Familial Pityriasis Rubra Pilaris (Adult Classic‐I): A Report of Three Cases in a Single Family

Familial Pityriasis Rubra Pilaris: Case Report and Review

“…4 An additional four cases of familial PRP have since been reported in the literature. 3,[7][8][9] Studies have shown that only up to 6.5% of cases of PRP are familial. 3,8,13 Epidemiology Given the limited number of cases reported, it is difficult to make many generalized statements regarding the epidemiology of this rare subtype.…”

“…1,3,5,6,[8][9][10] The vast majority of the patients presented prior to 20 years of age, except for one family, which reported three cases of adult-onset familial PRP. 7…”

“…The most common mode of inheritance is autosomal dominant with variable expression and reduced penetrance. 5,[7][8][9] Autosomal recessive transmission has been documented as well as PRP in monozygotic twins. 1,6 Moreover, some researchers theorize that the familial, atypical, and circumscribed juvenile types of PRP are caused by a process distinct from that of the classic type.…”

“…[3][4][5][6][7][8][9][10] The first documented case was published in 1910, and 36 subsequent familial cases of PRP have been reported in the literature. 3,[7][8][9][11][12][13] Studies have shown that only up to 6.5% of cases of PRP are familial. 3,8,13 The majority of these appear to be inherited as autosomal dominant with variable expression and reduced penetrance.…”

“…3,8,13 The majority of these appear to be inherited as autosomal dominant with variable expression and reduced penetrance. 5,[7][8][9] We present a case of PRP inherited in an autosomal dominant fashion in a 29year-old female and her 4-year-old daughter. A comprehensive, up-to-date literature review of familial PRP is included.…”