Neonatal alloimmune thrombocytopenia and neutropenia associated with maternal human leukocyte antigen antibodies

Abstract

Neonatal thrombocytopenia or neutropenia may result from passive transfusion of maternally derived antibodies. Antibodies against platelet antigens are commonly associated with neonatal alloimmune thrombocytopenia (NAIT), and anti-neutrophil antibodies are frequently identified in alloimmune neonatal neutropenia (ANN). Combined alloimmune cytopenias in the newborn are rarely reported; even fewer reports document human leukocyte antigen (HLA) antibodies as a potential cause of neonatal thrombocytopenia or neutropenia. We describe neutropenia and thrombocytopenia in a newborn associated with markedly elevated maternal HLA antibodies in the absence of anti-neutrophil or anti-platelet antibodies to highlight consideration of HLA antibodies in the pathogenesis of ANN and NAIT.

Vaccine-induced antibodies linked to bovine neonatal pancytopenia (BNP) recognize cattle major histocompatibility complex class I (MHC I)

“…The NAIT syndrome is caused by diaplacental transmission of maternal antibodies that are directed against paternal alloantigens on hematopoietic cells. While alloantibodies in most NAIT cases are directed against human platelet antigen (HPA) [35], some cases of NAIT have been linked to human leukocyte antigens (HLA), the human homologue to cattle MHC I (BoLA) [36]. In humans, antibodies can freely cross the placenta barrier so that alloantibodies can affect the fetus in utero.…”

Alloantibodies against MHC Class I: A Novel Mechanism of Neonatal Pancytopenia Linked to Vaccination

“…In humans, MHC class I alloantibodies in individual cases of fetal/neonatal alloimmune thrombocytopenia (FNAIT) have been reported a number of times during the past decades (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25). In addition to thrombocytopenia, the presence of an associated neutropenia is noticed in a few cases (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28). These Abs are sometimes detected at the same time as other HPA Abs commonly involved in FNAIT (27)(28)(29).…”

“…In addition to thrombocytopenia, the presence of an associated neutropenia is noticed in a few cases (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28). These Abs are sometimes detected at the same time as other HPA Abs commonly involved in FNAIT (27)(28)(29). Although HLA class I Abs are commonly encountered in the mothers of FNAIT cases (30), their role as the main trigger remains controversial (17,31,32).…”

Neonatal alloimmune thrombocytopenia caused by anti‐HLA‐A24 alloantibodies

“…Sporadic cases describing NAIT caused by anti‐HLA class I antibodies contradict these studies (4). Case reports of neonatal alloimmune thrombocytopenia and neutropenia associated with maternal anti‐HLA class I antibodies are rarely reported (5).…”