Nevus sebaceus of Jadassohn
Overview
Nevus sebaceous of Jadassohn: A rare genetic neurocutaneous disorder characterized by epidermal nevi associated with central nervous and skeletal system abnormalities
Symptoms
The list of signs and symptoms mentioned in various sources for Nevus sebaceous of Jadassohn includes the 13 symptoms listed below: * Asymmetric overgrowth * Advanced bone age * Nevus sebaceous * Hyperpigmented nevus sebaceous * Hyperkeratosis * Trunk lesions * Limb lesions * Midfacial linear lesions * Seizures * Major motor seizures * Focal seizures * Minor motor seizures * Mental deficiency
Causes
History * Most frequently, a solitary, hairless patch is noted on the scalp at birth or in early childhood. A velvety tan or orange-yellow plaque may also occur on other areas of the head and the neck. * Hormonal influences from the mother may briefly increase the prominence in an infant, whereas pubertal hormones enhance the verrucoid appearance in an adolescent. * Nevus sebaceus has a predilection for the scalp (vertex) and less commonly occurs on the face, around the ears, on the neck, or on the trunk. Nevus sebaceus occurring exclusively in the oral cavity has also been reported.2 Physical * Nevus sebaceus passes through 3 clinically distinct stages. o At birth or in early infancy, nevus sebaceus appears as a hairless, solitary, linear or round, slightly raised, pinkish, yellow, orange, or tan plaque, with a smooth or somewhat velvety surface. The nevus is usually on the scalp, often near the vertex or on the face. Extensive lesions not limited to the head have been reported. o In adolescence, the lesion becomes verrucous and nodular, round, oval, or linear in shape, varying in length from about 1 cm to more than 10 cm. They most commonly occur as a single lesion, but they may be multiple and extensive. o Later in life, some lesions may develop various types of appendageal tumors, such as trichoblastoma; syringocystadenoma papilliferum; basal cell carcinoma; and, less commonly, nodular hidradenoma, sebaceous epithelioma, apocrine cystadenoma, eccrine carcinoma, squamous cell carcinoma, sebaceous carcinoma, spiradenoma, and keratoacanthoma. * Nevus sebaceus lesions, especially when large, may be associated with multiple internal abnormalities, similar to those reported in linear epidermal nevus syndrome.3 o Associated problems may include intracranial masses, seizures, mental retardation, skeletal abnormalities, pigmentary changes, ocular lesions, and hamartomas of the kidney. Mediastinal lipomatosis has also been reported. o Epidermal nevus syndrome (Jadassohn nevus phakomatosis) is the combination of extensive sebaceous nevi with disorders of the central nervous system, the bone, and the eye. Some of the more common abnormalities include epilepsy; mental retardation; seizures or other neurologic defects; skeletal deformities, such as vitamin D–resistant rickets, spina bifida, bone hyperplasia, or bone hypertrophy; and ocular lesions, such as ptosis, nystagmus, optic nerve hypoplasia, and oculomotor dysfunction. o Recently, a case of linear squamous cell papilloma associated with sebaceus nevus syndrome was described in a 7-year-old boy.