Neurosarcoidosis: clinical experience and diagnostic pitfalls.

OBJECTIVE: To describe a group of patients with neurosarcoidosis and to highlight diagnostic difficulties based on current diagnostic criteria.

METHODS: The patient database of a general neurological department was searched for patients with established or suspected diagnosis of neurosarcoidosis. Twenty-four patients were identified with definite (n = 3), probable (n = 10) and possible neurosarcoidosis (n = 10). History and clinical, laboratory and imaging data of patients with definite and probable neurosarcoidosis were analyzed.

RESULTS: Cranial nerve symptoms were a dominant clinical feature, with the optic nerve being affected most frequently. Cerebrospinal fluid pleocytosis was found in more than half of the patients. Intrathecal IgG synthesis and oligoclonal bands were less frequent. There was a wide array of MRI lesions in both groups. Chest X-ray was false negative in 2 of 5 patients who also underwent a thoracic CT. Therapy with prednisolone was initiated in all patients. After a median of 36 months, 6 of 8 patients with follow-up data of >24 months were still in remission. Aggravation of symptoms required therapy escalation in 2 patients.

CONCLUSION: There is a wide range of clinical symptoms and test results in patients with "definite" or "probable" neurosarcoidosis. Because systemic involvement is a crucial diagnostic criterion, extensive medical work-up may be necessary. Prognosis under corticosteroid treatment may be better than previously thought.