Epidermal nevus syndrome

Abstract

The epidermal nevus syndrome (ENS) is a sporadic neurocutaneous disorder that consists of epidermal nevi and congenital anomalies involving the brain and other systems. From among over 60 patients with ENS presenting with neurologic manifestations, we identified 17 who had hemimegalencephaly based on pathologic or radiologic studies. Associated brain and neurologic abnormalities included gyral malformations in 12 of 12, mental retardation in 13 of 14, seizures in 16 of 17 (including 9 with infantile spasms), and contralateral hemiparesis in 7 of 12. All had ipsilateral epidermal nevi of the head, and several had ipsilateral facial hemihypertrophy. We concluded that these abnormalities comprise a recognizable neurologic variant of ENS that we believe represents the full expression of primary brain involvement. Several patients also had evidence of acquired brain lesions such as infarcts, atrophy, porencephaly, and calcifications, which are best explained by prior ischemia or hemorrhage. Given repeated observations of blood vessel anomalies in ENS patients, we hypothesize that underlying vascular dysplasia predisposes to these acquired lesions. The same cause may be invoked to explain the wide variety of neurologic symptoms reported in ENS patients without hemimegalencephaly. While the cause of ENS remains unknown, several observations suggest a somatic mutation.

Epidermal nevus syndrome: An unusual cerebellar involvement

“…The phenomenon of the blaschkoid disposition, a recognized feature of cutaneous genetic mosaicism, supports the current idea that the multiorganic manifestations of ENS are due to genetic mosaicism [3]. Neurological manifestations include mental retardation and seizures [2]. The reported brain involvement in ENS is usually supratentorial, in most cases consisting of hemimegalencephaly, pachygyria and/or ventriculomegaly.…”

Hemimegalencephaly and Linear Nevus Sebaceous Syndrome

“…9 The epidermoid or linear nevus sebaceous is present over the head and neck. 10 It is a triphasic lesion, which is bland in infancy, has papillomatous hyperplasia in adolescence, and associated with skin-appendage tumors in adults. 11 A paramidline location of the nevus is typical with the lesion often vertically oriented from the middle of the forehead along the nose to the upper lip just lateral to midline.…”

“…Cardiac anomalies include coarctation of the aorta and ventricular septal defect. 10 With increasing age there is an increased incidence of tumors including skin cancer, breast, salivary gland, stomach, esophageal, bladder cancer, and ameloblastoma. 10 LNSS is also associated with so-called tumorigenic rickets due to a phosphaturic agent excreted by the nevus.…”

“…10 With increasing age there is an increased incidence of tumors including skin cancer, breast, salivary gland, stomach, esophageal, bladder cancer, and ameloblastoma. 10 LNSS is also associated with so-called tumorigenic rickets due to a phosphaturic agent excreted by the nevus. 12 HME is probably the dominant neuropathologic manifestation of LNSS 10 and has the characteristic clinical present of mental retardation, seizures including infantile spasms, and hemiparesis.…”

“…10 LNSS is also associated with so-called tumorigenic rickets due to a phosphaturic agent excreted by the nevus. 12 HME is probably the dominant neuropathologic manifestation of LNSS 10 and has the characteristic clinical present of mental retardation, seizures including infantile spasms, and hemiparesis. The exact frequency of HME in LNSS is not certain but may be as high as 50%.…”