Hereditary segmental neurofibromatosis: a report of three cases in a family.

Hereditary segmental neurofibromatosis (SNF) is an extremely rare form of SNF with nine families reported till date. SNF is considered to be a result of mosaicism and hereditary transmission is possibly explained by increased susceptibility of mutations at neurofibromatosis gene loci. We report here three members of an Indian family with SNF. Our index case, a 20-year-old woman had multiple soft to firm papules and nodules over right shoulder associated with severe intermittent pain. Her father had three similar nodules over left upper arm and elder sister had two such nodules over right upper arm. The father and elder sister were incidentally diagnosed and they had never sought medical advice considering their lesions to be a familial trait. In the absence of symptoms, many familial cases of SNF are missed thus making any systematic analysis to ascertain its genetic basis difficult.