QT Interval Shortening With Isavuconazole: In Vitro and In Vivo Effects on Cardiac Repolarization.

The effects of isavuconazole (active moiety of isavuconazonium sulfate) on cardiac ion channels in vitro and cardiac repolarization clinically were assessed in a phase I, randomized, double-blind study in healthy individuals who received isavuconazole (after 2-day loading dose), at therapeutic or supratherapeutic doses daily for 11 days, moxifloxacin (400 mg q.d.), or placebo. A post-hoc analysis of the phase III SECURE trial assessed effects on cardiac safety. L-type Ca2+ channels were most sensitive to inhibition by isavuconazole. The 50% inhibitory concentrations for ion channels were higher than maximum serum concentrations of nonprotein-bound isavuconazole in vivo. In the phase I study (n = 161), isavuconazole shortened the QT interval in a dose- and plasma concentration-related manner. There were no serious treatment-emergent adverse events; palpitations and tachycardia were observed in placebo and supratherapeutic isavuconazole groups; no cardiac safety signals were detected in the SECURE study (n = 257). Isavuconazole was associated with a shortened cardiac QT interval.

The effect of mirabegron on patient-related outcomes in patients with overactive bladder: the results of post hoc correlation and responder analyses using pooled data from three randomized Phase III trials.

PURPOSE: To understand how improvements in the symptoms of overactive bladder (OAB) seen with the ß3-adrenoceptor agonist mirabegron 50 mg, correlate with patient experience as measured by validated and standard patient-reported outcomes (PROs), and to identify whether there is overall directional consistency in the responsiveness of PROs to treatment effect. METHODS: In a post hoc analysis of pooled data from three randomized, double-blind, placebo-controlled, 12-week Phase III trials of mirabegron 50 mg once daily, responder rates for incontinence frequency (≥50 % reduction in incontinence episodes/24 h from baseline to final visit), micturition frequency (≤8 micturitions/24 h at final visit), and PROs [minimally important differences in patient perception of bladder condition (PPBC) and subsets of the overactive bladder questionnaire (OAB-q) measuring total health-related quality of life (HRQoL), and symptom bother] were evaluated individually and in combination. RESULTS: Mirabegron 50 mg demonstrated greater improvement from baseline to final visit than placebo for each of the responder analyses, whether for individual objective and subjective outcomes or combinations thereof. These improvements versus placebo were statistically significant for all double and triple responder analyses and for all single responder analyses except PPBC. PRO measurements showed directional consistency and significant correlations, and there were also significant correlations between objective and subjective measures of efficacy. CONCLUSIONS: The improvements in objective measures seen with mirabegron 50 mg translate into a meaningful clinical benefit as evident by the directional consistency seen in HRQoL measures of benefit.

Proarrhythmic safety of repeat doses of mirabegron in healthy subjects: a randomized, double-blind, placebo-, and active-controlled thorough QT study.

Potential effects of the selective ß(3)-adrenoceptor agonist mirabegron on cardiac repolarization were studied in healthy subjects. The four-arm, parallel, two-way crossover study was double-blind and placebo- and active (moxifloxacin)-controlled. After 2 baseline ECG days, subjects were randomized to one of eight treatment sequences (22 females and 22 males per sequence) of placebo crossed over with once-daily (10 days) 50, 100, or 200 mg mirabegron or a single 400-mg moxifloxacin dose on day 10. In each period, continuous ECGs were recorded at two baselines and on the last drug administration day. The lower one-sided 95% confidence interval for moxifloxacin effect on QTcI was >5 ms, demonstrating assay sensitivity. According to ICH E14 criteria, mirabegron did not cause QTcI prolongation at the 50-mg therapeutic and 100-mg supratherapeutic doses in either sex. Mirabegron prolonged QTcI interval at the 200-mg supratherapeutic dose (upper one-sided 95% CI >10 ms) in females, but not in males.

Glucose sparing in peritoneal dialysis: implications and metrics.

Glucose sparing is a central component of modern peritoneal dialysis therapy, necessary to reduce the trade-offs of the therapy in terms of membrane protection and alleviation of systemic consequences. We present a detailed exploration of a metric for this approach in the form of the index of ultrafiltration efficiency, that we propose as a guide for designing therapeutic regimens and for the development of new dialysis solutions. Based on insights from exploration of ultrafiltration efficiency with various dialysis solutions, we propose an approach to optimizing dialysis prescription.

Patient and technique survival on peritoneal dialysis in patients with failed renal allograft: a case-control study.

Failed renal allograft is becoming one of the most frequent causes of dialysis initiation in countries with developed transplant programs. The majority of patients initiate hemodialysis (HD) as their next renal replacement modality and concerns about the success of peritoneal dialysis (PD) in this patient population has been expressed. We evaluated patient and technique outcome in a cohort of 494 patients in the United States who initiated PD after a failed renal allograft in the years 2000-2003, and compared the outcomes to those of two case-matched groups: patients new to dialysis or patients transferred from HD who started PD during the same period. Patients starting PD after a failed allograft had patient survival and technique survival similar to case-matched controls. Transplantation was lower in patients with failed allograft than controls. The high success of PD in patients with failed allograft suggests that it is beneficial to utilize this modality more frequently in this patient group than current practice.

Peritoneal dialysis in the US: evaluation of outcomes in contemporary cohorts.

Secular trends in dialysis therapy delivery require a frequent re-examination of outcomes in patients on renal replacement modalities. We examined four large cohorts of patients initiating peritoneal dialysis (PD) in 2000-2003 (total of >40 000 patients) to ascertain trends in patient outcomes, technique success, and predictors of both parameters of interest. Age, end-stage renal disease vintage, and diabetes were clear predictors of patient survival. Technique success was higher in patients on automated PD than in patients on continuous ambulatory PD. Center size was a powerful predictor of technique success. We conclude that the current state of PD in the United States is characterized by improving patient outcomes, higher technique success, and a predominance of use of cycler-based therapy. Several opportunities for improving technique success amenable to practice interventions have been identified.

Microbiology and outcomes of peritonitis in North America.

A proper understanding of the patterns of occurrence of infectious complications in patients on peritoneal dialysis (PD) is crucial to lay the foundation for interventions directed at the major causes and predisposing factors. The present work is an initial report of a survey based on a large representative database of the infectious complications of PD. Gram-positive organisms accounted for 62% of peritonitis episodes in the US and 61% of these episodes in Canada. Gram-negative organisms accounted for 20.5% of episodes in the US and 23.6% of episodes in Canada. The peritoneal catheter was removed in 18% of the episodes in the US and 16% in Canada. Less than 4% of the episodes resulted in death. Gram-positive organisms accounted for the majority of exit-site infections in the US (69%) and Canada (76%). Gram-negative organisms accounted for a third of exit-site infections and among Gram-negative organisms Pseudomonas was the overwhelmingly dominant organism. The microbiology of exit-site infections revealed the expected representation of Gram-positive organisms. An important finding, however, is the significantly high contribution of Gram-negative organisms. Our findings can inform future guideline development and suggest that similar endeavors be undertaken in other parts of the world.

Profiles of automated peritoneal dialysis prescriptions in the US 1997-2003.

Automated peritoneal dialysis (PD) is the dominant mode of delivery of PD in the US. Information about actual prescribing patterns has been limited. The present study examines cycler prescription use in large cohorts during the years 1997, 2000, and 2003. We observed trends consisting of increasing fill volumes, increasing time on cycler, lowering of the number of cycles, and a shift in the reason for utilization of tidal therapy. Monitoring of practice patterns is beneficial in identifying opportunities for practice enhancement. The findings of the present survey demonstrate trends that approach standard recommendations of the benefits of increasing fill volume whereas paying close attention to dwell time as a balance between cycle number and therapy duration. Furthermore, this survey shows that the cycler represents a flexible method to personalize PD therapy.

Pediatric peritoneal dialysis training: characteristics and impact on peritonitis rates.

OBJECTIVE: Peritonitis is the leading cause of technique failure in pediatric patients on peritoneal dialysis. A survey was developed to determine what impact, if any, training practices and staffing patterns have on peritonitis rates in pediatric patients. DESIGN: A survey developed by the International Society for Peritoneal Dialysis Advisory Committee on Peritonitis Management in Pediatric Patients. PATIENTS: The survey was distributed to 168 centers and was completed by 76 (45%) centers. A total of 597 children younger than 21 years of age received peritoneal dialysis in these centers. RESULTS: The peritonitis rate was significantly lower (1 episode/19.9 months vs 1 episode/13.5 months; p < 0.05) in programs characterized by larger patient numbers (> or = 15 patients vs < 15 patients) and longer training time dedicated to theory and practical/technical skills (p < 0.01). CONCLUSION: Peritoneal dialysis training is an important factor that influences the rate of peritonitis. The results of this survey reinforce the value of the time committed to this effort.

Clinical benefits and tolerability of increased fill volumes in Japanese peritoneal dialysis patients.

BACKGROUND: Increasing fill volume is an effective means of improving clearances in patients on peritoneal dialysis (PD). Since Japanese PD patients are physically smaller than their Western counterparts, there is some concern that PD patients in Japan may be unable to tolerate larger fill volumes. OBJECTIVE: To determine patient tolerance and changes in solute clearance and net ultrafiltration resulting from increased fill volumes in Japanese patients on PD. DESIGN: Prospective double-blind study, randomizing patients to three different fill volumes (2.5% dextrose solution: 1.5 L, 2.0 L, or 2.5 L) administered in random order on three different occasions separated by 1 week. RESULTS: Twenty-one patients with a mean age of 55.4 +/- 2.1 years and a mean body surface area of 1.66 +/- 0.03 m2 were studied. On a scale of 0 to 10, patients' mean discomfort scores were 2.14 +/- 0.59, 3.48 +/- 0.54, and 3.81 +/- 0.63 (p = 0.047) at the end of the 1.5-L, 2.0-L, and 2.5-L dwells, respectively. There were no reports of cramps or shortness of breath with any fill volume. Patients were able to correctly guess the actual fill volume for only 34 of the 63 total exchanges (54.0%). Increasing fill volume resulted in an incremental improvement in peritoneal creatinine clearance, from 3.74 +/- 0.16 to 4.49 +/- 0.21 (p < 0.001, 2.0 L vs 1.5 L) to 5.12 +/- 0.20 mL/minute (p< 0.001, 2.5 L vs 2.0 L) for 1.5-L, 2.0-L, and 2.5-L dwells, respectively. Peritoneal urea clearance also increased significantly, from 5.65 +/- 0.13 to 7.04 +/- 0.17 (p < 0.001, 2.0 L vs 1.5 L) and 8.16 +/- 0.29 mL/minute (p < 0.001, 2.5 L vs 2.0 L), with incremental increases in fill volume. Similarly, net ultrafiltration in a 4-hour dwell increased significantly with fill volume, from 255.24 +/- 24 mL with 1.5 L, to 356 +/- 24 (p < 0.004, 2.0 L vs 1.5 L) and 392 +/- 29 mL (p < 0.086, 2.5 L vs 2.0 L) in patients receiving 2.0 L and 2.5 L, respectively. CONCLUSION: Increasing the fill volume results in improvement in solute clearance and net ultrafiltration in Japanese PD patients, with minimal increase in patient discomfort. A large percentage of patients were unable to identify the actual fill volume.

Encapsulating peritoneal sclerosis: definition, etiology, diagnosis, and treatment. International Society for Peritoneal Dialysis Ad Hoc Committee on Ultrafiltration Management in Peritoneal Dialysis.

Current definitions of encapsulating peritoneal sclerosis are practical and clinically relevant. It is important to adhere to a more uniform use of the proper terminology, and it is the recommendation of the authors that EPS be adopted as the more appropriate term. The best literal definition of EPS is based on clinical-pathologic criteria. Differentiation of EPS from the general category of ultrafiltration failure is required. Further, better appreciation of the diverse pathways that can lead to the same final common clinical-pathologic picture should not be overshadowed by the requirement of uniform terminology. Incidence and prevalence of the syndrome have been defined in some large populations and a few single-center experiences. The former show an incidence of less than 1%, while higher percentages are reported in the latter. The reported increased incidence with duration on therapy requires validation. The epidemiology of the syndrome offers limited insight into its pathogenesis. A list of factors, both dialysis-related and non dialysis-related. has been accumulated. Except in a few categories where agents are clearly related to the development of EPS, the majority of the listed factors for dialysis-related BPS remain, at best, associations and at worst, simple conjecture. The same limitations that plague the issue of etiology apply in the area of pathogenesis. More basic, focused work is required. The diagnosis of EPS remains based on clinical suspicion confirmed with, primarily, radiologic findings. Pathologic confirmation is obtained in cases that come to surgery for management or for catheter removal. Radiologic studies are precise enough for confirmation, but none have been evaluated for early diagnosis for possible early intervention or prevention. Studies based on transport characteristics or effluent dialysate constituents are not useful for EPS. At present, there are no reliable predictive tests for BPS that can be used in individual patients. Therapy of BPS is based on anecdotal evidence. The possible variable etiologies and probable distinct pathways leading to the syndrome may make a uniform therapeutic approach unlikely. Further, the limited number of cases and the sporadic pattern of occurrences make therapeutic trials not readily feasible. This is distinct from the case of ultrafiltration failure, where significant advances in mechanism elucidation and rationale-based interventions have been made.

Treatment of severe systemic lupus erythematosus with high-dose chemotherapy and haemopoietic stem-cell transplantation: a phase I study.

BACKGROUND: Patients with systemic lupus erythematosus (SLE) who experience persistent multiorgan dysfunction, despite standard doses of intravenous cyclophosphamide, represent a subset of patients at high risk of early death. We investigated the safety and efficacy of immune suppression and autologous haemopoietic stem-cell infusion to treat such patients. METHODS: From 1996, we selected patients with persistent SLE despite use of cyclophosphamide. Patients underwent dose-intense immune suppression and autologous haemopoietic stem-cell (CD34) infusion. Peripheral blood lymphocytes were analysed by flow cytometry, ELISA, and T-cell-receptor spectratyping before and after transplantation. We mobilised autologous haemopoietic stem cells with 2.0 g/m2 cyclophosphamide and 10 microg/kg granulocyte colony stimulating factor daily, enriched with CD34-positive selection, and reinfused after immunosuppression with 200 mg/kg cyclophosphamide, 1 g methylprednisolone, and 90 mg/kg equine antithymocyte globulin. RESULTS: Nine patients underwent stem-cell mobilisation but two were excluded before transplantation because of infection. The remaining seven received high-dose chemotherapy and stem-cell infusion. Median time to an absolute neutrophil count higher than 0.5x10(9)/L and nontransfused platelet count higher than 20x10(9)/L was 9 days (range 8-11) and 11 days (10-13), respectively. At a median follow-up of 25 months (12-40), all patients were free from signs of active lupus. Renal, cardiac, pulmonary, and serological markers, and T cell phenotype and repertoire had normalised. INTERPRETATION: Patients remained free from active lupus and improved continuously after transplantation, with no immunosuppressive medication or small residual doses of prednisone. T-cell repertoire diversity and responsiveness was restored. Durability of remission remains to be established.

Correlation between peritoneal equilibration test and dialysis adequacy and transport test, for peritoneal transport type characterization. Mexican Nephrology Collaborative Study Group.

OBJECTIVE: The aim of this study was to analyze the correlation between the peritoneal equilibration test (PET) and the dialysis adequacy and transport test (DATT) for peritoneal transport type characterization, and the degree of patients' acceptance for each test. DESIGN: Cross-sectional, observational multicenter study. SETTING: Five referral (tertiary) dialysis centers of institutional practice. PATIENTS: The study included 107 adult continuous ambulatory peritoneal dialysis (CAPD) patients with a prescription of four exchanges of 2 L per day, irrespective of age, gender, cause of end-stage renal disease, time on dialysis, nutritional status, or residual renal function. Patients on immunosuppressive therapy and those with cancer, hepatitis B, or HIV, and those having a peritonitis episode within the previous 30 days, or three or more episodes during the previous 12 months, were excluded. MAIN MEASURES: Peritoneal transport type as classified by creatinine and urea dialysis-to-plasma (D/P) ratios by PET and DATT. RESULTS: Correlation coefficients between D/P ratios for creatinine and urea, obtained for the PET and the DATT, were 0.73 for D/P creatinine and 0.96 for D/P urea. Patients were classified into high, high-average, low-average, and low transport categories according to the mean and standard deviation of D/P creatinine values obtained from the PET at 4 hours. These values showed excellent concordance with those generated from the DATT data (alpha = 0.82, 95% confidence interval 0.67 - 0.93). Nineteen percent of patients showed discordance in their category when classified according to the PET versus the DATT. Patients' acceptance was better for the DATT than for the PET, as evaluated with a questionnaire. CONCLUSION: The DATT is an easy, inexpensive, and reliable test to assess peritoneal transport type, and it also provides information about peritoneal clearance of solutes and ultrafiltration. The DATT has better patient acceptance than the PET. Since the DATT has only been validated for patients on a fixed CAPD daily schedule of 4 x 2 L, the results should be confined only to patients receiving such a prescription.

The future of the realm: medicine and divination in ancient Syro-Mesopotamia.

The contributions of Syro-Mesopotamian cultures to the understanding of illnesses and organ functions have been sought in examination of medical and therapeutic texts. These provide a wealth of knowledge on prevalent diseases and nascent empirical therapeutics. There are, however, other sources of information relevant to this topic that have not been as thoroughly explored. Examination of representative arts, for example, provides documentations of the breadth of anatomical knowledge in these cultures. Study of the omen literature is useful in illustrating beliefs in disease etiology as well as documentation of prevalent diseases and observations on anatomical variations. In the present article we explore the various sources for information relevant to the kidney and related diseases.

Erythropoietin is produced by tubular cells of the rat kidney.

The cellular site of erythropoietin (epo) production within the mammalian kidney is still not completely understood. In the present study, we examined the expression of epo mRNA in microdissected rat nephron segments by RT-PCR after induction of epo expression with cobalt chloride. Erythropoietin mRNA was not detected in nephron segments from saline injected rats. In cobalt chloride injected animals, epo mRNA was found in the majority of samples from the cortical region of the nephron, PCT, and CAL. Medullary tubule preparations (MCT and MAL) were mostly negative for epo mRNA, and glomeruli were uniformly negative. The induction of epo transcripts in tubular cells by cobalt chloride was paralleled by stimulation of the major transport enzyme in the kidney, namely, Na-K ATPase in a tubular profile similar to that of induction of epo transcripts. These results support some earlier findings that epo gene expression in response to cobalt salt stimulation of rat kidney occurs in transporting tubular epithelial cells.