Emergency medicine updates: Spontaneous bacterial peritonitis

Spontaneous bacterial peritonitis (SBP) is a common infection in patients with cirrhosis and ascites and is associated with significant risk of mortality. Therefore, it is important for emergency medicine clinicians to be aware of the current evidence regarding the diagnosis and management of this condition.

This paper evaluates key evidence-based updates concerning SBP for the emergency clinician.

SBP is commonly due to Gram-negative bacteria, but infections due to Gram-positive bacteria and multidrug resistant bacteria are increasing. The typical presentation of SBP includes abdominal pain, worsening ascites, fever, or altered mental status in a patient with known liver disease; however, some patients may be asymptomatic or present with only mild symptoms. Paracentesis is the diagnostic modality of choice and should be performed in any patient with ascites and concern for SBP or upper gastrointestinal bleeding, or in those being admitted for a complication of cirrhosis. Ultrasound should be used to optimize the procedure. An ascites absolute neutrophil count (ANC) ≥ 250 cells/mm³ is diagnostic of SBP. Ascitic fluid should be placed in blood culture bottles to improve the culture yield. Leukocyte esterase reagent strips can be used for rapid diagnosis if available. While many patients will demonstrate coagulation panel abnormalities, routine transfusion is not recommended. Management traditionally includes a third-generation cephalosporin, but specific patient populations may require more broad-spectrum coverage with a carbapenem or piperacillin-tazobactam. Albumin infusion is associated with reduced risk of renal impairment and mortality.

An understanding of literature updates can improve the care of patients with suspected SBP.