Darier Disease (Keratosis Follicularis)

What causes Darier disease

The ATP2A2 gene makes SERCA2, a pump that moves calcium inside skin cells. Calcium is needed to build the desmosomes, the "rivets" that hold skin cells together. With faulty SERCA2, skin cells separate (acantholysis) and form abnormal keratin, producing the characteristic bumps.

It is inherited in an autosomal dominant pattern: an affected parent has a 50 percent chance of passing it to each child. About half of cases arise from a new gene change with no family history. Severity varies widely, even within families.

Symptoms

Skin

• small, firm, skin-colored to brown, rough or greasy bumps (papules), often crusted
• typical areas: central chest, upper back, neck, scalp, forehead, behind the ears, groin and armpits ("seborrheic" areas and skin folds)
• bumps may join into warty plaques, especially in folds
• itching, which can be intense
• a strong odor from bacteria and yeast on the crusts
• small pits or keratotic bumps on the palms and soles
• flat, wart-like bumps on the backs of the hands (acrokeratosis verruciformis)

Nails

Nail changes are very characteristic and help diagnosis:

• red and white lengthwise streaks
• V-shaped notches at the free edge
• thickening under the nail and brittleness

Mouth

White, cobblestone-like bumps on the palate or gums in some people.

Linked conditions

People with Darier disease have higher rates of depression, bipolar disorder and epilepsy, and occasionally learning difficulties. The same gene is active in the brain, which may explain this link.

Triggers and patterns

• heat and humidity, and sweating
• sunburn and ultraviolet light
• friction from clothing
• emotional stress
• lithium and some other medicines
• infections

Most people notice summer flares. Some have a segmental form, with bumps only along a band or line of skin, caused by a gene change in only some skin cells.

Diagnosis

A dermatologist often suspects Darier disease from the appearance and distribution of the rash and the nail changes. A skin biopsy confirms it by showing separation of skin cells with abnormal keratinization. Genetic testing of ATP2A2 can confirm the diagnosis and help with family planning.

Conditions that can look similar include seborrheic dermatitis, Hailey-Hailey disease, Grover disease, acne and warts.

Treatment

Everyday care

• Keep cool; avoid overheating, hot baths and heavy exercise in hot weather.
• Wear loose, breathable cotton clothes.
• Use high-SPF sunscreen and sun-protective clothing.
• Use emollients and soap substitutes; urea or lactic acid creams soften rough bumps.
• Antiseptic washes, such as chlorhexidine or dilute bleach baths if advised, reduce bacteria and odor.

Medicines

• Topical retinoids (adapalene, tazarotene, tretinoin) for limited areas; they can irritate.
• Topical steroids for short periods to calm inflammation and itch, often combined with an antiseptic or antibiotic.
• Oral retinoids (acitretin or isotretinoin) for widespread or severe disease; they are the most effective treatment. They cause serious birth defects, so strict pregnancy prevention is required, and acitretin requires avoiding pregnancy for several years after stopping. Blood tests monitor liver function and lipids.
• Antibiotics or antivirals for infections.
• Other options for resistant areas include laser treatment, photodynamic therapy and surgery, and, in research settings, other medicines.

Infections

Eczema herpeticum, a widespread herpes simplex infection of affected skin, is a recognized complication and needs urgent antiviral treatment. See herpes simplex. Bacterial infections are common and need antibiotics.

Living with Darier disease

The condition is lifelong, usually with periods of flares and improvement. It can affect confidence, relationships and work, particularly because of visible skin changes and odor. Dermatology follow-up, mental health support where needed, genetic counseling and patient support groups all help.

Frequently asked questions

What causes Darier disease?

It is caused by a change in the ATP2A2 gene, which affects calcium handling in skin cells and weakens the connections between them. It is inherited in an autosomal dominant pattern, but about half of cases arise from a new gene change without a family history.

Is Darier disease contagious?

No. Darier disease is genetic and cannot spread from person to person. However, the affected skin is prone to bacterial, fungal and herpes infections, and these infections can be contagious.

What does Darier disease look like?

It causes small, rough, greasy, brownish bumps, often crusted, on the chest, back, neck, scalp, forehead and skin folds. Nails show red and white streaks with V-shaped notches. The rash often smells unpleasant and flares in hot weather.

Can Darier disease be cured?

There is no cure, but it can be controlled. Avoiding heat, sweat and sun, using emollients and antiseptics, and taking topical or oral retinoids reduce flares. Treating infections quickly prevents complications. Severity often varies over a lifetime.