Dermatomyositis Associated With Hypertrichosis

Infrapatellar Hypertrichosis: An Unusual Cutaneous Manifestation of Juvenile Dermatomyositis

“…In 1937, Turner (8) reported the first case of localized acquired hypertrichosis in a 9‐year‐old girl with JDM who had an abundance of thick, pigmented hair on the forearms. In 1948, Reich and Reinhart (9) described a 9‐year‐old boy with thick black hair on the forehead, elbows, temporal regions, and infrapatellar areas. Our patient presented with “tufts” of thick black hair isolated to the infrapatellar regions and a few thick hairs at the elbows.…”

“…Our patient had increased hair growth in a similar distribution, but without associated skin changes. Reich and Reinhart (9) first postulated that abundant and localized arterial hyperemia may be a source of added nutrition for the stimulation of hair follicles. It is possible that a subclinical, localized (i.e., infrapatellar), inflammatory process may have promoted blood flow, resulting in excess hair growth in our patient.…”