Serological monitoring of thalassaemia major patients for transfusion associated viral infections.

A total of 39 patients with thalassaemia major who received multiple blood transfusions were followed up clinically and serologically for 3 successive years (1993, 1994, 1995). They were screened for hepatitis B surface antigen (HBsAg), and antibodies to hepatitis B core (HBc-total), hepatitis C virus (HCV), human immunodeficiency virus I and II (HIV-I/II) and cytomegalovirus (CMV-total). In spite of transfusing HBsAg screened (by third generation ELISA) blood from voluntary non-remunerated donors, there was a significant increase of HBsAg positivity (P < 0.001) from 17.9 per cent (1993) to 35.9 per cent (1994) to 69.2 per cent (1995). This was probably due to the prevalence of undetectable HBV infection in the population. Anti HBc was present in 17 (43.6%), 14 (35.9%) and 16 (41%) patients in consecutive years. An increase in the units of blood transfused was observed every year. Blood units were not screened for anti HCV antibodies but a gradual increase in positivity [9 (23%), 12 (30.7%) and 14 (35.9%) patients] was seen in consecutive years. Anti-HIV antibodies were found in a 16 yr old male who was included in the study without any clinical evidence of AIDS. Anti CMV antibody was found in 30 (76.9%), 32 (82%) and 29 (74.3%) patients without any apparent clinical infection. Some patients showed change of antibody pattern (from negative to positive or vice versa) and a few patients showed inconsistent results probably due to immune modulation. Recruitment of 'repeat' non-remunerated voluntary blood donors may reduce the risk of high HBV transmission.