We retrospectively studied 175 orthotopic liver transplants in 151 patients. Of the 151 patients, 59 (39.1%) were diagnosed as having cytomegalovirus (CMV) infection. The rate of infection in patients treated for rejection was 48.8% as compared to 26.2% in patients without rejection (P less than 0.01). Antirejection therapy was associated with culture-positive cases in 33 out of 43 patients as compared to 9 out of 16 patients who had CMV antibody titer elevations. Patients were treated with gancyclovir if they had simultaneous positive cultures from multiple sites and were seriously ill. Eighteen of the 19 patients thus treated had side effects, one of which was serious (bone marrow hypoplasia). Cultures became negative in 15 out of 17 (88%) of the surviving patients. Patient survival was similar to our overall survival rate of 87%.