Elevated alanine aminotransferase in blood donors: Role of different factors and multiple viral infections

Many different aetiological agents stimulate alanine aminotransferase (ALT) production. Viral markers and other aetiologies were investigated in 2166 individuals, randomly selected from 10 000 consecutive blood donors. Elevat ion of ALT was found in 10.8% of subjects. Grouping donors according to ALT level and correlating with, respectively, hepatitis B core antibody (HEBcA b), cytomegalovirus antibody alone, or associated with HBcAb, showed simila r findings (high ALT 11.1%, normal 11.60% high 85.4%, normal 81.4%; high 10 .2%, normal 11.0%, respectively). Hepatitis C virus (HCV) antibody was foun d to be significantly associated with elevated ALT levels (high 1.7%, norma l 0.26%). Other causes of ALT elevation were alcohol abuse (17%), obesity ( 25%) and dyslipidaemia (38%), but in 11% there was no obvious aetiology. Al though HCV is a rare cause of elevated ALT in blood donors, it seems to be the only virus, among those tested, to account for liver damage. This may b e due to the non-protective role of HCV antibody, the low specificity of AL T, or the pathogenic role of uninvestigated viruses.