[Sebaceous linear nevus syndrome with hemimegalencephaly. Report of a case].

The case of a 7-year-old girl, born from a monochorionic biamniotic pregnancy (with healthy male twin) is presented. The patient showed a congenital brown-yellowish, raised, rough and oval-shaped nevic neoformation of the right temporo-zygomatic region. At 28 days of age she had a right hemiclonic status epilepticus, and from the 8th month of life she presented right sided partial motor seizures. Moreover from the beginning, her development milestones were delayed. When she was 5 years old an electroencephalogram displayed a sharp asymmetrical background activity, a continuous paroxysmal activity on the right hemisphere and independent focal irritative anomalies on the left posterior region. Her computed tomographic scan demonstrated megalencephaly on the right hemisphere. A biopsy specimen of her skin lesion showed the histological characteristics of a nevus sebaceous of Jadassohn. Taken together the clinical, neuroradiological and dermatological data led to the diagnosis of linear nevus sebaceous syndrome.