Collagenoma, Familial Cutaneous

Clinical Features

Henderson et al. (1968) described 3 brothers with numerous skin nodules on the back. These consisted of thickened dermis due to increased collagenous tissue. One brother had idiopathic myocardiopathy, a second had atrophy of the left iris and severe high frequency sensorineural hearing loss, and the third had recurrent vasculitis. Thus, the cutaneous abnormality may be merely part of a systemic disorder.

Uitto et al. (1979) reported an American black family with 7 affected in 3 generations, including 1 instance of male-to-male transmission. The asymptomatic skin nodules were mainly on the back and chest. Individual lesions varied from a few millimeters to several centimeters in size, were indurated, and showed minimal epidermal changes. Histologically, they were characterized by excessive accumulations of dense, coarse collagen fibers in the dermis. Onset was in the teens and the number of lesions increased during pregnancy. Hormonal influence was suggested.

Hershkovitz et al. (2007) reported a 2-generation family of Jewish origin in which 2 first cousins, aged 6 and 7 years, respectively, had asymptomatic flesh-colored collagenous cutaneous nodules localized mainly over the extremities and lower trunk. Neither child had any other manifestations. The authors referred to this disorder as 'familial cutaneous collagenoma,' but noted the phenotypic overlap with Buschke-Ollendorff syndrome (BOS; 166700). Neither child had evidence of bone lesions, as found in BOS, but individuals with BOS may not show bone lesions. A heterozygous mutation in the LEMD3 gene (607844.0009) was found in both children, but it was also found in the unaffected father of 1 of the children. The findings indicated that abnormal function of LEMD3 may be causally associated with familial collagenomas, which suggested that this family had a variant of BOS without bony abnormalities. Hershkovitz et al. (2007) noted that the findings also suggested that some cases reported as having familial cutaneous collagenomas may have a variant of BOS.