Microchimerism in Ghanaian children recipients of whole blood transfusion for severe anaemia

Background and objectives Transfusion‐acquired microchimerism ( TA ‐Mc) has been reported in major trauma but not in young children despite relative immunodeficiency who, in sub‐Saharan Africa, often suffer severe anaemia related to haemoglobinopathies or primary malaria infections. We examined the hypothesis that such massive red cell destructions might provide conditions favourable to TA ‐Mc, particularly when exposed to massive amounts of parasite antigens. Materials and Methods Twenty‐seven female children <5 years transfused with male whole blood for severe anaemia (13 with acute malaria and 14 with other causes) were retrospectively identified, and a blood sample was collected >6 months post‐transfusion. Four whole blood samples from paediatric females transfused with blood from female donors and five secondary school female students never pregnant, never transfused were used as negative controls. Results Nineteen patients (70%) carried male Mc with four (15%) having high levels of Mc (>100 genome equivalent of male cells/million of host cells) compared to three controls (37·5%). There was no difference in frequency or quantity of male Mc between paediatric patients with severe malaria and paediatric patients with other causes of severe anaemia. TA ‐Mc was not correlated with patient age, duration of whole blood storage or lymphocyte load transfused. After a median of 7 months post‐transfusion, acute malaria did not increase the frequency of TA ‐Mc. One negative control appeared to carry low‐level male cells. Conclusion Transfusion‐acquired microchimerism appears frequent in young children transfused with whole blood for severe anaemia.