Abstract
♦ Objectives
To evaluate the distribution of peritonitis incidence and assess the usefulness of patient-specific peritonitis rates in children.
♦ Design
49 children on automated peritoneal dialysis (PD) followed during a 2-year observation period.
♦ Setting
Single-center, academic children's hospital.
♦ Patients
49 children aged 2 months to 18 years; 24 prevalent, 25 incident during the observation period. Cumulative observation time was 639 patient-months.
♦ Main Outcome Measures
Cohort-specific peritonitis incidence, median patient-specific peritonitis incidence, mean peritonitis incidence by gamma-Poisson (negative binomial) modeling, peritonitis-free survival by Kaplan–Meier life-table analysis.
♦ Results
68 new peritonitis episodes and 21 relapses occurred in 27 patients. The distribution of patient-specific peritonitis incidence was bimodal, with a large group experiencing no or very few episodes, and another cluster around 1 episode per 6 – 9 months. Overall cohort-specific peritonitis incidence was 1.28, median subject-specific incidence 0.99, and mean incidence according to negative binomial modeling 1.04 (95% confidence interval 1.02 – 1.06) episodes per patient-year. Median peritonitis-free survival time was 6.9 months. In those patients who developed peritonitis, subject-specific peritonitis incidence was inversely correlated with patient age (r = –0.42, p < 0.05) and duration of chronic PD at last observation (r = –0.42, p < 0.05).
♦ Conclusions
Since the distribution of peritonitis in children is non-Gaussian, the average risk of peritonitis is more accurately expressed by the median of the individual subject-specific peritonitis rates or by the mean incidence estimate obtained by the negative binomial distribution model. The assignment of a personal peritonitis risk to each patient permits risk factor analysis by routine statistical methods, even in smaller populations.
Get full access to this article
View all access options for this article.