Rasmussen encephalitis and comorbid autoimmune diseases: A window into disease mechanism?

OBJECTIVE: To describe a potential association between comorbid autoimmune disease and Rasmussen encephalitis (RE) and discuss potential insights into underlying RE pathogenesis.

METHODS: We report a case series of 4 patients with RE in whom a comorbid autoimmune disease was subsequently diagnosed and review the literature on possible common susceptibility factors.

RESULTS: In 4 patients who presented with typical clinical features of RE, a comorbid autoimmune disease was subsequently diagnosed: Hashimoto thyroiditis, ulcerative colitis, Crohn disease, and systemic lupus erythematosus. We discuss the possible common predisposing factors.

CONCLUSIONS: The association of RE, a rare entity, with a comorbid autoimmune disease raises the possibility of shared mechanisms of susceptibility, including common immunogenetic and/or environmental risk factors.