Viral infections in transfusion-dependent patients with beta-thalassemia major: the predominant role of cytomegalovirus.

For 9 months, 38 transfusion-dependent patients with beta-thalassemia, ranging in age from 3.4 to 19.1 years, were observed for serologic evidence of viral infections, by the collection of serial serum samples. Seventy-six age-matched healthy subjects, two for each patient, were followed as controls. Samples taken at the beginning, middle, and end of the study were tested against 18 viral antigens by complement fixation (CF). In addition, tests for antibodies to HIV, Epstein-Barr virus, hepatitis A virus, and markers for hepatitis B virus were performed. When changes in the antibody titer on CF tests (greater than or equal to 2-fold increase or decrease) or persistently high titers (greater than or equal to 64) were revealed, specific enzyme immunoassays (EIAs) for IgM and IgA antibodies were performed concomitant with CF tests in all sera. When symptomatic infections occurred, viral cultures and/or direct detection of antigens were carried out by immunofluorescence methods, EIA, or latex agglutination tests. Thalassemic patients and controls had similar (p greater than 0.05) overall rates of serologically confirmed viral infections (53 versus 132), but the former group had a higher (p less than 0.01) incidence of cytomegalovirus (CMV) infections (9 versus 4). CMV infections were associated in the thalassemic patients with hepatitis (2 cases), lymphadenitis (2 cases), and upper respiratory tract infection (1 case), while the remaining cases of CMV had a subclinical course. Moreover, the thalassemic patients had a lower (p less than 0.01) incidence of symptomatic infections (27 versus 110) than controls. Therefore, this study showed that both symptomatic and subclinical CMV infections may occur often in thalassemic patients, who otherwise have subclinical viral infections at an overall rate similar to that in healthy subjects.