Overlapping Spectrum of Retinochoroidal Scarring in Congenital Zika Virus and Toxoplasmosis Infections

Abstract

Background and objective: Antenatal Zika virus (ZIKV) or toxoplasmosis infections may present with isolated eye abnormalities with absence of other apparent birth defects. The purpose of this article is to discuss the overlapping spectrum of clinical presentation and retinochoroidal scarring in congenital ZIKV and toxoplasmosis infections.

Patients and methods: Prenatal ultrasound abnormalities seen from antenatal ZIKV and toxoplasmosis infections overlap and may include intracranial calcifications, microcephaly, and intrauterine growth restriction. The clinical spectrum of both infections in less severely affected infants and children may include nonspecific neurological impairment such as developmental delay and seizures.

Results: Inherent limitations in serological testing pose additional barriers in establishing a diagnosis. Retinal pigment epithelium (RPE) mottling in ZIKV infection can occur in isolation or adjacent to retinochoroidal atrophy. In contrast, RPE mottling outside of the borders of retinochoroidal atrophy is not typically seen in toxoplasmosis. To date, postnatal reactivation of congenital eye lesions as seen in toxoplasmosis have not been reported with ZIKV infection.

Conclusions: As children infected with congenital ZIKV grow older, subclinical eye abnormalities may be indistinguishable from toxoplasmosis. Brazil has had high prevalence of both diseases with long-term information available on toxoplasmosis only. Surveillance guidelines for asymptomatic eye abnormalities will likely evolve. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:779-784.].

Figure 1.

Spectrum of retinal lesions associated with Zika virus (ZIKV) infection. All mother-infant pairs tested polymerase chain reaction-positive for ZIKV and negative for toxoplasmosis immunoglobulin G (IgG)/IgM. (A) Retinal pigment epithelium (RPE) mottling in the macula. (B) RPE mottling with superficial atrophy in the macula. (C) Deep chorioretinal atrophy with RPE hyperpigmentation outside of the lesion. (D) RPE mottling and large areas of chorioretinal atrophy.

Figure 2.

Typical retinochoroidal lesions seen in toxoplasmosis. (A) Extra-macular lesion with pigmented and fibrotic retinochoroidal scar. (B) Active lesion with vitritis causing “fog in headlight” appearance.