First Autopsy of a Newborn with Congenital Zika Syndrome in Puerto Rico.

We report on the first autopsy performed on a neonate with congenital Zika syndrome in Puerto Rico. A term male was born to a mother with confirmed Zika virus infection; he had a prenatal diagnosis of microcephaly and multiple cerebral calcifications, among other anomalies, and a normal male karyotype (determined by amniocentesis). He required neonatal resuscitation at birth and died at 2 days ofage. At autopsy, his head circumference was only 1.5 standard deviations below the mean, not fulfilling the criteria for microcephaly. He presented scissor legs, clenched and hyperflexed hands, and multiple contractures (arthrogryposis). The central nervous system findings were consistent with Zika encephalopathy: ventriculomegaly, lissencephaly, and severe encephalic degeneration with numerous dystrophic calcifications, among other findings. These anomalies were most likely secondary to congenital ZV infection. Although prenatally diagnosed with microcephaly, he did not fulfill the criteria after birth, which fact indicates the need for reassessment of the definition of microcephaly as it applies to patients exposed prenatally to the ZV.