Acute unilateral maculopathy associated with adult onset of hand, foot and mouth disease: a case report

BACKGROUND: To report the case of a 31-year-old patient with Hand, Foot and Mouth Disease (HFMD) and concurrent acute monocular maculopathy, and to describe multimodal imaging findings never before described including optical coherence tomography angiography (OCT-A). CASE PRESENTATION: Nine days after the onset of clinically highly probable but not laboratory-verified HFMD, a 31-year old male noticed a central scotoma, distorted lines and loss of visual acuity (Snellen visual acuity 20/400) in his right eye. Funduscopy revealed focal alterations in the retinal pigmented epithelium (RPE) and yellow retinal dots corresponding to focal dots of decreased fundus autofluorescence (FAF) surrounded by increased FAF. Spectral domain optical coherence tomography (SD-OCT) demonstrated irregularities in the ellipsoide zone, hyperreflective dots above the RPE and RPE thickening. Fundus fluorescein angiography (FAG) revealed central hypofluorescence in the macular area in the early phase, as well as increasing focal hyperfluorescence in the late phase corresponding with RPE defects observed in FAF. Indocyanine green angiography (ICGA) showed central hypofluorescence in the early and late phase, corresponding with areas of reduced flow in the choroidea and choriocapillaris as apparent in OCT-A. Visual acuity improved within 3 months without any systemic or local therapy. At his three-month follow-up, SD-OCT revealed subtle subretinal fluid that resolved spontaneously over time. No signs of choroidal neovascularization were observed. Twelve months following the onset of symptoms Snellen visual acuity was 400/400. Multimodal imaging revealed subtly changed, decreased FAF while the choroidal architecture recovered completely as demonstrated by OCT-A. CONCLUSIONS: HFMD-associated maculopahty is an uncommon but important differential diagnosis of chorioretinitis with macular involvement. The prognosis can be good and the initially observed morphological pathologies such as impaired perfusion of the choroidal vessels can recover spontaneously over a period lasting 12 months. OCT-A can be employed as a non-invasive tool to detect the reduced perfusion of the choroidal vessels and for monitoring the disease course.