K65.0/K65.8-9
DESCRIPTION
Infection of the peritoneum, usually secondary to a surgical cause such as perforated bowel. In this setting polymicrobial infection with anaerobes, Gram-positive cocci, and Enterobacteriaceae are usually found.
Primary or spontaneous bacterial peritonitis is much less common and usually complicates ascites in patients with portal hypertension. This is not usually polymicrobial but due generally to Enterobacteriaceae such as E. coli. Spontaneous bacterial peritonitis is often culture-negative but is diagnosed by ascitic neutrophil count >0.25 x 10⁹/L (250 cells/mm³).
GENERAL MEASURES
Secondary peritonitis
Intravenous fluids and nasogastric suction.
Prompt surgical intervention is essential.
MEDICINE TREATMENT
Empiric antibiotic therapy
For surgical causes of peritonitis:
- Amoxicillin/clavulanic acid, IV 1.2 g 8 hourly.
As soon as patient can tolerate oral medication:
- Amoxicillin/clavulanic acid, oral, 875/125 mg 12 hourly.
For spontaneous bacterial peritonitis:
- Ceftriaxone, IV, 1 g daily.
- Patients not responding to ceftriaxone after 48 hours, consult a specialist.
Switch to oral therapy when clinically appropriate according to culture or treat with:
- Ciprofloxacin, oral, 500 mg 12 hourly.
- Total duration of therapy: 14 days.