Management of Spontaneous Bacterial Peritonitis

Diagnosis and Treatment

The European Association for the Study of the Liver recommends that a response tap be performed 48 hours after initiating antibiotic therapy for suspected spontaneous bacterial peritonitis (SBP) to confirm treatment efficacy by demonstrating a decrease in ascitic fluid neutrophil count 1
SBP is diagnosed when the ascitic neutrophil count exceeds 250 cells/mm³ in the absence of an intra-abdominal surgically treatable source of infection 1
Approximately 15% of hospitalized cirrhotic patients with ascites have SBP, making diagnostic paracentesis mandatory on admission and whenever clinical deterioration occurs 2, 1
Patients with "culture-negative neutrocytic ascites" (neutrophil count >250 cells/mm³ with negative cultures) should be treated identically to culture-positive SBP, as both carry similar morbidity and mortality 1

A decreasing neutrophil count on the response tap indicates appropriate antibiotic selection and treatment response, allowing continuation of the current antibiotic regimen for the full 5-day course 1
A stable or rising neutrophil count suggests treatment failure, necessitating broader antibiotic coverage or investigation for secondary bacterial peritonitis from a perforated viscus or other intra-abdominal pathology 1
If polymicrobial infection is identified on culture, this strongly suggests secondary bacterial peritonitis rather than SBP, requiring surgical evaluation and different management 1

The American Association for the Study of Liver Diseases advises against delaying the response tap beyond 48 hours, as early identification of treatment failure is critical for patient survival given the 20% in-hospital mortality of SBP even with prompt treatment 1
The European Association for the Study of the Liver recommends against skipping the response tap in patients who appear clinically improved, as clinical symptoms may not reliably correlate with microbiological response, and subclinical treatment failure can lead to complications 1
Paracentesis can be safely performed despite abnormal coagulation parameters, with bleeding complications occurring in <1 in 1,000 procedures, according to the European Association for the Study of the Liver 2