[Isolated involvement of the trigeminal nerve of sarcoidosis origin]

Sarcoidosic neurological manifestations are uncommon. Isolated cranial nerve's injury is exceptional. The authors report the case of a 29 year-old woman with a trigeminal nerve tumor. Surgery and anatomopathology led to the diagnosis of sarcoidosic infiltration. No other neurological or extra-neurological localization was found. Cranial fifth nerve injury was observed in 14 cases of the literature. In all cases, trigeminal nerve injury was described as associated with another disease's localization (neurological and/or extra-neurological). This observation seems unusual due to isolated nature of the presentation and complete resolution after surgery. This case illustrated the diagnosis and nosologic difficulties raised by granulomatous lesions, symptomatic or not, in the absence of systemic localization.