Incidental diagnosis and tempestive therapy in a case of neonatal alloimmune thrombocytopenia due to anti-HPA-5b

Neonatal alloimmune thrombocytopenia (NAIT) is usually attributable to HPA-1a antibodies. The authors report a case of incidentally diagnosed thrombocytopenia in a small for gestational age infant. A NAIT was suspected and she was successfully treated with intravenous IgG. The direct and indirect platelet suspension immunofluorescence test (PSIFT) in maternal blood suggested alloimmunization to HPA-5b. Empiric treatment with IgG could be useful in case of clear suspect even in absence of confirmed diagnosis.