Brain Imaging of Children with Congenital Zika Virus Infection

An outbreak of Zika virus in Brazil in 2015 was accompanied by an outbreak of congenital microcephaly, which is now known to be a frequent sign of congenital Zika virus infection. The clinical course of affected infants is unknown. The main findings on brain computed tomography (CT) of affected newborns are cerebral calcifications, mainly at the cortical–white matter junction, and decreased brain volume along with malformation of cortical development. Follow-up studies of affected infants have not previously been reported. Now, investigators report on 37 children with probable or proven Zika infection. Initial scans were performed at local hospitals using different equipment and protocols. Follow-up CTs at a median of 415 days of age were performed at a single center.

Thirty-five of the infants (95%) had microcephaly at birth and 2 children without microcephaly at birth developed microcephaly later. Congenital Zika syndrome was confirmed in in 29 of the children. The rest did not have serologic confirmation. Initial CT studies showed punctate brain calcifications in all 37. The most common location was at the cortical–white matter junction (in 95% of the children). At follow-up, calcifications had diminished in number, size, or density in 34 children, were no longer present in 1 child, and were unchanged in 2 children. Calcifications were no longer visible at the cortical–white matter junction of all lobes in one, at the thalamus in two, at the brainstem in in two, and in the periventricular area in three. None had an increase in the calcifications. Diminution in calcifications did not correlate with clinical improvement.