Susac syndrome complicating a SARS-CoV-2 infection

Abstract

In 2020 the world was captivated by the COVID-19 pandemic. Current scientific evidence suggests an interaction of SARS-CoV-2 and the human immune system. Multiple cases were reported of patients with COVID-19 presenting with encephalopathy, confusion or agitation, stroke, and other neurologic symptoms. We present a case of a 40-year-old man diagnosed with Susac syndrome after COVID-19, presenting with acute sensorineural hearing loss, encephalopathy, a splenial "snowball-like" lesion, and branch retinal artery occlusions with distal arterial wall hyperintensity. Although the pathophysiology of Susac syndrome remains unclear, this case is in line with the ongoing debate about the influence of SARS-CoV-2 on the human immune system. Corticosteroid treatment was initiated, followed by two treatments with rituximab, with clinical improvement of the symptomatology. Maintenance treatment currently consists of mycophenolic acid (MPA). Future research will need to focus on the underlying mechanisms for COVID-19-associated (autoimmune) complications.

Keywords: COVID-19; Snowball-like lesion; Susac syndrome.

Fig. 1

Magnetic resonance imaging (MRI) after 7 days (diagnosis) with the characterizing splenial lesion of the corpus callosum on sagittal T2 localizer (A), DWI b1000 image (B), and T2 axial FLAIR (C), together with bilateral supratentorial enhancing white matter lesions, already present on the first MRI, on FLAIR (D), DWI b1000 (E), and ADC imaging (F)

Fig. 2

Fluorescein angiography within the first week and after 3 weeks visualized comparable BRAOs (arrowhead) in the superior and nasal area of the right eye, with AWH in the superior and inferior area. The left eye showed BRAOs in the superior, temporal and nasal area, with a superior zone of AWH in the first fluorescein angiography (white arrows) (A and B). A new angiography after 3 months showed residual BRAOs with even a deterioration of local arterial occlusions (C and D)

Fig. 3

Audiometry 1 month after the initial symptoms. Thresholds were 40dB at 500Hz, 50–60db at 1–4kHz, and 25dB at 8kHz in the right ear and 5dB at 250Hz, 5dB at 500Hz, 40dB at 1–2kHz, 60dB at 4kHz, and 50dB at 8kHz in the left ear. The initial audiometry was not interpretable.