Oral Antibiotic Prophylaxis Reduces Spontaneous Bacterial Peritonitis Occurrence and Improves Short-Term Survival in Cirrhosis: A Meta-Analysis

OBJECTIVES: Spontaneous bacterial peritonitis (SBP) is a serious complication of advanced liver disease resulting in high mortality rates. Although studies that assessed the use of oral antibiotics in advanced liver disease demonstrated a clear benefit in reducing the risk of recurrent peritonitis, it is unclear whether mortality rates are similarly affected by this practice. The goal of this study was to determine whether oral antibiotic therapy provides a survival benefit for patients with advanced cirrhosis and ascites. Through subgroup analysis, we also evaluated the effect of prophylactic oral antibiotic therapy on the prevention of SBP and the incidence of all infections (including SBP) when compared with non-treated or placebo controls. METHODS: We conducted a comprehensive search of the Cochrane Database of Systematic Reviews, MEDLINE (1966 to May 2008), bibliographies of retrieved trials, and reports presented at major scientific meetings. Eligible studies included prospective, randomized controlled trials comparing high-risk cirrhotic patients receiving oral antibiotic prophylaxis for SBP with groups receiving placebo or no intervention. Dichotomous outcomes were reported as relative risk (RR) with 95% confidence intervals (CIs). RESULTS: Eight studies with a total of 647 patients were identified and included in this analysis. The combined analysis showed an overall mortality benefit (RR=0.65; 95% CI, 0.48-0.88) for treatment groups. The overall mortality rate was 16% (52/324) for treated patients and 25% (81/323) for the control group. Groups treated with prophylactic antibiotics also demonstrated a lower incidence of all infections ( including SBP) of 6.2% as compared with the control groups with a rate of 22.2% (RR=0.32; P<0.00001; 95% CI, 0.20-0.51). Subgroup analysis showed a survival benefit at 3 months (RR=0.28; P=0.005; 95% CI, 0.12-0.68). CONCLUSIONS: Antibiotic prophylaxis improved short-term survival in treated patients when compared with untreated control groups and reduced the overall risk of infections, including SBP, during follow-up. In summary, antibiotic prophylaxis should be considered for high-risk cirrhotic patients with ascites.