Associated ultrasonographic findings in fetuses with microcephaly because of suspected Zika virus (ZIKV) infection during pregnancy

Abstract

OBJECTIVE: To describe fetal ultrasonographic findings and outcomes in a series of cases of fetal microcephaly associated with Zika virus infection. METHODS: Retrospective case series of microcephaly with definite (laboratory evidence) or highly probable (specific neuroimaging findings and negative laboratory results) maternal Zika virus infection. Microcephaly was graded as mild if the head circumference was between 2 and 3 standard deviation (SD) below the mean, and severe if 3 or more SD below the mean. Associated central nervous system (CNS) and extracranial malformations are described. RESULTS: Nineteen singleton pregnancies fulfilling the inclusion criteria were identified. Severe microcephaly and mild microcephaly were identified in 14 and 5 fetuses, respectively. Additional CNS malformations were present in 17 cases and 7 had extracranial congenital anomalies. Symptoms were reported in 13/19 cases at a gestational age between 5 and 16 weeks. Mean (±SD) gestational age at ultrasound diagnosis was 32.3 ± 5.1 weeks. Amniocentesis was performed in five cases at a median gestational age of 31 weeks (range 28-38) and was positive for Zika virus RT-PCR in two cases. There were three neonatal deaths and one stillbirth. CONCLUSION: In the presence of fetal microcephaly associated with Zika virus infection, CNS malformations are frequently detected.