Spontaneous Bacterial Peritonitis
Spontaneous bacterial peritonitis (SBP) is infection of ascitic fluid without a surgically treatable intra-abdominal source, usually in advanced cirrhosis; diagnose it promptly with ascitic neutrophil counting and treat immediately with context-appropriate antibiotics, renal-protective albumin when indicated and specialist follow-up.
Definition
Spontaneous bacterial peritonitis is infection of ascitic fluid in the absence of an intra-abdominal source requiring surgery. In cirrhosis, an ascitic fluid neutrophil count of 250 cells/mm³ or more is the diagnostic treatment threshold, with or without a positive culture.
First principles
SBP is infection without perforation
Portal hypertension, gut-barrier dysfunction and impaired immune defence allow enteric bacteria to translocate into ascitic fluid. SBP is defined by infection of ascites in the absence of an intra-abdominal source that needs surgery. Perforation, abscess or another surgically treatable source instead indicates secondary peritonitis and needs a different pathway.
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