[Red cell autoimmunization in a "normal" population. 63 cases (author's transl)].

Anti-red auto-antibodies were found in 69 out of 892 000 blood donors aged between 20 and 60 years, 63 of whom were followed for up to five years. This would suggest an overall incidence of 1 in 13 000 members of a "normal" population. Uncontrolled methyl-dopa treatment could be incriminated in 25% of cases. Only 10% of autoimmune subjects had slight confirmed anaemia, but 72% had biological evidence of red cell destruction (i.e. hyper-reticulocytosis, elevated serum bilirubin levels and shortened red cell life span), which demonstrates the presence of subclinical autoimmune haemolytic disease in apparently normal people. The anti-red cell auto-antibodies were of the IgG type in 97% of the subjects and were associated with various anti-tissue antibodies in 41%, thus pointing to a multisystem autoimmune disorder. In most cases the abnormality persisted or spontaneously regressed during the observation period, but long-term follow-up is required to determine whether asymptomatic red cell autoimmunization is harmless or potentially dangerous.