Collagenoma with pseudohypoparathyroidism

Eruptive collagenoma in a Nigerian girl

“…Lesions are usually symmetrical in both familial and eruptive collagenoma, whereas isolated collagenomas present as few lesions localized to parts of the body such as palm of the hand, sole of the foot, and labium majus 6,9,10 . There is usually no associated abnormalities, but an isolated collagenoma has been reported in association with pseudohypoparathyroidism; 11 however, this was probably coincidental. The shargreen patch of tuberous sclerosis, which presents as a skin‐colored or occasionally pigmented mamillated plaque, is a collagenoma, 12 and is one of the well‐recognized cutaneous manifestations of this inherited multi‐organ syndrome.…”

Eruptive Collagenoma in a mongol girl: A rare association

“…However, many authors have reported the presence of plantar collagenoma without any co-existent features of Proteus syndrome [8] isolated collagenoma on the scalp has been reported and can manifest as cutis verticis gyrata [9]. Collagenomas have also been reported in alliance with pseudohypoparathyroidism and hypogonadism [10,11]. Though the pathogenesis of collagenomas is unknown, sporadic collagenomas may be related to trauma, since they appear most frequently in areas subject to friction, in Down syndrome too its pathogenesis is unclear.…”

Isolated pedunculated collagenoma (collagen nevi) of the scalp

“…A collagenoma on the scalp can give the clinical morphology of cutis verticisgyrata and deserves special mention. [8] Collagenomas have also been reported in association with pseudohypoparathyroidism,[12] Down syndrome[13] and hypogonadism. [14] The pathogenesis of collagenomas is not clear.…”