Clinical features and diagnosis of neurosarcoidosis - review article.

Neurosarcoidosis affects 5-26% of patients with systemic sarcoidosis and can be the first or only manifestation of the disease. Neurosarcoidosis can affect any part of the nervous system with heterogeneous clinical manifestations and imaging appearances that overlap with many infectious, inflammatory, and neoplastic disorders, making its diagnosis challenging. In the absence of a reliable biomarker to confirm neurosarcoidosis, the diagnosis is based on identifying a compatible clinical and imaging profile and identifying pathological evidence of non-caseating granulomas by biopsy of other organs or, if needed, in the nervous system, with the exclusion of other causes of granulomatous disease and possible neuroinfectious and neuroinflammatory disorder mimics. This review focuses on the clinical features of neurosarcoidosis with an emphasis on the recognition of the main presentation phenotypes and the initial diagnostic approach and differential diagnosis of neurosarcoidosis.