Rinsho Shinkeigaku (Clinical Neurology)

Case Report

An adult case of neurocutaneous melanosis with acute exacerbation after a long asymptomatic period following excision of a melanocytic nevus

Koji Furukawa, M.D.1)2), Shoji Kikui, M.D., Ph.D.3), Takao Takeshima, M.D., Ph.D.3), Toru Yamamoto, M.D., Ph.D.1) and Akihiko Ozaki, M.D., Ph.D.1)4)

1) Department of Neurology, Osaka Saiseikai Nakatsu Hospital
2) Department of Neurology, Kitano Hospital, Tazuke Kohukai Medical Research Institute
3) Department of Neurology, Social Medical Corporation Kotobukikai Tominaga Hospital
4) Department of Neurology, Japanese Red Cross Osaka Hospital

Neurocutaneous melanosis is caused by postzygotic NRAS mutations in neural crest cells, resulting in large or multiple nevi in the skin and proliferation of leptomeningeal melanocytes in the central nervous system. The onset of neurological symptoms is usually before the age of 2 years, but it can also occur in adults. A 35-year-old male had been asymptomatic for a long time after excision of a large congenital melanocytic nevus, but he developed headache, disturbance of consciousness, and seizure. Methotrexate was ineffective, cerebral pressure was decreased by spinal drainage, and steroid pulse therapy was temporarily effective. Seizures and disturbance of consciousness worsened and the patient died on the 92nd day. Cerebrospinal fluid human melanin black-45 immunostaining and serum 5-Scysteinyldopa (5-S-CD) were useful in diagnosing melanocytic proliferation, and serum 5-S-CD may be useful in predicting prognosis.
Full Text of this Article in Japanese PDF (2172K)

(CLINICA NEUROL, 61: 844−850, 2021)
key words: neurocutaneous melanosis, adult, black nevus, HMB-45 staining, 5-S-CD

(Received: 11-May-21)