Zika: neurological and ocular findings in infant without microcephaly

Abstract

The emergence of Zika virus (ZIKV) in Brazil coincided with increased reports of newborn babies with microcephaly, congenital malformations, and neurological syndromes. 1 In February, 2016, WHO declared ZIKV and microcephaly a Public Health Emergency of International Concern because of the rapid spread of ZIKV infection. In January, 2016, we reported ocular fi ndings in infants with microcephaly and presumed congenital Zika virus infection in Pernambuco, Brazil. Similar ocular findings have been reported in infants assessed in Bahia, Brazil. These reports followed establishment of microcephaly (head circumference two SDs below the mean for age and sex) as an inclusion criterion for the screening of babies for congenital Zika virus infection. Therefore, the presence or absence of microcephaly was used as a cutoff for screening, and only cases that fulfi lled this criterion were classifi ed as presumed cases of congenital Zika virus infection and further investigated. To the best of our knowledge, no reports exist on infants with diagnosis of congenital Zika virus infection, who did not have microcephaly, but did have ocular fi ndings. Here we report the ophthalmic findings of an infant (age at exam: 57 days; head circumference: 33 cm; weight at birth: 3500 g; gestational age at birth: 38 weeks) who was referred for ophthalmic examination by a neurologist for suspected congenital Zika virus infection. The mother reported that she did not have ZIKV-related symptoms, use illicit drugs, drink alcohol, or smoke during pregnancy. The infant presented lower limb and upper limb spasms at birth. CT scans detected cerebral calcifi cations in the basal ganglia, ventriculomegaly, and lissencephaly. Ocular examination included anterior segment biomicroscopy and fundus evaluation. A chorioretinal scar was detected on the macular region of the left eye (fi gure), similar to scars previously reported in congenital Zika virus infection. Toxoplasmosis, rubella, cytomegalovirus, herpes simplex, HIV, and dengue fever virus were ruled out in both mother and infant. IgM antibody capture (MAC)-ELISA for ZIKV was done in the cerebral spinal fl uid of the infant, which was positive, confirming our hypothesis of congenital Zika virus infection. This case highlights that microcephaly should not be a required criterion for congenital Zika virus infection diagnosis, since infants without microcephaly could still have been infected by ZIKV during gestation. We emphasise the need for public health authorities to provide fundus screening to infants with suspected congenital Zika virus infection, because ocular findings might be underdiagnosed if microcephaly continues to be an inclusion criterion in the screening of this group of infants. We declare no competing interests.