Renal retransplantation can be hampered by the presence of anti-HLA alloantibodies. Previous studies have documented in vitro and in vivo suppression of these antibodies by intravenous immunoglobulins (IVIg). We conducted a randomized study in 41 patients, who have received a second cadaveric transplant between 1989 and 1994. They all were treated with a quadruple-immunosuppressive protocol. In addition, 21 patients received 0.4 g/kg/day of IVIg, on the first 5 days after transplantation. The two groups of patients were identical for age, sex, duration of the first graft, duration of cold ischemia, anti-HLA sensitization, HLA matching, the number of acute rejection episodes, and the incidence of cytomegalovirus infection. The 5-year survival rate was significantly higher in the group of patients treated with IVIg: 68% versus 50% in the control group. The only significant factor associated with IVIg infusion and better survival was a shorter delay of graft function (3.4 +/- 1.0 days versus 9.9 +/- 1.6 days). In conclusion, this randomized study demonstrates that IVIg treatment is associated with better long-term graft survival in retransplanted patients. This beneficial effect may be related to a long-lasting immunosuppressive effect of IVIg and/or to an early protective effect of the graft against ischemia.