Metabolic stroke in a late-onset form of isolated sulfite oxidase deficiency

We report the first case of late-onset isolated sulfite oxidase deficiency (ISOD) presenting with a stroke-like episode. Clinical, biochemical and neuroradiological features at diagnosis and during follow-up after dietary treatment intervention are described. Furthermore, pathogenic mechanisms possibly leading to stroke in ISOD are discussed.

► We present a case of isolated sulfite oxidase deficiency presenting with stroke.
► We describe favorable clinical and biochemical follow-ups after dietary intervention.
► Possible pathogenic mechanisms leading to stroke are described.
► Homocysteine revealed an important biomarker for early diagnosis.
► We underline the importance of enhanced knowledge of a rare but treatable disease.