Randy Jacobs, M.D. Patient Education

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Pityriasis Rubra Pilaris




Pityriasis rubra pilaris (pit-ih-RYE-ah-sis) is a chronic skin disorder with reddish orange colored scales and papules in a hair follicle distribution. Pityriasis rubra pilaris can occur at any age but it's more common in people between the ages of 10 and 50 years. There are five subtypes of prp: 1. Classical adult. 2. Atypical adult. 3. Classical juvenile. 4. Atypical juvenile. 5. Circumscribed juvenile. It appears as a rash which can last from several weeks to several months. The juvenile forms can be inherited. Most patients clear within three to four years in 80%. Second attacks may occur. Some patients never get rid of prp. The juvenile forms clear faster than the adult forms. Usually, there are no permanent marks as a result of this disease, although some darker-skinned persons may develop long-lasting flat brown spots. All races are affected. Pityriasis rubra pilaris is an uncommon skin rash. Erythroderma (total body redness) can occur in prp patients.


What does it look like?

Pityriasis rubra pilaris often begins with reddish orange colored plaques, scales and papules in a hair follicle distribution on the chest or back. The skin may feel rough to touch as the hair follicles show keratin build up leading to bumps called follicular hyperkeratotic papules. Follicular hyperkeratotic papules occur especially on the dorsal aspects of the fingers and will group together to form larger plaques distributed on the trunk, face, and proximal extremities.  The scalp is particularly scaly, and there is often yellowish pink salmon colored scaling of the palms and soles. The palms and soles show thick scaling called "palmoplantar hyperkeratosis". Certain areas of prp resemble psoriasis except that there are "islands of normal skin" occurring in the middle of redness and thickening. Frequently the person with Pityriasis rubra pilaris will think the patch is ring-worm because of its appearance and will apply anti-fungal medications. This is not beneficial since the rash is not caused by any type of fungus. Within a week or two, a few to many smaller pink patches will occur over the trunk and, to a lesser degree, over the skin of the arms and legs. Lesions may also occur on the neck and, on the face.



What are the symptoms?

Sometimes Pityriasis rubra pilaris can cause a more severe skin reaction with more irritation. Itching occurs in about half of the patients with Pityriasis rubra pilaris and can at times be quite severe, particularly when the patient becomes overheated. Occasionally, there may be other symptoms, including tiredness and aching.  Various environmental or physical factors can cause transient worsening of the rash. These include physical exertion, such as running or bathing in hot water.


What is the cause of this skin disorder?

The cause of Pityriasis rubra pilaris is not known. Studies show that there may be a problem with Vitamin A binding or Vitamin A processing in the skin. Vitamin A may be deficient. Prp is definitely is not caused by a fungus or bacterial infection, and it is not caused by anything that a person has eaten. It also is not due to any known type of allergic reaction, either internal or external. Pityriasis rubra pilaris is not a skin manifestation associated with any type of internal disease such as diabetes, cancer, or kidney disease. In Pityriasis rubra pilaris, the skin cells are turning over at a vary fast rate. The rate is almost, but not quite as fast as in psoriasis.  Pityriasis rubra pilaris also shows plugging of the hair follicles and hyperkeratosis. There is also inflammation within the layers of skin.


Who usually diagnoses it?

The diagnosis of Pityriasis rubra pilaris is usually made by a dermatologist, a physician with special training in skin diseases. The appearance of the rash may not be typical, however, making the diagnosis more difficult. The numbers and sizes of the spots can vary greatly and occasionally the rash can be concentrated in an unusual location, such as the lower body or on the face. Several other skin conditions are similar in appearance to Pityriasis rubra pilaris. Certain skin fungus infections may resemble this rash. Also, reactions to various internal medications, such as antibiotics, fluid pills, and heart medications, may mimic Pityriasis rubra pilaris. Various tests may be necessary to confirm diagnosis. The dermatologist may order blood tests, skin scrapings, or even a biopsy of one of the spots to ascertain a definite diagnosis.


What is the treatment?

Because prp may be related to problems with Vitamin A, oral Vitamin A may help. Accutane or Tegison may also be of use. These are potent Vitamin A medications. Major side effects of Accutane or Tegison include birth defects should a female patient become pregnant while on the medication. Treatment for itch may include external and internal medications for itching. Topically, only gentle, soothing measures should be used, as aggressive treatment has been known to cause the lesions to spread. If symptoms are mild, no treatment may be needed. Various types of soothing medicated lotions and lubricants may be prescribed to combat the rash. LacHydrin 12 is excellent. Individuals with Pityriasis rubra pilaris should take lukewarm, rather than hot, baths. Soap: Soap is bad for Pityriasis rubra pilaris involved skin. Dial, Zest, Lever, Safeguard, Ivory, gels, and Irish Spring are among the worst. Soap removes skin oils needed to hold in moisture. If oils are removed, the skin develops cracks, fissures, and dry inflammation. Soap should not be used on dry or sensitive skin. Most of us use far too much soap. Actually, plain water is often just enough to cleanse the skin. If you can't live without soap, it's OK to use Dove soap for your face, feet, armpits, and groin. Avoid Allergic Items: Pityriasis rubra pilaris involved skin can become itchy when exposed to allergic type substances such as perfumes, dyes, conditioners, powders, anti-perspirants, hair sprays, grasses, plants, fragranced products, shampoos, unrinsed laundry detergents, fabric softener sheets, dog or cat hairs, carpets, chemicals, Aloe Vera, PABA, detergents, acrylic nails, polishes, nickel, elastic, latex, etc. Hair conditioners can induce itch! Please avoid perfumes. Bathing: Persons with Pityriasis rubra pilaris involved skin may bathe or shower twice daily: 1. Use no soap on dry or sensitive skin areas. You may use mild True Moisture® Gentle Face and Body Cleanser, instead of soap. 2. After bathing, thoroughly lubricate your skin using True Moisture® Replenishing Cream available OTC. 3. After your bath, you should not towel dry. Wipe off the water with your hands, then, apply a thin film of True Moisture® Replenishing Cream to your entire body. This film will seal in your new moisture. 4. For shampoo, use OTC fragrance free True Moisture® Gentle Shampoo. Mild lubricants, or anti- pruritic creams, or mild hydrocortisone creams may be used all over the body to soothe the inflammation. Oral antihistamines may be used to reduce itching. Oral corticosteroids may be needed in cases of severe inflammation, but may or may not help. Ultraviolet light treatments are not very helpful. Methotrexate can be used. Mild sun exposure may help speed resolution of lesions; however, care must be taken to avoid sunburn. Expectations (prognosis): Pityriasis rubra pilaris usually goes away within three to four years, but symptoms may recur. Strenuous activity may aggravate the rash. Another important feature of treatment includes reassurance to the patient by the physician that Pityriasis rubra pilaris usually resolves on its own and that Accutane or Soriatane can help in needed.


In Summary...

Pityriasis rubra pilaris is an uncommon, distinctive skin eruption of unknown cause. There are few symptoms. Pityriasis rubra pilaris is usually mild, but can be severe. Pityriasis rubra pilaris is a benign non-contagious skin disease. It can occur at any age but is more common in persons between the ages of 10 to 50 years. The rash typically lasts up to four years. It heals without scarring. There are usually no permanent marks left on the skin as a result of Pityriasis rubra pilaris, although some darkly pigmented persons may have long lasting flat brown spots.