Synonyms

• Devergie Disease
• Lichen Acuminatus
• Lichen Psoriasis
• Lichen Ruber Acuminatus
• Pityriasis Pilaris
• PRP

Disorder Subdivisions

• None

Related Disorders List

Information on the following diseases can be found in the Related Disorders section of this report:

• Lichen Planus
• Pityriasis Rosea
• Psoriasis

General Discussion

Pityriasis Rubra Pilaris is a mildly itchy chronic skin disorder that is possibly caused by an inherited metabolic defect. Initially, the disorder is characterized by elevated spots (papules) on the skin. These spots grow and become connected, producing red plaques over large areas.

Symptoms

Pityriasis Rubra Pilaris is initially characterized by skin lesions described as mildly itchy, sharply pointed, horn-like, brownish-red to rosy yellow- colored papules. These papules usually occur on the back of the wrists, the outside of the forearms, underarm folds, elbows, knees, backs of the hands, and fingers. When the papules grow and connect together they produce dry, scaly, rough, red plaques over large areas of the skin. Gray, brittle nails and excessive oiliness of the glands on the scalp (seborrhea) and face may also occur. Often the edge of the eyelids are turned outward (ectropion).

Causes

The specific underlying cause of Pityriasis Rubra Pilaris is unknown. Researchers indicate that the condition may be hereditary or acquired. In many cases, Pityriasis Rubra Pilaris appears to occur randomly for no known reason (sporadically). However, in some affected individuals, evidence suggests that the disorder may be inherited as an autosomal dominant trait. Human traits, including the classic genetic diseases, are the product of the interaction of two genes for that condition, one received from the father and one from the mother.



In dominant disorders, a single copy of the disease gene (received from either the mother or father) will be expressed "dominating" the other normal gene and resulting in the appearance of the disease. The risk of transmitting the disorder from affected parent to offspring is 50 percent for each pregnancy regardless of the sex of the resulting child.



Some researchers suggest that Pityriasis Rubra Pilaris may result from abnormalities in vitamin A metabolism. (Metabolism refers to the chemical processes occurring in the body.) However, such research has not been definitive, necessitating further investigation.

Affected Populations

Pityriasis Rubra Pilaris is a rare disorder that may develop during childhood or adulthood. The condition appears to occur in males and females in relatively equal numbers. Reported cases include several affected individuals in a number of multigenerational families (kindreds) as well as isolated instances of the disorder.

Related Disorders

Symptoms of the following disorders can be similar to those of Pityriasis Rubra Pilaris. Comparisons may be useful for a differential diagnosis:



Lichen Planus is a recurrent, itchy, inflammatory eruption characterized by small separate, angular spots that may combine into rough scaly patches. It is often accompanied by lesions in the mouth. Women are most commonly affected, although some cases have begun during childhood. The exact cause of this disorder is unknown, though some minerals such as bismuth, arsenic, gold, or exposure to certain chemicals used in developing color photographs may cause an eruption indistinguishable from Lichen Planus. (For more information on this disorder, choose "Lichen Planus" as your search term in the Rare Disease Database.)



Pityriasis Rosea is a self-limited, mild, inflammatory skin disorder characterized by scaly lesions found most commonly on the trunk. The disorder is possibly due to an unidentified infectious agent. It may occur at any age but is seen most frequently in young adults. In temperate climates, incidence is highest during spring and autumn.



Psoriasis is a common chronic and recurrent skin disorder characterized by dry, well-circumscribed silvery gray scaling spots (papules) or plaques on the scalp, elbows, knees and/or the buttocks. (For more information on this disorder, choose "Psoriasis" as your search term in the Rare Disease Database.)

Standard Therapies

Pityriasis Rubra Pilaris tends to follow a natural waxing and waning course, with episodes in which there is periodic worsening (exacerbation) or cessation (remission) of symptoms. As a result, according to many researchers, it may be difficult to evaluate the effectiveness of particular therapies. However, standard therapy for the condition typically includes treatment with vitamin A or synthetic vitamin A compounds (retinoids) administered topically or by mouth (orally). Synthetic retinoids prescribed for the treatment of Pityriasis Rubra Pilaris may include isotretinoin or etretinate. In addition, in some cases, low-dose methotrexate, a medication that is often used to fight abnormal cell proliferation (antineoplastic drug), may be prescribed.

Investigational Therapies

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.



For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:



Tollfree: (800) 411-1222

TTY: (866) 411-1010

Email: prpl@cc.nih.gov



For information about clinical trials sponsored by private sources, contact:

www.centerwatch.com

References

ONLINE MENDELIAN INHERITANCE IN MAN (OMIM). Victor A. McKusick, Editor; Johns Hopkins University, Last Edit Date 6/13/95. Entry Number 173200.



HARRISON'S PRINCIPLES OF INTERNAL MEDICINE, 14th Ed.: Anthony S. Fauci et al., Editors; McGraw-Hill Companies, Inc., 1998. P. 313.



NELSON TEXTBOOK OF PEDIATRICS, 15th Ed.: Richard E. Behrman, Editor; W.B. Saunders Company, 1996. Pp. 1866-67.



PITYRIASIS RUBRA PILARIS, VITAMIN A AND RETINOL-BINDING PROTEIN: A CASE STUDY: P.C. van Voorst Vader et al.; Acta Derm Venereol (1984; 64(5)). Pp. 430-32.



CHILDHOOD-ONSET PITYRIASIS RUBRA PILARIS WITH IMMUNOLOGIC ABNORMALITIES. D. Shvili et al.; Pediatr Dermatol (May 1987; 4(1)). Pp. 21-23.



ISOTRETINOIN TREATMENT OF PITYRIASIS RUBRA PILARIS. C.H. Dicken; J Am Acad Dermatol (Feb 1987; 16(2 Part 1)). Pp. 297-301.



EARLY PRESENTATION OF PITYRIASIS RUBRA PILARIS. S.E. Caplan et al.; Cutis (Dec 1997; 60(6)). Pp. 291-96.



ADULT PITYRIASIS RUBRA PILARIS: A 10-YEAR CASE SERIES. B.D. Clayton et al.; J Am Acad Dermatol (Jun 1997; 36(6 Pt 1)). Pp. 959-64.



PITYRIASIS RUBRA PILARIS: A RETROSPECTIVE ANALYSIS OF 43 PATIENTS. K.B. Sorensen et al.; Acta Derm Venereol (Sep 1999; 79(5)). Pp. 405-06.



PITYRIASIS RUBRA PILARIS. M.R. Albert et al.; Int J Dermatol (Jan 1999; 38(1)). Pp. 1-11.

Resources

Foundation for Ichthyosis & Related Skin Types

2616 N Broad Street

Colmar, PA 18915

Tel: (215)997-9400

Fax: (215)997-9403

Tel: (800)545-3286

Email: info@firstskinfoundation.org

Internet: http://www.firstskinfoundation.org



NIH/NationaI Institute of Arthritis and Musculoskeletal and Skin Diseases

Information Clearinghouse

One AMS Circle

Bethesda, MD 20892-3675

USA

Tel: (301)495-4484

Fax: (301)718-6366

Tel: (877)226-4267

TDD: (301)565-2966

Email: NIAMSinfo@mail.nih.gov

Internet: http://www.niams.nih.gov/



Pityriasis Rubra Pilaris Support Group

Email: rgreene@temple.edu

Internet: http://www.prp-support.org



MUMS National Parent-to-Parent Network

150 Custer Court

Green Bay, WI 54301-1243

USA

Tel: (920)336-5333

Fax: (920)339-0995

Tel: (877)336-5333

Email: mums@netnet.net

Internet: http://www.netnet.net/mums/



Genetic and Rare Diseases (GARD) Information Center

PO Box 8126

Gaithersburg, MD 20898-8126

Tel: (301)251-4925

Fax: (301)251-4911

Tel: (888)205-2311

TDD: (888)205-3223

Email: http://rarediseases.info.nih.gov/GARD/EmailForm.aspx

Internet: http://rarediseases.info.nih.gov/GARD