[A rare case illustrating the difficulty of diagnosing and treating elderly patient with CAPD-related peritonitis caused by the perforation of sigmoid colon diverticulum].

A 67-year-old man was admitted with abdominal pain on April 23, 2000. Continuous ambulatory peritoneal dialysis (CAPD)-related peritonitis was diagnosed. Administration of antibiotics for five days obtained no improvement. Therefore the peritoneal catheter was removed on April 28th. Although his condition became settled, C-reactive protein remained positive. Moreover, two kinds of bacilli were detected from the CAPD fluid, just before the catheter was removed. As abnormalities in the colon were possible, an enema examination was performed on May 23rd. A constriction and several diverticula of the sigmoid colon were detected. High grade fever appeared on May 23rd, and the patient complained of abdominal pain the next day. As there was no improvement, we performed enhanced computed tomography and detected an abscess in the Douglas pouch on May 29th. The abscess was resected on the same day, and he was discharged. The number of patients with chronic renal failure has increased in recent years. Although hemodialysis has been the treatment of choice, peritoneal dialysis should be considered. More investigations into complications created by peritoneal dialysis are required, especially in elderly people who seldom show symptoms of CAPD-related peritonitis until they reach a critical condition. If peritoneal dialysis is being performed and inflammation reactions continue, it is necessary to examine the patient for perforated peritonitis and abscess formation.