Fetal–neonatal alloimmune thrombocytopenia: Mothers are affected too

Summary Fetal–neonatal alloimmune thrombocytopenia (FNAIT) results from parental platelet antigen incompatibility, with human platelet antigen (HPA)‐1a the most common. Human leukocyte antigen (HLA)‐DRB3*01:01 is strongly associated with the development of high titre anti‐HPA‐1a antibodies and B8DR3 with autoimmunity. Investigation of FNAIT has focused on fetal–neonatal haemorrhagic, placental and neurodevelopmental effects but has not included mothers. Symptomatic complaints pointing to autoimmunity from FNAIT‐affected mothers along with HLA overlap for FNAIT/autoimmunity (HLA‐DRB3*01:01, B8DR3) prompted exploration of autoimmune disorders. A de‐identified survey sent to NAITbabies mothers included medical review of systems with additional questions on autoimmunity. The frequency of autoimmunity in FNAIT mothers plus its fetal impact was explored. 125/232 (54%) of FNAIT mothers reported psychological problems >6 weeks, with 90% reporting ‘anxiety’ and >50% reporting each of stress, depression and sleep disturbances. Symptoms were more frequent in mothers whose child did not survive their intracranial hemorrhage (ICH) and those with multiple FNAIT‐affected children. The next most common medical symptoms were gastrointestinal and musculoskeletal with 30% frequency. Autoimmunity was mildly increased in mothers with FNAIT, for example, thyroiditis and three other B8DR3‐related diseases. Autoimmunity did not worsen neonatal ICH incidence or birthweight. By exploring affected mothers, this study expands the spectrum of diseases associated with FNAIT to include maternal autoimmunity and especially psychological symptoms.