Orthotopic liver transplantation (OLT) is a successful therapy for patients with end-stage liver disease, and infection remains a significant cause of morbidity and mortality for patients undergoing this procedure. To assess humoral and cellular immunity markers as potential risk factors for development of infection, 46 consecutive liver transplant recipients (hepatitis C virus cirrhosis [n=17], alcoholic liver disease [n=15], hepatocellular carcinoma [n=9], autoimmune hepatitis [n=2], and other [n=3]) performed at a single center were prospectively studied. Maintenance therapy included tacrolimus (n=37) or cyclosporine (n=9) and prednisone. During follow-up, 27 patients had at least 1 episode of infection (58.7%). Pre-OLT immunoglobulin G (IgG) hypergammaglobulinemia (relative risk [RR] 2.78; 95% confidence interval [CI], 1.17-6.60, P=0.02), pre-OLT IgA hypergammaglobulinemia (RR 2.77, CI=1.24-6.19, P=0.012), and pre-OLT C3 hypocomplementemia (RR 3.02, CI=1.21-7.55, P=0.018) were associated with an increased risk for development of infection. Monitoring of Ig and complement levels might help to identify the risk of developing infection in OLT.