Continuous ambulatory peritoneal dialysis peritonitis: Microbiology and outcomes

Context

Continuous ambulatory peritoneal dialysis (CAPD) is now a preferred mode of the treatment in patients with end-stage renal disease, but peritonitis remains to be a shortcoming of CAPD. High-culture negativity, emerging drug resistance and peritoneal dialysis (PD)-related morbidity and mortality have been a challenge to tackle.

Aims

The present study was taken up to compare the the various culture methods and to identify the spectrum of organisms causing CAPD peritonitis and their outcome.

Settings and Design

A prospective, observational, cross-sectional study was conducted at a tertiary care teaching hospital in Hyderabad over a period of 1 year.

Subjects and Methods

Dialysate fluid from 100 episodes of clinically suspected peritonitis in 75 patients was processed by conventional centrifuging, water lysis, direct inoculation and addition of centrifuged pellet into brain-heart infusion broth and by automated blood culture system. Identification and antibiotic susceptibility of organisms was done, and the outcome of PD-related peritonitis was analysed.

Statistical Analysis Used

The categorical data and continuous data were analysed using the Chi-square test and Student's t-test, respectively. P < 0.05 was considered statistically significant.

Results

Of the 100 PD fluids, 87 were culture positive. Automated blood culture systems detected 87 episodes, whereas conventional centrifuge method detected only 53 episodes (P = 0.00001). Peritonitis due to Gram-negative organisms (62.3%) was higher than that of Gram-positive peritonitis (31.1%) and fungi (6.4%). Nineteen per cent episodes were constituted by relapse (9), refractory (4), recurrent (4) and repeat (2) peritonitis. Outcomes were analysed as recovery (77%), catheter removal (15%) and death (2.6%).

Conclusions

Direct inoculation of peritoneal fluid into automated blood culture bottles increases the positivity rate and also aids in the early detection of CAPD peritonitis, helping reduce morbidity and mortality of PD patients.

Using a multidisciplinary training program to reduce peritonitis in peritoneal dialysis patients

OBJECTIVES

The present study evaluated the tool used to assess patients' skills and the impact on peritonitis rates of a new multidisciplinary peritoneal dialysis (PD) education program (PDEP).

METHODS

After the University Hospital Ethics Committee approved the study, the educational and clinical records of PD patients were retrospectively analyzed in two phases. In phase I, an Objective Structured Assessment (OSA) was used during August 2008 to evaluate the practical skills of 25 patients with adequate Kt/V and no mental disabilities who had been on PD for more than 1 month. Test results were correlated with the prior year's peritonitis rate. In phase II, the new PDEP, consisting of individual lessons, a retraining schedule, and group meetings, was introduced starting 1 September 2008. Age, sex, years of education, time on PD, number of training sessions, and peritonitis episodes were recorded. Statistical analyses used t-tests, chi-square tests, and Poisson distributions; a p value of less than 0.05 was considered significant.

RESULTS

In phase I, 25 patients [16 men, 9 women; mean age: 54 ± 15 years (range: 22 - 84 years); mean time on PD: 35 ± 30 months (range: 1 - 107 months)] were studied. The OSA results correlated with peritonitis rates: patients who passed the test had experienced significantly lower peritonitis rates during the prior year (p < 0.05). In phase II, after the new PDEP was introduced, overall peritonitis rates significantly declined (to 0.28 episodes/patient-year from 0.55 episodes/patient-year, p < 0.05); the Staphylococcus peritonitis rate also declined (to 0.09 episodes/patient-year from 0.24 episodes/patient-year, p < 0.05).

CONCLUSIONS

The OSA is a reliable tool for assessing patients' skills, and it correlates with peritonitis rates. The multidisciplinary PDEP significantly improved outcomes by further lowering peritonitis rates.

Outcome and risk factors for mortality in pediatric peritoneal dialysis

BACKGROUND

The mortality rate among children requiring renal replacement therapy is higher than in children without end-stage renal disease (ESRD). Some factors, such as hypoalbuminemia, high peritoneal transport rate, age, malnutrition, cardiovascular disease, and recurrent peritonitis, appear to be associated with lower survival in adult peritoneal dialysis patients. Data regarding risk factors of mortality in children with continuous ambulatory peritoneal dialysis (CAPD) are limited. The aims of this study were to analyze the clinical characteristics of patients and investigate if routinely used laboratory and clinical variables are independent risk factors for mortality in children on CAPD.

METHODS

We performed a retrospective chart analysis of pediatric ESRD patients on CAPD between January 1997 and September 2008. 29 patients undergoing CAPD for more than 3 months were enrolled. An analysis was performed on clinical and biochemical variables for survivors and nonsurvivors to identify potential risk factors for mortality.

RESULTS

Mean age was 12.18 +/- 4.57 years. During the follow-up period, 8 patients transferred to hemodialysis and 13 patients received deceased donor renal transplantation. By the end of the study, 5 patients had died. Actuarial survival rate at 2 and 5 years was 96.55% and 91.19% respectively. The major complication during therapy was peritonitis (1 episode/57.79 patient-months). In the univariate analysis, younger age at initiation of dialysis, presence of comorbid disease, higher peritoneal transport rate, increased protein losses through peritoneal dialysis, high total daily protein loss, hypoalbuminemia, and hypophosphatemia were variables associated with mortality in pediatric CAPD patients. However, in the multivariate analysis, only low serum albumin (b = -2.089, p = 0.006; hazard ratio 8.06, 95% confidence interval 0.028 - 0.546) was independently associated with mortality.

CONCLUSION

Mortality was low in our pediatric patients receiving CAPD. Hypoalbuminemia showed a significant association with death in CAPD patients.