Hemolytic disease of the newborn due to Anti-Goa

Abstract

Partial D antigen describes red cells which lack one or more of the different epitopes that are usually present on the red cells of most D-positive people. Subjects with partial D may produce antibodies against the epitopes which are missing. Anti-Goa is expressed in D partial red blood cells (class IVA), and the presence of this antibody subdivides this subjects into Go(a+), mainly Blacks and Go(a-), found only in whites. We present a case of Anti-Goa detected in a newborn from Senegalese parents who presented a positive direct antiglobulin test (DAT) (IgG +/C3d -). His blood group was O Rh positive (cDe/cDe). At birth, bilirubin level was 4.6 mg/dl, and the remaining laboratory parameters were normal. Likewise, clinical examination detected no abnormalities. Mother was blood group O Rh positive (cDe/cde). Antibody screening test performed in mother's serum was negative either with normal or enzyme-treated cells. Father was also blood group O Rh positive (cDe/cde). A crossmatch using mother's serum and father's red blood cells was positive in the indirect antiglobulin test. These results did not change when the serum was treated with DTT, suggesting that the antibody was IgG. The different IgG subtypes were studied resulting IgG4 (Table I). Identification Blood Group AST DAT Serum Eluate Mother O positive (cDe/cde) Positive Positive (IgG) Anti-Goa Anti-Goa Father O positive (cDe/cde) Negative Negative Patient O positive (cDc/cOe) Negative Positive (IgG) Negative Anti-Goa AST: Antibody screening test; DAT: Direct antiglobulin test Mother's serum and red blood cells were sent to a reference laboratory (Ortho Diagnostic Systems) detecting the presence of Anti-Goa antibody both in serum and eluate. Otherwise, the father's red blood cells were Go(a+) The hemolytic reaction observed was mild, and no treatment was needed. The patient recovered completely and was discharged from the hospital a few days later with good clinical status and normal hematological values. Anti-Goa appears approximately in 2% of Blacks and it is has been described associated to hemolytic disease of the newborn and transfusional hemolytic reactions. This case of Anti-Goa shows the characteristics of hemolytic activity previously described. However, this is the first case detected in Spain, and highlights the special difficulty in the detection of these antibodies.