Management and outcome of 35 cases with foetal/neonatal alloimmune neutropenia

Abstract

More than half (21) of the 35 cases of FNAIN presented with infections and most implicated were HNA-1a, HNA-1b and HNA-2. Treatment with antibiotics seemed adequate. A neonatal neutropenia workflow model for use in neonatal intensive care units is presented.

Neonatal Alloimmune Neutropenia

“…Most diagnosed NAIN cases, being the cases with clinical symptoms, showed ANCs below 500/μl. A high incidence of miscarriage was reported by Lalezari et al [4] (19%) and Bux et al (50%) [15]. In our series, ‘only' 2 (6%) of 35 women experienced a miscarriage [16].…”

“…In some cases NAIN is caused by isoantibodies, if a mother is lacking a complete HNA system-carrying structure (e.g. anti-FcγRIIIb isoantibodies or HNA-2 antibodies) [15]. …”

“…In the published series, percentages for NAIN in first pregnancies vary between 5 and 40% [4,15,16]. This implies that maternal immunization can take place during pregnancy or even before the first pregnancy.…”

“…Maternal sensitization to HNA-1a to HNA-1d, FcγRIIIb, HNA-2, HNA-3a, HNA-3b, HNA-4a, HNA-4b, and HNA-5a leading to NAIN have all been reported. Most cases are caused by antibodies specific for the FcγRIIIb located antigens HNA-1a and HNA-1b, followed by anti-HNA-2 and anti-FcγRIIIb [3,15,16]. The other antibody specificities are only rarely detected.…”

“…Bux et al [15] detected 11 (1.1%) granulocyte-specific antibodies in 1,016 unselected samples postnatally drawn. Four (0.4%) of these 11 antibodies, were allogeneic and specific for one of the known HNAs.…”