[Primary leptomeningeal melanomatosis in a 6-year-old child].

A case of primary leptomeningeal melanomatosis without cutaneous lesions is reported. The clinical findings for a six months period were: intracranial hypertension syndrome, progressive cranial polineuropathy and a spinal involvement in a six years old child. CT brain scan showed enlarged subarachnoid spaces without contrast enhancement. MRI brain scan evidenced furthermore a focal lesion in right talamus. MRI spinal scan was normal. Examination of CSF showed elevated protein and reduced glucose concentrations as well as mild pleocytosis. Serologies and cultures investigating viral, bacterial, mycobacterial, fungal or parasitic infections resulted negative. CSF cytologic examination failed to show malignant cells. Postmortem diagnosis after neuropathological examination was made. This is an uncommon case of primary leptomeningeal melanomatosis, presenting the difficulty of diagnosis when cutaneous lesions are not present.