We present a case of a 40-year-old female patient who was admitted to the Eye Clinic, Clinical Center of Montenegro (Podgorica, Montenegro) in April 2021. The patient's main complaint was vision impairment in the left eye, which occurred 14 days after a positive polymerase chain reaction (PCR) test result for SARS-CoV-2 infection. Vision impairment occurred suddenly, four days prior to admission. The only COVID-19 symptoms preceding the vision impairment were an irritating cough and severe headache. These symptoms started a day prior to the diagnosis of COVID-19 and lasted until changes in visual acuity occurred. The patient had hypertension controlled by ramipril (Zdravlje AD, Leskovac, Serbia) with no signs of complications in the kidneys, eyes, or cardiovascular system. In addition, she was diagnosed with Hashimoto thyroiditis 10 years prior to admission, which was successfully treated with levothyroxine (Merck KGaA, Darmstadt, Germany).
A complete eye examination was performed, followed by optical coherence tomography (OCT), fundus photography (FP), fundus autofluorescence (FAF), and fluorescein angiography (FA) tests. Best corrected visual acuity in the left and right eyes was 0.1 and 1.0, respectively. The affected eye showed a mild relative afferent pupillary defect (RAPD). Biomicroscopic examination showed normal findings. The anterior chamber was transparent with a normal iridocorneal angle. Intraocular pressure was within the normal range. Fundoscopic examination of the right eye was normal, but the fundus of the left eye showed several white dots located around the optic disc and scattered throughout the posterior pole of the retina. The fovea was yellowish with granularity (figure 1). FAF test showed hypofluorescent spots and dots throughout the posterior pole of the retina. The OCT examination of the right eye showed a normal configuration of the macula, but the left eye showed pathological findings - appearing as a multifocal nodular thickening in deep layers of the retina as well as areas of disruption of the ellipsoid zone (EZ) throughout the posterior pole (figure 2). FA test showed early punctate hyperfluorescence in a rim-like pattern and late staining in areas corresponding to the white dots (figure 3). 
Following an initial diagnosis of multiple evanescent white dot syndrome (MEWDS), we requested additional tests to determine the cause of these abnormalities to provide optimal treatment. Complete blood count (CBC), erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), fibrinogen, blood glucose, urea, creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lipid panel, and urine analyses were all within normal range. Serum immunoglobulin levels as well as complement components C3 and C4 were also within normal range. Rheumatologic tests for antinuclear antibodies (ANAs), anti-Ro antibodies, antineutrophil cytoplasmic antibodies (ANCA), rheumatoid factor (RF), cyclic citrullinated peptide (CCP) antibodies, anti-smooth muscle antibodies (ASMA), anticardiolipin antibodies, and anti-beta 2 glycoproteins 1 and 2 were all negative. Tests for herpes simplex virus type 1 and 2 (HSV1 and HSV2), herpes zoster virus (HZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), Borrelia burgdorferi, Treponema pallidum, and Toxoplasma gondii were also negative. The QuantiFERON-TB Gold (QFT) test was false-positive. To rule out tuberculosis, we performed a purified protein derivative (PPD) skin test, which was negative. To exclude pneumonia and related complications, multi-slice computed tomography (MSCT) of the chest was performed, which was normal.
The patient was prescribed nepafenac solution 1 mg/mL (Alcon pharmaceuticals Ltd, Belgrade, Serbia) and acetazolamide (Remedica Ltd, Limassol, Cyprus) to reduce inflammation and edema. After one week of treatment, a follow-up examination showed a decrease in edema and improvement in the corrected visual acuity in the left eye (0.8). A fundus examination of the left eye showed complete resorption of the chorioretinal infiltration. An OCT examination of the eye showed thickening of the choroid, subtle discontinuity of the photoreceptor layer, and scarring of the retinal pigment epithelium.
Written informed consent was obtained from the patient for the publication of this case report.