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

Palmoplantar keratoderma



Palmoplantar keratoderma (PPK) is a group of skin conditions characterized by thickening of the skin on the palms of the hands and soles of the feet. PPK can also be a feature of various underlying syndromes.[1] In rare forms of PPK, organs other than the skin may also be affected. PPK can be either acquired during the lifetime (more commonly) or inherited. Acquired PPKs may arise due to changes in a person's health or environment.[2] Inherited PPKs are caused by genetic mutations that result in abnormalities of keratin, a skin protein. Depending on the genetic cause, inheritance can be autosomal dominant or autosomal recessive.[1][2] Treatment is aimed at softening the thickened skin to make it less noticeable and relieve discomfort.[2]
Last updated: 12/29/2016

Palmoplantar keratoderma (PPK) can be either acquired during the lifetime (more commonly) or inherited. Acquired PPK may arise due to changes in a person's health or environment.[2]

Inherited forms of PPK are caused by genetic mutations that result in abnormalities of keratin (a skin protein). These forms of PPK may be present in more than one family member. Mutations in several genes can cause an inherited form of PPK. Depending on the gene involved, inheritance can be autosomal dominant or autosomal recessive.[1][2]

Autosomal dominant inheritance means that having a mutation in only one copy of the responsible gene in each cell is enough to cause features of the condition. In some cases, an affected person inherits the mutated gene from an affected parent. In other cases, the mutation occurs for the first time in a person with no family history of the condition. This is called a de novo mutation. When a person with a mutation that causes an autosomal dominant condition has children, each child has a 50% (1 in 2) chance to inherit that mutation. For this reason, it is not uncommon for an autosomal dominant condition to be present in more than one generation in a family.

Autosomal recessive inheritance means that to be affected, a person must have a mutation in both copies of the responsible gene in each cell. Affected people inherit one mutated copy of the gene from each parent, who is referred to as a carrier. Carriers of an autosomal recessive condition typically do not have any signs or symptoms (they are unaffected). When 2 carriers of an autosomal recessive condition have children, each child has a:
  • 25% chance to be affected
  • 50% chance to be an unaffected carrier like each parent
  • 25% chance to be unaffected and not a carrier

A person with an autosomal recessive condition can have an affected child only if the child's other parent is at least a carrier of the same condition. In most cases, autosomal recessive conditions affect only one generation in a family, such as siblings.

People with personal questions regarding whether PPK is inherited, or how it may be inherited, are encouraged to speak with a genetic counselor or other genetics professional. A genetics professional can help by:

  • thoroughly evaluating the family history
  • addressing questions and concerns
  • assessing recurrence risks
  • facilitating genetic testing if desired
  • discussing reproductive options
Last updated: 12/29/2016

Diagnosis of palmoplantar keratoderma (PPK) may involve a clinical exam, evaluating the medical and family history, histopathology (viewing tissue from a skin biopsy under a microscope), and genetic testing (if hereditary PPK is suspected).

In addition to identifying thickened skin on the palms of the hands and soles of the feet, an exam is needed to check for involvement of other areas of the skin; the nails, hair, and teeth; and other organs of the body.[3] Distinguishing between acquired and hereditary PPK is important. Acquired PPK usually occurs later in life and may be due to many causes, such as drugs, malnutrition, chemicals, systemic disease, cancer, and infection.[4]

The family history may be helpful in identifying hereditary PPK and establishing the inheritance pattern.[3] Lack of a family history is not necessarily evidence of acquired PPK. Autosomal recessive PPK can appear sporadically from unaffected parent carriers, and autosomal dominant PPK can also occur sporadically due to a new mutation in an affected person (a de novo mutation).[4]

Histopathology of a biopsy from affected skin should be part of the diagnostic workup. This may show more specific features characteristic of a subtype of PPK. Distinguishing between epidermolytic and nonepidermolytic forms of PPK is helpful for treatment options, as epidermolytic forms tend to worsen on systemic retinoids. Histopathology is also needed to rule out other conditions with overlapping features.[3]

Genetic testing allows for a precise diagnosis as well as counseling with regard to the inheritance pattern and risk of recurrence.[3] The Genetic Testing Registry (GTR) provides information about the genetic tests for each hereditary type of PPK. 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.
Last updated: 12/30/2016

Treatment of both hereditary and acquired palmoplantar keratodermas (PPK) is difficult.[1] The goal of treatment is to soften the thickened skin and make it less noticeable.[2] In many cases, treatment only results in short-term improvement and often has unwanted side effects.[1] For people with acquired PPK, it is important to screen for systemic illnesses, infections, culprit drugs, and neoplasia (tumor formation). Treating the underlying condition or stopping possible triggers is the most effective treatment for acquired PPK.

Treatment options may depend on the specific type of PPK a person has and may include:[1][2] Currently, to our knowledge, there is no way to prevent PPK in a person who has inherited PPK but has not yet developed symptoms.
Last updated: 5/17/2017

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Palmoplantar keratoderma. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Patient Registry

  • A registry supports research by collecting of information about patients that share something in common, such as being diagnosed with Palmoplantar keratoderma. The type of data collected can vary from registry to registry and is based on the goals and purpose of that registry. Some registries collect contact information while others collect more detailed medical information. Learn more about registries.

    Registries for Palmoplantar keratoderma:
    The National Registry for Ichthyosis & Related Skin Disorders
     

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


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 NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
  • The Foundation for Ichthyosis Related Skin Types has a fact sheet on Palmoplantar Keratodermas (PPK). To view this page, click on the link.

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.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Palmoplantar keratoderma. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.


  1. Charny JW. Keratosis Palmaris et Plantaris. Medscape Reference. June 10, 2016; http://emedicine.medscape.com/article/1108406-overview#showall.
  2. Stanway A. Palmoplantar keratoderma. DermNet New Zealand. 2005; http://www.dermnetnz.org/topics/palmoplantar-keratoderma/.
  3. Has C, Technau-Hafsi K. Palmoplantar keratodermas: clinical and genetic aspects. J Dtsch Dermatol Ges. February, 2016; 14(2):123-139.
  4. Sakiyama T, Kubo A. Hereditary palmoplantar keratoderma "clinical and genetic differential diagnosis". J Dermatol. March, 2016; 43(3):264-274.