Multiple Evanescent White Dot Syndrome (MEWDS) Secondary to Acute Retinal Pigment Epitheliitis: Possible Atypical Presentation of MEWDS?

Purpose: To report a case of possible multiple evanescent white dot syndrome secondary (MEWDS) to acute retinal pigment epitheliitis (ARPE).

Methods: Case report.

Results: A 16-year-old female presented to the ophthalmology emergency department with a 5-day history of blurred vision in the left eye (OS). Initial examination revealed a visual acuity (VA) of 89 letters on the Early Treatment Diabetic Retinopathy Study (ETDRS)(-0.08 logMAR) chart in the right eye (OD) and 53 letters(0.64 logMAR) in the OS. Anterior segment biomicroscopy was normal, with no evidence of inflammation in the anterior chamber. Evaluation of the posterior pole revealed an alteration in the retinal pigment epithelium (RPE) in the OS. Optical coherence tomography (OCT) at the macular level showed disruption at the external limiting membrane (ELM), ellipsoid zone (EZ), interdigitation zone (IZ), and the RPE-Bruch's membrane (RPE-Bm) complex. Fundus autofluorescence (FAF) demonstrated hypofluorescent areas in the peripapillary region. No treatment was indicated. After two weeks, there was an improvement in VA, with 90 ETDRS letters(-0.1 logMAR) in the OD and 85 letters(0.0 logMAR) in the OS, as well as improvement in the OCT at the level of the ELM and EZ. However, a marked increase in white spots was observed throughout the posterior pole. By 5-months post-onset, a complete resolution of retinal alterations was observed in both OCT and FAF.

Conclusion: ARPE and MEWDS exhibit overlapping clinical features, which can sometimes complicate differentiation. This case is consistent with MEWDS secondary to ARPE, although an atypical presentation of MEWDS cannot be ruled out.