Successful treatment of a complete Susac syndrome in a 16-year-old boy: A case report.

Key Clinical Message: We reported a pediatric case of SuS with a complete diagnosis triad. Although the optimal treatment of SS is unclear, prompt diagnosis and treatment can result in almost a complete recovery.

Abstract: Susac's syndrome (SuS) is a rare, autoimmune disorder known as a typical triad of sensorineural hearing impairment, central nervous system involvement, and multiple branch retinal artery occlusions (BRAOs). It is usually misdiagnosed or underdiagnosed because its symptoms may vary at the presentation time. Diagnosis can be established based on neuroimaging, ophthalmic examination, and audiometry, which match the clinical symptoms. SuS is very limited and rare in childhood and can be easily misdiagnosed with multiple sclerosis or acute disseminated encephalomyelitis. We report a 16-year-old boy patient with a completed SuS triad including BRAO in fluorescent angiography (FA), mild to moderate sensory neural hearing loss (SNHL), "Snowball lesions," and "pearl of string" signs in magnetic resonance imaging (MRI). Successful treatment was achieved with methylprednisolone, rituximab, azathioprine, cyclophosphamide, and plasmapheresis. SuS is a rare disorder, which rarely presents with a full triad and all the manifestations may not be present at the onset of the disease, leading to misdiagnosis or underdiagnosis. Our case is exceptional because he was in a pediatric age and presented with a complete triad of SuS which adds to the rarity of this disease. Although optimal treatment of SuS is unclear, our treatment regimen resulted in almost a complete recovery.