HBsAg seropositive status and survival after renal transplantation: meta-analysis of observational studies.

The natural history of hepatitis B virus (HBV) infection after renal transplantation (RT) remains unclear. We conducted a systematic review of the published medical literature on the impact of HBV surface antigen (HBsAg) seropositivity on survival of RT recipients. We used the random effects model of DerSimonian and Laird to generate a summary estimate of the relative risk for mortality and graft loss in HBsAg positive RT recipients across the published studies. We identified six observational studies (6050 unique patients); all of them being cohort, retrospective studies. Pooling of study results demonstrated that HBsAg in serum was an independent and significant risk factor for death after RT; the summary estimate for relative risk was 2.49 with a 95% confidence interval (95% CI) of 1.64-3.78. A test for homogeneity of the relative risk across the studies gave a p-value of <0.0001. HBsAg seropositivity was an independent and significant risk factor for graft failure after RT; the summary estimate was 1.44 with a 95% CI of 1.02-2.04 (homogeneity test, p <0.0001). This meta-analysis shows that HBsAg positive RT recipients have an increased risk for mortality and graft failure compared to seronegative patients.