The value of [18F]-fluorodeoxyglucose-positron emission tomography/CT scanning in the diagnosis of neurosarcoidosis.

Sarcoidosis is a granulomatous disease of unknown aetiology which primarily affects the lungs, but can affect other tissues including the central nervous system (CNS). In neurosarcoidodis, the CNS is often the only affected site, which makes a tissue diagnosis difficult. Although a clinical diagnosis of neurosarcoidosis can often be made, the wide range of potential differential diagnoses, including other steroid responsive conditions (such as idiopathic lymphocytic meningitis) means that a confirmed diagnosis is invaluable. This is particularly important because neurosarcoidosis has a poor prognosis and aggressive immunosuppressive treatment is generally recommended. We present a man with clinically suspected neurosarcoidosis where attempts to obtain histological confirmation of the disease through skin and meningeal biopsy was unhelpful, but a lymph node biopsy, directed with the use of [18F]-fluorodeoxyglucose-positron emission tomography/CT scanning was diagnostic.