ABSTRACT
PURPOSE: To report our experience with a case of a very atypical clinical onset of multiple sclerosis in a young boy during a COVID-19 infection. CASE REPORT: A 16-year-old boy was referred to our ophthalmology clinic with a complete isolated bilateral horizontal gaze palsy. The condition had onset suddenly 2 weeks prior and he had no associated symptoms, as well as no significant medical history. His corrected visual acuity was 0.0 logMAR in both eyes. While hospitalized, he was found infected with COVID-19. Subsequent brain MRI showed multiple lesions typical of a yet undiagnosed MS, as well as an active pontine plaque which was highly probable the cause of the horizontal gaze palsy. High-dose steroid treatment was initiated 1 week later, after the patient exhibited negative COVID-19 test results. CONCLUSION: Clinical manifestations of MS are rarely seen in male teenagers and only a few cases of isolated bilateral horizontal gaze palsy have been reported as the initial manifestation, but never during concomitant COVID-19 infection. We presume that the presence of COVID-19 may have been a neuroinflammatory trigger of underlying MS.