Spontaneous Bacterial Peritonitis

Ascitic fluid infection without an evident intra-abdominal source, most often in patients with liver cirrhosis and ascites

Prompt paracentesis before starting antibiotics is ideal

Send fluid for analysis and two 10ml vials (aerobic and anaerobic) for culture and sensitivity

Rule out secondary peritonitis from a perforated viscus (2 of total protein > 10 g/L, glucose < 2.8 mmol/L, LDH > ULN for serum is a strong predictor for secondary peritonitis, as is polymicrobial infection)

Start empiric antibiotics if one or more of:

  • temperature >38°C

  • abdominal pain/tenderness

  • change in mental status

Otherwise, it is reasonable to wait for ascitic fluid analysis, and starting antibiotics if PMN count is ≥ 250 cells/uL

Also treat symptomatic patients with bacterascites (bacterial growth from ascitic fluid) with a PMN count <250 cells/uL

Duration of Therapy

Can extend up to 10 days if bacteremic and depending on clinical response

Empiric Therapy

Cefotaxime 2g IV Q8H is also recommended but less cost-effective

3rd-gen cephalosporins are recommended over broader therapies even if on SBP prophylaxis

Tailor to culture and sensitivity results, although cultures may be negative if low volume of ascites was sent

For long-term SBP prophylaxis indicated, see link below