Familial Neonatal Neutropenia with Maternal Leukocyte Antibodies

I SOIMMUNE leukocyte antibodies have been reported frequently since the initial communication of Dausset and Nenna’ in 1952. A large literature has accumulated and was recently fully reviewed by Walford,2 who listed over 500 reports. Most of these have been concerned chiefly with establishing the presence of such antibodies, the mechanisms by which they cause pathological effects being still controversial. Leukocyte antibodies have been implicated in the production of certain transfusion reactions,2 the L.E. phenomenon,4’5 and, more controversially, in certain neutropenic states.6’ Most frequently, isoimmunization to leukocytes has been described as the sequel of multiple transfusions.81’1#{176}”1 Payne and Rolfs have demonstrated the occurrence of leukocyte antibodies as a result of sensitization by fetal leukocytes.’2 These authors were unable to attribute any pathological effects of such antibodies on the bone marrow or white cell count of the infants. Neutropenia in the newborn has been sporadically reported in the past and these reports are summarized in two previous papers. 14 In 1954, Ballowitz and Ballowitz13 reported a case of erythroblastosis fetalis ( anti-C, anti-D) in which the child recovered following exchange transfusion. During the subsequent three months of its life the infant had a marked leukopenia. The maternal serum inhibited marrow cultures from subjects with C and D type blood. Other authors1 ”1 also postulated that neutropenic states in the newborn could be the result of the actions of maternal isoimmune antibodies on the fetus, but without direct evidence. Quite recently, Lalezari et al.14 reported a family with multiple case of neonatal neutropenia. A leukoagglutinin in the maternal serum was active against the leukocytes of the father and of three available children. A case involving a single infant was reported by Rossi and Brandt.17 The purpose of this paper is to report a similar family in which a further pregnancy presented the opportunity for studies which have helped to clarify the mechanism of the neonatal neutropenia.