1
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Heidari S, Khalili H. Linezolid pharmacokinetics: a systematic review for the best clinical practice. Eur J Clin Pharmacol 2023; 79:195-206. [PMID: 36565357 DOI: 10.1007/s00228-022-03446-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 12/15/2022] [Indexed: 12/25/2022]
Abstract
OBJECTIVES To summarize the pharmacokinetics of linezolid to optimize the dosing regimen in special populations. METHODS A literature search was performed in three largest medical databases, including Embase, Scopus, and PubMed. The main applied keywords were linezolid and pharmacokinetics. Of 3663 retrieved publications in the English language, 35 original research articles, clinical studies, and case reports about linezolid pharmacokinetics in different populations such as pregnant women, pediatrics, elderly subjects, obese people, individuals with organ dysfunction, and critically ill patients were included. RESULTS AND CONCLUSION: Dose adjustment is not currently recommended for linezolid in patients with mild to moderate renal or hepatic impairment, older adults, and pregnant women. Although dose adjustment is not recommended in patients with severe renal or hepatic impairment, it should be considered that these patients are more vulnerable to linezolid adverse effects and drug interactions. In pediatrics, reducing the linezolid dosing interval to 8 h is suggested. Despite the lack of sufficient information in obese individuals, dosing based on body weight or use of higher dose seems to be justifiable to prevent sub-therapeutic concentrations. Although dose adjustment of linezolid is not recommended in critically ill patients, administration of linezolid as continuous intravenous infusion is suggested in this population. Blood level monitoring should be considered in populations that are vulnerable to linezolid underexposure (such as critically ill patients with augmented renal clearance, pediatrics, overweight, and obese patients) or overexposure (such as elderly, patients with hepatic and renal impairment). To assess the efficacy and safety of linezolid, the area under the concentration-time curve over 24 h to minimum inhibitory concentration (AUC0-24 h/MIC) equal to 80-120, percentage of time above the MIC ≥ 85%, and serum trough concentration between 2 and 7 mg/L are suggested.
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Affiliation(s)
- Shima Heidari
- Department of Clinical Pharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Khalili
- Department of Clinical Pharmacy, Faculty of Pharmacy, Research Center for Antibiotic Stewardship and Antimicrobial Resistance, Tehran University of Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran.
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2
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Lloyd EC, Cogen JD, Maples H, Bell SC, Saiman L. Antimicrobial Stewardship in Cystic Fibrosis. J Pediatric Infect Dis Soc 2022; 11:S53-S61. [PMID: 36069899 DOI: 10.1093/jpids/piac071] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 07/06/2022] [Indexed: 12/14/2022]
Abstract
The chronic airway infection and inflammation characteristic of cystic fibrosis (CF) ultimately leads to progressive lung disease, the primary cause of death in persons with CF (pwCF). Despite many recent advances in CF clinical care, efforts to preserve lung function in many pwCF still necessitate frequent antimicrobial use. Incorporating antimicrobial stewardship (AMS) principles into management of pulmonary exacerbations (PEx) would facilitate development of best practices for antimicrobial utilization at CF care centers. However, AMS can be challenging in CF given the unique aspects of chronic, polymicrobial infection in the CF airways, lack of evidence-based guidelines for managing PEx, limited utility for antimicrobial susceptibility testing, and increased frequency of adverse drug events in pwCF. This article describes current evidence-based antimicrobial treatment strategies for pwCF, highlights the potential for AMS to beneficially impact CF care, and provides practical strategies for integrating AMS programs into the management of PEx in pwCF.
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Affiliation(s)
- Elizabeth C Lloyd
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jonathan D Cogen
- Department of Pediatrics, Division of Pulmonary and Sleep Medicine, Seattle Children's Hospital, Seattle, Washington, USA
| | - Holly Maples
- Department of Pharmacy Practice, University of Arkansas for Medical Sciences College of Pharmacy, Little Rock, Arkansas, USA.,Quality and Safety Division, Arkansas Children's, Little Rock, Arkansas, USA
| | - Scott C Bell
- Department of Thoracic Medicine, The Prince Charles Hospital, Brisbane, Queensland, Australia.,Children's Health Research Centre, The University of Queensland, Brisbane, Queensland, Australia.,Translational Research Institute, Brisbane, Queensland, Australia
| | - Lisa Saiman
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA.,Department of Infection Prevention and Control, NewYork-Presbyterian Hospital, New York, New York, USA
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3
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Subtherapeutic Linezolid Concentration in a Patient With Bullous Pemphigoid Complicated by Methicillin-Resistant Staphylococcus aureus Infection: A Case Study. Ther Drug Monit 2021; 42:515-517. [PMID: 32217880 DOI: 10.1097/ftd.0000000000000758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We presented a case of subtherapeutic linezolid concentration in a patient with bullous pemphigoid characterized by large area skin anabrosis complicated by methicillin-resistant Staphylococcus aureus infections.
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4
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Epps QJ, Epps KL, Young DC, Zobell JT. State of the art in cystic fibrosis pharmacology optimization of antimicrobials in the treatment of cystic fibrosis pulmonary exacerbations: III. Executive summary. Pediatr Pulmonol 2021; 56:1825-1837. [PMID: 33656280 DOI: 10.1002/ppul.25353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/23/2021] [Accepted: 02/27/2021] [Indexed: 12/14/2022]
Abstract
Acute pulmonary exacerbations are complications of cystic fibrosis (CF) and are associated with increased morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA) and Aspergillus fumigatus are organisms that have been detected in the lungs of CF patients. The focus of this review is to provide an overview of the classes of antimicrobials used for MRSA and allergic bronchopulmonary aspergillosis (ABPA), a hypersensitivity reaction caused by A. fumigatus. The current anti-MRSA antibiotics and medications for ABPA dosing recommendations are discussed. This article also reviews the findings from the MRSA utilization surveys and the pharmacokinetic and pharmacodynamic differences between CF and non-CF patients. Antimethicillin S. aureus antibiotics include ceftaroline, clindamycin, fluoroquinolone derivatives (ciprofloxacin, levofloxacin), glycopeptide derivatives (telavancin, vancomycin), linezolid, rifampin, sulfamethoxazole/trimethoprim, and tetracycline derivatives (doxycycline, minocycline, tigecycline). Medications used for ABPA include corticosteroids, amphotericin B, azole antifungals (isavuconazole, itraconazole, posaconazole, voriconazole), and a monoclonal antibody, omalizumab.
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Affiliation(s)
- Quovadis J Epps
- Florida Agricultural and Mechanical University College of Pharmacy and Pharmaceutical Sciences, Jacksonville, Florida, USA
| | - Kevin L Epps
- Department of Pharmacy, The Mayo Clinic, Jacksonville, Florida, USA
| | - David C Young
- Department of Pharmacotherapy, L.S. Skaggs Pharmacy Institute, University of Utah College of Pharmacy, Salt Lake City, Utah, USA.,Department of Pharmacy, University of Utah Adult Cystic Fibrosis Center, Salt Lake City, Utah, USA
| | - Jeffery T Zobell
- Department of Pharmacy, Intermountain Primary Children's Hospital, Salt Lake City, Utah, USA.,Department of Pharmacy, Primary Children's Cystic Fibrosis Center, Salt Lake City, Utah, USA
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5
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Pharmacokinetics and pharmacodynamics of antibiotics in cystic fibrosis: a narrative review. Int J Antimicrob Agents 2021; 58:106381. [PMID: 34157401 DOI: 10.1016/j.ijantimicag.2021.106381] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 05/21/2021] [Accepted: 06/10/2021] [Indexed: 12/22/2022]
Abstract
Cystic fibrosis affects several organs, predisposing patients to severe bacterial respiratory infections, including those caused by methicillin-resistant Staphylococcus aureus. Cystic fibrosis is also associated with a wide spectrum of pathological changes that can significantly affect the absorption, distribution, metabolism, and/or elimination of several drugs, including antibacterial agents. Therefore, awareness of the pharmacokinetic derangements in patients with cystic fibrosis is mandatory for the optimisation of antibiotic therapy. This review discusses the basic principles of pharmacokinetics and the pathophysiology of the pharmacokinetics changes associated with cystic fibrosis; it also provides an update of available data for the most widely used antibiotics. Evidence accumulated in the last few years has clearly shown that a significant number of cystic fibrosis patients treated with conventional dosing schemes have sub-therapeutic antibiotic concentrations, increasing their risk of therapeutic failure and/or the emergence of resistant pathogens. Some proposals to optimise antibiotic therapies in this clinical setting based on therapeutic drug monitoring are also discussed.
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6
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Burke A, Smith D, Coulter C, Bell SC, Thomson R, Roberts JA. Clinical Pharmacokinetic and Pharmacodynamic Considerations in the Drug Treatment of Non-Tuberculous Mycobacteria in Cystic Fibrosis. Clin Pharmacokinet 2021; 60:1081-1102. [PMID: 33982266 DOI: 10.1007/s40262-021-01010-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2021] [Indexed: 10/21/2022]
Abstract
Non-tuberculous mycobacteria (NTM) are an emerging group of pulmonary infectious pathogens of increasing importance to the management of patients with cystic fibrosis (CF). NTM include slow-growing mycobacteria such as Mycobacterium avium complex (MAC) and rapidly growing mycobacteria such as Mycobacterium abscessus. The incidence of NTM in the CF population is increasing and infection contributes to significant morbidity to the patient and costs to the health system. Treating M. abscessus requires the combination of multiple costly antibiotics for months, with potentially significant toxicity associated with treatment. Although international guidelines for the treatment of NTM infection in CF are available, there are a lack of robust pharmacokinetic studies in CF patients to inform dosing and drug choice. This paper aims to outline the pharmacokinetic and pharmacodynamic factors informing the optimal treatment of NTM infections in CF.
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Affiliation(s)
- Andrew Burke
- Thoracic Medicine, The Prince Charles Hospital, Brisbane, QLD, Australia.,Faculty of Medicine, The University of Queensland School of Medicine, Brisbane, QLD, Australia
| | - Daniel Smith
- Thoracic Medicine, The Prince Charles Hospital, Brisbane, QLD, Australia.,Faculty of Medicine, The University of Queensland School of Medicine, Brisbane, QLD, Australia
| | - Chris Coulter
- Thoracic Medicine, The Prince Charles Hospital, Brisbane, QLD, Australia.,Faculty of Medicine, The University of Queensland School of Medicine, Brisbane, QLD, Australia
| | - Scott C Bell
- Thoracic Medicine, The Prince Charles Hospital, Brisbane, QLD, Australia.,Faculty of Medicine, The University of Queensland School of Medicine, Brisbane, QLD, Australia.,QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Rachel Thomson
- Thoracic Medicine, The Prince Charles Hospital, Brisbane, QLD, Australia.,Faculty of Medicine, The University of Queensland School of Medicine, Brisbane, QLD, Australia.,Immunology Department, Gallipoli Medical Research Institute, Brisbane, QLD, Australia
| | - Jason A Roberts
- Faculty of Medicine, University of Queensland Centre for Clinical Research, The University of Queensland, Brisbane, QLD, Australia. .,Department of Pharmacy, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia. .,Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia. .,Division of Anaesthesiology Critical Care Emergency and Pain Medicine, Nîmes University Hospital, University of Montpellier, Nîmes, France.
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7
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Pharmacokinetic and Pharmacodynamic Optimization of Antibiotic Therapy in Cystic Fibrosis Patients: Current Evidences, Gaps in Knowledge and Future Directions. Clin Pharmacokinet 2021; 60:409-445. [PMID: 33486720 DOI: 10.1007/s40262-020-00981-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2020] [Indexed: 10/22/2022]
Abstract
Antibiotic therapy is one of the main treatments for cystic fibrosis (CF). It aims to eradicate bacteria during early infection, calms down the inflammatory process, and leads to symptom resolution of pulmonary exacerbations. CF can modify both the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of antibiotics, therefore specific PK/PD endpoints should be determined in the context of CF. Currently available data suggest that optimal PK/PD targets cannot be attained in sputum with intravenous aminoglycosides. Continuous infusion appears preferable for β-lactam antibiotics, but optimal concentrations in sputum are unlikely to be reached, with some possible exceptions such as meropenem and ceftolozane. Usual doses are likely suboptimal for fluoroquinolones and linezolid, whereas daily doses of 45-60 mg/kg and 200 mg could be convenient for vancomycin and doxycycline, respectively. Weekly azithromycin doses of 22-30 mg/kg could also be appropriate for its anti-inflammatory effect. The difficulty with achieving optimal concentrations supports the use of combined treatments and the inhaled administration route, as very high local concentrations, concomitantly with low systemic exposure, can be obtained with the inhaled route for aminoglycosides, colistin, and fluoroquinolones, thus minimizing the risk of toxicity.
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8
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Epps QJ, Epps KL, Young DC, Zobell JT. State of the art in cystic fibrosis pharmacology-Optimization of antimicrobials in the treatment of cystic fibrosis pulmonary exacerbations: I. Anti-methicillin-resistant Staphylococcus aureus (MRSA) antibiotics. Pediatr Pulmonol 2020; 55:33-57. [PMID: 31609097 DOI: 10.1002/ppul.24537] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 09/19/2019] [Indexed: 12/22/2022]
Abstract
Acute pulmonary exacerbations (APE) are a complication of cystic fibrosis (CF) and are associated with morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA) is one of many organisms that has been detected in the airways of patients with CF. This review provides an evidence-based summary of pharmacokinetic/pharmacodynamic (PK/PD), tolerability, and efficacy studies utilizing anti-MRSA antibiotics (ie, ceftaroline, clindamycin, fluoroquinolone derivatives (ciprofloxacin, levofloxacin), glycopeptide derivatives (telavancin, vancomycin), linezolid, rifampin, sulfamethoxazole/trimethoprim (SMZ/TMP), and tetracycline derivatives (doxycycline, minocycline, tigecycline) in the treatment of APE and identifies areas where further study is warranted. A recent utilization study of antimicrobials for anti-MRSA has shown some CF Foundation accredited care centers and affiliate programs are using doses higher than the FDA-approved doses. Further studies are needed to determine the PK/PD properties in CF patients with clindamycin, minocycline, rifampin, SMZ/TMP, telavancin, and tigecycline; as well as, efficacy and tolerability studies with ciprofloxacin, clindamycin, doxycycline, levofloxacin, minocycline, rifampin, SMZ/TMP, in CF patients with MRSA.
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Affiliation(s)
- Quovadis J Epps
- Florida Agricultural and Mechanical University College of Pharmacy and Pharmaceutical Sciences, Jacksonville, Florida
| | - Kevin L Epps
- Department of Pharmacy, The Mayo Clinic, Jacksonville, Florida
| | - David C Young
- L.S. Skaggs Pharmacy Institute, University of Utah College of Pharmacy, Salt Lake City, Utah
- University of Utah Adult Cystic Fibrosis Center, Salt Lake City, Utah
| | - Jeffery T Zobell
- Department of Pharmacy, Intermountain Primary Children's Hospital, Salt Lake City, Utah
- Primary Children's Cystic Fibrosis Center, Salt Lake City, Utah
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9
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Fusco NM, Meaney CJ, Frederick CA, Prescott WA. Comparative Effectiveness of Vancomycin Versus Linezolid for the Treatment of Acute Pulmonary Exacerbations of Cystic Fibrosis. Ann Pharmacother 2019; 54:197-204. [DOI: 10.1177/1060028019885651] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: Data are limited regarding the preferred antibiotics for treatment of acute pulmonary exacerbations (APEs) of cystic fibrosis (CF), when methicillin-resistant Staphylococcus aureus (MRSA) is suspected. Objective: To compare the rate of return to baseline lung function among individuals with APEs of CF treated with either vancomycin or linezolid. Methods: This retrospective study included individuals hospitalized for APEs of CF from May 1, 2015, to April 30, 2017 who were infected with MRSA and treated with vancomycin or linezolid. The primary outcome was the return to baseline lung function, as measured by forced expiratory volume in 1 s (FEV1). Descriptive and inferential statistics were used. All tests were 2-tailed with α set at 0.05. Results: A total of 122 encounters were included (vancomycin: n = 66; linezolid: n = 66). No difference existed in return to baseline FEV1 between vancomycin (53 [80.3%]) and linezolid (50 [75.8%]; P = 0.53); nor was there a difference in median percentage change in FEV1 from admission to follow-up between vancomycin (24.7%) and linezolid (20.7%; P = 0.61). Adverse drug events occurred more frequently in patient encounters treated with vancomycin (10 [15.2%]) compared with linezolid (2 [3%]; P = 0.002). Conclusion and Relevance: Our study observed no difference in the effectiveness of vancomycin compared with linezolid in terms of change in lung function for APEs of CF. The rate of adverse drug events was low. In individuals with CF infected with MRSA who are experiencing an APE, either vancomycin or linezolid appear to be viable treatment options.
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Affiliation(s)
- Nicholas M. Fusco
- University at Buffalo School of Pharmacy and Pharmaceutical Sciences, Buffalo, NY, USA
| | - Calvin J. Meaney
- University at Buffalo School of Pharmacy and Pharmaceutical Sciences, Buffalo, NY, USA
| | | | - William A. Prescott
- University at Buffalo School of Pharmacy and Pharmaceutical Sciences, Buffalo, NY, USA
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10
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Esposito S, Pennoni G, Mencarini V, Palladino N, Peccini L, Principi N. Antimicrobial Treatment of Staphylococcus aureus in Patients With Cystic Fibrosis. Front Pharmacol 2019; 10:849. [PMID: 31447669 PMCID: PMC6692479 DOI: 10.3389/fphar.2019.00849] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/03/2019] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus aureus is a ubiquitous human commensal pathogen. It is commonly isolated in cystic fibrosis (CF) patients and is considered one of the main causes of the recurrent acute pulmonary infections and progressive decline in lung function that characterize this inherited life-threatening multisystem disorder. However, the true role of S. aureus in CF patients is not completely understood. The main aim of this narrative review is to discuss the present knowledge of the role of S. aureus in CF patients. Literature review showed that despite the fact that the availability and use of drugs effective against S. aureus have coincided with a significant improvement in the prognosis of lung disease in CF patients, clearly evidencing the importance of S. aureus therapy, how to use old and new drugs to obtain the maximal effectiveness has not been precisely defined. The most important problem remains that the high frequency with which S. aureus is carried in healthy subjects prevents the differentiation of simple colonization from infection. Moreover, although experts recommend antibiotic administration in CF patients with symptoms and in those with persistent detection of S. aureus, the best antibiotic approach has not been defined. All these problems are complicated by the evidence that the most effective antibiotic against methicillin-resistant S. aureus (MRSA) cannot be used in patients with CF with the same schedules used in patients without CF. Further studies are needed to solve these problems and to assure CF patients the highest level of care.
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Affiliation(s)
- Susanna Esposito
- Pediatric Clinic, Cystic Fibrosis Center of Umbria Region, Department of Surgical and Biomedical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Guido Pennoni
- Pediatric Unit, Cystic Fibrosis Center of Umbria Region, Branca Hospital, Branca, Italy
| | - Valeria Mencarini
- Pediatric Unit, Cystic Fibrosis Center of Umbria Region, Branca Hospital, Branca, Italy
| | - Nicola Palladino
- Pediatric Unit, Cystic Fibrosis Center of Umbria Region, Branca Hospital, Branca, Italy
| | - Laura Peccini
- Pediatric Clinic, Cystic Fibrosis Center of Umbria Region, Department of Surgical and Biomedical Sciences, Università degli Studi di Perugia, Perugia, Italy
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12
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Applicability of a Single Time Point Strategy for the Prediction of Area Under the Concentration Curve of Linezolid in Patients: Superiority of Ctrough- over Cmax-Derived Linear Regression Models. Drugs R D 2016; 16:69-79. [PMID: 26747454 PMCID: PMC4767722 DOI: 10.1007/s40268-015-0117-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Background and Objectives Linezolid, a oxazolidinone, was the first in class to be approved for the treatment of bacterial infections arising from both susceptible and resistant strains of Gram-positive bacteria. Since overt exposure of linezolid may precipitate serious toxicity issues, therapeutic drug monitoring (TDM) may be required in certain situations, especially in patients who are prescribed other co-medications. Methods Using appropriate oral pharmacokinetic data (single dose and steady state) for linezolid, both maximum plasma drug concentration (Cmax) versus area under the plasma concentration–time curve (AUC) and minimum plasma drug concentration (Cmin) versus AUC relationship was established by linear regression models. The predictions of the AUC values were performed using published mean/median Cmax or Cmin data and appropriate regression lines. The quotient of observed and predicted values rendered fold difference calculation. The mean absolute error (MAE), root mean square error (RMSE), correlation coefficient (r), and the goodness of the AUC fold prediction were used to evaluate the two models. Results The Cmax versus AUC and trough plasma concentration (Ctrough) versus AUC models displayed excellent correlation, with r values of >0.9760. However, linezolid AUC values were predicted to be within the narrower boundary of 0.76 to 1.5-fold by a higher percentage by the Ctrough (78.3 %) versus Cmax model (48.2 %). The Ctrough model showed superior correlation of predicted versus observed values and RMSE (r = 0.9031; 28.54 %, respectively) compared with the Cmax model (r = 0.5824; 61.34 %, respectively). Conclusions A single time point strategy of using Ctrough level is possible as a prospective tool to measure the AUC of linezolid in the patient population.
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13
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Muirhead CA, Sanford JN, McCullar BG, Nolt D, MacDonald KD. One Center's Guide to Outpatient Management of Pediatric Cystic Fibrosis Acute Pulmonary Exacerbation. Clin Med Insights Pediatr 2016; 10:57-65. [PMID: 27429564 PMCID: PMC4944828 DOI: 10.4137/cmped.s38336] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/06/2016] [Accepted: 06/13/2016] [Indexed: 01/20/2023] Open
Abstract
Cystic fibrosis (CF) is a chronic disorder characterized by acute pulmonary exacerbations that comprise increased cough, chest congestion, increased mucus production, shortness of breath, weight loss, and fatigue. Typically, severe episodes are treated in the inpatient setting and include intravenous antimicrobials, airway clearance therapy, and nutritional support. Children with less-severe findings can often be managed as outpatients with oral antimicrobials and increased airway clearance therapy at home without visiting the specialty CF center to begin treatment. Selection of specific antimicrobial agents is dependent on pathogens found in surveillance culture, activity of an agent in patients with CF, and the unique physiology of these patients. In this pediatric review, we present our practice for defining acute pulmonary exacerbation, deciding treatment location, initiating treatment either in-person or remotely, determining the frequency of airway clearance, selecting antimicrobial therapy, recommending timing for follow-up visit, and recognizing and managing treatment failures.
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Affiliation(s)
- Corinne A. Muirhead
- Department of Pharmacy, Oregon Health and Science University, Doernbecher Children’s Hospital, Portland, OR, USA
| | - Jillian N. Sanford
- Department of Pediatrics, Oregon Health and Science University, Doernbecher Children’s Hospital, Portland, OR, USA
| | - Benjamin G. McCullar
- Department of Nursing, Oregon Health and Science University, Doernbecher Children’s Hospital, Portland, OR, USA
| | - Dawn Nolt
- Department of Pediatrics, Oregon Health and Science University, Doernbecher Children’s Hospital, Portland, OR, USA
| | - Kelvin D. MacDonald
- Department of Pediatrics, Oregon Health and Science University, Doernbecher Children’s Hospital, Portland, OR, USA
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14
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Banniettis N, Sharma R, Hand I, Peloquin CA, Kohlhoff S, Hammerschlag MR. Steady-state pharmacokinetics of oral linezolid suspension in a premature infant with osteomyelitis. J Antimicrob Chemother 2016; 71:1738. [PMID: 26851607 DOI: 10.1093/jac/dkv507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Natalie Banniettis
- Department of Pediatrics, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY, USA
| | - Roopali Sharma
- Department of Pharmacy Practice, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY, USA
| | - Ivan Hand
- Department of Pediatrics, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY, USA
| | - Charles A Peloquin
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida, PO Box 100486, Gainesville, FL, USA
| | - Stephan Kohlhoff
- Department of Pediatrics, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY, USA
| | - Margaret R Hammerschlag
- Department of Pediatrics, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY, USA
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15
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Yu D, Stach LM, Newland JG. Linezolid-Resistant Staphylococcus aureus in Children With Cystic Fibrosis. J Pediatric Infect Dis Soc 2015; 4:e163-5. [PMID: 26501474 DOI: 10.1093/jpids/piv071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 09/18/2015] [Indexed: 02/04/2023]
Affiliation(s)
- Diana Yu
- Department of Pharmacy, Children's Mercy Hospital, Kansas City, Missouri
| | - Leslie M Stach
- Department of Pharmacy, Ann & Robert H. Lurie Children's Hospital of Chicago, Illinois
| | - Jason G Newland
- Department of Pediatrics, Children's Mercy Hospital, Kansas City, Missouri
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16
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Molloy L, Nichols K. Infectious Diseases Pharmacotherapy for Children With Cystic Fibrosis. J Pediatr Health Care 2015; 29:565-78; quiz 579-80. [PMID: 26498903 DOI: 10.1016/j.pedhc.2015.07.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 12/15/2022]
Abstract
Cystic fibrosis (CF) affects several organs, most notably the lungs, which become predisposed to infections with potentially severe consequences. Because of physiologic changes and infection characteristics, unique approaches to antimicrobial agent selection, dosing, and administration are needed. To provide optimal acute and long-term care, pediatric health care providers must be aware of these patient features and common approaches to antimicrobial therapy in CF, which can differ significantly from those of other infectious diseases. The purpose of this article is to review common respiratory pathogens, pharmacology of commonly used antimicrobial agents, and unique pharmacokinetics and dosing strategies often used when treating children with CF.
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17
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Antibiotic management of lung infections in cystic fibrosis. I. The microbiome, methicillin-resistant Staphylococcus aureus, gram-negative bacteria, and multiple infections. Ann Am Thorac Soc 2015; 11:1120-9. [PMID: 25102221 DOI: 10.1513/annalsats.201402-050as] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite significant advances in treatment strategies targeting the underlying defect in cystic fibrosis (CF), airway infection remains an important cause of lung disease. In this two-part series, we review recent evidence related to the complexity of CF airway infection, explore data suggesting the relevance of individual microbial species, and discuss current and future treatment options. In Part I, the evidence with respect to the spectrum of bacteria present in the CF airway, known as the lung microbiome is discussed. Subsequently, the current approach to treat methicillin-resistant Staphylococcus aureus, gram-negative bacteria, as well as multiple coinfections is reviewed. Newer molecular techniques have demonstrated that the airway microbiome consists of a large number of microbes, and the balance between microbes, rather than the mere presence of a single species, may be relevant for disease pathophysiology. A better understanding of this complex environment could help define optimal treatment regimens that target pathogens without affecting others. Although relevance of these organisms is unclear, the pathologic consequences of methicillin-resistant S. aureus infection in patients with CF have been recently determined. New strategies for eradication and treatment of both acute and chronic infections are discussed. Pseudomonas aeruginosa plays a prominent role in CF lung disease, but many other nonfermenting gram-negative bacteria are also found in the CF airway. Many new inhaled antibiotics specifically targeting P. aeruginosa have become available with the hope that they will improve the quality of life for patients. Part I concludes with a discussion of how best to treat patients with multiple coinfections.
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Zobell JT, Epps KL, Young DC, Montague M, Olson J, Ampofo K, Chin MJ, Marshall BC, Dasenbrook E. Utilization of antibiotics for methicillin-resistant Staphylococcus aureus infection in cystic fibrosis. Pediatr Pulmonol 2015; 50:552-9. [PMID: 25559432 DOI: 10.1002/ppul.23132] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Revised: 09/21/2014] [Accepted: 09/24/2014] [Indexed: 11/09/2022]
Abstract
OBJECTIVES The purpose of this study was to characterize the utilization of antibiotics for chronic methicillin-resistant Staphylococcus aureus (MRSA) infection in cystic fibrosis (CF) patients with acute pulmonary exacerbations (PEx). METHODS An anonymous national cross-sectional survey of CF Foundation accredited care programs was performed using an electronic survey tool. RESULTS Fifty-eight percent (152/261) CF Foundation accredited programs completed the survey. Ninety-eight percent (149/152) of respondents reported using antibiotics (oral or intravenous) against MRSA. Variability exists in the use of antibiotics amongst the programs and in the dosages utilized. For oral outpatient treatment, sulfamethoxazole/trimethoprim was the most commonly utilized antibiotic by both pediatric (109/287, 38%) and adult (99/295, 34%) respondents, of which, ten percent of reported to use it in combination with rifampin. For inpatient treatment, linezolid (both intravenous (IV) and oral) was most commonly utilized in both pediatric (IV 35/224, 16%; oral 41/224, 18%), and adult (IV 44/235, 19%; oral 38/235, 16%) respondents for inpatient treatment. IV vancomycin was the second most commonly utilized antibiotic by pediatric (70/224, 31%) and adult (71/235, 30%) respondents. Most respondents reported dose titration to achieve a vancomycin trough level of 15-20 mg/L (150/179, 84%). Topical or inhaled antibiotic utilization was reported to be an uncommon practice with approximately 70% of pediatric and adult respondents reporting to use them either rarely or never. The concomitant use of anti-MRSA and anti-pseudomonal antibiotics was common with 96% of pediatric and 99% of adult respondents answering in the affirmative. CONCLUSION We conclude that anti-MRSA antibiotics are utilized via various dosage regimens by a majority of CF Foundation accredited care programs for the treatment of chronic MRSA in PEx, and there is no consensus on the best treatment approach.
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Affiliation(s)
- Jeffery T Zobell
- Department of Pharmacy, Intermountain Primary Children's Hospital, Salt Lake City, Utah.,Intermountain Cystic Fibrosis Pediatric Center, Salt Lake City, Utah
| | - Kevin L Epps
- Department of Pharmacy, St. Vincent's Medical Center Riverside, Jacksonville, Florida
| | - David C Young
- L.S. Skaggs Pharmacy Institute Rm 4916, University of Utah College of Pharmacy, Salt Lake City, Utah.,Intermountain Cystic Fibrosis Adult Center, Salt Lake City, Utah
| | - Madison Montague
- Department of Pharmacy, Intermountain McKay-Dee Hospital Center, Ogden, Utah
| | - Jared Olson
- Department of Pharmacy, Intermountain Primary Children's Hospital, Salt Lake City, Utah
| | - Krow Ampofo
- Division of Pediatric Infectious Disease, University of Utah, Salt Lake City, Utah
| | | | | | - Elliott Dasenbrook
- Departments of Medicine and Pediatrics, Case Western Reserve University School of Medicine, University Hospitals Case Medical Center and Rainbow Babies and Children's Hospital, Cleveland, Ohio
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Roberts JK, Stockmann C, Balch A, Yu T, Ward RM, Spigarelli MG, Sherwin CMT. Optimal design in pediatric pharmacokinetic and pharmacodynamic clinical studies. Paediatr Anaesth 2015; 25:222-30. [PMID: 25580772 DOI: 10.1111/pan.12575] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/23/2014] [Indexed: 11/30/2022]
Abstract
It is not trivial to conduct clinical trials with pediatric participants. Ethical, logistical, and financial considerations add to the complexity of pediatric studies. Optimal design theory allows investigators the opportunity to apply mathematical optimization algorithms to define how to structure their data collection to answer focused research questions. These techniques can be used to determine an optimal sample size, optimal sample times, and the number of samples required for pharmacokinetic and pharmacodynamic studies. The aim of this review is to demonstrate how to determine optimal sample size, optimal sample times, and the number of samples required from each patient by presenting specific examples using optimal design tools. Additionally, this review aims to discuss the relative usefulness of sparse vs rich data. This review is intended to educate the clinician, as well as the basic research scientist, whom plan on conducting a pharmacokinetic/pharmacodynamic clinical trial in pediatric patients.
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Affiliation(s)
- Jessica K Roberts
- Division of Clinical Pharmacology, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, UT, USA
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20
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Fusco NM, Toussaint KA, Prescott WA. Antibiotic Management of Methicillin-Resistant Staphylococcus aureus–Associated Acute Pulmonary Exacerbations in Cystic Fibrosis. Ann Pharmacother 2015; 49:458-68. [DOI: 10.1177/1060028014567526] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Objective: To review the treatment of methicillin-resistant Staphylococcus aureus (MRSA)–associated acute pulmonary exacerbations (APEs) in cystic fibrosis (CF). Data Sources: A search of PubMed, MEDLINE, Cochrane Library and Clinicaltrials.gov databases through November 2014 was conducted using the search terms Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, pulmonary exacerbations, and cystic fibrosis. Study Selection and Data Extraction: All English-language research articles, case reports, and case series were evaluated. A total of 185 articles were identified related to MRSA and CF; 30 articles that studied treatments of MRSA APE in CF were included. Data Synthesis: The persistent presence of MRSA in the respiratory tract of patients with CF has been associated with higher morbidity and an increased risk of death. Limited clinical data exist supporting the efficacy of any specific antimicrobial currently available for the treatment of APE secondary to MRSA. Conclusions: Data extrapolated from other populations suggest that vancomycin and linezolid are appropriate first-line treatment options for the treatment of APE secondary to MRSA. Second-line options include doxycycline or minocycline and trimethoprim/sulfamethoxazole, each of which may be useful in patients coinfected with other respiratory pathogens, for which they may provide overlapping coverage. Ceftaroline and ceftobiprole are newer antibiotics that appear to have a potential role in the treatment of APE in CF, but the latter is not currently available to the US market. Although potentially useful, clindamycin is limited by high rates of resistance, telavancin is limited by its toxicity profile, and tigecycline is limited by a lack of demonstrated efficacy for infections that are similar to that seen in the CF population. Studies investigating the clinical utility of the above-cited antibiotics for APE in CF secondary to MRSA are desperately needed to broaden the treatment armamentarium for this medical condition.
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Affiliation(s)
- Nicholas M. Fusco
- University at Buffalo School of Pharmacy and Pharmaceutical Sciences, Buffalo, NY, USA
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21
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Matsumoto K, Shigemi A, Takeshita A, Watanabe E, Yokoyama Y, Ikawa K, Morikawa N, Takeda Y. Linezolid dosage in pediatric patients based on pharmacokinetics and pharmacodynamics. J Infect Chemother 2014; 21:70-3. [PMID: 25305808 DOI: 10.1016/j.jiac.2014.08.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/14/2014] [Accepted: 08/15/2014] [Indexed: 11/17/2022]
Abstract
Linezolid pharmacokinetic profile in pediatric patients has not been fully characterized, and the dose needed to achieve a pharmacokinetic-pharmacodynamic (PK-PD) target has yet to be established because its efficacy is associated with the area under the plasma drug concentration-time curve (AUC24)/minimum inhibitory concentration (MIC) ratio. The present study aimed to define the pharmacokinetic parameters of intravenous linezolid in pediatric patients and assess the rationale for the approved dosage recommendations. Linezolid was safe, tolerated well, and clinically effective for treating Gram-positive bacteria in five pediatric patients (3-11 years). The mean values for the volume of distribution and total clearance (CL) in a one-compartment model were estimated to be 0.646 ± 0.239 l/kg and 0.171 ± 0.068 l/h/kg, respectively (mean ± S.D.). Based on this analysis, the AUC24 and trough drug concentration in plasma (C(min)) for linezolid doses were predicted to be 175.4 μg h/ml and 3.4 μg/ml for 30 mg/kg/day, 204.7 μg h/ml and 4.3 μg/ml for 35 mg/kg/day, and 263.2 μg h/ml and 6.2 μg/ml for 45 mg/kg/day, respectively. Taking into account that AUC24 should be ≥ 200 μg h/ml for MIC of 2.0 μg/ml (to achieve an AUC24/MIC ratio of ≥ 100) and C(min) should be approximately 7 μg/ml (to avoid thrombocytopenia), we consider the approved dosage of 30 mg/kg/day to be fundamentally rational, but can be underdosed against bacteria with MIC of 2.0 μg/ml; therefore, a dose of 35-45 mg/kg/day is more appropriate to ensure the efficacy and safety of linezolid in pediatric patients.
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Affiliation(s)
- Kazuaki Matsumoto
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan
| | - Akari Shigemi
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan
| | - Ayumi Takeshita
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan
| | - Erika Watanabe
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan
| | - Yuta Yokoyama
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan; Department of Clinical Pharmacotherapy, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kazuro Ikawa
- Department of Clinical Pharmacotherapy, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Norifumi Morikawa
- Department of Clinical Pharmacotherapy, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Yasuo Takeda
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan.
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Cojutti P, Maximova N, Crichiutti G, Isola M, Pea F. Pharmacokinetic/pharmacodynamic evaluation of linezolid in hospitalized paediatric patients: a step toward dose optimization by means of therapeutic drug monitoring and Monte Carlo simulation. J Antimicrob Chemother 2014; 70:198-206. [DOI: 10.1093/jac/dku337] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Thigpen J, Odle B. Intravenous and Inhaled Antimicrobials at Home in Cystic Fibrosis Patients. HOME HEALTH CARE MANAGEMENT AND PRACTICE 2014. [DOI: 10.1177/1084822313501322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The primary clinical characteristics of cystic fibrosis (CF) are malnutrition caused by malabsorption secondary to pancreatic insufficiency, chronic pulmonary infections, and male infertility. The major cause of morbidity and mortality are bronchiectasis and obstructive pulmonary disease. Lung disease in CF is manifested by this chronic lung disease progression, with intermittent episodes of acute worsening of symptoms called pulmonary exacerbations. Once the patient has stabilized, and if suitable care can be arranged, these interventions are often transitioned to the home. This review summarizes important points pertinent to the use of intravenous and inhaled antimicrobials that may be encountered by prescribers, nurses, technicians, and case managers in the home health setting. Appropriate dosing, indications, adverse drug reactions, monitoring parameters, and practicality of both intravenous and inhaled antimicrobials are discussed.
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Affiliation(s)
- Jim Thigpen
- East Tennessee State University, Johnson City, USA
| | - Brian Odle
- East Tennessee State University, Johnson City, USA
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24
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Kirkby S, Novak K, McCoy K. Update on antibiotics for infection control in cystic fibrosis. Expert Rev Anti Infect Ther 2014; 7:967-80. [DOI: 10.1586/eri.09.82] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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25
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Lima DF, Brazão NBV, Folescu TW, Neves FP, Ferreira AG, Santos EA, Marques EA, Leão RS. Panton-Valentine leukocidin (PVL) gene carriage among Staphylococcus aureus strains with SCCmec types I, III, IV, and V recovered from cystic fibrosis pediatric patients in Brazil. Diagn Microbiol Infect Dis 2014; 78:59-62. [DOI: 10.1016/j.diagmicrobio.2013.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 09/05/2013] [Accepted: 10/02/2013] [Indexed: 12/19/2022]
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Abstract
We used the Pediatric Health Information System to evaluate linezolid use among hospitalized children. From 2003 to 2007, use increased 5-fold, including wide interhospital variation, then stabilized through 2011. Linezolid was responsible for 3% of total antibiotic expenditures. Children with respiratory, oncologic or transplant conditions were the most frequently treated with linezolid.
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Dose optimisation of antibiotics in children: application of pharmacokinetics/pharmacodynamics in paediatrics. Int J Antimicrob Agents 2013; 43:223-30. [PMID: 24389079 DOI: 10.1016/j.ijantimicag.2013.11.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 11/11/2013] [Indexed: 11/24/2022]
Abstract
The judicious use of antibiotics to combat infections in children relies upon appropriate selection of an agent, dose and duration to maximise efficacy and to minimise toxicity. Critical to dose optimisation is an understanding of the pharmacokinetics and pharmacodynamics of available drugs. Optimal dosing strategies may take advantage of pharmacokinetic/pharmacodynamic (PK/PD) principles so that antibiotic dosing can be individualised to assure effective bacterial killing in patients who have altered pharmacokinetics or who have infections with less susceptible or resistant organisms. This review will outline the fundamentals of antimicrobial pharmacokinetics/pharmacodynamics through discussion of antibacterial agents most often used in children. We aim to highlight the importance of dose optimisation in paediatrics and describe non-conventional dosing strategies that can take advantage of PK/PD principles at the bedside.
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Abstract
PURPOSE OF REVIEW Respiratory infection is a major contributor to morbidity and mortality in cystic fibrosis (CF). One infection the CF community is particularly concerned about is methicillin-resistant Staphylococcus aureus (MRSA). Worldwide, the prevalence of MRSA has been rising and the impact on clinical outcomes and optimal prevention and treatment strategies are unclear. RECENT FINDINGS Studies have demonstrated MRSA is independently associated with poor clinical outcomes, even after taking into account severity of illness. Additionally, characteristics of MRSA strains, such as small colony variants and borderline oxacillin-resistant S. aureus, may be important in predicting the subsequent clinical course. The treatment of MRSA has had variable results and emergence of resistance to commonly prescribed antibiotics is a concern. SUMMARY The evidence to date supports MRSA infection is independently associated with worse outcomes. The next step is to build upon the current research to expand the knowledge about the impact different strains of MRSA have on infection control strategies and MRSA treatment protocols. Interventions should balance patient safety, efficacy, and treatment burden to improve the quality and length of life in patients with CF.
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Goss CH, Muhlebach MS. Review: Staphylococcus aureus and MRSA in cystic fibrosis. J Cyst Fibros 2011; 10:298-306. [PMID: 21719362 DOI: 10.1016/j.jcf.2011.06.002] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 05/27/2011] [Accepted: 06/03/2011] [Indexed: 01/31/2023]
Abstract
BACKGROUND Staphylococcus aureus (S. aureus) is one of the earliest bacteria detected in infants and children with cystic fibrosis (CF). The rise of methicillin resistant S. aureus (MRSA) in the last 10 years has caused a lot of attention to this organism. RESULTS The aim of this review is to provide a general overview of methicillin sensitive S. aureus (MSSA) and MRSA, discuss special aspects of S. aureus in cystic fibrosis, and to review treatment concepts. Microbiology of the organism will be reviewed along with data regarding the epidemiology of both MSSA and MRSA. Antibiotic treatments both in regards to acute management and eradication of MSSA and MRSA will be reviewed. Prophylaxis of MSSA in CF remains controversial. Treatment with anti-staphylococcal agents reduces the infection rate with MSSA but may lead to a higher rate of infection with P. aeruginosa. In regards to MRSA, there is a paucity of clinical data regarding approaches to eradication. CONCLUSIONS To advance the care of CF patients, controlled clinical trials are urgently needed to find the optimal approach to treating CF patients who are infected with either MSSA or MRSA.
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Pharmacokinetics of intravenous and oral linezolid in adults with cystic fibrosis. Antimicrob Agents Chemother 2011; 55:3393-8. [PMID: 21518837 DOI: 10.1128/aac.01797-10] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Linezolid is a treatment option for methicillin-resistant Staphylococcus aureus (MRSA) infections in cystic fibrosis (CF) patients. Little is known, however, about its pharmacokinetics in this population. Eight adults with CF were randomized to receive intravenous (i.v.) and oral linezolid at 600 mg twice daily for 9 doses in a crossover design with a 9-day washout. Plasma samples were collected after the first and ninth doses of each phase. Population pharmacokinetic analyses were performed by nonlinear mixed-effects modeling using a previously described 2-compartment model with time-dependent clearance inhibition. Monte Carlo simulation was performed to assess the activities of the linezolid dosing regimens against 42 contemporary MRSA isolates recovered from CF patients. The following pharmacokinetic parameter estimates were observed for the population: absorption rate constant, 1.91 h(-1); clearance, 9.54 liters/h; volume of central compartment, 26.8 liters; volume of peripheral compartment, 17.3 liters; and intercompartmental clearance, 104 liters/h. Linezolid demonstrated nonlinear clearance after 9 doses, which was reduced by a mean of 38.9% (range, 28.8 to 59.9%). Mean bioavailability was 85% (range, 47 to 131%). At steady state, 600 mg given twice daily produced 93.0% and 87.2% probabilities of obtaining the target pharmacodynamic exposure against the MRSA isolates for the i.v. and oral formulations, respectively. Thrice-daily dosing increased the probabilities to 97.0% and 95.6%, respectively. Linezolid pharmacokinetics in these adults with CF were well described by a 2-compartment model with time-dependent clearance inhibition. Standard i.v. and oral dosing regimens should be sufficient to reliably attain pharmacodynamic targets against most MRSA isolates; however, more frequent dosing may be required for isolates with MICs of ≥ 2 μg/ml.
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Emergence of linezolid-resistant Staphylococcus aureus after prolonged treatment of cystic fibrosis patients in Cleveland, Ohio. Antimicrob Agents Chemother 2011; 55:1684-92. [PMID: 21263048 DOI: 10.1128/aac.01308-10] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Linezolid (LZD)-resistant Staphylococcus aureus (LRSA) isolates were monitored from 2000 to 2009 in Cleveland, OH. LRSA first emerged in 2004 only in cystic fibrosis (CF) patients, with 11 LRSA-infected CF patients being identified by 2009. LRSA was isolated from 8 of 77 CF patients with S. aureus respiratory tract infection treated with LZD from 2000 to 2006. Analysis of clinical data showed that the 8 CF patients with LRSA received more LZD courses (18.8 versus 5.9; P = 0.001) for a longer duration (546.5 versus 211.9 days; P < 0.001) and had extended periods of exposure to LZD (83.1 versus 30.1 days/year; P < 0.001) than the 69 with LZD-susceptible isolates. Five LRSA isolates included in the clinical analysis (2000 to 2006) and three collected in 2009 were available for molecular studies. Genotyping by repetitive extrapalindromic PCR and pulsed-field gel electrophoresis revealed that seven of these eight LRSA strains from unique patients were genetically similar. By multilocus sequence typing, all LRSA isolates were included in clonal complex 5 (seven of sequence type 5 [ST5] and one of ST1788, a new single-locus variant of ST5). However, seven different variants were identified by spa typing. According to the Escherichia coli numbering system, seven LRSA isolates contained a G2576T mutation (G2603T, S. aureus numbering) in one to four of the five copies of domain V of the 23S rRNA genes. One strain also contained a mutation (C2461T, E. coli numbering) not previously reported. Two strains, including one without domain V mutations, possessed single amino acid substitutions (Gly152Asp or Gly139Arg) in the ribosomal protein L3 of the peptidyltransferase center, substitutions not previously reported in clinical isolates. Emergence of LRSA is a serious concern for CF patients who undergo prolonged courses of LZD therapy.
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Di Paolo A, Malacarne P, Guidotti E, Danesi R, Del Tacca M. Pharmacological issues of linezolid: an updated critical review. Clin Pharmacokinet 2010; 49:439-47. [PMID: 20528004 DOI: 10.2165/11319960-000000000-00000] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Linezolid is the first oxazolidinone agent introduced into clinical practice for use against Gram-positive bacteria that are resistant to beta-lactams and glycopeptides, including methicillin (meticillin)-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). An optimal antibacterial effect is achieved when plasma drug concentrations are above the minimum inhibitory concentration (MIC) [T>MIC] for the entire length of treatment and the ratio between the area under the plasma concentration-time curve (AUC) and the MIC (AUC/MIC) is greater than 100, as is most commonly obtained with administration of the standard dosage of linezolid 600 mg twice daily. A wide tissue distribution, including the CNS and respiratory tract, nearly linear pharmacokinetics and good tolerability are additional characteristics of linezolid. However, variability in the drug pharmacokinetics associated with clinical conditions (e.g. sepsis, burn injuries, end-stage renal disease, cystic fibrosis), haemodialysis and/or young age may lower the T>MIC and the AUC/MIC ratio, thus impairing both antibacterial activity and prevention of mutants. In most cases, changes in the dosage or in the schedule of administration (e.g. an additional [third] daily dose) may improve the effectiveness of linezolid. It is worth noting that linezolid could affect its own metabolism as a result of protein synthesis inhibition in mitochondria, and this could lead to high plasma concentrations and an increased risk of non-negligible toxicities. The latter may be reported during long-term administration of linezolid or in the presence of some pathological conditions (e.g. renal disease or kidney transplantation) associated with high plasma drug concentrations. Therefore, treatment optimization should be considered a requirement for more effective and tolerable use of the drug, particularly in special populations.
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Affiliation(s)
- Antonello Di Paolo
- Division of Pharmacology and Chemotherapy, Department of Internal Medicine, 56126 Pisa, Italy.
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Moulin F, Ménager C. Le linézolide en pédiatrie. Arch Pediatr 2010; 17 Suppl 4:S133-9. [DOI: 10.1016/s0929-693x(10)70914-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Therapeutic drug monitoring of linezolid: a retrospective monocentric analysis. Antimicrob Agents Chemother 2010; 54:4605-10. [PMID: 20733043 DOI: 10.1128/aac.00177-10] [Citation(s) in RCA: 143] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The objective of the present retrospective observational study carried out in patients receiving a standard dosage of linezolid and undergoing routine therapeutic drug monitoring (TDM) was to assess the interindividual variability in plasma exposure, to identify the prevalence of attainment of optimal pharmacodynamics, and to define if an intensive program of TDM may be warranted in some categories of patients. Linezolid plasma concentrations (trough [C(min)] and peak [C(max)] levels) were analyzed by means of a high-performance liquid chromatography (HPLC) method, and daily drug exposure was estimated (daily area under the plasma concentration-time curve [AUC(24)]). The final database included 280 C(min) and 223 C(max) measurements performed in 92 patients who were treated with the fixed 600-mg dose every 12 h (q12h) intravenously (n = 58) or orally (n = 34). A wide variability was observed (median values [interquartile range]: 3.80 mg/liter [1.75 to 7.53 mg/liter] for C(min), 14.70 mg/liter [10.57 to 19.64] for C(max), and 196.08 mg·h/liter [144.02 to 312.10 mg·h/liter] for estimated AUC(24)). Linezolid C(min) was linearly correlated with estimated AUC(24) (r(2) = 0.85). Optimal pharmacodynamic target attainment (defined as C(min) of ≥2 mg/liter and/or AUC(24)/MIC(90) ratio of >80) was obtained in about 60 to 70% of cases, but potential overexposure (defined as C(min) of ≥10 mg/liter and/or AUC(24) of ≥400 mg·h/liter) was documented in about 12% of cases. A significantly higher proportion of cases with potential overexposure received cotreatment with omeprazole, amiodarone, or amlodipine. Our study suggests that the application of TDM might be especially worthwhile in about 30% of cases with the intent of avoiding either the risk of dose-dependent toxicity or that of treatment failure.
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Off-label antibiotic use in children in three European countries. Eur J Clin Pharmacol 2010; 66:919-27. [DOI: 10.1007/s00228-010-0842-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 05/12/2010] [Indexed: 11/26/2022]
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Clinical efficacy and tolerability of linezolid in pediatric patients: a systematic review. Clin Ther 2010; 32:66-88. [PMID: 20171414 DOI: 10.1016/j.clinthera.2010.01.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2009] [Indexed: 01/22/2023]
Abstract
BACKGROUND Linezolid is marketed for the treatment of severe, vancomycin-resistant infections with gram-positive bacteria in adults. Most information regarding the pharmacokinetic profile, efficacy, and tolerability of linezolid is derived from adult studies. OBJECTIVE The aim of this review was to summarize evidence regarding the use of linezolid in infants and children, focusing on the drug's clinical efficacy data and tolerability profile. METHODS A literature search was conducted of the Cochrane Library, EMBASE, and MEDLINE databases, from their inception through July 20, 2009, using the following terms: linezolid, newborn, infant, child, pediatrics, adolescent, human, clinical trial, and case report. Articles were excluded if they were redundant or not pertinent. (Articles that did not focus on the use of linezolid in children were considered not pertinent.) Bibliographies of all relevant articles were also evaluated. RESULTS Forty-seven publications regarding the use of linezolid in children were included in the review: 5 pharmacokinetic studies, 32 case reports, 6 randomized clinical trials (RCTs), 2 uncontrolled trials, 1 subanalysis of 2 published RCTs, and 1 subanalysis of published data about linezolid's tolerability. Pharmacokinetic data on linezolid use in children were derived from studies that enrolled 447 children. Plasma pharmacokinetics of linezolid in pediatric patients were found to be age dependent. Results from 6 vancomycinor cefadroxil-controlled RCTs (including 1480 children) evaluating linezolid treatment in children reported variable clinical cure rates, ranging from 75.0% to 93.2% in children with skin and skin-structure infections and from 77.5% to 90.0% in children with bacteremia or pneumonia. No significant difference in clinical cure rates between the linezolid group and the comparator group was observed in any study. The most frequently reported adverse events were diarrhea (from 3.1% to 16.8%), nausea and/or vomiting (from 2.9% to 11.9%), and thrombocytopenia (from 1.9% to 4.7%). To date, 3 cases of neuropathy have been described in children. CONCLUSIONS The reviewed pediatric studies in skin and skin-structure infections, bacteremia, or pneumonia found that linezolid was associated with high clinical cure rates (75.0%-93.2%) that did not differ significantly from those of vancomycin or cefadroxil. RCTs enrolling children with other types of infection (eg, osteomyelitis, endocarditis), as well as long-term studies, are needed to draw definitive conclusions about linezolid's efficacy and tolerability in pediatric patients. Careful monitoring for adverse events and possible linezolid resistance continues to be essential.
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