What are the other Names for this Condition? (Also known as/Synonyms)

• Diffuse Hereditary PPK

What is Diffuse Hereditary Palmoplantar Keratoderma? (Definition/Background Information)

• Palmoplantar Keratoderma (PPK) is a benign skin condition, wherein there is thickening of skin (keratoderma) of the palms and/or soles. The skin condition is considered to be a pattern of skin findings and not a condition in itself
• The abnormal skin thickening can be focal (localized keratoderma), widespread (diffused keratoderma), or punctate-type (with the appearance of tiny bumps)
• Diffuse Hereditary Palmoplantar Keratoderma is a type of palmoplantar keratoderma that is caused by genetic abnormalities that may be inherited in an autosomal dominant or autosomal recessive manner. In this condition, the presence of keratoderma or thickened skin is diffusely present in the soles and palms of the affected child
• The condition begins as reddish skin on the palms of the hands and soles of the feet, during infancy or early childhood. With time (2-3 years), the skin thickens and becomes shiny or waxy in appearance. Often, there is a perceivable demarcation between the affected and non-affected skin regions on the palms and soles
• A diagnosis of Diffuse Hereditary Palmoplantar Keratoderma can be made by clinical exam, skin exam, and various other diagnostic tools including dermoscopy and wood’s lamp examination
• The treatment of Diffuse Hereditary Palmoplantar Keratoderma is based on the underlying cause of the condition. But, the treatment of thickened skin may include the use of moisturizers, topical creams, and skin softeners
• The prognosis depends upon the severity of the symptoms, the response to treatment, and most importantly upon the severity of the underlying condition. The prognosis of Diffuse Hereditary Palmoplantar Keratoderma is determined on a case-by-case basis

Who gets Diffuse Hereditary Palmoplantar Keratoderma? (Age and Sex Distribution)

• Diffuse Hereditary Palmoplantar Keratoderma is a congenital disorder with an onset at birth in many cases
• The condition affects both males and females
• It is seen worldwide and all racial and ethnic groups may be affected

What are the Risk Factors for Diffuse Hereditary Palmoplantar Keratoderma? (Predisposing Factors)

• The risk factor for Diffuse Hereditary Palmoplantar Keratoderma includes a positive family history of the condition
• Diffuse Hereditary PPK can be associated with a variety of congenital syndromes

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Diffuse Hereditary Palmoplantar Keratoderma?

• Diffuse Hereditary Palmoplantar Keratoderma is a genetic disorder
• It can be caused by genetic abnormalities that are passed down (through families) in an autosomal dominant or autosomal recessive pattern

Autosomal dominant: Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The abnormal gene dominates, masking the effects of the correctly function gene. If an individual has an autosomal dominant condition, the chance of passing the abnormal gene on to their offspring is 50%. Children, who do not inherit the abnormal gene, will not develop the condition or pass it on to their offspring.

Autosomal recessive: Autosomal recessive conditions are traits or disorders that occur when two copies of an abnormal gene have been inherited on a non-sex chromosome. If both parents have an autosomal recessive condition, there is a 100% likelihood of passing on the mutated genes to their children. If, however, only one mutant copy of the gene is inherited, the individual will be a carrier of the condition, but will not be present with any symptoms. Children, born to two carriers, have a 25% chance of being homozygous dominant (unaffected), a 50% chance of being heterozygous (carrier), and a 25% chance of being homozygous recessive (affected).

What are the Signs and Symptoms of Diffuse Hereditary Palmoplantar Keratoderma?

In general, the signs and symptoms associated with Diffuse Hereditary Palmoplantar Keratoderma may include:

• The presence of abnormally-thickened skin on the palms of the hands and soles of the feet
• The skin thickening involves the entire palm and sole (diffused)
• Sometimes, involvement of the skin on the hands and feet (and of the wrists and ankles, in some cases) may be seen. This is known as transgradient keratoderma; while, if portions of the hands/feet are not involved, it is called non-transgradient keratoderma
• Atrophy of the fingers and toes can occur in rare cases
• Increased sweating
• Secondary infections, mostly of the feet, may take place
• Normal activities that involve the use of one’s hands and feet may be severely affected
• Other systemic and skin signs and symptoms may be present. In such cases, the condition is said to be associated with other abnormalities, which may be manifested as:
  • Deafness
  • Abnormalities affecting the hair, nail, and teeth
  • Internal organs may be affected

Onset of the diffuse palmoplantar condition occurs in the following manner:

• The condition has an early onset in childhood with the appearance of reddish skin on the palmoplantar areas (palms and soles)
• By the time the child reaches the age of 3 or 4 years, the skin on the palms and soles tend to thicken and take on a pale yellow color
• The texture of the skin is shiny or waxy and most part of the palms and soles may be affected
• In many cases, the affected and non-affected portions of the hand/feet are easily recognised; a sharp differentiation can be observed

How is Diffuse Hereditary Palmoplantar Keratoderma Diagnosed?

The diagnosis of Diffuse Hereditary Palmoplantar Keratoderma may involve:

• A complete evaluation of medical history along with a thorough examination of the skin lesions by a dermatologist
• The healthcare provider may ask many questions related to the individual’s age, family medical history, current medications, cosmetics, body lotions used, other medical conditions, infections, etc.
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Genetic testing to identify the gene involved
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis
• Tests and procedures to establish the underlying cause of keratoderma will be undertaken

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Diffuse Hereditary Palmoplantar Keratoderma?

• Complications associated with Diffuse Hereditary Palmoplantar Keratoderma include complications associated with the cause of the condition
• Depending on the cause, severe skin and systemic complications may arise
• Some forms of hereditary keratoderma are more prone to the development of carcinomas

How is Diffuse Hereditary Palmoplantar Keratoderma Treated?

The treatment of Diffuse Hereditary Palmoplantar Keratoderma is based upon the cause of the condition. Symptomatic treatment of the various abnormalities associated with this form of keratoderma may be undertaken.

However, the skin thickening may be addressed through skin softening treatment measures such as:

• Use of moisturizing creams and lotions; use of ointments containing vitamin D
• Use of topical and systemic retinoids
• Administration of keratolytics (medicine containing salicylic acid)

How can Diffuse Hereditary Palmoplantar Keratoderma be Prevented?

Currently, Diffuse Hereditary Palmoplantar Keratoderma is a genetic disorder that cannot be prevented. However, the following may be considered:

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders such as hereditary palmoplantar keratoderma

What is the Prognosis of Diffuse Hereditary Palmoplantar Keratoderma? (Outcomes/Resolutions)

• The prognosis of Diffuse Hereditary Palmoplantar Keratoderma may depend on a set of several factors including:
  • Underlying disorder and the severity of the signs and symptoms
  • Response to therapy of the underlying cause of keratoderma
• Even though the skin condition (keratoderma) is benign, the overall prognosis is based on the underlying condition and can be established only on a case-by-case basis
• However, since hereditary palmoplantar keratoderma is genetic, the disorder persists the lifetime of the individual
• Regular follow up visits with the healthcare providers are important

Additional and Relevant Useful Information for Diffuse Hereditary Palmoplantar Keratoderma:

Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken avoid strong soaps and chemicals that could potentially worsen the condition.