clinical features

Last reviewed 03/2022

Cranial neuropathy is present in 60-70% of cases. One or more cranial nerves may be affected. Usually, there is facial palsy due to a lesion of the facial nerve. Less commonly, the VIII nerve is affected, the patient complaining of a sensorineural deafness. The oculomotor nerves, III, IV, and VI are infrequently affected, resulting in ocular motility disorders. Neuropathy of the other cranial nerves is rare.

Aseptic meningitis may be present in nearly one fifth of cases. There is an elevated CSF protein and reduced CSF glucose.

Hydrocephalus is the third most common complaint. This may result from granulomatous meningeal and juxta-ependymal involvement.

Infrequently, the hypothalamus is affected resulting in diabetes insipidus, hypersomnolence, and impaired temperature control.

Visual affects may be present due to bulbar or retrobulbar invasion of the optic nerve by granulomas; compression of the optic nerve by a granulomatous mass; or optic atrophy.

Epileptic seizures - minor, focal or generalised - may result from cerebral granulomatas.

Peripheral neuropathy may occur, either a chronic sensory neuropathy, or mononeuritis multiplex. Nerve damage may be caused by a granulomatous vasculitis, compressive effects, local effects of inflammation, or direct injury by the aetiological agent.

Rarely, acute or chronic myopathies may occur, but muscle biopsy reveals granulomas in about half of sarcoid patients even if the muscles is not clinically affected.