Masqueraders of multiple evanescent white dot syndrome (MEWDS)

Purpose To describe disorders that can masquerade as multiple evanescent white dot syndrome (MEWDS). Design Retrospective, multicenter case series. Participants Patients who presented with clinical findings compatible with a diagnosis of MEWDS but were ultimately diagnosed with an alternative inflammatory, infectious, or neoplastic disorder. Methods Clinical records and multimodal imaging findings including fundus photography, fundus autofluorescence (FAF), fluorescein angiography (FA), indocyanine green angiography (ICGA), optical coherence tomography (OCT), and OCT angiography (OCTA) were analyzed. Main outcome measures Inclusion criteria to be defined as a masquerade syndrome for MEWDS included the presence of disseminated grayish-white outer retinal spots that were hyperautofluorescent on FAF and associated with ellipsoid zone (EZ) disruption on OCT. Results Twenty-two eyes of 13 patients were identified. All patients presented with the classic findings of MEWDS listed above. A MEWDS-like presentation was bilateral in nine of 13 patients (69%). Final diagnosis was determined on the basis of additional investigations including serologies and biopsy. These diagnoses included syphilis (three patients), lymphoma (three patients), idiopathic multifocal choroiditis (two patients), idiopathic retinal phlebitis (one patient), idiopathic acute zonal occult outer retinopathy (one patient), sarcoidosis (one patient), tuberculosis (one patient), and cancer-associated retinopathy (one patient). The outer retinal lesions and imaging findings resolved with treatment for the associated systemic disorders. Conclusions Widespread grayish-white outer retinal spots associated with hyperautofluorescence on FAF and disruption of the EZ on OCT are not pathognomonic for MEWDS. A high index of suspicion must be maintained for masqueraders of MEWDS, which can include serious inflammatory, infectious, and neoplastic disorders.