Early Predictors of Poor Neurologic Outcomes in a Prospective Cohort of Infants With Antenatal Exposure to Zika Virus.

BACKGROUND: Identify early predictors of poor neurodevelopment in infants with antenatal Zika virus (ZIKV) exposure. METHODS: Analysis of a prospective cohort of infants with antenatal ZIKV exposure confirmed by maternal or infant RT-PCR or IgM during the epidemic in Rio de Janeiro, Brazil. Clinical findings before 3 months of age were associated with Bayley-III Scales of Infant and Toddler Development conducted after 6 months of age. RESULTS: ZIKV exposure was confirmed in 219 cases; 162 infants were normocephalic, 53 were microcephalic, 4 had no head circumference recorded because of perinatal death/LTFU. Seven of the 112 normocephalic infants developed secondary microcephaly between 3 weeks and 8 months of age. Among the normocephalic at birth cohort, the mean HCZ among normal, at risk, and developmentally delayed children was significantly different (ANOVA, P = 0.02). In particular, the mean HCZ of the developmentally delayed group was significantly lower than that of the normal group (Tukey's test, P = 0.014). HCZ was more strongly associated with lower expressive language scores (P = 0.04) than receptive language scores (P = 0.06). The rate of auditory abnormalities differed among the normal, at risk, and developmentally delayed groups (Chi-squared test, P = 0.016), which was driven by the significant difference between the normal and at risk groups (post hoc test, P = 0.011, risk ratio 3.94). Auditory abnormalities were associated with both expressive and receptive language delays (P = 0.02 and P = 0.02, respectively). CONCLUSIONS: Clear predictors of neurodevelopment in normocephalic ZIKV-exposed children have not been previously identified. Our findings demonstrate that smaller HCZ and auditory abnormalities in these infants correlate with poor neurodevelopment as toddlers. Language delay is the most prominent developmental concern among these children, who will require frequent auditory and speech evaluations throughout childhood.

Association Between Antenatal Exposure to Zika Virus and Anatomical and Neurodevelopmental Abnormalities in Children.

Importance: Zika virus (ZIKV) is a mosquito-borne flavivirus recognized as teratogenic since the 2015 to 2016 epidemic. Antenatal ZIKV exposure causes brain anomalies, yet the full spectrum has not been delineated. Objective: To characterize the clinical features of ZIKV infection at a pediatric referral center in Rio de Janeiro, Brazil, among children with antenatal ZIKV exposure. Design, Setting, and Participants: Retrospective cohort study conducted from May to July 2019 of a prospective cohort of 296 infants with antenatal ZIKV exposure followed up since December 2015 at a tertiary maternity-pediatric hospital. Exposures: Zika virus infection during pregnancy. Main Outcomes and Measures: Characterization of clinical features with anthropometric, neurologic, cardiologic, ophthalmologic, audiometric, and neuroimaging evaluations in infancy and neurodevelopmental assessments (Bayley Scales of Infant and Toddler Development, Third Edition) from 6 to 42 months of age, stratified by head circumference at birth (head circumference within the reference range, or normocephaly [NC] vs microcephaly [MC]). Results: Antenatal exposure to ZIKV was confirmed for 219 of 296 children (74.0%) referred to Instituto Fernandes Figueira with suspected ZIKV infection through positive maternal or neonatal polymerase chain reaction analysis or IgM serology results. Of these children, 110 (50.2%) were boys, ages ranged from 0 to 4 years, and 53 (24.2%) had congenital microcephaly. The anomalies observed in ZIKV-exposed children with MC or NC were failure to thrive (MC: 38 of 53 [71.7%]; NC: 73 of 143 [51.0%]), cardiac malformations (MC: 19 of 46 [41.3%]; NC: 20 of 100 [20.0%]), excess nuchal skin (MC: 16 of 22 [72.7%]; NC: 35 of 93 [37.6%]), auditory abnormalities (MC: 13 of 50 [26.0%]; NC: 14 of 141 [9.9%]), and eye abnormalities (MC: 42 of 53 [79.2%]; NC: 28 of 158 [17.7%]). Although they experienced fewer neurologic abnormalities than children born with MC, those with NC also had frequent neurologic abnormalities (109 of 160 [68.1%]), including hyperreflexia (36 of 136 [26.5%]), abnormal tone (53 of 137 [38.7%]), congenital neuromotor signs (39 of 93 [41.9%]), feeding difficulties (15 of 143 [10.5%]), and abnormal brain imaging results (44 of 150 [29.3%]). Among 112 children with NC with Bayley-III evaluations, 72 (64.3%) had average or above-average scores; 30 (26.8%) scored 1 SD below average in at least 1 domain; and 10 (8.9%) scored 2 SD below average in at least 1 domain. Among 112 children with NC, a smaller head circumference at birth was significantly associated with subsequent below-average cognitive scores (U = 499.5; z = -2.833; P = .004) and language scores (U = 235.5; z = -2.491; P = .01). Conclusions and Relevance: Children without MC who were exposed to ZIKV in utero had a high frequency of anatomical and neurodevelopmental abnormalities. The head circumference at birth for children with NC was associated with neurocognitive development. Recognition of the wide spectrum of clinical phenotypes is critical to ensure early referral to rehabilitative interventions.

Screening Criteria for Ophthalmic Manifestations of Congenital Zika Virus Infection.

Importance: Current guidelines recommend screening eye examinations for infants with microcephaly or laboratory-confirmed Zika virus infection but not for all infants potentially exposed to Zika virus in utero. Objective: To evaluate eye findings in a cohort of infants whose mothers had polymerase chain reaction-confirmed Zika virus infection during pregnancy. Design, Setting, and Participants: In this descriptive case series performed from January 2 through October 30, 2016, infants were examined from birth to 1 year of age by a multidisciplinary medical team, including a pediatric ophthalmologist, from Fernandes Figueira Institute, a Ministry of Health referral center for high-risk pregnancies and infectious diseases in children in Rio de Janeiro, Brazil. Participants: Mother-infant pairs from Rio de Janeiro, Brazil, who presented with suspected Zika virus infection during pregnancy were referred to our institution and had serum, urine, amniotic fluid, or placenta samples tested by real-time polymerase chain reaction for Zika virus. Main Outcomes and Measures: Description of eye findings, presence of microcephaly or other central nervous system abnormalities, and timing of infection in infants with confirmed Zika virus during pregnancy. Eye abnormalities were correlated with central nervous system findings, microcephaly, and the timing of maternal infection. Results: Of the 112 with polymerase chain reaction-confirmed Zika virus infection in maternal specimens, 24 infants (21.4%) examined had eye abnormalities (median age at first eye examination, 31 days; range, 0-305 days). Ten infants (41.7%) with eye abnormalities did not have microcephaly, and 8 (33.3%) did not have any central nervous system findings. Fourteen infants with eye abnormalities (58.3%) were born to women infected in the first trimester, 8 (33.3%) in the second trimester, and 2 (8.3%) in the third trimester. Optic nerve and retinal abnormalities were the most frequent findings. Eye abnormalities were statistically associated with microcephaly (odds ratio [OR], 19.1; 95% CI, 6.0-61.0), other central nervous system abnormalities (OR, 4.3; 95% CI, 1.6-11.2), arthrogryposis (OR, 29.0; 95% CI, 3.3-255.8), and maternal trimester of infection (first trimester OR, 5.1; 95% CI, 1.9-13.2; second trimester OR, 0.5; 95% CI, 0.2-1.2; and third trimester OR, 0.3; 95% CI, 0.1-1.2). Conclusions and Relevance: Eye abnormalities may be the only initial finding in congenital Zika virus infection. All infants with potential maternal Zika virus exposure at any time during pregnancy should undergo screening eye examinations regardless of the presence or absence of central nervous system abnormalities.