Joanne M. Bargman

Randomized, Controlled Trial of Glucose-Sparing Peritoneal Dialysis in Diabetic Patients

Glucose-containing peritoneal dialysis solutions may exacerbate metabolic abnormalities and increase cardiovascular risk in diabetic patients. Here, we examined whether a low-glucose regimen improves metabolic control in diabetic patients undergoing peritoneal dialysis. Eligible patients were randomly assigned in a 1:1 manner to the control group (dextrose solutions only) or to the low-glucose intervention group (IMPENDIA trial: combination of dextrose-based solution, icodextrin and amino acids; EDEN trial: a different dextrose-based solution, icodextrin and amino acids) and followed for 6 months. Combining both studies, 251 patients were allocated to control (n=127) or intervention (n=124) across 11 countries. The primary endpoint was change in glycated hemoglobin from baseline. Mean glycated hemoglobin at baseline was similar in both groups. In the intention-to-treat population, the mean glycated hemoglobin profile improved in the intervention group but remained unchanged in the control group (0.5% difference between groups; 95% confidence interval, 0.1% to 0.8%; P=0.006). Serum triglyceride, very-low-density lipoprotein, and apolipoprotein B levels also improved in the intervention group. Deaths and serious adverse events, including several related to extracellular fluid volume expansion, increased in the intervention group, however. These data suggest that a low-glucose dialysis regimen improves metabolic indices in diabetic patients receiving peritoneal dialysis but may be associated with an increased risk of extracellular fluid volume expansion. Thus, use of glucose-sparing regimens in peritoneal dialysis patients should be accompanied by close monitoring of fluid volume status.

Noninfectious complications of peritoneal dialysis

The steady decrease in the incidence of bacterial peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD) has allowed us to focus on noninfectious complications of peritoneal dialysis. Many of the complications result from the increased intra-abdominal pressure caused by the instillation of litres of fluid into a cavity which usually holds much less. Other complications arise because of the long-term effect of peritoneal dialysate directly on the mesothelial cells with which it has almost continuous contact, and more indirectly from the long-term metabolic consequences of this solution on the body’s physiochemistry. This chapter will address these and other complications of peritoneal dialysis.

Two icodextrin exchanges per day in peritoneal dialysis patients with ultrafiltration failure: one center's experience and review of the literature

BackgroundAt present, only one exchange of an icodextrin-based solution is recommended to increase peritoneal ultrafiltration (UF) during long-dwell exchanges in peritoneal dialysis (PD) patients with impaired UF.AimTo review our experience with two icodextrin exchanges per day on net UF and body weight in PD patients with poor UF.MethodsData were analyzed on nine patients with poor UF on chronic PD who were given two icodextrin exchanges per day for 6xa0months and had various clinical and biochemical parameters assessed monthly.ResultsAdministration of icodextrin twice daily reduced the body weight in six of nine patients by an average of 2.9xa0±xa01.2xa0kg, a reduction that was maintained throughout the study; two patients gained 0.5xa0kg; and, in one patient, the measurements were inadequate. Mean blood pressure was reduced. Mean serum creatinine increased slightly. Serum sodium levels decreased from a mean baseline level of 134xa0±xa03 to 132xa0±xa04xa0mmol/L at three and six months. Among the diabetics in this group, average daily insulin requirements were 44xa0±xa035 units/day at baseline and 40xa0±xa023 units/day after 6xa0months. Hb1Ac levels remained stable throughout the study period.ConclusionThe use of two icodextrin exchanges per day reduced body weight in six of the nine patients and appeared to be safe. Long-term prospective studies are needed to assess the contribution of twice-daily icodextrin to the management of peritoneal dialysis patients with ultrafiltration failure and its long-term safety.

Clinical, Biochemical, and Pathological Features in a Patient with Plasma Cell Dyscrasia and Fanconi Syndrome

Multiple myeloma is associated with a wide array of renal diseases that include myeloma cast nephropathy, monoclonal immunoglobulin deposition disease, amyloidosis, cryoglobulinemia, tubular dysfunction, pyelonephritis, nephrocalcinosis, urate nephropathy, and infiltration by atypical plasma cells (or myeloma cells). Filtered immunoglobulin light chains may affect both the distal and, more frequently, the proximal tubule. Tubular abnormalities in patients with plasma cell dyscrasia may be more frequent than previously thought. A patient with a plasma cell dyscrasia is described, who presented with biochemical features consistent with Fanconi syndrome. Immunoelectron microscopy performed on the renal biopsy confirmed the presence of kappa light chain immunoglobulin in intracytoplasmic crystals in proximal tubular epithelial cells. This report is one of a few demonstrating the presence of light-chain immunoglobulin in intratubular crystals in a human renal biopsy obtained from a patient with a plasma cell dyscrasia and Fanconi syndrome.

Complications other Than Peritonitis or those Related to the Catheter and the Fate of Uremic Organ Dysfunction in Patients Receiving Peritoneal Dialysis

This chapter is divided into two sections. In the first, we will discuss the complications of peritoneal dialysis other than peritonitis and those related to the catheter, which are discussed elsewhere in this book. In the second part of this chapter, we will discuss the fate or ‘unnatural history’ of uremic organ dysfunction in patients receiving peritoneal dialysis. Inclusion of some topics into one or the other section has been arbitrary, since it is not clear to what extent the condition being discussed is a complication of uremia or dialysis itself.

Calciphylaxis precipitated by ultraviolet light in a patient with end-stage renal disease secondary to systemic lupus erythematosus

Calciphylaxis is a rare and severe calcification syndrome described mainly in patients with end-stage renal disease (ESRD) undergoing dialysis or with a renal transplant. This life-threatening condition is characterized by the abrupt onset of painful ischemic skin ulcers and necrosis. Secondary local and systemic infection may supervene and, without timely and appropriate interventions, calciphylaxis may be fatal. A precipitant or challenging agent is believed to be necessary to initiate the process. We describe a case of a woman with ESRD receiving continuous ambulatory peritoneal dialysis who developed calciphylaxis in the setting of severe hyperparathyroidism after receiving UV photoradiation therapy. We suggest that the UV light served as the challenging agent in the precipitation of this devastating condition.

Regarding ‘Calcium channel blocker–induced chylous ascites in peritoneal dialysis’

To the Editor: We appreciate the report by Tsao and Chen 1 about chylous ascites associated with the use of calcium channel blockers in a patient on peritoneal dialysis. The authors list other causes of chyloperitoneum, including neoplasia, nephrotic syndrome, and congenital abnormalities of the lymphatic system. We would like to bring to the readers’ attention another disease associated with chylous ascites that may be encountered in patients on peritoneal dialysis: systemic lupus erythematosus. 2 It has been suggested that mesenteric inflammation from the lupus can lead to lymphatic obstruction and consequent chyloperitoneum and chylothorax. Those managing patients on peritoneal dialysis should be aware of this association between lupus and chyloperitoneum.

What are the problems with using the peritoneal membrane for long-term dialysis?

Since the development of therapy with continuous peritoneal dialysis (PD), glucose has been the principal osmole used to effect ultrafiltration. In decades of use, glucose has proved to be safe and effective. However, there is concern that, in the long-term patient, exposure of the peritoneal membrane to supraphysiologic concentrations of this solute or its degradation products can lead to progressive damage and dysfunction of themembrane. In addition, as significant amounts of glucose are absorbed systemically across the peritoneum, it has been suggested that chronic glucose loading of the dialysis patient over months to years can lead to adverse consequences.

The Interaction of Dialysis Prescription and Residual Kidney Function: Yet Another Layer of Complexity

Residual kidney function in patients treated with maintenance dialysis has been recognized as an important metric for the past 3 decades, but is arguably still often overlooked. Multiple observational studies consistently show residual kidney function, as defined by small-solute clearance via the kidney, to be an independent risk factor for survival in both hemodialysis and peritoneal dialysis (PD) patients. Greater emphasis tends to be placed on residual kidney function in PD patients, given the observation that it declines more rapidly in those on hemodialysis therapy. In addition, higher residual kidney function is associated with better quality of life, including improved physical functioning and lower incidence of sleep disorders, as well as improved nutrition and reduced erythropoietin requirement. The 1996 prospective Canada-USA (CANUSA) PD Study initially suggested that higher total (peritoneal and kidney) solute clearance in PD patients was associated with an improvement in mortality. However, residual kidney function was not examined separately as a risk factor for clinical outcomes, and a reanalysis of this study questioned the assumption that kidney and peritoneal clearances are comparable. Specifically, the reanalysis determined that the predictive power for mortality in PD patients was solely attributable to residual kidney function, corresponding to a 12% lower relative risk for death for each 5-L/wk/1.73 m greater glomerular filtration rate (GFR). ADEMEX, the Randomized Adequacy of PD in Mexico trial, also highlighted that higher peritoneal solute clearance did not confer a survival benefit and that residual kidney function was responsible for survival gains. These studies led us to the suggestion that kidney clearance is not equivalent to that occurring by the peritoneum. Possible reasons may include enhanced middlemolecule clearance and salt removal via residual kidney function and an intrinsic anti-inflammatory effect of functioning kidneys. Consequently, every effort should be made to preserve residual kidney function, and additional research to clarify risk factors precipitating its decline should be welcomed. In this issue of the AJKD, Yan et al present a prospective randomized controlled trial examining the rate of residual kidney function decline in continuous ambulatory PD (CAPD) patients comparing 3 versus 4 daily exchanges using glucose-based dialysate. This specific comparison has not previously been investigated, so the study provides a useful and novel insight.

Pediatric Lupus Nephritis

Review the epidemiology, pathogenesis, and clinical-histological features of lupus nephritis.