Children Newly Diagnosed with Fetal and Neonatal Alloimmune Thrombocytopenia: Neurodevelopmental Outcome at School Age.

OBJECTIVE: To evaluate the neurodevelopmental outcome at school age in children newly diagnosed with fetal neonatal alloimmune thrombocytopenia (FNAIT).

STUDY DESIGN: This observational cohort study included children diagnosed with FNAIT between 2002 and 2014. Children were invited for cognitive and neurological testing. Behavioral questionnaires and school performance results were obtained. A composite outcome of neurodevelopmental impairment (NDI) was used, defined and subdivided into mild-to- moderate and severe NDI. Primary outcome was severe NDI, defined as IQ < 70, cerebral palsy with Gross Motor Functioning Classification Scale (GMFCS) level ≥ III, or severe visual/hearing impairment. Mild-to-moderate NDI was defined as IQ 70-85, minor neurological dysfunction or cerebral palsy GMFCS level ≤ II or mild visual/hearing impairment.

RESULTS: In total, 44 children were included at a median age of 12 years (range 6-17 years). Neuroimaging at diagnosis was available in 82% (36/44) of children. High-grade intracranial hemorrhage (ICH) was detected in 14% (5/36). Severe NDI was detected in 7% (3/44); two children had high-grade ICH and one low-grade ICH and perinatal asphyxia. Mild-to- moderate NDI was detected in 25% (11/44); one child had high-grade ICH and eight were without ICH, yet for two children neuroimaging was not performed. Adverse outcome (perinatal death or NDI) was 39% (19/49). Four children (9%) attended special needs education, three of whom had severe NDI and one with mild-to-moderate NDI. Total behavioral problems within the clinical range were reported in 12%, which is comparable with 10% in the general Dutch population.

CONCLUSION: Children who are newly diagnosed with FNAIT are at increased risk for long- term neurodevelopmental problems, even those without ICH.