An acute haemolytic transfusion reaction due to anti-Jk a

The Kidd system antibodies are characteristicallydifficult to detect. They show variability in immunoglobulinclass, subclass and serological characteristics. They aregenerally detected by an antiglobulin test, using apolyspecific antiglobulin or complement antiserum. Often,the antibodies are only detected using cells with a doubledose (homozygous) expression of Kidd antigens, enzyme-treated cells or by using sensitive immunohaematologicaltechniques.