial activation or simple changes to dosing regimens of 6TG, while still being effective treatment for colitis.
Collapse
Affiliation(s)
- Iulia Oancea
- IBD Team, Immunology Infection Inflammation Program, Mater Medical Research Institute, South Brisbane, Queensland, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Semark AJ, Venkatesh K, McWhinney BC, Pretorius C, Roberts JA, Cohen J, Venkatesh B. The compatibility of a low concentration of hydrocortisone sodium succinate with selected drugs during a simulated Y-site administration. CRIT CARE RESUSC 2013; 15:63-66. [PMID: 23432505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVES Bolus dose concentrations of hydrocortisone (50mg/mL) are reported to be incompatible with midazolam and ciprofloxacin in Y-site mixing studies. We evaluated the physical and chemical compatibility of low concentrations of hydrocortisone sodium succinate (1 mg/ mL) with midazolam (1 mg/mL and 2mg/mL) and ciprofloxacin (2 mg/mL) solutions during a simulated Y-site administration study. METHODS The midazolam 1mg/mL, midazolam 2mg/mL and ciprofloxacin 2mg/mL solutions were individually combined with hydrocortisone sodium succinate 1mg/mL solution in a 1:1 ratio and tested in triplicate. Physical compatibility was evaluated using a previously described method immediately on mixing, after 60 minutes and after 120 minutes. Chemical compatibility was determined by measuring the hydrocortisone sodium succinate concentration of the test solutions 120 minutes after mixing compared with that of a reference sample of hydrocortisone sodium succinate solution. RESULTS At all time points, when hydrocortisone was mixed with midazolam (1 mg/mL and 2mg/mL) and ciprofloxacin (2 mg/mL), the solutions remained clear, with no haziness, colour change, gas or precipitate formation, thus showing total physical compatibility. There were pharmacologically significant reductions (>10%) in measured hydrocortisone concentration (18.6% with midazolam 2mg/mL, P = 0.06; and 21.3% with ciprofloxacin, P = 0.01) in all of the test samples, as compared with the reference sample. CONCLUSIONS According to currently recommended criteria, combining hydrocortisone sodium succinate at a concentration of 1mg/mL with a 1mg/mL solution of midazolam appears to be both chemically and physically compatible. However, mixing 1mg/mL hydrocortisone sodium succinate with 2mg/mL midazolam or with 2mg/ mL ciprofloxacin cannot be recommended.
Collapse
Affiliation(s)
- Andrew J Semark
- Department of Intensive Care Medicine, Princess Alexandra Hospital, Brisbane, QLD, Australia.
| | | | | | | | | | | | | |
Collapse
|
36
|
Briscoe SE, McWhinney BC, Lipman J, Roberts JA, Ungerer JPJ. A method for determining the free (unbound) concentration of ten beta-lactam antibiotics in human plasma using high performance liquid chromatography with ultraviolet detection. J Chromatogr B Analyt Technol Biomed Life Sci 2012; 907:178-84. [PMID: 23026224 DOI: 10.1016/j.jchromb.2012.09.016] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Revised: 09/07/2012] [Accepted: 09/08/2012] [Indexed: 10/27/2022]
Abstract
With the clinical imperative to further research in the area of optimising antibiotic dosing in the intensive care setting, a simple high performance liquid chromatography method was developed and validated for routinely determining the free (unbound) concentration of ten beta-lactam antibiotics in 200 μL of human plasma. Antibiotics determined include three cephalosporins (ceftriaxone, cephazolin and cephalotin); two carbapenems (meropenem and ertapenem); and five penicillins (ampicillin, piperacillin, benzylpenicillin, flucloxacillin and dicloxacillin). There was a single common sample preparation method involving ultracentrifugation and stabilisation. Chromatography was performed on a Waters XBridge C18 column with, depending on analytes, one of four acetonitrile-phosphate buffered mobile phases. Peaks of interest were detected via ultraviolet absorbance at 210, 260 and 304 nm. The method has been validated and used in a pathology laboratory for therapeutic drug monitoring in critically ill patients. The significant variability in the level of protein binding that is common with antibiotics traditionally considered to have high protein binding (e.g. ceftriaxone, cephazolin, ertapenem, flucloxacillin and dicloxacillin) suggests that this assay should be preferred for measuring the pharmacologically active concentration of beta-lactam antibiotics in a therapeutic drug monitoring programme.
Collapse
Affiliation(s)
- Scott E Briscoe
- Chemical Pathology, Pathology Queensland, Brisbane, Queensland, Australia.
| | | | | | | | | |
Collapse
|
37
|
Barraclough KA, Staatz CE, Johnson DW, Lee KJ, McWhinney BC, Ungerer JPJ, Hawley CM, Campbell SB, Leary DR, Isbel NM. Kidney transplant outcomes are related to tacrolimus, mycophenolic acid and prednisolone exposure in the first week. Transpl Int 2012; 25:1182-93. [DOI: 10.1111/j.1432-2277.2012.01553.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
38
|
Udy AA, Varghese JM, Altukroni M, Briscoe S, McWhinney BC, Ungerer JP, Lipman J, Roberts JA. Subtherapeutic Initial β-Lactam Concentrations in Select Critically Ill Patients. Chest 2012; 142:30-39. [DOI: 10.1378/chest.11-1671] [Citation(s) in RCA: 295] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
|
39
|
Joffe M, Necula AS, Chand R, McWhinney BC, Krishnamurthy B, Loudovaris T, Goodman D, Thomas HE, Kay TWH, Mannering SI. Residual methylprednisolone suppresses human T-cell responses to spleen, but not islet, extracts from deceased organ donors. Int Immunol 2012; 24:447-53. [PMID: 22378502 DOI: 10.1093/intimm/dxs042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pancreatic islets, transplanted into recipients with type 1 diabetes, are exposed to allogenic and auto-immune T-cell responses. We set out to develop an assay to measure these responses using PBMC. Our approach was to prepare spleen extract from the islet donors (allo-antigen) and islet extracts (auto-antigen). To our surprise, we found that spleen extracts potently inhibited the proliferation of human T cells driven by antigen (tetanus toxoid) and mitogen (anti-CD3 mAb, OKT3), whereas extracts prepared from pancreatic islets from the same donor did not suppress T-cell proliferation. Suppression mediated by spleen extracts was unaffected by blocking mAbs against the IL-10R, transforming growth factor-β or CD152 (CTLA-4). It was also unaffected by denaturing the spleen extracts by heating, exposing to reducing agents or protease digestion. Because deceased organ donors are commonly given the immunosuppressive glucocorticoid methylprednisolone prior to death, we hypothesized that suppression was due to residual methylprednisolone in the spleen extracts. Methylprednisolone could be detected by mass spectrometry in spleen extracts at concentrations that suppress T-cell proliferation. Finally, the glucocorticoid receptor antagonist mifepristone completely reversed the suppression caused by the spleen extracts. We conclude that extracts of human spleen, but not islets, from deceased organ donors contain sufficient residual methylprednisolone to suppress the proliferation of T-cells in vitro.
Collapse
Affiliation(s)
- Max Joffe
- Immunology and Diabetes Unit, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Pretorius CJ, Galligan JP, McWhinney BC, Briscoe SE, Ungerer JP. Free cortisol method comparison: Ultrafiltation, equilibrium dialysis, tracer dilution, tandem mass spectrometry and calculated free cortisol. Clin Chim Acta 2011; 412:1043-7. [DOI: 10.1016/j.cca.2011.02.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Revised: 02/11/2011] [Accepted: 02/11/2011] [Indexed: 11/28/2022]
|
41
|
McWhinney BC, Briscoe SE, Ungerer JP, Pretorius CJ. Measurement of cortisol, cortisone, prednisolone, dexamethasone and 11-deoxycortisol with ultra high performance liquid chromatography–tandem mass spectrometry: Application for plasma, plasma ultrafiltrate, urine and saliva in a routine laboratory. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:2863-9. [DOI: 10.1016/j.jchromb.2010.08.044] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 08/20/2010] [Accepted: 08/30/2010] [Indexed: 10/19/2022]
|
42
|
McWhinney BC, Wallis SC, Hillister T, Roberts JA, Lipman J, Ungerer JP. Analysis of 12 beta-lactam antibiotics in human plasma by HPLC with ultraviolet detection. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:2039-43. [DOI: 10.1016/j.jchromb.2010.05.027] [Citation(s) in RCA: 143] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2009] [Revised: 05/03/2010] [Accepted: 05/18/2010] [Indexed: 10/19/2022]
|
43
|
Freshwater-Turner D, Udy A, Lipman J, Deans R, Stuart J, Boots R, Hegde R, McWhinney BC. Autonomic dysfunction in tetanus - what lessons can be learnt with specific reference to alpha-2 agonists? Anaesthesia 2007; 62:1066-70. [PMID: 17845661 DOI: 10.1111/j.1365-2044.2007.05217.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Severe tetanus is seen infrequently in the developed world, but often requires intensive care support. Mechanical ventilation with neuromuscular blockade and heavy sedation, good wound care and prompt administration of antitoxin are important. The management of autonomic dysfunction remains challenging. We measured serum catecholamine levels in a patient with severe tetanus in whom autonomic crises were a major and persistent feature, and investigated the impact of sedatives plus alpha(2)-agonists on these levels. Serum adrenaline levels were elevated up to 100-fold with clinically observed crises, although noradrenaline levels were much more difficult to interpret. There was no appreciable difference in catecholamine levels following administration of alpha(2)-agonists in the doses we used, although clonidine did allow easier control of crises with other agents. This case highlights some important lessons in the management of severe tetanus.
Collapse
Affiliation(s)
- D Freshwater-Turner
- Department of Anaesthesiology and Critical Care, University of Queensland, Level 3 Ned Hanlon Building, RBWH, Butterfield Street, Herston, Qld 4029, Australia
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Morton JM, Williamson S, Kear LM, McWhinney BC, Potter J, Glanville AR. Therapeutic Drug Monitoring of Prednisolone After Lung Transplantation. J Heart Lung Transplant 2006; 25:557-63. [PMID: 16678035 DOI: 10.1016/j.healun.2005.11.460] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 11/17/2005] [Accepted: 11/27/2005] [Indexed: 10/24/2022] Open
Abstract
BACKGROUND Despite well-known and serious potential side-effects of corticosteroid therapy, therapeutic drug monitoring (TDM) of prednisolone is rarely performed after lung transplantation (LTx). METHODS We measured prednisolone exposure using a 6-hour area-under-the-curve (AUC) analysis in 52 LTx recipients (41 bilateral, 9 single and 2 heart-lung), who were 99 +/- 13 (mean +/- SEM) weeks (range 4 to 380) post-LTx. Fourteen of 52 had cystic fibrosis (CF), and 36 of 52 were on cyclosporine and 16 of 52 on tacrolimus. Prednisolone dose was 9.8 +/- 0.7 mg/day (range 1 to 20). RESULTS Only 9 of 52 LTx patients had a prednisolone AUC within the previously reported reference range for healthy adult control subjects (170 to 260 nmol x hr/liter/milligram prednisolone). Six patients had values below and 37 above this range. Prednisolone AUC was higher in patients with CF compared with non-CF patients (511 +/- 82 vs 349 +/- 27 nmol x hr/liter/milligram, p < 0.02) and 70% of LTx recipients had measurable prednisolone levels at baseline (26.5 +/- 4.5 nmol/liter), unlike normal controls. CONCLUSIONS LTx recipients show a wide inter-individual variation in prednisolone pharmacokinetics; therefore, many are overdosed on conventional protocols. Side-effects of corticosteroid therapy remain a major clinical problem after transplantation, justifying the use of prednisolone TDM to optimize dosing and minimize morbidity.
Collapse
Affiliation(s)
- Judith M Morton
- Lung Transplant Unit, St. Vincent's Hospital, Sydney, NSW, Australia.
| | | | | | | | | | | |
Collapse
|
45
|
Potter JM, McWhinney BC, Sampson L, Hickman PE. Area-Under-the-Curve Monitoring of Prednisolone for Dose Optimization in a Stable Renal Transplant Population. Ther Drug Monit 2004; 26:408-14. [PMID: 15257071 DOI: 10.1097/00007691-200408000-00011] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Renal transplant recipients were noted to appear cushingoid while on low doses of steroid as part of a triple therapy immunosuppression of cyclosporin A (CsA), prednisolone, and azathioprine. METHODS The study group comprised adult renal transplant recipients with stable graft function who had received their renal allograft a minimum of 1 year previously (43 studies undertaken in 22 men and 20 women) with median daily prednisone dose of 7 mg (range 3-10). The control group was healthy nontransplant subjects [median dose 10 mg (10-30)]. Prednisolone bioavailability was measured using a limited 6-hour area under the curve (AUC), with prednisolone measured using specific HPLC assay. RESULTS The median prednisolone AUC/mg dose for all transplant recipients was significantly greater than the control group by approximately 50% (316 nmol x h/L/mg prednisolone versus 218). AUC was significantly higher in female recipients (median 415 versus 297 for men) and in recipients receiving cyclosporin (348 versus 285). The highest AUC was in women on estrogen supplements who were receiving cyclosporin (median 595). A significantly higher proportion of patients on triple therapy had steroid side effects compared with those on steroid and azathioprine (17/27 versus 4/15), more women than men had side effects (14/16 versus 7/22), and the AUC/mg prednisone was greater in those with side effects than without (median 377 versus 288 nmol x h/L/mg). DISCUSSION The results are consistent with the hypothesis that CsA increases the bioavailability of prednisolone, most likely through inhibition of P-glycoprotein. The increased exposure to steroid increased the side-effect profile of steroids in the majority of patients. Because the major contributor to AUC is the maximum postdose concentration, it may be possible to use single-point monitoring (2 hours postdose) for routine clinical studies.
Collapse
Affiliation(s)
- Julia M Potter
- Queensland Health Pathology Service, Prince Charles Hospital, Brisbane, Queensland, Australia.
| | | | | | | |
Collapse
|
46
|
McWhinney BC, Ward G, Hickman PE. Improved HPLC method for simultaneous analysis of cortisol, 11-deoxycortisol, prednisolone, methylprednisolone, and dexamethasone in serum and urine. Clin Chem 1996; 42:979-81. [PMID: 8665696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- B C McWhinney
- Dept. of Chem. Pathol., Princess Alexandra Hosp., Woolloongabba, QLD, Australia
| | | | | |
Collapse
|
47
|
McWhinney BC, Ward G, Hickman PE. Improved HPLC method for simultaneous analysis of cortisol, 11-deoxycortisol, prednisolone, methylprednisolone, and dexamethasone in serum and urine. Clin Chem 1996. [DOI: 10.1093/clinchem/42.6.979] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- B C McWhinney
- Dept. of Chem. Pathol., Princess Alexandra Hosp., Woolloongabba, QLD, Australia
| | - G Ward
- Dept. of Chem. Pathol., Princess Alexandra Hosp., Woolloongabba, QLD, Australia
| | - P E Hickman
- Dept. of Chem. Pathol., Princess Alexandra Hosp., Woolloongabba, QLD, Australia
| |
Collapse
|
48
|
de Leacy EA, Cowley DM, Brown JM, McWhinney BC, Chalmers AH. Effect of oral citrate on calcium absorption after an oral load of calcium phosphate. Clin Chem 1989. [DOI: 10.1093/clinchem/35.7.1541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- E A de Leacy
- Dept. of Pathol., Misericordiae Public Hospital, South Brisbane, Queensland, Australia
| | - D M Cowley
- Dept. of Pathol., Misericordiae Public Hospital, South Brisbane, Queensland, Australia
| | - J M Brown
- Dept. of Pathol., Misericordiae Public Hospital, South Brisbane, Queensland, Australia
| | - B C McWhinney
- Dept. of Pathol., Misericordiae Public Hospital, South Brisbane, Queensland, Australia
| | - A H Chalmers
- Dept. of Pathol., Misericordiae Public Hospital, South Brisbane, Queensland, Australia
| |
Collapse
|
49
|
de Leacy EA, Cowley DM, Brown JM, McWhinney BC, Chalmers AH. Effect of oral citrate on calcium absorption after an oral load of calcium phosphate. Clin Chem 1989; 35:1541. [PMID: 2758607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- E A de Leacy
- Dept. of Pathol., Misericordiae Public Hospital, South Brisbane, Queensland, Australia
| | | | | | | | | |
Collapse
|
50
|
Cowley DM, McWhinney BC, Brown JM, Chalmers AH. Effect of citrate on the urinary excretion of calcium and oxalate: relevance to calcium oxalate nephrolithiasis. Clin Chem 1989; 35:23-8. [PMID: 2910576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Studies in 24 recurrent oxalate stone-formers have shown that values for urinary calcium excretion for this group on at-home diets vary significantly (P less than 0.001) more than values for creatinine excretions. By placing stone-formers on controlled in-hospital diets and measuring their calcium excretions, we were able to predict probable outpatient hypercalciuria (greater than 7.5 mmol/day) with a sensitivity of 95% and a specificity of 95%. In this study, the renal loss of calcium during low-calcium diets was proportional to the absorptive hypercalciuria during high-calcium diets. Calcium loading experiments in fasted stone-formers and normal subjects indicated that citrate, at citrate:calcium molar ratios ranging from 0.12 to 1, stimulated urinary calcium excretion more than did calcium carbonate loading alone. In addition, citrate also significantly (P less than 0.05) increased the excretion of urinary oxalate by two normal subjects for a given load of calcium oxalate. Malabsorption of citrate and possibly other hydroxycarboxylic acids may thus predispose to oxalate nephrolithiasis by promoting calcium and oxalate absorption.
Collapse
Affiliation(s)
- D M Cowley
- Department of Pathology, Mater Misericordiae Public Hospitals, South Brisbane, Queensland, Australia
| | | | | | | |
Collapse
|