Neonatal alloimmune neutropenia due to immunoglobulin G antibodies against human neutrophil antigen-5a.
BACKGROUND
Neonatal alloimmune-mediated neutropenia (NAIN) due to maternal alloantibodies directed against one of the human neutrophil antigens (HNAs) can cause severe infections. NAIN has been described as caused by antibodies against HNA-1a, -b, -c, -2a, -3a, or -4a, but not by antibodies against HNA-5a.


RESULTS
Blood from a 3-week-old newborn and from his parents was sent to our laboratory because of suspicion of NAIN. Granulocyte-specific antibodies were present in the maternal antiserum and reactive with the paternal granulocytes. The specificity of the maternal alloantibodies was shown to be anti-HNA-5a by the monoclonal antibody immobilization of granulocyte antigens assay. The mother was genotyped HNA-5a negative, and the father was genotyped homozygous HNA-5a positive.


CONCLUSIONS
We identified a first case of NAIN due to maternal alloantibodies against HNA-5a.
Porcelijn
Leendert
L
Sanquin Diagnostic Services, University of Amsterdam, Amsterdam, the Netherlands, Amsterdam, the Netherlands. l.porcelijn@sanquin.nl
Abbink
Floor
F
Terraneo
Loes
L
Onderwater-vd Hoogen
Laura
L
Huiskes
Elly
E
de Haas
Masja
M
D000328:Adult; D000918:Antibody Specificity; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007231:Infant, Newborn; D007518:Isoantibodies / Q000097:blood*; D007519:Isoantigens / Q000276:immunology*; D008297:Male; D009503:Neutropenia / Q000209:etiology*; D009504:Neutrophils / Q000276:immunology*; D011247:Pregnancy
C451326:5a antigen; D007074:Immunoglobulin G; D007518:Isoantibodies; D007519:Isoantigens