HEMOLYTIC-DISEASE OF A NEWBORN DUE TO ANT I-D ANTIBODIES IN A D(U)-POSITIVE MOTHER

The Rhesus blood group D(u) is a collective name for less antigenic va riants of the Rhesus antigen D. D(u)-positive individuals (0.6% of the caucasians) can produce anti-D-antibodies if sensitized. We report on a newborn girl with haemolytic disease; she was the second child of a D(u)-positive mother, whose erythrocytes were Tippett class VI. Durin g pregnancy anti-D-titres up to 1:64 were found. In the newborn, the d irect Coombs test was positive due to anti-D-IgG. The girl had to be t ransfused repeatedly for anemia, and needed phototherapy for hyperbili rubinemia. The etiology of the D(u)-status is not entirely clear yet. A mosaic structur of the D antigen is discussed as well as an allelic interaction or a decreased expression of D antigen sites on the erythr ocyte. There also is uncertainty about adequate postpartal anti-D-prop hylaxis in maternal D(u)-status. The German Guidelines for Transfusion Medicine comment only indirectly: when receiving blood, D(u)-positive individuals should be treated the same as Rhesus-negative persons. In fact, D(u)-positive mothers in Germany often receive one dose of anti -D-immunoglobuline without further testing as in Rhesus-negative mothe rs.