INCIDENCE, ETHIOLOGY, SIGNIFICANCE AND CONSEQUENCES OF PERITONITIS CAUSED BY GRAM-NEGATIVE BACTERIA ON CAPD - EXPERIENCE OVER A PERIOD OF 13 YEARS AT ONE-CENTER

Peritonitis is a frequent complication of CAPD. The incidence of infec tion by gram-positive organisms has decreased over time, but that of g ram-negative infection has not. Their clinical importance is great. Th e objetive of this study of gram-negative peritonitis (GNP), was to es tablish methods to decrease their incidence and reduce their consequen ces. We have reviewed GNP over a period of thirteen years. 236 patient s by have been treated by CAPD for 6,624 patient-months. 66 episodes o ccurred in 49 patients. The incidence has been 1 episode/100 patient-m onths, 17 % of all episodes of peritonitis. The most frequent infectan ts have been Pseudomonas, E. Coli, Klebsiella and Proteus sp. Clinical ly, GNP were not different from other attaches of peritonitis. The pat ients with polycystic kidney disease suffered more GNP (p < 0,05) and elderly patints presented more frequent episodes caused by multiple or ganisms (p < 0,05). The system and type of catheter were not related t o a special risk of developing GNP. A break in the continuity of the p eritoneal closed circuit ocurred in 21 %. We observed that Pseudomonas and Serratia sp usually infected by a pathway around the catheter, an d were more resistant to empirical treatment (p < 0,05); they resulted in more frequent catheter loss (p < 0,001) than other organisms. 11 % of the patientes had to be trasferred to hemodialysis. There was no d irect GPN related mortality but the indirect mortality was 5%. We conc lude that gram negative peritonitis are here to stay and has not decre ased in the last 10 years. There are two populations of gram-negative organisms in terms of pathogenesis and follow-up: that of Pseudomona/S erratia sp and that of organisms of possible bowel origin. When infect ion involves the catheter, it should be immediately removed. We recomm end preventive treatment against these organisms (as well as gram-posi tive organisms) when a break of the peritoneal circuit occurs, with ac tive infection of the exit site. In the initial empirical treatment of an episode of CAPD peritonitis, antibiotics against these bacteria mu st be included.