Dataset Information

Quantitative Assessment of Microstructural Changes of the Retina in Infants With Congenital Zika Syndrome.

ABSTRACT:

Importance

A better pathophysiologic understanding of the neurodevelopmental abnormalities observed in neonates exposed in utero to Zika virus (ZIKV) is needed to develop treatments. The retina as an extension of the diencephalon accessible to in vivo microcopy with spectral-domain optical coherence tomography (SD-OCT) can provide an insight into the pathophysiology of congenital Zika syndrome (CZS).

Objective

To quantify the microstructural changes of the retina in CZS and compare these changes with those of cobalamin C (cblC) deficiency, a disease with potential retinal maldevelopment.

Design, setting, and participants

This case series included 8 infants with CZS and 8 individuals with cblC deficiency. All patients underwent ophthalmologic evaluation at 2 university teaching hospitals and SD-OCT imaging in at least 1 eye. Patients with cblC deficiency were homozygous or compound heterozygotes for mutations in the methylmalonic aciduria and homocystinuria type C (MMACHC) gene. Data were collected from January 1 to March 17, 2016, for patients with CZS and from May 4, 2015, to April 23, 2016, for patients with cblC deficiency.

Main outcomes and measures

The SD-OCT cross-sections were segmented using automatic segmentation algorithms embedded in the SD-OCT systems. Each retinal layer thickness was measured at critical eccentricities using the position of the signal peaks and troughs on longitudinal reflectivity profiles.

Results

Eight infants with CZS (5 girls and 3 boys; age range, 3-5 months) and 8 patients with cblC deficiency (3 girls and 5 boys; age range, 4 months to 15 years) were included in the analysis. All 8 patients with CZS had foveal abnormalities in the analyzed eyes (8 eyes), including discontinuities of the ellipsoid zone, thinning of the central retina with increased backscatter, and severe structural disorganization, with 3 eyes showing macular pseudocolobomas. Pericentral retina with normal lamination showed a thinned (<30% of normal thickness) ganglion cell layer (GCL) that colocalized in 7 of 8 eyes with a normal photoreceptor layer. The inner nuclear layer was normal or had borderline thinning. The central retinal degeneration was similar to that of cblC deficiency.

Conclusions and relevance

Congenital Zika syndrome showed a central retinal degeneration with severe GCL loss, borderline inner nuclear layer thinning, and less prominent photoreceptor loss. The findings provide the first, to date, in vivo evidence in humans for possible retinal maldevelopment with a predilection for retinal GCL loss in CZS, consistent with a murine model of the disease and suggestive of in utero depletion of this neuronal population as a consequence of Zika virus infection.

SUBMITTER: Aleman TS

PROVIDER: S-EPMC5710497 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundChildren with in utero Zika virus (ZIKV) exposure without congenital Zika syndrome (CZS) are at risk for abnormal neurodevelopment. Preschool-age outcomes for children with antenatal ZIKV exposure have not yet been established.MethodsChildren with in utero ZIKV exposure and non-exposed controls had neurodevelopmental evaluations at age 3-5 years in Sabanalarga, Colombia. Cases did not have CZS and were previously evaluated prenatally through age 18 months. Controls were born before ZIKV arrival to Colombia. Neurodevelopmental assessments included Pediatric Evaluation of Disability Inventory (PEDI-CAT), Behavior Rating Inventory of Executive Function (BRIEF-P), Bracken School Readiness Assessment (BSRA), and Movement Assessment Battery for Children (MABC). Family demographics and child medical history were recorded.ResultsFifty-five ZIKV-exposed children were evaluated at mean age 3.6 years and 70 controls were evaluated at 5.2 years. Family demographics were similar between groups. BRIEF-P t-scores were higher for cases than controls in shift and flexibility domains. Cases had lower PEDI-CAT mobility t-scores compared to controls. There was no difference in MABC between groups. In 11% of cases and 1% of controls, parents reported child mood problems.ConclusionsChildren with in utero ZIKV exposure without CZS may demonstrate emerging differences in executive function, mood, and adaptive mobility that require continued evaluation.ImpactPreschool neurodevelopmental outcome in children with in utero Zika virus exposure is not yet known, since the Zika virus epidemic occurred in 2015-2017 and these children are only now entering school age. This study finds that Colombian children with in utero Zika virus exposure without congenital Zika syndrome are overall developing well but may have emerging differences in executive function, behavior and mood, and adaptive mobility compared to children without in utero Zika virus exposure. Children with in utero Zika virus exposure require continued multi-domain longitudinal neurodevelopmental evaluation through school age.

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