Renal dysfunction is the most important independent predictor of mortality in cirrhotic patients with spontaneous bacterial peritonitis

Background & aims: Spontaneous bacterial peritonitis (SBP) is the most common infection among patients with cirrhosis. To improve stratification of patient care, we performed a systematic review to identify the most robust predictors of mortality in cirrhotic patients with SBP.

Methods: We reviewed prognostic studies (English language only) of adult patients with SBP, defined as a polymorphonuclear ascitic fluid cell count of 250 cells/mm(3) or more, with or without positive results from culture of ascitic fluid. We reviewed only studies that performed survival and multivariate analyses and reported in-hospital or mortalities within 30 days.

Results: Of 2008 available references, 18 were included in the study (median, 115 patients per trial). The median age of patients was 56 years (68% male). The most common predictors of death were renal dysfunction, lack of SBP resolution, immunosuppressive factors, and hospital-acquired SBP. Sensitivity analysis using the 12 best-quality studies identified renal dysfunction and levels of blood urea nitrogen and creatinine as the most important variables. The mortality rate among patients with renal dysfunction was 67%, compared with only 11% of patients who maintained normal renal function.

Conclusions: Renal dysfunction is the main prognostic factor for cirrhotic patients with SBP, followed by the MELD score. Further studies are needed to determine whether these factors identified retain prognostic value in high-risk patients who receive albumin. Risk stratification might be used to select additional treatments, such as early vasoconstrictor therapy, for the highest-risk group.