Impact of new dialysis solutions on peritonitis rates

Immune Dysfunction in Dialysis Patients—Prevention and Treatment Strategies

Immune dysfunction, resulting in infection or inflammation, or both, is closely associated with poor clinical outcome in end-stage renal disease patients. So far, no single measure can effectively address this condition, because many factors, such as uremia per se and dialysis treatment are involved in the pathogenesis. Our review focuses on currently available treatments and prevention options, and identifies future research needs.

Renal Association Clinical Practice Guideline on peritoneal dialysis in adults and children

These guidelines cover all aspects of the care of patients who are treated with peritoneal dialysis. This includes equipment and resources, preparation for peritoneal dialysis, and adequacy of dialysis (both in terms of removing waste products and fluid), preventing and treating infections. There is also a section on diagnosis and treatment of encapsulating peritoneal sclerosis, a rare but serious complication of peritoneal dialysis where fibrotic (scar) tissue forms around the intestine. The guidelines include recommendations for infants and children, for whom peritoneal dialysis is recommended over haemodialysis.Immediately after the introduction there is a statement of all the recommendations. These recommendations are written in a language that we think should be understandable by many patients, relatives, carers and other interested people. Consequently we have not reworded or restated them in this lay summary. They are graded 1 or 2 depending on the strength of the recommendation by the authors, and A-D depending on the quality of the evidence that the recommendation is based on.

The Trio Trial - A Randomized Controlled Clinical Trial Evaluating the Effect of a Biocompatible Peritoneal Dialysis Solution on Residual Renal Function

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BACKGROUND AND OBJECTIVE

Residual renal function (RRF) correlates with mortality and morbidity rates in patients receiving peritoneal dialysis (PD). We examined the effect of a biocompatible PD solution (Gambrosol Trio; Gambro Lundia AB, Lund, Sweden) with lower concentrations of glucose degradation products on rates of decline in RRF. ♦

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

Incident patients at 2 centers in Canada and 1 in Hong Kong were randomized (by minimization) in an open-label parallel group trial to receive Gambrosol Trio or standard PD solution (Dianeal; Baxter Healthcare, Mississauga, Canada) for 2 years. Primary outcome was slope of RRF. Secondary outcomes were urine volumes, fluid and nutrition indices, PD and membrane characteristics, peritonitis rates, adverse events, and PD technique survival. ♦

RESULTS

Residual renal function declined by 0.132 mL/minute/1.73 m(2)/month in 51 patients allocated to biocompatible, and 0.174 mL/minute/1.73 m(2)/month in 50 patients allocated to standard PD solution (difference 0.042 mL/minute/1.73 m(2)/month, p = 0.001). Urine volume, body mass index, normalized protein catabolic rates, and fat mass were higher; total body water, peritoneal ultrafiltration, and D/P creatinine did not differ; and serum phosphate, rates of icodextrin, and automated cycler use were lower with Gambrosol Trio use. There were more peritonitis events with Gambrosol Trio use, while PD technique survival did not differ between groups. ♦

CONCLUSIONS

The use of the biocompatible PD solution Gambrosol Trio was associated with slower rates of decline in RRF, fluid and nutrition benefits, and increased peritonitis rates.

TRIAL NUMBER

ISRCTN26252543.

The negative impact of early peritonitis on continuous ambulatory peritoneal dialysis patients

BACKGROUND

Peritonitis rate has been reported to be associated with technique failure and overall mortality in previous literatures. However, information on the impact of the timing of the first peritonitis episode on continuous ambulatory peritoneal dialysis (CAPD) patients is sparse. The aim of this research is to study the influence of time to first peritonitis on clinical outcomes, including technique failure, patient mortality and dropout from peritoneal dialysis (PD).

METHODS

A retrospective observational cohort study was conducted over 10 years at a single PD unit in Taiwan. A total of 124 patients on CAPD with at least one peritonitis episode comprised the study subjects, which were dichotomized by the median of time to first peritonitis into either early peritonitis patients or late peritonitis patients. Cox proportional hazard model was used to analyze the correlation of the timing of first peritonitis with clinical outcomes.

RESULTS

Early peritonitis patients were older, more diabetic and had lower serum levels of creatinine than the late peritonitis patients. Early peritonitis patients were associated with worse technique survival, patient survival and stay on PD than late peritonitis patients, as indicated by Kaplan-Meier analysis (log-rank test, p = 0.04, p < 0.001, p < 0.001, respectively). In the multivariate Cox regression model, early peritonitis was still a significant predictor for technique failure (hazard ratio (HR), 0.54; 95% confidence interval (CI), 0.30 - 0.98), patient mortality (HR, 0.34; 95% CI, 0.13 - 0.92) and dropout from PD (HR, 0.50; 95% CI, 0.30 - 0.82). In continuous analyses, a 1-month increase in the time to the first peritonitis episode was associated with a 2% decreased risk of technique failure (HR, 0.98; 95% CI, 0.97 - 0.99), a 3% decreased risk of patient mortality (HR, 0.97; 95% CI, 0.95 - 0.99), and a 2% decreased risk of dropout from PD (HR, 98%; 95% CI, 0.97 - 0.99). Peritonitis rate was inversely correlated with time to first peritonitis according to the Spearman analysis (r = -0.64, p < 0.001).

CONCLUSIONS

Time to first peritonitis is significantly correlated with clinical outcomes of peritonitis patients with early peritonitis patients having poor prognosis. Patients with shorter time to first peritonitis were prone to having a higher peritonitis rate.

Peritoneal dialysis associated infections: An update on diagnosis and management

Peritoneal dialysis (PD) is associated with a high risk of infection of the peritoneum, subcutaneous tunnel and catheter exit site. Although quality standards demand an infection rate < 0.67 episodes/patient/year on dialysis, the reported overall rate of PD associated infection is 0.24-1.66 episodes/patient/year. It is estimated that for every 0.5-per-year increase in peritonitis rate, the risk of death increases by 4% and 18% of the episodes resulted in removal of the PD catheter and 3.5% resulted in death. Improved diagnosis, increased awareness of causative agents in addition to other measures will facilitate prompt management of PD associated infection and salvage of PD modality. The aims of this review are to determine the magnitude of the infection problem, identify possible risk factors and provide an update on the diagnosis and management of PD associated infection. Gram-positive cocci such as Staphylococcus epidermidis, other coagulase negative staphylococcoci, and Staphylococcus aureus (S. aureus) are the most frequent aetiological agents of PD-associated peritonitis worldwide. Empiric antibiotic therapy must cover both gram-positive and gram-negative organisms. However, use of systemic vancomycin and ciprofloxacin administration for example, is a simple and efficient first-line protocol antibiotic therapy for PD peritonitis - success rate of 77%. However, for fungal PD peritonitis, it is now standard practice to remove PD catheters in addition to antifungal treatment for a minimum of 3 wk and subsequent transfer to hemodialysis. To prevent PD associated infections, prophylactic antibiotic administration before catheter placement, adequate patient training, exit-site care, and treatment for S. aureus nasal carriage should be employed. Mupirocin treatment can reduce the risk of exit site infection by 46% but it cannot decrease the risk of peritonitis due to all organisms.

Peritoneal Dialysis Drop-out: Causes and Prevention Strategies

Peritoneal dialysis (PD) as a renal replacement therapy (RRT) has become wide spread since its inception more than twenty-five years back. Since then, several advances have been made and PD has been accepted as an alternative therapy to hemodialysis (HD), with excellent survival, lower cost, and improved quality of life. In spite of comparable survival of HD and PD, improved PD techniques over the last few years, and lower health care costs with PD, PD prevalence remains low in many countries. An important reason for the low PD prevalence is patient dropouts, that is, transfer to HD. The reasons for dropouts are multifactorial, that is, modality related, system related, and patient related. These include episodes of peritonitis, catheter-related problems, ultrafiltration failure, patient fatigue, and provider comfort. This review discusses the various factors that contribute to PD dropout and the strategies to prevent it.

Encapsulating peritoneal sclerosis: what have we learned?

Encapsulating peritoneal sclerosis (EPS) is a rare complication of peritoneal dialysis (PD), but carries significant morbidity and mortality. We review the clinical features and radiologic and histologic changes found at diagnosis of EPS. Although EPS is strongly associated with the duration of PD, the pathogenesis remains only partly understood. We discuss the mechanisms thought to underlie the abnormally thickened, sclerotic peritoneal membrane seen in long-term PD patients including epithelial to mesenchymal transition and the molecular mediators of fibrosis and angiogenesis. We review how exposure to high-glucose, nonphysiological dialysis fluids, peritonitis, and uremia may be responsible for these changes. Much remains to be learned about optimal management of EPS, both medical and surgical, because the literature lacks controlled studies. Future research challenges include defining the role of surgery, immunosuppression, and antifibrotic agents in the management of EPS. We also need to understand why some patients progress from asymptomatic peritoneal sclerosis to the extreme levels of fibrin deposition and bowel encapsulation seen in EPS. Screening PD patients for potential future EPS remains difficult, and we need strategies for monitoring patients on longer-term PD that enable us to better quantify the risk of EPS for the individual patient.

Prevention of peritoneal dialysis-related infections

Despite substantial advances in peritoneal dialysis (PD) as a renal replacement modality, PD-related infection remains an important cause of morbidity, technique failure, and mortality. This review describes the microbiology and outcomes of PD peritonitis and catheter infection, followed by a discussion of several strategies that may reduce the risk of PD-related infections. Strategies that are reviewed include use of antibiotics at the time of PD catheter insertion, selection of PD catheter design and insertion technique, patient training, PD connectology, exit site prophylaxis, periprocedural prophylaxis, fungal prophylaxis, and choice of PD solutions.

Microbiology and outcomes of peritonitis in Australian peritoneal dialysis patients

We analyzed data from the Australia and New Zealand Dialysis and Transplant Registry for 1 October 2003 to 31 December 2008 with the aim of describing the nature of peritonitis, therapies, and outcomes in patients on peritoneal dialysis (PD) in Australia. At least 1 episode of PD was observed in 6639 patients. The overall peritonitis rate was 0.60 episodes per patient-year (95% confidence interval: 0.59 to 0.62 episodes), with 6229 peritonitis episodes occurring in 3136 patients. Of those episodes, 13% were culture-negative, and 11% were polymicrobial. Gram-positive organisms were isolated in 53.4% of single-organism peritonitis episodes, and gram-negative organisms, in 23.6%. Mycobacterial and fungal peritonitis episodes were rare. Initial antibiotic therapy for most peritonitis episodes used 2 agents (most commonly vancomycin and an aminoglycoside); in 77.2% of episodes, therapy was subsequently changed to a single agent. Tenckhoff catheter removal was required in 20.4% of cases at a median of 6 days, and catheter removal was more common in fungal, mycobacterial, and anaerobic infections, with a median time to removal of 4 - 5 days. Peritonitis was the cause of death in 2.6% of patients. Transfer to hemodialysis and hospitalization were frequent outcomes of peritonitis. There was no relationship between center size and peritonitis rate. The peritonitis rate in Australia between 2003 and 2008 was higher than that reported in many other countries, with a particularly higher rate of gram-negative peritonitis.

Low-GDP fluid (Gambrosol trio) attenuates decline of residual renal function in PD patients: a prospective randomized study

BACKGROUND

Residual renal function (RRF) impacts outcome of peritoneal dialysis (PD) patients. Some PD fluids contain glucose degradation products (GDPs) which have been shown to affect cell systems and tissues. They may also act as precursors of advanced glycosylation endproducts (AGEs) both locally and systemically, potentially inflicting damage to the kidney as the major organ for AGE elimination. We conducted a clinical study in PD patients to see if the content of GDP in the PD fluid has any influence on the decline of the residual renal function.

METHODS

In a multicentre approach, 80 patients (GFF > or = 3 mL/min/1.732 or creatinine clearance > or =3 mL/min/1.73 m(2)) were randomized to treatment with a PD fluid containing low levels of GDP or standard PD fluid for 18 months. RRF was assessed every 4-6 weeks. Fluid balance, mesothelial cell mass marker CA125, peritoneal membrane characteristics, C-reactive protein (CRP), total protein, albumin, electrolytes and phosphate were measured repeatedly.

RESULTS

Data from 69 patients revealed a significant difference in monthly RRF change: -1.5% (95% CI = -3.07% to +0.03%) with low GDP (43 patients) vs -4.3% (95% CI = -6.8% to -2.06%) with standard fluids (26 patients) (P = 0.0437), independent of angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker medication. Twenty-four-hour urine volume declined more slowly with low-GDP fluid compared to standard fluids (12 vs 38 mL/month, P = 0.0241), and monthly change of phosphate level was smaller (+0.013 vs +0.061 mg/dL, P = 0.0381).

CONCLUSIONS

Our prospective study demonstrates for the first time a significant benefit concerning preservation of RRF and urine volume of using a PD fluid with low GDP levels. These findings suggest that GDPs might affect patient outcome related to RRF.

Peritoneal membrane structural and functional changes during peritoneal dialysis

Peritoneal dialysis is now utilized as a renal replacement therapy modality in a substantial percentage of patients with end-stage renal disease, with excellent short-term patient and technique survival rates. However, the potential complications associated with longer-term therapy, such as ultrafiltration failure or encapsulating peritoneal sclerosis, have led to raise some concern about peritoneal dialysis as an adequate mode of treatment of end-stage renal disease in the long term. In the last decade, a substantial amount of information has been gathered on the characteristics of the peritoneal membrane at the onset of peritoneal dialysis, and on the anatomical and pathophysiologic changes that occur with long-term peritoneal dialysis. I will review this subject with a special focus on the various strategies that can help protect the peritoneal membrane during peritoneal dialysis so as to allow peritoneal dialysis to succeed as a long-term dialysis modality.