Neonatal alloimmune thrombocytopenia due to anti-HPA 5a in a HPA-5a homozygous neonate

R Porta; P Serrano; A Paltrinieri; G Ristic; C Canals; M Lozano

doi:10.1016/j.transci.2020.102880

Neonatal alloimmune thrombocytopenia due to anti-HPA 5a in a HPA-5a homozygous neonate

Transfus Apher Sci. 2020 Dec;59(6):102880. doi: 10.1016/j.transci.2020.102880. Epub 2020 Jul 22.

Authors

R Porta¹, P Serrano², A Paltrinieri², G Ristic², C Canals³, M Lozano⁴

Affiliations

¹ Hospital Dexeus, Pediatrics-Neonatology, Barcelona, Catalonia, Spain. Electronic address: roser.porta@quironsalud.es.
² Hospital Dexeus, Pediatrics-Neonatology, Barcelona, Catalonia, Spain.
³ Immunohematology Laboratory. Banc de Sang i Teixits. Barcelona, Catalonia, Spain.
⁴ Hospital Dexeus, Transfusion Department, Barcelona, Catalonia, Spain.

PMID: 32763115
DOI: 10.1016/j.transci.2020.102880

Abstract

The most frequently involved antigen in severe fetal and neonatal alloimmune thrombocytopenia (FNAIT) is the human platelet antigen 1a. Cases of FNAIT caused by HPA-5a antigen are extremely rare, and usually not severe. We report a case of FNAIT caused by anti-HPA antibodies directed to the HPA-5a antigen. The thrombocytopenia was moderate with a minimal platelet count of 36 × 10⁹/L by day 3, and spontaneously resolved by day 10. The pregnancy had been obtained by in vitro fertilization using embryo donation, creating a complete genetic disparity between the HPA 5b5b mother and the HPA 5a5a homozygous neonate. The use of ART with gamete donation can increase the risk and the severity of alloimmune thrombocytopenia and must be considered in new and subsequent pregnancies.

Keywords: Alloimmune; Fetal; Neonatal; Thrombocytopenia.

Publication types

Case Reports

MeSH terms

Adult
Antigens, Human Platelet / metabolism*
Female
Humans
Infant, Newborn
Pregnancy
Thrombocytopenia, Neonatal Alloimmune / genetics*

Substances

5a alloantigen, human
Antigens, Human Platelet