Keratoderma
Abnormal thickening of the skin on the palms and soles
Quick Facts
- Type: Skin condition (keratinization disorder)
- Main sites: Palms of the hands, soles of the feet
- Forms: Inherited and acquired
- Key feature: Thick, often yellow, hardened skin
Overview
Keratoderma refers to marked thickening of the skin, most often on the palms of the hands and the soles of the feet, where it is called palmoplantar keratoderma. The skin builds up extra keratin, the tough protein that forms the surface layer, leaving the palms and soles thick, hard, and sometimes yellow or cracked.
Keratoderma comes in two broad types. Inherited (hereditary) keratoderma is present from birth or early childhood and runs in families. Acquired keratoderma develops later in life and may be linked to skin disease, friction, infection, medications, or underlying medical conditions. The two types are managed differently, so working out which one is present is important.
Symptoms
The defining feature is thickened, hardened skin on the palms and soles, but the exact appearance varies by type.
- Diffuse, even thickening across the whole palm or sole
- Localized thick spots or bands, often over pressure points
- Small, scattered thickened bumps (a punctate pattern)
- Yellowish discoloration of the affected skin
- Deep, sometimes painful cracks (fissures)
- Excess sweating or a distinct odor in some forms
Severe thickening can make walking uncomfortable, reduce grip, and limit fine hand movements. Cracks can be painful and may become infected.
Causes
Keratoderma results from the skin producing too much keratin on the palms and soles. The reasons differ between the inherited and acquired forms:
- Inherited keratoderma: Caused by gene changes affecting how skin cells mature and stick together; these run in families and appear early in life.
- Skin diseases: Eczema, psoriasis, and certain other conditions can thicken the palms and soles.
- Friction and pressure: Heavy manual work or ill-fitting footwear can drive thickening.
- Infections: Some fungal and other infections affect the soles.
- Medical conditions and medications: Thyroid problems, certain internal conditions, and some drugs are associated with acquired keratoderma.
A sudden, new acquired keratoderma in an adult sometimes prompts a search for an underlying internal cause.
Risk Factors
- A family history of thickened palms and soles
- Chronic skin conditions such as eczema or psoriasis
- Occupations or activities involving repeated friction
- Certain hormonal or internal medical conditions
- Use of medications known to affect skin keratinization
Diagnosis
A dermatologist usually makes the diagnosis from the appearance and pattern, then determines the type:
- Skin examination: The distribution and pattern (diffuse, focal, or punctate) give important clues.
- Family and medical history: Early onset and affected relatives suggest an inherited form; later onset suggests an acquired cause.
- Skin biopsy: A small sample can clarify the diagnosis.
- Further tests: When an acquired form appears suddenly, blood tests or other investigations may look for an underlying condition.
Treatment
There is no cure for the inherited forms, but symptoms can be reduced and acquired forms often improve when the cause is treated.
- Softening creams: Emollients and keratin-dissolving agents containing urea, salicylic acid, or lactic acid help thin the skin.
- Soaking and paring: Soaking followed by careful filing or professional paring reduces thick buildup.
- Treating the cause: For acquired keratoderma, addressing the underlying skin disease, infection, or medical condition often helps.
- Oral retinoids: For severe inherited forms, a specialist may prescribe vitamin A-derived medicines.
- Footwear and padding: Cushioning and well-fitting shoes ease pressure and reduce painful cracking.
Prevention
- Moisturize palms and soles regularly to keep skin supple and reduce cracking
- Wear well-fitting, cushioned footwear
- Protect hands with gloves during repetitive or rough work
- Treat underlying skin conditions and infections promptly
- Keep deep cracks clean to prevent infection
When to See a Doctor
See a doctor or dermatologist if the skin on your palms or soles becomes thick, painful, or develops deep cracks, or if a new thickening appears in adulthood without an obvious cause. Seek prompt care if cracked skin shows signs of infection such as spreading redness, warmth, swelling, or pus. People with a family history of keratoderma may benefit from specialist and, in some cases, genetic advice.
Frequently Asked Questions
What is the difference between inherited and acquired keratoderma?
Inherited keratoderma is caused by gene changes, runs in families, and usually appears in infancy or childhood. Acquired keratoderma develops later in life and is linked to skin disease, friction, infection, medications, or internal conditions. Acquired forms often improve when the underlying cause is treated.
Can keratoderma be cured?
Inherited forms cannot be cured, but symptoms are managed long-term with softening creams, careful skin care, and sometimes oral retinoids for severe cases. Acquired forms can resolve or improve when the condition causing them is identified and treated.
Is keratoderma painful?
It can be. Thick skin over pressure points and deep cracks on the soles can make walking and gripping uncomfortable. Regular moisturizing, keratin-softening creams, and cushioned footwear help reduce pain and cracking.
Should new thickening of the palms and soles in an adult be checked?
Yes. A new, unexplained keratoderma in adulthood sometimes signals an underlying medical condition or a reaction to medication, so it is worth having a doctor evaluate it. A dermatologist can examine the pattern and arrange any needed tests.
References
- DermNet. Keratoderma.
- MedlinePlus, U.S. National Library of Medicine. Skin thickening.
- American Academy of Dermatology Association. Dry skin and keratinization disorders.
- Genetic and Rare Diseases Information Center (GARD). Palmoplantar keratoderma.