Early Clinical Infancy Outcomes for Microcephaly and/or Small for Gestational Age Zika-Exposed Infants.

BACKGROUND: Zika-exposed infants with microcephaly (proportional or disproportional) and those who are small for gestational age without microcephaly should be closely followed, particularly their growth trajectories. They are at high risk of adverse outcomes in the first year of life.Antenatal Zika virus (ZIKV) exposure may lead to adverse infant outcomes including microcephaly and being small for gestational age (SGA). ZIKV-exposed infants with a diagnosis of microcephaly (proportional [PM] or disproportional [DM]) or SGA at birth were evaluated with anthropometric measurements and health outcomes. METHODS: Infants had laboratory-confirmed ZIKV exposure in Brazil. PM, DM, or SGA classification was based on head circumference and weight. First-year growth parameters and clinical outcomes were recorded with analyses performed. RESULTS: Among the 156 ZIKV-exposed infants, 14 (9.0%) were SGA, 13 (8.3%) PM, 13 (8.3%) DM, and 116 (74.4%) were neither SGA nor had microcephaly (NSNM). High rates of any neurologic, ophthalmologic, and hearing abnormalities were observed for PM (100%), DM (100%), and SGA (42.9%) vs NSNM infants (18.3%; P <.001); odds ratio [OR], 3.4 (95% confidence interval [CI], 1.1-10.7) for SGA vs NSNM. Neuroimaging abnormalities were seen in 100% of PM and DM and in 42.9% of SGA vs NSNM infants 16%; (P <.001); OR 3.9 (95% CI, 1.2-12.8) for SGA vs NSNM. Growth rates by z score, particularly for microcephaly infants, were poor after birth but showed improvement beyond 4 months of life. CONCLUSIONS: ZIKV-exposed infants with microcephaly (PM and DM) had similarly high rates of adverse outcomes but showed improvement in growth measurements beyond 4 months of life. While SGA infants had fewer adverse outcomes compared with microcephaly infants, notable adverse outcomes were observed in some; their odds of having adverse outcomes were 3 to 4 times greater compared to NSNM infants.Zika-exposed infants with microcephaly, irrespective of being proportional or disproportional, and those who are small for gestational age without microcephaly should be closely followed, particularly their growth trajectories. They are at high risk of adverse outcomes in the first year of life.

Association Between Neonatal Neuroimaging and Clinical Outcomes in Zika-Exposed Infants From Rio de Janeiro, Brazil.

Importance: Congenital Zika virus (ZIKV) infection may present with a spectrum of clinical and neuroradiographic findings. Objective: To determine whether neuroimaging findings for infants with a history of ZIKV exposure are associated with infant clinical outcomes and gestational age at antenatal ZIKV infection. Design, Setting, and Participants: This cohort study retrospectively reviewed neuroimaging results (computed tomography and/or magnetic resonance imaging scans) of 110 ZIKV-exposed infants from a maternity and children's hospital in Rio de Janeiro, Brazil, following the 2015 to 2016 ZIKV epidemic. Neuroimaging from March 1, 2016, to June 30, 2017, was evaluated to determine whether findings were associated with clinical outcomes and the timing of maternal ZIKV infection. Data were analyzed from July 1, 2017, to August 30, 2018. Exposures: Neuroimaging (computed tomography and/or magnetic resonance imaging) was performed on ZIKV-exposed infants after birth. Blood and/or urine specimens from mothers and infants were tested for ZIKV by polymerase chain reaction assay. Main Outcomes and Measures: Neuroimaging studies were evaluated for structural abnormalities and other forms of brain injury. Results: A total of 110 infants with a mean (SD) gestational age of 38.4 (2.1) weeks had neuroimaging and clinical outcome data reviewed. Of these, 71 (65%) had abnormal neuroimaging findings, with the majority (96%) classified as having severe ZIKV infection at birth. The most common neuroimaging abnormalities were structural abnormalities including brain calcifications, especially at the cortico-subcortical white matter junction, cortex malformations, ventriculomegaly, and reduced brain volumes, followed by brainstem hypoplasia, cerebellar hypoplasia, and corpus callosum abnormalities. Frequency of abnormal imaging was higher in infants with specific clinical findings as opposed to those without them; these findings included fetal brain disruption sequence (100% vs 35%), microcephaly (100% vs 30%), congenital contractures (100% vs 58%), ophthalmologic abnormalities (95% vs 44%), hearing abnormalities (100% vs 58%), and neurologic symptoms (94% vs 10%). Four of 39 infants (10%) without initial evidence of severe ZIKV infection and normal findings on neurologic evaluation at birth had abnormal neuroimaging findings. Neuroimaging abnormalities differed by trimester of maternal ZIKV infection, with 63% of infants born to mothers infected in the first trimester, 13% of infants born to mothers infected in the second trimester, and 1% of infants born to mothers infected in the third trimester exhibiting neuroimaging abnormalities. The odds of abnormal neuroimaging were 7.9 times greater for infants with first trimester ZIKV exposure compared with other trimesters combined (odds ratio, 7.9; 95% CI, 3.0-20.4; P < .001). Conclusions and Relevance: Neuroimaging abnormalities of computed tomography and/or magnetic resonance imaging scans were common in ZIKV-exposed infants. While neuroimaging abnormalities were seen in 10% of infants without clinically severe ZIKV, most occurred almost exclusively among those with clinically severe ZIKV, especially among those with a history of ZIKV exposure in the first trimester.