Clinical FeaturesPRP been classified into five groups on the basis of age of onset, clinical features, and prognosis. They are classical adult, atypical adult, classical juvenile, circumscribed juvenile and a typical juvenile.

Classical adultaffects the adults and accounts for nearly half the patients of PRP. It starts as small, yellow pink, acuminate papules caused by follicular hyperkeratosis. At the summit of the papule is small, broken hair.

Atypical adultIt is characterized by ichthyosiform scaling. Eczematous change may develop over it. The scalp hair is often sparse. Keratoderma is coarse and lamellated.

Classical juvenileit resembles classical adult PRP except that its onset is during the first two years.

Circumscribed juvenileIt affects prepubertal children and is characterized by erythematous follicular hyperkeratosis localized to the elbows and the knees. It has no tendency to progress to classical PRP.
Typical juvenileIt begins during the first few years of life and is characterized by erythematous follicular hyperkeratosis and scleroderma like change in the hands and feet. Most familial cases belong to this group and it tends to runa chronic course.

DiagnosisThe diagnosis of PRP is clinical. The histologic changes of PRP, though distinctive, are not diagnostic and only supplement the clinical diagnosis. The histologic features are

• Follicular keratin plug surrounded by perifollicular parakeratosis
• Diffuse hyperkeratosis
• Mild irregular acanthosis
• A mild, chronic, perivascular infiltrate in the superficial dermis
• Liquefaction degeneration of the basal layer

TreatmentOral vitamin A forms the the mainstay of treatment. It is given in a high dose of 150,000 to 500,000 IU daily. Vitamin E, having an apparent synergistic affect, may be combined as an adjuvant to vitamin A.

Other remedies

• Greasy applications (emollients), such as soft white paraffin, reduce the splitting of the thickened palms and soles.
• Steroid creams and ointments soothe but probably do little to get rid of the rash.
• Topical steroids can help to reduce itching for the palms and soles 2% salicylic acid may help.
• The best treatment is Accutane or Soriatane pills. These are closely related "retinoid" medications. While these have many minor side effects, they do not usually cause any serious harm to the body.
• In severe cases acitretin or isotretinoin may be useful for Pityriasis Rubra Pilaris.