Screening for IgA deficiency on the Olympus PK7100 by haemagglutination inhibition.

Severe or life-threatening anaphylactic reactions during blood transfusion to patients with anti-IgA, though infrequent, can be avoided by transfusing blood products prepared from IgA deficient donors. This report describes the development and use a passive haemagglutination assay adapted for use on the Olympus PK7100 blood group analyser. Donor plasma samples identified as being presumptive IgA deficient were further screened by a manual passive haemagglutination inhibition technique and finally confirmed by means of a quantitative enzyme-linked immunosorbent assay. Of 5723 donors tested simultaneously for IgA deficiency, blood grouping and red cell antibody screening, six (1 in 954) were confirmed as IgA deficient (i.e. < 100 ng/ml of IgA). The test is simple and cost effective and can be used to establish a database of IgA-deficient donors.