Neurosarcoidosis without systemic sarcoidosis.

Neurosarcoidosis is a well-recognised complication of systemic sarcoidosis but diagnosis may be difficult if there is no clear evidence of an extracerebral manifestation of the disease. We present the case of a 42-year-old woman with clinical features characteristic of cerebral sarcoidosis including tetraparesis, diabetes insipidus, diencephalic hyperphagia, personality changes, and memory loss. Diagnosis was supported by cerebrospinal fluid (CSF) findings and magnetic resonance imaging (MRI): CSF showed mild lymphocytic pleocytosis, intrathecal production of IgG without oligoclonal bands, and a raised level of lysozyme. MRI revealed multiple contrast-enhanced granulomas at the base of the brain with partial involvement of diencephalic and mesencephalic structures and parts of the spinal cord. There was no evidence of systemic manifestation of sarcoidosis. Administration of corticosteroids led to improvement of the symptoms.