Aseptic peritonitis in a peritoneal dialysis patient

Patients who have repeatedly sterile peritoneal fluid cultures despite elevated peritoneal fluid white cell count should be evaluated for disorders other than usual bacterial peritonitis. Intra-abdominal pathology was responsible for less than 6 percent of cases of peritonitis. Still, the clinical outcome is these situations are much worse than in other commoner causes.

A 25-year-old male non-diabetic patient in PD started his complains with diffuse abdominal pain with spontaneous remissions and exacerbations, anorexia and vomiting with 3 days evolution. Laboratory results with persistent culture-negative peritoneal fluid results seemed compatible with the diagnosis of aseptic peritonitis. However, clinical status progression and peritoneal fluid amylase levels above 50 UI/L led to perform an abdominal ultrasound that showed a painful non-compressible tubular structure with a diameter of >6 mm at the base of the cecum. The patient was then submitted to a laparotomy with appendix removal.

When assessing a patient with abdominal pain and clear or cloudy but aseptic peritoneal liquid, causes other than peritonitis should be excluded. Under antibiotic therapy, their clinical picture and evolution may be masked, delaying surgical resolution. In appendicitis, this delay may lead to perforation and consequent faecal peritonitis. All patients should be screened for peritoneal fluid amylase levels in order to differentiate bacterial peritonitis from intra-abdominal pathology. In all cases similar to the present one, an abdominal US/CAT scan should be promptly made.