Peritonitis is present if a patient has at least 2 of the following criteria: Clinical features consistent with peritonitis (eg, abdominal pain, tenderness, and / or cloudy dialysis effluent) Dialysis effluent WBC > 100 / mcL with > 50% polymorphonuclear cells after a dwell time of at least 2 hours Positive peritoneal fluid culture (1) Gram stain is often unrevealing, but cultures are positive in > 90%.