Determinants of fibroblast growth factor-23 and parathyroid hormone variability in dialysis patients

BACKGROUND/AIMS

Treatment strategies for abnormal mineral metabolism in chronic kidney disease are largely based on achieving target ranges of biomarkers that vary considerably over time, yet determinants of their variability are poorly defined.

METHODS

Observational study including 162 patients of three dialysis cohorts (peritoneal dialysis, n = 78; hemodialysis, n = 49; hemodiafiltration, n = 35). Clinical and biochemical determinants of parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF23) variability were analyzed in the peritoneal dialysis cohort. All cohorts were used for comparison of PTH and FGF23 intra-subject variability (intra-class correlation), and their intra-subject variability in different modes of dialysis was explored.

RESULTS

High PTH variability was independently associated with lower 25-hydroxyvitamin D concentration and factors of lipid and glucose metabolism, whereas high FGF23 variability was mainly associated with lower baseline serum phosphorous. These results were consistent in multivariate and sensitivity analyses. The intra-subject variability of FGF23 was lower than for PTH irrespective of dialysis mode.

CONCLUSIONS

Baseline vitamin D status and serum phosphorous are independent determinants of the longitudinal variation in PTH and FGF23, respectively. The clinical utility of FGF23 measurement remains unknown, yet it appears favorable based on its greater temporal stability than PTH in dialysis patients.

Elevation of urinary liver-type fatty acid-binding protein as predicting factor for occurrence of contrast-induced acute kidney injury and its reduction by hemodiafiltration with blood suction from right atrium

Although contrast-induced acute kidney injury (CI-AKI) has a great impact on patients' prognosis, few data exist regarding predictors of CI-AKI in patients with severe renal dysfunction who have undergone contrast angiography. Therefore, we prospectively studied 25 patients with renal dysfunction, which was defined as the estimated glomerular filtration rate (eGFR) level <45 ml/min/1.73 m(2), undergoing coronary angiography (CAG) or percutaneous coronary intervention (PCI). We performed hemodiafiltration with blood suction from the right atrium (RA-HDF). The mean level of urinary liver-type fatty acid-binding protein (L-FABP) at baseline was significantly higher in the CI-AKI group than in the non-CI-AKI group (59.8 ± 45.6 vs 13.4 ± 11.9 μg/gCr, P = 0.0003). Multivariate regression analysis demonstrated that baseline urinary L-FABP was an independent significant predictor of CI-AKI (β = 0.741, P = 0.013). Receiver-operating characteristic analysis showed that baseline urinary L-FABP exhibited 100 % sensitivity and 81.8 % specificity for predicting CI-AKI when the cutoff value was defined as 19.0 μg/gCr. Interestingly, the incidence of CI-AKI after CAG or PCI was reduced in the RA-HDF group in a comparison with 41 control patients (12 % vs 27 %) with eGFR level <45 ml/min/1.73 m(2) who underwent PCI before the introduction of RA-HDF. In conclusion, baseline L-FABP levels can be a predictor for occurrence of CI-AKI. We suggest that RA-HDF may prevent the development of CI-AKI in patients with severe renal dysfunction undergoing coronary procedures, although further large-scale prospective study is necessary to confirm our conclusions.

Haemodiafiltration results in similar changes in intracellular water and extracellular water compared to cooled haemodialysis

BACKGROUND/AIMS

Intradialytic hypotension is the most common complication of modern day haemodialysis (HD). Convective modalities, including haemodiafiltration (HDF) are reported to result in greater cardiovascular stability compared to standard HD, which has been suggested to be due to improved solute transport between compartments. We therefore investigated the effect of treatment on body water by bioimpedance.

METHODS

We measured the change in extracellular water (ECW) and intracellular water (ICW) in 263 outpatients attending for HD using cooled dialysate and 134 patients for HDF.

RESULTS

Patient cohorts were matched for demographics, dialysate composition, ultrafiltration rate, and session duration. The fall in systolic blood pressure following HD was -11.8 mm Hg (-25.3 to 2.3) and not different from that following HDF -12 mm Hg (-27 to 6). Similarly there were no differences in pretreatment serum sodium and dialysate sodium gradient [HD 1 mmol/l (-1 to 3) vs. HDF 2 mmol/l (1 to 4)], or change in serum sodium posttreatment [HD 0 mmol/l (-2 to 2) vs. HDF 1 mmol/l (-1 to 3)]. There were no differences in ICW or ECW pretreatment, and following treatment the reduction in ICW and ECW did not differ [ICW HD -3.5% (-5.7 to -1.8) vs. -4.1% (-6.0 to -1.7), ECW HD -7.1% (-9.4 to -4.7) vs. HDF -7.1% (-9.7 to -4.9)].

CONCLUSION

We were unable to demonstrate any advantage for HDF over HD using cooled dialysate in terms of changes in blood pressure during a treatment session, or differences in the relative changes in ICW or ECW volumes.

Effects of hemodiafiltration and high flux hemodialysis on nerve excitability in end-stage kidney disease

OBJECTIVES

Peripheral neuropathy is the most common neurological complication in end-stage kidney disease. While high flux hemodialysis (HFHD) and hemodiafiltration (HDF) have become the preferred options for extracorporeal dialysis therapy, the effects of these treatments on nerve excitability have not yet been examined.

METHODS

An observational proof-of-concept study of nerve excitability and neuropathy was undertaken in an incident dialysis population (n = 17) receiving either HFHD or HDF. Nerve excitability techniques were utilised to assess nerve ion channel function and membrane potential, in conjunction with clinical assessment and standard nerve conduction studies. A mathematical model of axonal excitability was used to investigate the underlying basis of the observed changes. Nerve excitability was recorded from the median nerve, before, during and after a single dialysis session and correlated with corresponding biochemical markers. Differences in nerve excitability were compared to normal controls with longitudinal follow-up over an 18 month period.

RESULTS

Nerve excitability was performed in patient cohorts treated with either HFHD (n = 9) or online HDF (n = 8), with similar neuropathy status. Nerve excitability measures in HDF-treated patients were significantly closer to normal values compared to HFHD patients obtained over the course of a dialysis session (p<0.05). Longitudinal studies revealed stability of nerve excitability findings, and thus maintenance of improved nerve function in the HDF group.

CONCLUSIONS

This study has provided evidence that nerve excitability in HDF-treated patients is significantly closer to normal values prior to dialysis, across a single dialysis session and at longitudinal follow-up. These findings offer promise for the management of neuropathy in ESKD and should be confirmed in randomised trials.

Acute phlegmonous esophagitis as a rare but threatening complication of chemoradiotherapy: report of a case

Phlegmonous infection involving the digestive tract has been reported to have a poor prognosis. However, the pathogenesis and clinical features of acute phlegmonous esophagitis have remained unclear due to the rarity of the disease. We herein report a case of acute phlegmonous esophagitis that showed a fulminant course during chemoradiotherapy for uterine cancer. The patient developed septic shock 10 h after postprandial nausea and vomiting, and a computed tomographic scan showed diffuse thickening of the esophageal wall. Severe leukopenia that was refractory to the administration of granulocyte colony-stimulating factor persisted during the first few days. The patient fortunately survived after intensive treatment. The acute phlegmonous esophagitis of the present case might have been evoked and worsened by chemoradiotherapy due to its emetic and myelosuppressive adverse effects, respectively. Although its incidence is extremely rare, acute phlegmonous esophagitis may occur as a life-threatening complication of chemoradiotherapy.

Modifications in relaxin's serum levels during acetate-free biofiltration (AFB): only a new biomarker?

AIMS

We evaluated relaxin's behaviour during a haemodialytic session and the effects of its intradialytic variability on blood pressure.

METHODS

We enrolled 25 patients and evaluated relaxin's levels during a haemodialytic session. We also dosed interdialytic relaxin and enrolled 10 healthy subjects and 16 patients with III stage chronic renal failure as controls.

RESULTS

Haemodialyzed patients have relaxin's baseline concentrations higher than healthy controls, but lower than chronic patients. During the treatment, relaxin is removed; it increases again throughout the interdialytic phase. Furthermore, relaxin's pre- haemodialytic concentration positively and significantly correlates with systolic, diastolic, and mean BP; such correlations disappear at the end of the treatment.

CONCLUSION

Relaxin's removal during the treatment may intervene in the pathogenesis of intradialytic hypertension. Hence, relaxin could be not only a new biomarker but also an active player in the intradialytic variations of blood pressure.

[The use of extracorporeal life support and continuous venovenous haemodiafiltration in severe angiotensin converting enzyme inhibitor, calcium channel bloker and beta-blocker multidrug intoxication]

Extracorporeal membrane oxygenation (ECMO) is an established method of treatment for extremely severe respiratory failure (ARDS, acute respiratory distress syndrome), for mechanical circulatory support after cardiac surgery as well as advanced resuscitation technique in specific cases. Severe multidrug poisoning causing an acute cardiovascular insufficiency combines all of these indications. We report a case of multiple drug poisoning: ACE inhibitor (ACE-I), beta-blockers and calcium channel blockers. Acute heart failure and multiorgan failure, have been successfully cured with the concomitant use of ECMO, hemodiafiltration and oscillatory ventilation.

[Echinocandins: searching for differences. The example of their use in patients requiring continuous renal replacement therapy]

The echinocandins have a growing role in the treatment of fungal infections because of their novel mechanism of action. This is reflected in recently published management guidelines, but available in vitro data, animal studies, and clinical studies do not clearly differentiate the three agents in class. Comparative clinical efficacy among agents within the class, pharmacokinetic profiles in special populations, pharmacoeconomics justifications, and place in therapy have been largely unanswered. They share many common properties but marketing strategies of drug manufacturers are engaged in product differentiation. Although exist similarities in the pharmacokinetic (PK) profiles of the echinocandins, limited data have been published regarding their pharmacokinetics in continuous renal replacement therapy (CRRT) patients. The pharmacokinetics of drug removal in critically ill patients receiving CRRT is very complex, with multiple variables affecting clearance. This review outlines the basic principles that determine whether a dose adjustment is required. Two studies with data on PK parameters of micafungin and anidulafungin in CRRT patients have been published and are compared following that basic principles in the review.

Applying sodium profile with or without ultrafiltration profile failed to show beneficial effects on the incidence of intradialytic hypotension in susceptible hemodilaysis patients

INTRODUCTION

Intra-dialytic hypotension (IDH) is a common complication during hemodialysis (HD) treatment. Previous studies have reported that modulating dialysate sodium concentration combined or not with modulation of ultrafiltration (UF) rate may reduce the incidence of IDH. The aim of the present study was to evaluate the effect of sodium and UF profiles on the occurrence of intra-dialytic complications and dialysis quality.

METHODS

From a total of 64 patients, we selected 18 patients who suffered from recurrent IDH. Every patient received ten HD sessions utilizing each of the following treatments: (1) CONTROL: constant sodium concentration and UF rates. (2) Sodium and UF profiles: a linearly decreasing sodium concentration combined with a linearly decreasing UF rate. (3) Sodium profile: decreasing sodium concentration with constant UF rate.

RESULTS

Fourteen patients completed the study protocol. The incidence of IDH, mean inter-dialytic weight gain and the delivered dialysis dose were not different between the three treatments. However, symptomatic episodes of IDH were more commonand pre-dialysis systolic blood pressure was higher during the second and third treatment modalities compared to controls. Isolated sodium profile was associated with more malaise and less achievement of target session duration compared to the other two treatments. Isolated sodium profile was associated with less achievement of target UF while combined sodium and UF profiles were associated with more achievement of target UF compared to controls.

CONCLUSION

Our results indicate that sodium profile with or without UF profile does not have a beneficial effect on the incidence of IDH, achievement of target session duration or the delivered dialysis dose. Keywords : Sodium Profile; Ultrafiltration; Intradialytic Complications.

[Ultrafiltration in heart failure]

In patients with heart failure fluid overload is clinically evident as systemic and/or pulmonary congestion, and represents a key issue in the therapeutic approach to the syndrome. Ultrafiltration, obtained by dedicated machines or standard dialysis machines (isolated ultrafiltration), or by the use of the peritoneal membrane (peritoneal ultrafiltration), has been recently proposed for fluid overload correction. This review is aimed at illustrating the operative background, safety, efficacy and cost issues of the different ultrafiltration modalities in heart failure. We retrieved all full-text non-duplicated articles documenting clinical studies on ultrafiltration in heart failure and describing patient characteristics, ultrafiltration procedures, renal outcome and adverse effects, by searching MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials up to December 31, 2011, with the terms ''heart failure'' and ''ultrafiltration OR hemofiltration'' and ''heart failure'' and "peritoneal dialysis". Isolated ultrafiltration can be considered potentially safe for the heart and the kidney in heart failure, and is efficacious for fluid overload removal. However, the available evidence does not support its widespread use as a substitute for conventional diuretic therapy. Isolated ultrafiltration should be employed neither as a quicker way to achieve mechanical diuresis nor as a remedy for an apparently inadequate response to conventional diuretic therapy. Peritoneal ultrafiltration is a promising ultrafiltration procedure that can be safely and successfully performed in heart failure; however, also in this case larger-scale randomized controlled trials are needed. The available evidence supports the concept of reserving ultrafiltration modalities for selected patients with advanced heart failure and true diuretic resistance, as part of a more integrated strategy aimed at fluid overload control.

Monitoring of fluconazole in serum of patients undergoing hemodiafiltration by solid-phase extraction and high-performance liquid chromatography with ultraviolet detection

A high-performance liquid chromatographic assay for monitoring the antifungal drug fluconazole in human serum was developed using a C18 reversed-phase column with isocratic elution. The method involved sample clean-up by solid-phase column extraction, and subsequent analysis required only 14 min per sample for separation and quantitation. The assay was precise, with intra- and inter-assay relative standard deviations of < or = 1.5% and < or = 3.1%. The minimum detectable concentration of fluconazole was 0.3 nmol/ml. This assay has the advantage of minimizing the risk of interference from co-administered drugs to critically ill patients undergoing hemodiafiltration.

[Kidney and bone update : the 5-year history and future of CKD-MBD. Treatment for dialysis-related amyloidosis update]

Dialysis-related amyloidosis (DRA) is a serious complication in patients undergoing long-term dialysis treatment. Deposited β(2)-microglobulin-related amyloid induces various osteoarticular disorders. The pathogenetic interaction of DRA with chronic kidney disease-minenal bone disorder (CKD-MBD) is still unclear, while clinical managements for both osteoarticular disorder and DRA is commonly required in dialysis patients. Recently, practical guidelines for DRA are published in Japan. Those make possible to assess DRA with not only pathological examination but also clinical manifestations, such as carpal tunnel syndrome, destructive spondyloarthropathy, joint pains, and so on. Treatments for DRA include hemodialysis with biocompatible high-flux dialysis membrane and/or ultrapure dialysate, hemodiafiltration, and β(2)-microglobulin adsorbent column. Recent studies suggested that these treatments have efficacy on the onset and severity of DRA, even mean age in patients are getting older with long term dialysis treatment.

Dialysis adequacy today: a European perspective

The need to improve haemodialysis (HD) therapies and to reduce cardiovascular and all-cause mortality frequently encountered by dialysis patients has been recognized and addressed for many years. A number of approaches, including increasing the frequency versus duration of treatment, have been proposed and debated in terms of their clinical efficacy and economic feasibility. Future prescription of dialysis to an expanding end-stage chronic kidney disease (CKD-5D) population needs a re-evaluation of existing practices while maintaining the emphasis on patient well-being both in the short and in the long term. Efficient cleansing of the blood of all relevant uraemic toxins, including fluid and salt overload, remains the fundamental objective of all dialysis therapies. Simultaneously, metabolic disorders (e.g. anaemia, mineral bone disease, oxidative stress) that accompany renal failure need to be corrected also as part of the delivery of dialysis therapy itself. Usage of high-flux membranes that enable small and large uraemic toxins to be eliminated from the blood is the first prerequisite towards the aforementioned goals. Application of convective therapies [(online-haemodiafiltration (OL-HDF)] further enhances the detoxification effects of high-flux haemodialysis (HF-HD). However, despite an extended clinical experience with both HF-HD and OL-HDF spanning more than two decades, a more widespread prescription of convective treatment modalities awaits more conclusive evidence from large-scale prospective randomized controlled trials. In this review, we present a European perspective on the need to implement optimal dialysis and to improve it by adopting high convective therapies and to discuss whether inertia to implement these practice patterns may deprive patients of significantly improved well-being and survival.

[Peculiarities of treatment of patients, suffering postoperative peritonitis, complicated by abdominal sepsis]

In 2001-2011 yrs 241 patients, 18-80 years old, including 148 (61.4%) men and 93 (38.6%) women, were treated in the clinic f postoperative peritonitis. In 156 (64.7%) patients abdominal sepsis was diagnosed. In 74 (83%) patients a puncture-draining interventions were performed under ultrasonographic control for local postoperative peritonitis, and relaparotomy - in 15 (16.9%). In 18 (11.8%) patients, suffering extended peritonitis, miniinvasive technologies were applied. For extracorporal detoxication in 96 (40%) patients the intermitting veno-venous hemodiafiltration was conducted as well as plasmapheresis, peritoneal dialysis. As a result of polyorgan insufficiency development 34 (14.1%) patients died, of them after miniinvasive interventions - 5 (5.4%).

Effect of blood flow rate on internal filtration in a high-flux dialyzer with polysulfone membrane

Internal filtration/backfiltration (IF/BF) of a dialyzer depends on several parameters. This study evaluated the effect of the blood flow rate (Q (B)) on the internal filtration flow rate (Q (IF)) measured using Doppler ultrasonography for a high-flux dialyzer with a polysulfone membrane, APS-15E. In an in vitro study, bovine blood was circulated through the dialyzer, at a Q (B) of 100-350 mL/min. The clearances (CL) of creatinine, β(2)-microglobulin, and α(1)-microglobulin were then investigated. Q (IF) increased with the Q (B) value. A good correlation was obtained between Q (IF) and the pressure difference between the pressures at the inlet of the blood compartment and the pressure at the outlet of the dialysate compartment. The creatinine CL values strongly depended on Q (B) because molecular diffusion was dominant. The β(2)-microglobulin CL also depended on Q (B), because its removal rate seemed to be affected by both diffusive and convective transport caused by the IF/BF. An extremely low CL value was obtained for α(1)-microglobulin because of its low diffusivity and membrane fouling induced by proteins plugging the membrane. In conclusion, the IF/BF in the dialyzer strongly depends on Q (B). Furthermore, the dependence of the solute clearance on Q (B) decreased with increasing molecular size of the solute because of the decrease in diffusivity through the membrane.

Multidisciplinary mechanical supports improve outcome in a shock patient with cardiac amyloidosis: a case report

Shock patients with restrictive cardiomyopathy due to cardiac amyloidosis are refractory to medical treatment. Here, we report a case of early initiation of intra-aortic balloon pumping (IABP) in a patient with cardiac amyloidosis who developed postoperative shock. Continuous hemodiafiltration was also applied to control circulating fluid volume. The mechanical treatments allowed reduction of the doses of catecholamine and diuretics and resulted in full recovery. It is reasonable to initiate IABP and hemofiltration dialysis during the early stages for the appropriate control of hemodynamics and fluid in shock patients with cardiac amyloidosis.

[Severe paracetamol poisoning complicated with liver and renal failure--case report and review of literature]

Paracetamol is a widely known over-the-counter analgesic and antipyretic which, in acute poisoning usually causes liver damage, and less commonly damage to the kidney, heart, and pancreas. In the present paper we report a case of acute suicidal paracetamol intoxication complicated by acute hepatic and renal failure. The discussion covers the pathogenesis, clinical course, and treatment of acute renal failure in the course of paracetamol poisoning.

CASE REPORT

A thirty-four-year-old woman was admitted to hospital in the second day after ingestion of nearly 17 g of acetaminophen. During admission to the hospital, the maximum values of transaminases (AST 19 350 U/L, ALT 11 760 U/L) were found; they have gradually normalized over the next few weeks. Sequentially monitored serum creatinine showed an upward trend, reaching a value of 588 micromol/L in the fifth day after drug ingestion. The patient underwent 1 haemodiafiltration and 4 haemodialysis treatments resulting in an improvement in renal function.

CONCLUSIONS

In acute acetaminophen poisoning, in addition to standard monitoring of liver function, the monitoring of kidney function is necessary because of the risk of acute renal failure due to acute tubular necrosis. Kidney damage is likely to be transient and generally will not need long-term renal replacement therapy.