Darier disease: symptoms, causes, treatment and living with it

Darier disease is also known as Darier-White disease and keratosis follicularis. BAD describes it as a rare inherited skin condition characterised by a change in the way skin cells (keratinocytes) stick together within the upper layer of the skin. Normally these cells are held together like bricks cemented in a wall. In Darier disease the cement is weakened, so the cells separate easily and do not form a good barrier against the outside world.

The result is skin that becomes easily irritated and inflamed and may weep. The Primary Care Dermatology Society (PCDS) describes it as a rare, chronic, autosomal dominant condition that usually arises in adolescence and is characterised by scaly papules, most often on the upper trunk.

The PCDS says the gene involved has been identified as ATP2A2 on chromosome 12, and that a fault in it affects desmosome function, which reduces cell-to-cell adhesion. BAD explains that the movement of calcium within cells is disrupted.

The condition is inherited in a dominant pattern, so there is a 1 in 2 chance that each child of an affected parent will inherit it. It affects men and women equally and often begins in childhood. BAD notes that some people inherit the genetic change but do not develop skin problems, that severity can vary considerably within a family, and that sometimes there is no family history, either because it is so mild in a parent that it went unnoticed or because the change arose for the first time in the individual. A clinical genetics service can discuss family planning.

BAD says the rash usually appears in childhood or the teenage years, though in some people it is not present until adulthood. It mainly affects areas rich in sebaceous glands, typically the face, scalp, chest, neck and upper back. The appearance varies from small, slightly greasy or waxy brownish, yellowish or red lumps to larger, thickened patches that may be crusty or scaly. In skin folds such as the groin and under the breasts, the skin may become raw and weep.

• Red or white lines running along the fingernails, with small notches at the ends of the nails.

• Pits or small areas of hard skin on the palms and, less often, the soles.

• Flat, wart-like bumps on the backs of the hands, which BAD says can appear in children several years before other skin changes.

• Small spots inside the mouth that may make the roof of the mouth feel rough.

• Itching, soreness and an unpleasant odour in moist areas such as the underarms and groin, caused by skin bacteria.

BAD lists heat, sunlight, friction, excessive sweating and certain prescribed medicines taken by mouth as things that can make the rash worse. The PCDS notes that extensive, malodorous and painful skin can affect social life, work or school.

People with Darier disease are more likely to develop bacterial, fungal and viral skin infections, and these can trigger flares. BAD highlights the risk of widespread herpes simplex infection. If the skin suddenly gets much worse and is more painful than usual, this may indicate herpes simplex even without the usual blisters, and urgent medical advice should be sought. The PCDS adds that severe infections may be disseminated and, rarely, fatal, which is why early treatment with antiviral medicines matters.

The PCDS also reports that neuropsychiatric features such as depression, bipolar disorder, epilepsy and intellectual difficulties have been described in some people with the condition. Mood and wellbeing are therefore a legitimate part of the discussion with a doctor.

BAD says the diagnosis can often be made from the appearance of the rash and the fact that it runs in families. To confirm it, a dermatologist may take a small skin sample (biopsy) to be examined under a microscope. The PCDS says it is usually diagnosed clinically, with a biopsy occasionally required.

In practice a GP who suspects Darier disease will usually refer to a dermatologist, especially if the skin is widespread, painful or repeatedly infected.

BAD says that if there are no symptoms, treatment is not required, and that simple measures such as cotton clothing, minimising sweating and sun protection may reduce symptoms. There is no cure, but there are many ways of managing the skin, and the condition can recur after treatment.

BAD says most people with Darier disease lead a normal life and have no other medical problems. It recommends monitoring your skin regularly and reporting changes or concerns to your GP or dermatologist.

Practical steps include choosing loose, breathable clothing, keeping skin folds clean and dry, using high-factor sun protection and avoiding unnecessary overheating. Anyone taking oral retinoids who might become pregnant needs specialist contraception advice, because these medicines must not be used in pregnancy.

On the NHS, a GP can start emollients and treat infections, and refers to a dermatology department for confirmation, specialist treatment and sometimes genetic counselling. The PCDS recommends referral for more severe disease.

A private consultant dermatologist can offer an earlier appointment or a second opinion. Because Darier disease is rare, it can be sensible to ask whether the clinician has experience of genetic skin conditions, and some people are seen through specialist centres.