Comparison of double-bag and Y-set disconnect systems in continuous ambulatory peritoneal dialysis: a randomized prospective multicenter study

Association between the use of exchange devices for peritoneal dialysis fluids and peritonitis incidence: A nationwide cohort study

BACKGROUND

The use of exchange devices for peritoneal dialysis (PD) fluids is a common practice in Japan. Evidence on the effectiveness of exchange devices in preventing PD-related peritonitis is scarce. We evaluated the association between the use of exchange devices for PD fluids and peritonitis incidence.

METHODS

We retrospectively enrolled 3845 patients, aged ≥20 years, receiving PD for ≥3 months, with available data on the exchange procedure for PD fluids and peritonitis incidence that was obtained from the Japan Renal Data Registry, a nationwide annual survey. The patients were grouped according to whether the manual or device PD fluid exchange method was used. The onset of peritonitis was defined as a leukocyte count of >100/µL (neutrophils ≥50%) in PD effluents. We applied quasi-Poisson regression analyses to estimate the incidence rate ratio (IRR). Age, sex, PD vintage, body mass index, automated PD use, residual kidney function, comorbidities, haemoglobin and serum albumin were adjusted as potential confounders.

RESULTS

Older age, automated PD use, diabetes as comorbidity and lower haemoglobin levels were associated with the use of exchange devices for PD fluids. Patients using devices for PD fluid exchange (69.2%) had an increased risk of peritonitis of 37% (IRR: 1.37, 95% confidence interval (CI): 1.07-1.75) and 28% (IRR: 1.28, 95% CI: 1.00-1.63) in the crude and multivariate adjustment models, respectively.

CONCLUSIONS

The use of exchange devices for PD fluids and peritonitis incidence showed no favourable association. There may remain possible residual confounding by indication.

Gram-Negative Peritonitis—The Achilles Heel of Peritoneal Dialysis?

Peritonitis caused by gram-negative bacteria is a serious complication of peritoneal dialysis. Antibiotic resistance is common, and response to medical treatment is often poor. In the present article, we review recent advances in the understanding of the pathogenesis and treatment of this serious condition.

Adequacy Targets of Peritoneal Dialysis in the Asian Population

End-stage renal disease affects a large number of patients in Asia. The percentage of patients utilizing PD varies significantly in Asian countries. Continuous ambulatory peritoneal dialysis (CAPD) accounts for about 80% of the dialysis population in Hong Kong.

In this review, we address several questions related to adequacy targets in Asians: Are Asians different? Is dialysis adequacy important for Asians? What is the magnitude of the benefit and the optimal dose of dialysis prescription? Is the adequacy target realistic?

The current international recommendations, including the Dialysis Outcomes Quality Initiative guidelines, are compared with some of our own data for Asian patients. Our published data on dialysis adequacy, nutrition, residual renal function, and peritoneal membrane transport showed that those factors have a significant impact on the morbidity and mortality of PD patients in Hong Kong.

Our results show that solute clearance as measured by Kt/V has a significant impact on the outcome of Asian CAPD patients. Although Chinese PD patients have excellent medium-term patient and technique survival despite an apparently lower Kt/V as compared with the CANUSA standard, that favorable outcome should not prevent nephrologists from providing adequate dialysis to Asian patients. From our own data and analysis, we propose a target Kt/V of 1.9 in Asian CAPD populations. Small-volume dialysis (6 L daily) may be an acceptable compromise in some Asian populations with a smaller body size, especially with residual renal function, given the financial constraints in some developing countries.

Dialysis adequacy means more than a Kt/V value; other clinical parameters are equally if not more important. Thus we should also aim at achieving adequate fluid removal and volume homeostasis, blood pressure control, good nutrition, normal acid–base balance, normal mineral metabolism, minimal anemia, and normal lipid metabolism.

Polymicrobial Outbreak of Intermittent Peritoneal Dialysis Peritonitis during External Wall Renovation at a Dialysis Center

Objective

To investigate an outbreak of peritonitis in intermittent peritoneal dialysis (IPD) patients.

Design

An outbreak investigation was performed to identify the etiology of the polymicrobial outbreak, and a retrospective case-control study was conducted to assess the risk factors for development of peritonitis.

Setting

Renal dialysis center.

Patients

Ten episodes of peritonitis occurred in 8 of 61 patients over a 6-month period in which 669 IPD procedures were analyzed.

Interventions

Field visit to renal dialysis center to examine the entire IPD procedure, inspect the hospital environment, and perform air bacterial count.

Main Outcome Measures

The environmental factors and risk factors contributing to the polymicrobial peritonitis outbreak in IPD patients. The incidence of IPD peritonitis was determined before and after interventions.

Results

The causative organisms included Acinetobacter baumanii ( 6 ), Stenotrophomonas maltophilia ( 2 ), Pseudomonas aeruginosa ( 1 ), Candida albicans ( 1 ), C. tropicalis ( 1 ), Enterococcus ( 3 ), and Enterobacteriaceae ( 2 ). Four episodes of peritonitis involved infection by more than one organism. Air sampling of the environment detected a median of 110 colony forming units of bacteria per cubic meter of air, 10% of which were found to be Acinetobacter baumanii. The source of this polymicrobial outbreak was attributed to the bamboo scaffolding structure covering the external wall of the hospital during renovation. A retrospective case-control study indicated that the absence of the flush-before-fill step was a risk factor for development of peritonitis.

Conclusion

In addition to invasive aspergillosis in transplant or oncology patients, Acinetobacter peritonitis in dialysis patients should be considered another microbial cause of outbreak associated with hospital renovation.

Are Three Exchanges Suitable for Asian Patients on Peritoneal Dialysis?

Phenomenal growth in continuous ambulatory peritoneal dialysis (CAPD) has occurred in the developing countries of Asia. In many regions in Asia, neither governments nor insurance companies fully cover treatment expenses for dialysis. Hence, patients in developing countries such as India, Bangladesh, Pakistan, and Nepal use just three 2-L exchanges daily. Typical practice in many centers is to do daytime CAPD with a dry night. Most of our Indian patients who are on three exchanges per day showed a Kt/V of 1.67 and 2-year survival rate of 60% with a normalized protein equivalent of nitrogen appearance of 0.73 – 0.80 g/kg daily. Vegetarians had a lower protein consumption rate and lower serum albumin levels. Peritoneal membrane characteristics vary among high, high average, and low average in various regions of Asia. The prevalence of diabetic nephropathy, with its associated comorbid conditions, as a major cause of end-stage renal disease in the Indian subcontinent explains the differences in the CAPD mortality rates between India and various Asian countries. Given the financial constraints in countries in Asia, small-volume dialysis of 6 L daily may be an acceptable compromise in some patient populations with a smaller body size and significant residual renal function; however, dialysis dose should be individualized according to the needs of each patient.

The Cost Barrier to Peritoneal Dialysis in the Developing World—An Asian Perspective

Countries in Asia vary significantly in culture and socioeconomic status. Dialysis costs and reimbursement structures are significant factors in decisions about the rates and modalities of renal replacement therapy. From our survey of Asian nephrologists conducted in 2001, a number of observations can be made.

In many developing countries, the annual cost of continuous ambulatory peritoneal dialysis (CAPD) is greater than the per-capita gross national income (GNI). The median cost of a 2-L bag of peritoneal dialysis (PD) fluid is around US$5. The absolute cost of PD fluid among countries with significant differences in per-capita GNI actually varies very little. Thus, most renal failure patients can be expected to have problems accessing PD therapy in developing countries in Asia.

In countries with unequal reimbursement policies for PD versus hemodialysis, a lack of incentive to prescribe PD also exists. Automated PD is nearly non existent in many developing countries in Asia.

Some possible ways to reduce the cost barriers to PD in those countries include

• individual governments providing more public funding for treating dialysis patients;

• dialysate-producing companies reducing the cost of their products;

• physicians using appropriately smaller exchange volumes (3 x 2 L) in some Asian patients with smaller body sizes and with residual renal function; and

• reducing the complication rate for PD (for example, peritonitis) thereby reducing the costs required for treatment and hospitalization.

Setting up a Continuous Ambulatory Peritoneal Dialysis Training Program

Continuous ambulatory peritoneal dialysis (CAPD) training programs have become fundamental patient education programs in renal centers providing peritoneal dialysis (PD) services. Several key topics must be addressed in setting up a CAPD training program:

• Health care and organizational issues • Multidisciplinary team approach • Evidence-based practice • Pre-training patient assessment • Patient training • Program evaluation

The PD nurses should identify key learning objectives for patient training. The essential elements of CAPD training are the training content and schedule, training assessment, and teaching methods. Program set-up also includes establishing a back-up system and follow-up protocols, which are essential for continuity of care in renal patients. Outcomes such as rates of peritonitis and exit-site infection, unplanned readmission, and patient satisfaction are all important indicators when the results of CAPD training programs are reviewed. The development and successful implementation of a cost-effective CAPD training program has a significant impact on patient outcomes in the renal specialty.

How to Have a Successful Peritoneal Dialysis Program

The proportion of end-stage renal disease patients on continuous ambulatory peritoneal dialysis (CAPD) has increased by twofold in Hong Kong over last two decades, accounting for 80% of the entire dialysis population. Our encouraging outcome results—a 2-year actuarial patient survival of 83%, and a 2-year technique survival of 72.8%—further testify to the success of CAPD in our territory. A relatively constant successful outcome has been achieved despite an increasing prevalence of diabetes mellitus and an aging population. The present review postulates the reasons behind our success. Apart from reimbursement policy, technique-related factors, and center effects, inherent patient factors—including baseline survival advantage of Chinese patients, genetic difference, cardiovascular risk factors, and possibly lower dialysis volume requirement and compliance—are thought to be contributory. As for the future, more efforts are needed to further improve the technique survival rate and the nutritional status, psychosocial well-being, and rehabilitation of CAPD patients. Judicious assessment of peritoneal dialysis adequacy and preservation of residual renal function should be constantly exercised to tailor treatment to the needs of Chinese CAPD patients.

A Quarter of a Century of Adult Peritoneal Dialysis-Related Peritonitis at an Australian Medical Center

Background

Peritonitis remains one of the major complications of peritoneal dialysis (PD) and results in reduced technique survival and increased patient morbidity and mortality.

Methods

We prospectively recorded comprehensive data on all episodes of PD peritonitis over a 25-year period, including organisms isolated and antibiotic sensitivities. Data on 1588 PD patient-years with 2073 episodes of peritonitis were analyzed; 2089 organisms were isolated in 608 patients. Peritoneal dialysis technique and patient survival were also recorded.

Results

There was a significant decline over the years in the incidence of peritonitis, from 6.5 to 0.35 episodes/patient-year, with the decline in the post twin-bag era from 2.3 to 0.47 ( p < 0.001) due primarily to a decrease in gram-positive organisms. The most common isolates (68.9%) were gram-positive organisms; gram-negative organisms comprised 26.8% and fungi 4.1%. Coagulase-negative staphylococci were the most common pathogen isolated (35.3%). Culture-negative peritonitis was seen in 13.4% of episodes.

Conclusion

This is the largest series of PD peritonitis reported, demonstrating a dramatic reduction over a 25-year period and also detailing the changing trends of organisms isolated in association with improved technique and patient survival. Although rates have improved, peritonitis remains a major complication and further research needs to be done to improve both PD technique and patient survival.

A Randomized Controlled Trial Comparing Mupirocin versus Polysporin Triple for the Prevention of Catheter-Related Infections in Peritoneal Dialysis Patients (The MP3 Study)

Background

Peritonitis remains the most serious complication of peritoneal dialysis (PD). Gram-positive organisms are among the most common causes of PD peritonitis; however, recent trends show increasing rates of gram-negative and fungal infections. Strategies to prevent peritonitis include the use of prophylactic topical mupirocin at the site where the PD catheter exits from the abdominal wall; however, mupirocin does not afford protection against gram-negative or fungal infections. The aim of this study is to determine if the incidence of catheter-related infections (exit-site infection, tunnel infection, or peritonitis) is significantly reduced by the routine application of Polysporin Triple antibiotic ointment (Pfizer Canada, Markham, Ontario, Canada) in comparison to mupirocin ointment.

Methods and Design

The Mupirocin Versus Polysporin Triple Study (MP3) is a multicenter, randomized, double-blinded controlled study comparing Polysporin Triple (P3) against the current standard of care. The aim of the study is to recruit 200 patients being treated with or starting on PD and randomize them to receive either mupirocin or P3 at the catheter exit site. Patients will be followed for 18 months or until death or transfer from PD to an alternate treatment modality. The primary outcome will be the time to first catheter-related infection. Catheter-related infections will be strictly defined using current guidelines and categorized into exit-site infections, infective peritonitis, or tunnel infections. The primary analysis will be an intention-to-treat analysis.

Discussion

The results of this study will help determine if the use of P3 is superior to mupirocin ointment in the prevention of catheter-related infections and will help guide evidence-based best practices.

Cefazolin plus Ceftazidime versus Imipenem / Cilastatin Monotherapy for Treatment of Capd Peritonitis — a Randomized Controlled Trial

Background

Peritonitis is a serious complication of peritoneal dialysis (PD). We studied the efficacy of imipenem / cilastatin monotherapy in the treatment of PD-related peritonitis.

Methods

We performed an open-label, randomized control study comparing imipenem / cilastatin monotherapy (treatment group) versus cefazolin plus ceftazidime (control group) in the treatment of PD peritonitis. The result was further compared to a historic group treated with cefazolin plus netilmycin. Outcome measures were primary response rate at day 10 and complete cure rate.

Results

We enrolled 51 patients in the treatment group, 51 in the control group, and identified 96 in the historic group. The primary response rate to the assigned antibiotics was 49.0%, 51.0%, and 49.0% for the treatment, control, and historic groups, respectively ( p = 0.97). The primary response rate allowing for change in antibiotic was 82.4%, 90.2%, and 82.3%, respectively, for the three groups ( p = 0.41). The complete cure rate was 72.5%, 80.4%, and 82.3%, respectively ( p = 0.60). Tenckhoff catheter removal was needed in 6 cases in the treatment group, 6 cases in the control group, and 13 cases in the historic group ( p = 0.90).

Conclusions

We concluded that monotherapy of imipenem / cilastatin has similar efficacy compared to the two standard regimens of cefazolin plus ceftazidime or netilmycin in the treatment of PD peritonitis.

Double bag or Y-set versus standard transfer systems for continuous ambulatory peritoneal dialysis in end-stage kidney disease

BACKGROUND

Peritonitis is the most frequent serious complication of continuous ambulatory peritoneal dialysis (CAPD). It has a major influence on the number of patients switching from CAPD to haemodialysis and has probably restricted the wider acceptance and uptake of CAPD as an alternative mode of dialysis.This is an update of a review first published in 2000.

OBJECTIVES

This systematic review sought to determine if modifications of the transfer set (Y-set or double bag systems) used in CAPD exchanges are associated with a reduction in peritonitis and an improvement in other relevant outcomes.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register through contact with the Trials Search Co-ordinator. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE and EMBASE. Date of last search: 22 October 2013.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing double bag, Y-set and standard peritoneal dialysis (PD) exchange systems in patients with end-stage kidney disease.

DATA COLLECTION AND ANALYSIS

Data were abstracted by a single investigator onto a standard form and analysed by Review Manager. Analysis was by a random effects model and results were expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

Twelve eligible trials with a total of 991 randomised patients were identified. Despite the large total number of patients, few trials covered the same interventions, small numbers of patients were enrolled in each trial and the methodological quality was suboptimal. Y-set and twin-bag systems were superior to conventional spike systems (7 trials, 485 patients, RR 0.64, 95% CI 0.53 to 0.77) in preventing peritonitis in PD.

AUTHORS' CONCLUSIONS

Disconnect systems should be the preferred exchange systems in CAPD.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for preserving residual kidney function in peritoneal dialysis patients

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) are widely used in peritoneal dialysis (PD) patients, yet controversy exists about their impact on residual kidney function.

OBJECTIVES

This review aimed to evaluate the benefits and harms of ACEis and ARBs for preserving residual kidney function in PD patients.

SEARCH METHODS

The Cochrane Renal Group's specialised register, Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE (OvidSP interface), Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI) and other resources were searched by applying a prespecified comprehensive search strategy. Date of last search: 01 May 2014.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing ACEis or ARBs with placebo, other antihypertensive drugs or each other in PD patients were included.

DATA COLLECTION AND ANALYSIS

Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors were contacted when published data were incomplete. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI). Heterogeneity among studies was explored using the Cochran Q statistic and the I² test, subgroup analyses and random effects meta-regression.

MAIN RESULTS

Six open-label studies (257 patients) were identified. One study compared ACEi with other antihypertensive drugs, three compared ARBs with other antihypertensive drugs, and two studies compared an ARB with an ACEi. Long-term use (≥ 12 months) of an ARB showed significantly benefit of preserving residual kidney function in continuous ambulatory PD (CAPD) patients (MD 1.11 mL/min/1.73 m², 95% CI 0.38 to 1.83), although there was no significant benefit when an ARB were used short-term (≤ six months). One study showed that compared with other antihypertensive drugs, long-term use (12 months) of the ACEi ramipril showed a significant reduction in the decline of residual kidney function in patients on CAPD (MD -0.93 mL/min/1.73m², 95% CI -0.75 to -0.11), and delayed the progression to complete anuria (RR 0.64, 95% CI 0.41 to 0.99). There was no significant difference in serum potassium, urinary protein excretion, Kt/V, weekly creatinine clearance and blood pressure for ARBs versus other antihypertensive drugs. Compared with other antihypertensive drugs, ramipril showed no difference in mortality and cardiovascular events. Compared with an ACEi, ARBs did not show any difference in residual kidney function.The selection bias assessment was low in four studies and unclear in two. Five studies were open-label; however the primary outcome (residual kidney function) was obtained objectively from laboratory tests, and were not likely to be influenced by the lack of blinding. Reporting bias was unclear in all six studies.

AUTHORS' CONCLUSIONS

Compared with other antihypertensive drugs, long-term use (≥ 12 months) of ACEis or ARBs showed additional benefits of preserving residual kidney function in CAPD patients. There was no significant difference on residual kidney function preservation between ARBs and ACEis. However, limited by the small number of RCTs enrolling small number of participants, there is currently insufficient evidence to support the use of an ACEi or an ARB as first line antihypertensive therapy in PD patients.

Clinical causes of inflammation in peritoneal dialysis patients

Inflammation at both systemic and local intraperitoneal levels commonly affects peritoneal dialysis (PD) patients. Interest in inflammatory markers as targets of therapeutic intervention has been considerable as they are recognised as predictors of poor clinical outcomes. However, prior to embarking on strategies to reduce inflammatory burden, it is of paramount importance to define the underlying processes that drive the chronic active inflammatory status. The present review aims to comprehensively describe clinical causes of inflammation in PD patients to which potential future strategies may be targeted.

Peritoneal dialysis-related peritonitis: towards improving evidence, practices, and outcomes

Peritonitis is a common serious complication of peritoneal dialysis that results in considerable morbidity, mortality, and health care costs. It also significantly limits the use of this important dialysis modality. Despite its importance as a patient safety issue, peritonitis practices and outcomes vary markedly and unacceptably among different centers, regions, and countries. This article reviews peritonitis risk factors, diagnosis, treatment, and prevention, particularly focusing on potential drivers of variable practices and outcomes, controversial or unresolved areas, and promising avenues warranting further research. Potential strategies for augmenting the existing limited evidence base and reducing the gap between evidence-based best practice and actual practice also are discussed.

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.

Predictors of peritonitis in patients on peritoneal dialysis: results of a large, prospective Canadian database

BACKGROUND AND OBJECTIVES

Despite the decreasing incidence of peritonitis among peritoneal dialysis (PD) patients over time, its occurrence is still associated with significant morbidity and mortality. Determining factors that are associated with PD peritonitis may facilitate the identification of patients who are at risk.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using data collected in the multicenter Baxter POET database between 1996 and 2005, the study population included incident Canadian PD patients. Potential predictors of peritonitis were sought using a negative binomial model and an Andersen-Gill model. Study variables included age, gender, race, cause of renal disease, diabetes status, transfer from hemodialysis (HD), previous renal transplant, and continuous ambulatory PD (CAPD) versus automated PD (APD).

RESULTS

Data were available for 4247 incident PD patients, including 1605 patients with a total of 2555 peritonitis episodes. Using the negative binomial regression model, factors that were independently associated with a higher peritonitis rate included age, Black race, and having transferred from HD. There was an interaction between gender and diabetes, with an increased risk for peritonitis among female patients with diabetes. The use of CAPD versus APD did not affect the peritonitis rate. The Andersen-Gill model for recurrent events yielded similar results.

CONCLUSIONS

Predictors of PD peritonitis included Black race, transferring from HD to PD, and diabetes among women. In contrast to previous findings, CAPD and APD were similar with regard to peritonitis risk.

Impact of age on peritonitis risk in peritoneal dialysis patients: an era effect

BACKGROUND AND OBJECTIVES

Despite reductions in the frequency of peritoneal dialysis (PD)-related infectious complications over time, peritonitis and catheter infection remain important causes of morbidity and mortality. Given the increasing number of elderly patients reaching end-stage renal disease, making informed decisions about PD utilization is contingent on an understanding of the infectious complications of PD in this population. We therefore studied the impact of age on infection rates, organisms and outcomes.

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

On the basis of data collected from 1996 to 2005 in the multicenter Baxter Peritonitis Organism Exit sites Tunnel infections database, the study population included 4247 incident Canadian PD patients: 1265 patients aged > or =70 yr and 2982 patients aged <70 yr. We defined two eras of PD initiation: 1996 to 2000 and 2001 to 2005.

RESULTS

In a negative binomial model, older age was independently associated with a higher peritonitis rate (rate ratio [RR] 1.06 per decade increase; 95% CI 1.01 to 1.10; P = 0.008). However, this association was present only among those who initiated PD at an earlier time (RR 1.13 per decade increase; 95% CI 1.07 to 1.20; P < 0.001 in 1996 to 2000 versus 1.01 per decade increase; 95% CI 0.95 to 1.06; P = 0.81 in 2001 to 2005). Catheter-related infections were less frequent with increasing age regardless of era (RR 0.93 per decade increase; 95% CI 0.89 to 0.97).

CONCLUSIONS

The higher peritonitis rate observed in elderly patients may represent an era effect, as age was not associated with peritonitis among patients initiating PD between 2001 and 2005. In addition, catheter infection was less frequent with increasing age.

Coagulase negative staphylococcal peritonitis in peritoneal dialysis patients: review of 232 consecutive cases

BACKGROUND AND OBJECTIVES

Coagulase-negative Staphylococcus species is the most common cause of peritoneal dialysis-related peritonitis; however, the optimal treatment strategy of coagulase-negative Staphylococcus species peritonitis remains controversial.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

All of the coagulase-negative Staphylococcus species peritonitis in a dialysis unit from 1995 to 2006 were reviewed. During this period, there were 2037 episodes of peritonitis recorded; 232 episodes (11.4%) in 155 patients were caused by coagulase-negative Staphylococcus species.

RESULTS

The overall primary response rate was 95.3%; the complete cure rate was 71.1%. Patients with a history of recent hospitalization or recent antibiotic therapy had a higher risk for developing methicillin-resistant strains. Episodes that were treated initially with cefazolin or vancomycin had similar primary response rate and complete cure rate. There were 33 (14.2%) episodes of relapse and 29 (12.5%) episodes of repeat peritonitis; 12 (60.6%) of the repeat episodes developed within 3 mo after completion of antibiotics. Relapse or repeat episodes had a significantly lower complete cure rate than the other episodes. For relapse or repeat episodes, treatment with effective antibiotics for 3 wk was associated with a significantly higher complete cure rate than the conventional 2-wk treatment.

CONCLUSIONS

Coagulase-negative Staphylococcus species peritonitis remains a common complication of peritoneal dialysis. Methicillin resistance is common, but the treatment outcome remains favorable when cefazolin is used as the first-line antibiotic. A 3-wk course of antibiotic can probably achieve a higher cure rate in relapse or repeat episodes.

A Randomized, Multicenter, Open-Label Trial to Determine Peritonitis Rate, Product Defect, and Technique Survival Between ANDY-Disc® and UltraBag® in Patients on CAPD

BACKGROUND

With the various twin-bag systems available on the market, we decided to conduct a therapeutic equivalence study comparing ANDY-Disc (Fresenius Medical Care, Bad Homburg, Germany) with UltraBag (Baxter, Deerfield, IL) in patients on continuous ambulatory peritoneal dialysis (CAPD) therapy.

METHODS

This multicenter, open-label, parallel-group, randomized trial is designed to show the therapeutic equivalence of ANDY-Disc with UltraBag. All CAPD patients from the 6 participating centers who met inclusion/exclusion criteria were enrolled into the trial. They were randomly assigned and converted from the Y-disconnect system (Ultraset; Baxter) to the twin-bag systems. The primary outcome variable is peritonitis, and secondary outcome parameters are technique failure or product defect.

RESULTS

From April 2002 to May 2003, a total of 270 patients were recruited for this study. Overall peritonitis rates were 22.9 patient-months/episode for ANDY-Disc and 35.0 patient-months/episode for UltraBag. The overall peritonitis rate for ANDY-Disc was 53% greater compared with UltraBag, but the 95% confidence interval overlaps the prespecified margin of equivalence. There were more product defects reported with ANDY-Disc; 236 product defects compared with 17 with UltraBag. The time series of the number of product defects and peritonitis count on the ANDY-Disc arm suggests a possible cause-and-effect relationship.

CONCLUSION

Therapeutic equivalence of ANDY-Disc to UltraBag could not be established with respect to peritonitis. There is a trend toward greater risk for peritonitis on the Andy-Disc arm. There also is a suggestive cause-and-effect relation between the occurrence of product defect and peritonitis on the ANDY-Disc arm during the early part of the trial.

Antimicrobial agents and catheter-related interventions to prevent peritonitis in peritoneal dialysis: Using evidence in the context of clinical practice

BACKGROUND

Peritonitis still represents a common and major complication of peritoneal dialysis. The broader adoption of several strategies, including antimicrobial and catheter related interventions, has been advocated to prevent or reduce the risk of peritonitis in peritoneal dialysis.

METHODS

In this article we start with the presentation of a clinical case where concern exists about the strategies for preventing peritoneal dialysis peritonitis. We then look at the available evidence in the form of systematic reviews of randomized trials and individual randomized trials of interventions to prevent peritonitis in peritoneal dialysis. A summary of the evidence is provided and then put in context with the clinical case scenario.

RESULTS

Nineteen eligible trials (1949 patients) of antimicrobial agents and 37 (2822 patients) of catheter related interventions to prevent peritonitis in peritoneal dialysis were identified. Nasal mupirocin compared with placebo significantly reduced the exit-site and tunnel infection rate (1 trial, 2716 patient months, RR 0.58, 95% CI 0.40 to 0.85) but not peritonitis rate (1 trial, 2716 patient months, RR 0.84, 95% CI 0.44 to 1.60). As for antimicrobial strategies, perioperative intravenous antibiotics compared with no treatment significantly reduced the risk of early peritonitis (4 trials, 335 patients, RR 0.35, 95% CI 0.15 to 0.80) but not exit site and tunnel infection (3 trials, 114 patients, RR 0.32, 95% CI 0.02 to 4.81). As for catheter related strategies, Y-set and twin-bag systems were superior to conventional spike systems (7 trials, 485 patients, RR 0.64, 95% CI 0.53 to 0.77) and no other catheter-related intervention was demonstrated to prevent peritonitis in PD.

CONCLUSIONS

Evidence exists to support the use of perioperative intravenous antibiotic prophylaxis at the time of catheter placement, the twin-bag and Y-set system, as well as prophylaxis with mupirocin in Staphylococcus aureus nasal carriers. Despite lack of evidence, several other agents are used and recommended in major international guidelines, which is reasonable but requires further investigation.

Enterobacteriaceae peritonitis complicating peritoneal dialysis: A review of 210 consecutive cases

Enterobacteriaceae peritonitis is a serious complication in peritoneal dialysis (PD), but the clinical course of PD-related Enterobacteriaceae peritonitis remains unclear. We reviewed all Enterobacteriaceae peritonitis in our dialysis unit from 1995 to 2004. During this period, there were 1748 episodes of peritonitis recorded; 210 episodes (12.0%) in 123 patients were caused by Enterobacteriaceae. The most common species was Escherichia coli, accounting for 111 episodes. The primary response rate was 84.8% and complete cure rate was 58.1%. The presence of exit site infection was associated with a lower complete cure rate (43.2 versus 61.3%, P = 0.034). A total of 82 episodes (39.0%) did not respond to single antibiotic treatment despite sensitivity in vitro, and a second antibiotic was added. Patients treated with two antibiotics had a marginally lower risk of relapse and recurrence than those with one antibiotic (21.4 versus 36.1%, P = 0.051). The episodes that had recent antibiotic therapy had a marginally lower complete cure rate (49.3 versus 62.8%, P = 0.06). There was a gradual increase in the prevalence of resistance to several commonly used antibiotics over the years. Recent antibiotic therapy was associated with resistance to cefotaxime, ceftazidime, cefoperazone/sulbactam, and piperacillin/tazobactam. We conclude that Enterobacteriaceae peritonitis is a serious complication of PD. Recent antibiotic therapy is the major risk factor of antibiotic resistance. Exit site infection, and probably recent antibiotic therapy, is associated with poor therapeutic response. Contrary to the current recommendation, treatment with two antibiotics may reduce the risk of relapse and recurrence.

Change in bacterial aetiology of peritoneal dialysis-related peritonitis over 10 years: experience from a centre in South-East Asia

This study reviewed 1787 episodes of peritoneal dialysis (PD)-related peritonitis in 544 patients between 1994 and 2003. The overall rate of peritonitis was 0.68 episodes/year of PD, but decreased from 1.10 to 0.46 episodes/year between 1994 and 2003. The incidence of peritonitis caused by coagulase-negative staphylococci declined between 1994 and 1998 from 0.21 to 0.06 episodes/year of PD, coinciding with a reduction in the use of spike PD sets. There was a 60.1% response rate to antibiotics throughout the period, but the percentage of cases that required modification of the initial empirical antibiotic regimen rose from 13.6% to 58.7%, indicating that treatment should be individualised.

Is there a survival advantage in Asian peritoneal dialysis patients?

Over the last decade, epidemiological surveys and qualitative research literature have demonstrated and validated a better survival in the Asian peritoneal dialysis population. This review summarizes the current understanding of Asian peritoneal dialysis patient survival and attempts to scrutinize the supposed survival advantage of this population group. We outlined the published peritoneal dialysis survival data from a literature search, with reference to dialysis patient cohorts from 1983 through 2002 for prevalent cases and 1980 through 2002 for incident patients. Two-year and 5-year patient survival rates in excess of 80% and 60% respectively were demonstrated in Asian countries, which compared favorably with the CANUSA, ADEMEX and most Caucasian series. Better end-stage renal disease patient survival is apparent despite a dialysis adequacy disadvantage, for reasons yet to be identified. As is the case of other racial disparities in medical care, such a difference is a product of more than biological differences and include budgetary barrier, health care system and geographic variation, physician bias and statistical pitfalls. Particular efforts should therefore be made to explore the underlying reason(s) for the Asian peritoneal dialysis patient survival advantage. Alternative approach and guidelines to peritoneal dialysis delivery in Asia might be warranted.

Comparison of clinical outcome and ease of handling in two double-bag systems in continuous ambulatory peritoneal dialysis: a prospective, randomized, controlled, multicenter study

BACKGROUND

We performed a prospective, randomized, controlled, multicenter study on the use of two double-bag disconnect systems: Stay-Safe (SS; Fresenius Deutschland GmbH2) and Ultrabag (UB; Baxter Healthcare, Deerfield, IL) to assess the ease of handling, peritonitis rate, exit-site infection rate, and clinical outcome.

METHODS

We enrolled 110 new continuous ambulatory peritoneal dialysis (CAPD) patients; 55 patients were randomized to SS treatment, and 55 patients, to UB treatment.

RESULTS

Patients using the UB and SS systems were followed up for 946 and 846 patient-months, respectively. There were 21 episodes of peritonitis in 18 patients in the UB group and 23 episodes in 18 patients in the SS group. No significant difference was observed in peritonitis rates between the two systems, which were 45 and 36.8 patient-months per episode for the UB and SS groups, respectively. At 12 months, 82.1% of patients in the UB group and 72.1% in the SS group were free of peritonitis; at 18 months, 71.1% and 62.2% were free of peritonitis for the UB and SS groups, respectively (P = 0.559). Gram-positive organisms accounted for 28.6% of infections in the UB group and 39.1% in the SS group. Exit-site infection rates were one episode per 21 patient-months versus 19.2 patient-months in the UB and SS groups, respectively (P = 0.743). Patients perceived SS as easier to handle in 4 of the 13 steps immediately post-CAPD training. However, there was no significant difference in rankings between the two systems after 1 month of adaptation. Median training periods were 4 and 5 days for the SS and UB groups, respectively (P = 0.640).

CONCLUSION

The two double-bag systems (UB and SS) have similar incidences of peritonitis and exit-site infection. Both systems showed comparably good clinical outcome. The SS system is easier to learn during the initial training period, but the difference is not significant after 1 month's adaptation.

Clinical course of peritonitis due to Pseudomonas species complicating peritoneal dialysis: a review of 104 cases

BACKGROUND

Peritonitis due to Pseudomonas species is a serious complication in continuous ambulatory peritoneal dialysis (CAPD) patients. The clinical course of peritonitis due to Pseudomonas complicating CAPD remains unclear.

METHODS

All of the Pseudomonas species episodes of peritonitis in our dialysis unit were studied from 1995 to 1999. During this period, there were 859 episodes of peritonitis recorded, 113 of which were caused by the Pseudomonas species. Nine episodes were excluded because they were mixed growth. The remaining 104 episodes in 68 patients were reviewed.

RESULTS

The underlying renal diagnosis and prevalence of comorbid conditions of the 68 patients were similar to those found in our entire dialysis population. There was a history of antibiotic therapy within 30 days of the onset of peritonitis due to the Pseudomonas species in 69 episodes (66.3%). In 47 episodes (45.2%) there was a concomitant exit site infection. The overall primary response rate was 60.6% and the complete cure rate was 22.1%. The presence of exit site infection was associated with a lower primary response rate (22 in 47 vs. 41 in 57 episodes, P < 0.01) and a lower complete cure rate (5 in 47 vs. 18 in 57 episodes, P < 0.02). The episodes that had received recent antibiotic therapy had a significantly lower complete cure rate than the de novo cases (8 in 69 vs. 15 in 35 episodes, P < 0.001). Episodes receiving third-generation cephalosporin as part of the initial antibiotic regimen had a significantly higher primary response rate than the ones that initially received aminoglycoside (54 in 81 episodes vs. 8 in 22 episodes, P < 0.05), but their complete cure rates were similar. Twenty-four cases failed to respond to antibiotics and the Tenckhoff catheter was removed. The chance of returning to CAPD was higher when the Tenckhoff catheter was removed on day 10 than on day 15 (9 in 14 cases vs. 5 in 10 cases), although the result was not statistically significant. The Tenckhoff catheter was removed and replaced at another site simultaneously in another 14 cases after the effluent cleared up. None of these patients had a relapse of peritonitis within three months.

CONCLUSIONS

Recent antibiotic therapy is the major risk factor for peritonitis due to the Pseudomonas species. Exit site infection and recent antibiotic therapy are associated with poor therapeutic response to antibiotics. When the therapeutic response is suboptimal, early Tenckhoff catheter removal may help preserve the peritoneum for further peritoneal dialysis. Elective Tenckhoff catheter exchange after clearing up the peritoneal dialysis effluent may also reduce the likelihood of relapse. It is desirable to use third-generation cephalosporin in the initial antibiotic regimen for peritonitis treatment in localities with a high incidence of peritonitis due to the Pseudomonas species.

Do the Y-set and double-bag systems reduce the incidence of CAPD peritonitis? A systematic review of randomized controlled trials

BACKGROUND

Peritonitis is the most frequent serious complication of continuous ambulatory peritoneal dialysis (CAPD). It has a major influence on the number of patients switching from CAPD to haemodialysis and has probably restricted the wider acceptance and uptake of CAPD as an alternative mode of dialysis. This systematic review sought to determine if modifications of the transfer set (Y-set or double-bag systems) used in CAPD exchanges are associated with a reduction in peritonitis and an improvement in other relevant outcomes.

METHODS

Based on a comprehensive search strategy, we undertook a systematic review of randomized or quasi-randomized controlled trials comparing double-bag and/or Y-set CAPD exchange systems with standard systems, or comparing double-bag with Y-set systems, in patients with end-stage renal disease (ESRD) treated with CAPD. Only published data were used. Data were abstracted by a single investigator onto a standard form and subsequently entered into Review Manager 4.0.4. Its statistical package, Metaview 3.1, calculated an odds ratio (OR) for dichotomous data and a (weighted) mean difference for continuous data with 95% confidence intervals.

RESULTS

Twelve eligible trials with a total of 991 randomized patients were identified. In trials comparing either the Y-set or double-bag systems with the standard systems, significantly fewer patients (133/363 vs 158/263; OR 0.33, 95% CI 0.24-0.46) experienced peritonitis and the number of patient-months on CAPD per episode of peritonitis was consistently greater. When the double-bag systems were compared with the Y-set systems significantly fewer patients experienced peritonitis (44/154 vs 66/138; OR 0.44, 95% CI 0.27-0.71) and the number of patient-months on CAPD per episode of peritonitis was also greater.

CONCLUSIONS

Double-bag systems should be the preferred exchange systems in CAPD.

Staphylococcal peritonitis in continuous ambulatory peritoneal dialysis: colonization with identical strains at exit site, nose, and hands

To evaluate the relationship of nasal or skin Staphylococcus carrier status with identical strains and the development of staphylococcal peritonitis, 59 consecutive peritonitis episodes in patients using a twin-bag system for continuous ambulatory peritoneal dialysis from a single dialysis center were prospectively studied. Dialysate samples and exit-site, nose, and nail swabs from patients and their dialysis partners were obtained on the same day for culture. When bacteria belonging to the same species of the Staphylococcus genus were isolated from dialysate and at least one extraperitoneal anatomic site, pulsed-field gel electrophoresis typing was performed. The bacterial strains isolated from catheter exit site, nose, or nails of each patient and his or her dialysis partner were classified as identical or different. Twenty-seven of the 59 peritonitis episodes (46%) were caused by staphylococci. Nineteen of these 27 patients carried the same Staphylococcus species causing the peritonitis episode at the exit site, nose, or nails, but only 17 patients (63%) carried an identical strain. Four of 5 dialysis partners carried the same Staphylococcus species causing the peritonitis episode at nose or nails, but the strain was identical for only 3 dialysis partners (60%). Four patients and 1 dialysis partner carried unrelated strains of the Staphylococcus species causing the peritonitis episode. The most frequently colonized site with strains identical to that causing the peritonitis episode was the catheter exit site, followed by nose and nails. This finding may be clinically relevant because eradication of Staphylococcus aureus colonizing the catheter exit site may be more important and have a greater likelihood of success than maneuvers directed to more distant locations.

Double bag or Y-set versus standard transfer systems for continuous ambulatory peritoneal dialysis in end-stage renal disease

BACKGROUND

Peritonitis is the most frequent serious complication of continuous ambulatory peritoneal dialysis (CAPD). It has a major influence on the number of patients switching from CAPD to haemodialysis and has probably restricted the wider acceptance and uptake of CAPD as an alternative mode of dialysis.

OBJECTIVES

This systematic review sought to determine if modifications of the transfer set (Y-set or double bag systems) used in CAPD exchanges are associated with a reduction in peritonitis and an improvement in other relevant outcomes.

SEARCH STRATEGY

A broad search strategy was employed which attempted to identify all RCTs or quasi-RCTs relevant to the management of end-stage renal disease (ESRD). Five electronic databases were searched (Medline 1966-1999, EMBASE 1984-1999, CINAHL 1982-1996, BIOSIS 1985-1996 and the Cochrane Library), authors of included studies and relevant biomedical companies were contacted, reference lists of identified RCTs and relevant narrative reviews were screened and Kidney International 1980-1997 was hand searched.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing double bag, Y-set and standard CAPD exchange systems in patients with ESRD.

DATA COLLECTION AND ANALYSIS

Data were abstracted by a single investigator onto a standard form and subsequently entered into Review Manager 4.0.4. Odds Ratio (OR) for dichotomous data and a (Weighted) Mean Difference (WMD) for continuous data were calculated with 95% confidence intervals (95% CI).

MAIN RESULTS

Twelve eligible trials with a total of 991 randomised patients were identified. In trials comparing either the Y-set or double bag systems with the standard systems significantly fewer patients (OR 0.33, 95% CI 0.24 to 0.46) experienced peritonitis and the number of patient-months on CAPD per episode of peritonitis were consistently greater. When the double bag systems were compared with the Y-set systems significantly fewer patients experienced peritonitis (OR 0.44, 95% CI 0.27 to 0.71) and the numbers of patient-months on CAPD/ episode of peritonitis were also greater.

REVIEWER'S CONCLUSIONS

Double bag systems should be the preferred exchange systems in CAPD.