Ocular Findings in Infants With Presumed Zika Virus Infection
The Zika virus has quickly reached epidemic proportions, especially in northeastern Brazil, and it has rapidly spread to other parts of the Americas. A recent increase in the prevalence of microcephaly in newborn infants and vision-threatening findings in these infants is likely associated with the rapid spread of the virus. As such, de Paula Freitas et al. evaluated the ocular findings in infants with microcephaly associated with presumed intrauterine Zika virus infection in the state of Bahia, Brazil.
This case series was conducted at the Roberto Santos General Hospital, a tertiary hospital in Salvador, Brazil. Twenty-nine infants (58 eyes) with microcephaly (defined by a cephalic circumference of ≤32 cm) and a presumed diagnosis of congenital Zika virus were recruited through an active search and referrals from other hospitals and health institutions.
The study was conducted between Dec. 1 and Dec. 21, 2015. All of the infants and their mothers underwent systemic and ophthalmic examinations. Anterior segment and retinal, choroidal, and optic nerve abnormalities were documented using a wide-field digital imaging system. The differential diagnosis included cytomegalovirus, herpes simplex virus, human immunodeficiency virus, rubella, syphilis, and toxoplasmosis, which were ruled out through serologic and clinical examinations.
Results showed that 23 of the 29 mothers (79.3%) reported suspected Zika virus infection signs and symptoms during pregnancy—18 in the first trimester, 4 in the second trimester, and 1 in the third trimester. Ocular abnormalities were present in 17 eyes (29.3%) of 10 children (34.5%). Bilateral findings were observed in 7 of 10 infants presenting with ocular lesions, the most common of which were focal pigment mottling of the retina and chorioretinal atrophy in 11 of the 17 eyes with abnormalities (64.7%), followed by optic nerve abnormalities in 8 eyes (47.1%), bilateral iris coloboma in 1 patient (2 eyes [11.8%]), and lens subluxation in 1 eye (5.9%).
The authors concluded that congenital infection due to presumed Zika virus exposure is associated with vision-threatening findings, which include bilateral macular and perimacular lesions as well as optic nerve abnormalities in most cases.
Outdoor Ozone Air Pollution and Dry Eye Disease in South Korea
The ocular surface is continuously exposed to pollutants in outdoor air, and ocular surface abnormalities related to air pollution are thought to be a subtype of dry eye disease (DED). In the first large-scale study to evaluate the association between various outdoor air pollutants and DED, Hwang et al. found that higher ozone levels and lower humidity levels were associated with DED in a Korean population.
For this population-based crosssectional study, the researchers used data from the fifth Korea National Health and Nutrition Examination Survey, which was conducted from Jan. 1, 2010, to Dec. 31, 2012. Outdoor air pollution measurements—mean annual humidity, particulate matter with aerodynamic diameter less than 10 μm (PM10), ozone, and nitrogen dioxide levels—were collected from 283 national monitoring stations in South Korea.
Among 16,824 participants (7,104 men and 9,720 women), higher ozone levels and lower humidity levels were associated with symptoms and diagnosis of DED. In one analytic model, the researchers found that an increase in ozone levels of 0.003 parts per million (ppm) was significantly associated with symptoms and diagnosis of DED, while a 5% increase in humidity levels was associated with decreased symptoms and diagnosis of DED. In a second analytic model, an increase in nitrogen dioxide of 0.003 ppm was also associated with a diagnosis of DED. Levels of sulfur dioxide and PM10 were not associated with symptoms or diagnoses of DED in either model.
The authors noted that their findings on ozone, humidity, and DED demonstrate associations, not definitive cause and effect.
JAMA Ophthalmology summaries are based on authors’ abstracts, as edited by senior editor(s).
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