Misleading results in the determination of haemolytic disease of the newborn using antibody titration and ADCC in a woman with anti-Lub.

ABSTRACT

The Lutheran blood group system consists of several genes of which Lua and Lub are the best characterized. Over 98% of the Western population is Lu (b+), and consequently antibody formation against Lub is rare. Cases reported in the literature suggest that the expression of Lutheran antigens on red cells of the newborn is weak, and Lutheran antibodies are not known to have caused severe haemolytic disease of the newborn. We describe a case of anti-Lub immunization during pregnancy. Despite increasing anti-Lub antibody titre and antibody-dependent, cell-mediated cytotoxic activity of the anti-Lub, two parameters associated with haemolytic disease of the newborn, the baby did not suffer from erythroblastosis.