[Neurocutaneous melanosis]

Abstract

Introduction: Neurocutaneous melanosis is an infrequent condition characterized by the presence of numerous gigantic cutaneous naevi and melanocytic infiltration of the central nervous system and/or the leptomeningeal layers. Different clinical features may be seen: endocranial hypertension due to hydrocephalus, cranial nerve paralysis, myelopathy, convulsive seizures, etc. The prognosis is considered to be malignant. Only positive CNS histological findings confirm the diagnosis.

Clinical case: We present the case of a man with cutaneous lesions compatible with the diagnosis of neurocutaneous melanosis since birth, with benign self-limiting epilepsy in early childhood. Cerebral CT and MR scans were normal until the age of 17, when hipper-signal lesions appeared on MR, infiltrating the leptomeninges of the deep temporal pole and anterior aspect of the cerebral peduncles, which suggested the presence of melanocytes in the CNS.

Conclusions: There are cases of neurocutaneous melanosis with a good medium-term prognosis and benign manifestations until infiltration of the CNS occurs. Then they start to show the classical behavior of cases with a malignant prognosis. MR should be included as part of the diagnostic criteria for neurocutaneous melanosis. MR should be done periodically in patients with cutaneous lesions suggestive of this condition.