Although the long term prognosis of SBP is guarded the short term prognosis is no longer considered dismal, as it was when the condition was first reported.
A recent review in the World Journal of Gastroenterology (available as free full text here) makes the following points:
Suspect SBP in patients with large volume ascites due to liver disease. It seldom occurs in patients with small volume ascites or in those with ascites unrelated to liver disease.
Clinical manifestations may be vague and indolent. Thirteen percent of patients have no direct symptoms. So, paracentesis is recommended for all cirrhotic patients admitted to the hospital with large volume ascites.
In patients diagnosed with peritonitis as defined as a peritoneal fluid PMN count of 250 or above additional peritoneal fluid tests (LDH, total protein and glucose), along with the use of imaging studies as clinically appropriate, can help distinguish SBP from secondary bacterial peritonitis due to perforation or other abdominal catastrophe.
Applying a drop of ascites fluid to the leukocyte esterase square of a urine dipstick may enable rapid detection of SBP and immediate institution of antibiotics while waiting on laboratory confirmation.
Five days of antibiotics seems to be as effective as longer courses.
Albumin administration is recommended for most patients---those with renal deterioration and those who undergo large volume paracentesis. 1.5 g/kg on day 1 and 1 g/kg on day 3 has been recommended in patients with renal dysfunction. (Albumin is not only a volume expander but also a drug. It binds inflammatory mediators).
The role of antibiotic prophylaxis has been defined.