Rare Ophthalmology News

Disease Profile

Pityriasis rubra pilaris

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

1-9 / 1 000 000

US Estimated

Europe Estimated

Age of onset

All ages





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable



Congenital and Genetic Diseases; Skin Diseases


Pityriasis rubra pilaris (PRP) refers to a group of skin conditions that cause constant inflammation and scaling of the skin.[1] People with PRP have reddish, scaly patches that may occur everywhere on the body, or only on certain areas.[2][3] Some people with PRP also develop thickened skin on the underside of the hands and feet (palmoplantar keratoderma), various nail abnormalities, and/or thinning of the hair.[4] There are several types of PRP classified by age when symptoms begin, body areas involved, and whether other conditions are present.[2][5] This condition occurs in adults (adult onset PRP) as well as children (juvenile onset PRP).[4]

In most cases, PRP is not inherited and the cause is not known. In some people, particularly some with type V (the “atypical juvenile type”), PRP has autosomal dominant inheritance and may be caused by mutations in the CARD14 gene.[6][7]

Treatment options vary based on symptoms and severity. No one treatment works for all people with PRP. Examples of treatment options include topical emollients or medications, oral retinoids, and/or immunosuppressants.[2][4][5]


Features of this condition vary greatly from person to person. Signs and symptoms often get worse over time and may affect the skin, nails, mucous membranes, and eyes.[2] Signs and symptoms may include:

  • Redness and scaling of the skin and scalp, which often develops into itchy, orange-red plaques. Plaques may first occur on only some parts of the body, but may eventually spread over the whole body.[4] The elbows, knees, ankles, hands and feet are most commonly affected.[2]
  • Thickening of the skin on the palms and soles (palmoplantar keratoderma).[5]
  • Thickening, discoloration, or shedding of the nails.[5]
  • Thinning of the hair.[4]
  • Plaques and irritation in the mouth.[5]
  • Dryness of the eyes and/or ectropion (outward turning of the eyelid).[5]
  • Reduced quality of life associated with persistent pain, itching, or sleep disturbances.[3]

Information about the types of PRP and how they differ is available from DermNet New Zealand.

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Irregular hyperpigmentation
Palmoplantar keratoderma
Thickening of palms and soles
30%-79% of people have these symptoms
Itchy skin
Skin itching

[ more ]

Subungual hyperkeratosis
Thickened, discolored skin under nail
5%-29% of people have these symptoms
Abnormal oral cavity morphology
Abnormality of the oral cavity
Eyelid turned out
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance
Erythematous plaque
Infantile onset
Onset in first year of life
Onset in infancy

[ more ]

Keratosis pilaris
Chicken skin


In the vast majority of people with PRP, the cause is unknown.[2] Most cases are thought to result from a combination of unknown genetic factors and environmental triggers.[3]

Rarely, PRP is due to changes (mutations) in a gene called CARD14.[8][9][6] Mutations in this gene are found particularly in people with PRP type V. This gene gives the body instructions for making a protein involved in regulating the body's immune responses and inflammatory reactions. While the protein is present in many of the body’s tissues, it is found in great amounts in the skin. Mutations in this gene are thought to trigger an abnormal inflammatory response, leading to the signs and symptoms of PRP.[8]


Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.


    PRP can be difficult to treat and many treatment options have been tried. There is little information on which treatments are best because none have been studied in large clinical trials. Treatment options may vary based on the symptoms in each person but often involve a combination of medicines taken internally and applied topically to the skin.[2]

    Topical therapy options may include corticosteroids, keratolytics, calcipotriol, tretinoin, and tazarotene. For people with mild PRP, using one or more of these may be enough to control symptoms.[4]

    Most people with PRP also need additional medicines to control their symptoms, especially if the condition affects a large part of the body.[4] Oral retinoids are usually tried first.[4] Examples include acitretin and isotretinoin.[5] Methotrexate, an immune system suppressant, may be tried when oral retinoids are not safe for a particular person, or when they have stopped working.[4] Other immune system suppressants that have been helpful in some case reports include cyclosporine and azathioprine.[4][5] Biologic therapies may be another option, based on limited data. Examples include various biologic TNF-alpha inhibitors and ustekinumab.[5]

    For more detailed information about treatment options for PRP, you can view information from Medscape Reference or the National Organization for Rare Disorders (NORD).

    Many of these treatments have shown results in only a few patients, and some can have serious side effects. The risks and benefits of each treatment option should be discussed with your doctor.


    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Social Networking Websites

        Learn more

        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

        • DermNet New Zealand is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
        • Genetics Home Reference (GHR) contains information on Pityriasis rubra pilaris. This website is maintained by the National Library of Medicine.
        • The Merck Manuals Online Medical Library provides information on this condition for patients and caregivers.
        • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

          In-Depth Information

          • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
          • The Merck Manual for health care professionals provides information on Pityriasis rubra pilaris.
          • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
          • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
          • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
          • PubMed is a searchable database of medical literature and lists journal articles that discuss Pityriasis rubra pilaris. Click on the link to view a sample search on this topic.


            1. Pityriasis rubra pilaris. MedlinePlus. April 15, 2015; https://www.nlm.nih.gov/medlineplus/ency/article/001471.htm.
            2. Oakley A. Pityriasis rubra pilaris. DermNet New Zealand. October, 2015; https://www.dermnetnz.org/topics/pityriasis-rubra-pilaris/.
            3. Pityriasis Rubra Pilaris. National Organization for Rare Disorders (NORD). 2017; https://rarediseases.org/rare-diseases/pityriasis-rubra-pilaris.
            4. Katsambas A and Dessinioti C. Pityriasis rubra pilaris. UpToDate. Waltham, MA: UpToDate; March 10, 2017; https://www.uptodate.com/contents/pityriasis-rubra-pilaris.
            5. Shenefelt PD. Pityriasis Rubra Pilaris. Medscape Reference. April 17, 2017; https://emedicine.medscape.com/article/1107742-overview.
            6. Takeichi T, Sugiura K, Nomura T, et al.. Pityriasis Rubra Pilaris Type V as an Autoinflammatory Disease by CARD14 Mutations. JAMA Dermatol. January 1, 2017; 153(1):66-70. https://www.ncbi.nlm.nih.gov/pubmed/27760266.
            7. Lwin SM, Hsu CK, Liu L, Huang HY, Levell NJ, McGrath JA. Beneficial effect of ustekinumab in familial pityriasis rubra pilaris with a new missense mutation in CARD14. Br J Dermatol. March 16, 2017; [Epub ahead of print]:https://www.ncbi.nlm.nih.gov/pubmed/28301045.
            8. Familial Pityriasis Rubra Pilaris. Genetics Home Reference. March, 2013; https://ghr.nlm.nih.gov/condition/familial-pityriasis-rubra-pilaris.
            9. O'Neill MJF. Pityriasis Rubra Pilaris; PRP. Online Mendelian Inheritance in Man (OMIM). July 31, 2012; https://www.omim.org/entry/173200.

            Rare Ophthalmology News

            fascinating Rare disease knowledge right in your inbox
            Subscribe to receive