Demyelination due to sarcoidosis

Definition

Diagnosis of neurosarcoidosis is most challenging when there is no evidence for disease outside the nervous system. The diagnosis of neurosarcoidosis requires a compatible clinical or radiological picture of sarcoidosis and histological confirmation of noncaesating granulomas. Criteria for the diagnosis of neurosarcoidosis : Definite: Clinical presentation compatible with neurosarcoidosis Exclusion of other possible causes Positive nervous system histology Probable: Clinical presentation compatible with neurosarcoidosis Laboratory support of CNS inflammation (high concentrations of CSF protein and high numbers of cells, the presence of oligoclonal bands, or MRI evidence compatible with neurosarcoidosis). Exclusion of other possible causes Evidence of systemic sarcoidosis (Positive histology or at least two indirect indicators from gallium scan, chest imaging, and serum angiotensin-converting-enzyme). Possible:Clinical presentation compatible with neurosarcoidosis Exclusion of other possible causes. Neuroimaging studies, especially MRI, are the most sensitive diagnostic tools for the detection and localisation of neurological lesions. However, they are not specific as their appearences on radiography are highly variabale. MRI may show parenchymatous mass lesions-hyperintense lesions on T2 seuences, with linear enhancement of thickened meninges and focal nodular enhancement.

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