The Role of Rifaximin in the Primary Prophylaxis of Spontaneous Bacterial Peritonitis in Patients With Liver Cirrhosis

Abstract
Primary prophylaxis of spontaneous bacterial peritonitis (SBP) may provide a survival advantage in cirrhotic patients with ascites and has become an integral part of clinical practice. Rifaximin is a poorly absorbable antibiotic with a broad spectrum of antibacterial action and has low risk of introducing bacterial resistance. To determine whether rifaximin is associated with decreasing the risk of SBP and improving transplant-free survival in cirrhotic patients with ascites. The medical records of all adult patients with liver cirrhosis and large ascites justifying paracentesis evaluated in our clinic (2003 to 2007) were reviewed. Patients were stratified into 2 groups by the use of rifaximin. Patients were excluded if they had received another antibiotic for SBP prophylaxis or had a history of SBP before rifaximin therapy. A total of 404 patients were included, of whom 49 (12%) received rifaximin. The rifaximin and nonrifaximin groups were comparable with regards to age, sex, and race. The median follow-up time was 4.2 [1.0, 17.1] months. During this time period, 89% of patients on rifaximin remained SBP free compared with 68% of those not on rifaximin (P=0.002). After adjusting for Model of End-Stage Liver Disease score, Child-Pugh score, serum sodium, and ascitic fluid total protein, there was a 72% reduction in the rate of SBP in the rifaximin group (hazard ratio=0.28; 95% confidence interval, 0.11-0.71; P=0.007). The group treated with rifaximin also demonstrated a transplant-free survival benefit compared with those not on rifaximin (72% vs. 57%, P=0.045). Intestinal decontamination with rifaximin may prevent SBP in cirrhotic patients with ascites. Prospective randomized controlled trials are needed to confirm this finding.