National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Disseminated superficial actinic porokeratosis


Other Names:
DSAP
Categories:
Disseminated superficial actinic porokeratosis (DSAP) is a skin condition that causes dry, scaly patches.[1] It is characterized by a large number of small, brownish patches with a distinctive border, found most commonly on sun-exposed areas of the skin (particularly the lower arms and legs).[1][2] DSAP usually starts during the third or fourth decade of life and rarely affects children. Lesions generally are more prominent in the summer and less prominent in the winter. While it is usually benign (not cancerous), squamous cell carcinoma or Bowen’s disease may occasionally develop within patches.[3] DSAP may be inherited in an autosomal dominant matter or may occur sporadically (in people with no family history of DSAP).[3] Some cases are caused by a change (mutation) in the MVK or SART3 genes.[3][4] There is no standard treatment for DSAP, and treatment is generally not effective long-term.[1][2] Sun avoidance may reduce the development of new patches.[1] Treatments that have been beneficial in some people include topical imiquimod cream, topical 5-fluorouracil, and topical vitamin D analogs such as tacalcitol and calcipotriol. Other therapies that have been tested with varying results include cryotherapy, electrodessication (using electrical currents to remove patches), laser ablation, and photodynamic therapy.[1][2][3]
Last updated: 9/12/2018

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.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Porokeratosis 0200044
30%-79% of people have these symptoms
Cutaneous photosensitivity
Photosensitive skin
Photosensitive skin rashes
Photosensitivity
Sensitivity to sunlight
Skin photosensitivity
Sun sensitivity
[ more ] 		0000992
5%-29% of people have these symptoms
Pruritus
Itching
Itchy skin
Skin itching
[ more ] 		0000989
Squamous cell carcinoma 0002860
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Last updated: 7/1/2020

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses include (pre)neoplastic or hyperplastic keratotic skin lesions as well as other forms of porokeratosis, such as porokeratosis of Mibelli or superficial disseminated porokeratosis (similar to DSAP but not triggered by sunlight).
Visit the Orphanet disease page for more information.

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

Organizations Providing General Support

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

  • The British Association of Dermatologists has a patient information leaflet about Disseminated superficial actinic porokeratosis.
  • DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.

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 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.
  • 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 Disseminated superficial actinic porokeratosis. Click on the link to view a sample search on this topic.

Selected Full-Text Journal Articles

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  1. Disseminated superficial actinic porokeratosis. DermNet NZ. April, 2017; https://www.dermnetnz.org/topics/disseminated-superficial-actinic-porokeratosis/.
  2. Kanitakis J. Disseminated superficial actinic porokeratosis. Orphanet. October, 2015; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=79152.
  3. Isabelle Touitou et. al. The expanding spectrum of rare monogenic autoinflammatory diseases. Orphanet Journal of Rare Diseases. 2013; 8:162:http://www.ojrd.com/content/8/1/162.
  4. Linda V Spencer. Porokeratosis. Medscape. August 7, 2017; http://emedicine.medscape.com/article/1059123-overview.