A case of continuous ambulatory peritoneal dialysis peritonitis with an uncommon organism and an atypical clinical course.

This report describes a 46-year-old patient who experienced an atypical course of peritonitis while undergoing continuous ambulatory peritoneal dialysis (CAPD). The first sign of peritonitis was progressive impairment of ultrafiltration with increasing fluid absorption. The patient came to the center after 5 days with leg edemas and 645 leukocytes/microL in the first dialysate outflow. On the same day, the dialysate cell count decreased to 208/microL. During the following days, ultrafiltration failure persisted despite spontaneous normalization of PD-fluid leukocytes. No other clinical symptoms were observed, and the serum C-reactive protein (CRP) level remained normal. Magnetic resonance peritoneography and abdominal radiograph did not show dislocation of the catheter, a dialysate leak, or other causes of ultrafiltration failure. At day 14, fever, diarrhea, and an elevated serum CRP level occurred. Dialysate cultures taken on days 8, 11, and 14 showed growth of NEISSERIA: sicca. After initiation of antibiotic therapy with levofloxacine on day 14 ultrafiltration, clinical symptoms and serum CRP normalized within 3 days. In conclusion, Neisseria sicca should be considered as a rare cause of PD peritonitis. Our case report further illustrates the importance of ultrafiltration failure as an early and main symptom of peritoneal inflammation. The frequently used peritonitis criteria may not apply to cases of mild PD peritonitis.