Relationships between Climate Factors and Peritonitis In CAPD Patients

Park, Young Ju; Song, Joon Ho; Kim, Gyeong A; Lee, Seoung Woo; Kim, Moon Jae

Abstract

Peritonitis is one of the major complication of continuous ambulatory peritoneal dialysis (CAPD) and the most common cause of hospital admission and for termination of peritoneal dialysis. We retrospectively analyzed the incidences and causative organisms of CAPD peritonitis according to season/month of the year under the hypothesis that climate factors, increased temperature and humidity, may changes the incidences and causative organisms of peritonitis. There were a few studies about this issue and in most cases the result was inconclusive because of the limitation in the limited range of climate factors such as temperature and humidity. Wide annual differences of temperature (-3.4-25.4 degrees C) and humidity (61-81%) may affect the rate of peritonitis episode in the area where the current study was performed. Data from 80 patients(49 male, 31 female), with a mean age 48.3+/-14.5 years and mean CAPD period 14.0+/-9.0 months, followed from September 1996 to July 1999, were reviewed. Fifty-three cases of peritonitis were found in 1,123 patient-months, a rate of 0.56 episode/patients- year, and 0.047 episode/patient-month. The months in which the incidence of peritonitis above average was March (5.05%), May(7.96%), July (10.8%), August (6.25%), September (6.06%). The incidence of peritonitis was the lowest in November (1.31%). The incidence in hot season (May-September : average temperature for three years 21.9degrees C, humidity 74%) was 0.065 episodes/patient-month, which was significantly higher than in cold season (October-February : 5.9degrees C, 64.4%)(p<0.05). Average temperature for three years in the study area was 13.2degrees C with maximal temperature of 25.4degrees C (August) and minimal of -3.4 degrees C (January). Average humidity for three years in the study area was 68.4% with maximal humidity of 81% (July) and minimal of 61% (April). The incidence of peritonitis paralleled with temperature and humidity, highest in July (0.080/pt-month) and lowest in November (0.013/pt-month) and were directly correlated with temperature (r=0.53, p<0.05) and humidity (r=0.59, p<0.05). Among 53 episodes of peritonitis, gram positive peritonitis, gram negative peritonitis and culture negative peritonitis were 36.9%, 15.0% and 45.2%, respectively. From March to August, gram positive peritonitis was 50% and culture negative peritonitis was 42.4%. From September to February, culture-negative peritonitis was 52.9% and gram negative peritonitis organisms was 29.4%. In contrast to gram positive organisms which showed increased in hot weather, gram negative organisms showed uniform distribution throughout the year. There were no significant monthly differences in peritoneal fluid WBC count on admission and negative conversion period of that. Our data suggest that high temperature and humidity can adversely affect the incidence of CAPD peritonitis and may change the distribution of causative organisms.