Isolated common peroneal nerve palsy in sarcoidosis.

Sarcoidosis is a multisystem granulomatous disorder of unknown aetiology, characterized pathologically by the presence of noncaseating epithelioid granulomas. Estimated prevalence of sarcoidosis is 10-20 per 100,000 populations, 3-4 times more common in blacks, presents between the ages of 10-40 years in (70-90)% of cases. Sarcoid neuropathy is one of the rare conditions. It involves approximately 5% of sarcoid patients. Many forms of involvement were reported e.g.; facial nerve palsy, multifocal sensory or motor polyneuropathy or very rarely Guillain Barre' like syndrome. In one clinical series it was estimated that only 10% had primarily peripheral nerve or muscle lesions, where as 90% had primarily CNS or cranial nerve lesions.