Lichus planus is a condition that occurs when the body's immune system attacks the skin. The ensuing rash of raised, flat topped bumps often takes on a purple hue. The cause of lichen planus isn't known, but doctors believe it has something to do with the immune system; certain risk factors can trigger the rash.
Definition & Facts
Only about two percent of the population is affected by lichen planus. Most of those affected are middle aged women. The rash usually resolves on its own within two years. Lichen planus spreads and peaks within a few months and will slowly heal. However, it can reoccur. The lesions of lichen planus can appear anywhere on the skin or on mucous membranes.
Symptoms & Complaints
The bumps appear and then spread over the course of a few weeks to a few months. Only a small number of lesions may appear or some people may end up with lots of widespread lesions. Some bumps can also heal and new bumps develop on the same area.
If a lot of bumps keep developing on the same area, the skin can become thick, rough, and scaly. Rashes are itchy, and can become painful with repeated scratching. Rarely, blisters may develop around the site of the rash.
It's believed that this condition is an autoimmune disease, and that the body mistakes the skin cells as foreign and starts attacking them. There is no known exact cause of lichen planus, but it does have a number of associated risk factors. Women are more likely than men to get lichen planus, and it seems to be associated with stress and depression.
Some medications may increase the chances of triggering this condition, such as diuretics and medications used to treat or prevent heart disease, high blood pressure, arthritis, and malaria. People with certain medical conditions, including autoimmune disorders, may also develop these diseases. Those conditions associated with developing lichen planus are:
- Liver disease
- Graft-versus-host disease
- Primary sclerosing cholangitis
- Lupus erythematosis
- Primary biliary cirrhosis
- Sjogren’s syndrome
- Ulcerative colitis
- Alopecia areata
- Masthenia gravis
An allergic reaction can also lead to the development of lichen planus. A food, food additive, dye, fragrance, or even dental metal reaction can turn into a flare-up. It's possible, though rare, for lichen planus of the mouth to develop as a reaction to a metal filling. Chewing on betel quid nuts or the plant can increase a person's risk too.
Diagnosis & Tests
It is important to go to the doctor, ideally a dermatologist, for a diagnosis of lichen planus. Those who visit their general practitioner may be referred to a dermatologist for diagnosis. This is more likely if the lesions are not obvious or if the symptoms experienced by the patient are moderate to severe.
Patients complaining of extreme pain, swelling, or widespread lesions may need to have other conditions ruled out by the dermatologist. Most doctors diagnose the condition just by looking at the characteristic purplish lesions on the skin, nails, or in the mouth.
It's not uncommon for the doctor to also find signs of lichen planus in the mouth during a visit for lichen planus on the skin. The doctor may also take a skin biopsy which is a small sample of skin tissue and look at it under a microscope. If the doctor is concerned about the rash being the result of another condition, he or she may take a blood sample to perform a blood test. The sample should be tested for other diseases that lead to similar rashes.
Treatment & Therapy
There is no cure for lichen planus. The condition is known to resolve itself within two years, though some people may have it reoccur periodically for years afterwards. However, mild cases may even clear up in a few months. Treatment is usually to allow the condition to run its course, unless the patient is in discomfort.
Doctors can prescribe medication that will help relieve itching and pain, and may help speed healing. An antihistamine is helpful for the itching and inflammation that may be a result of an allergic reaction. A topical corticosteroid is used to help reduce the inflammation and redness of a lesion.
Patients may also get oral corticosteriods or injections for widespread rashes. Non-steroidal creams help suppress the immune system, which can reduce the appearance of the rash and allow skin to clear faster. A retinoid cream contains a form of vitamin A and can also help clear the rash.
Some types of Lichen Planus respond well to ultraviolet light treatments such as PUVA therapy. The doctor might also try tacrolimus ointment or pimecrolimus cream, which is used to treat eczema. These are non-steroidal creams with anti-inflammatory properties and may have some immune-modulating effects.
Prevention & Prophylaxis
Those with lichen planus of the mouth should keep up with regular brushing and flossing in order to avoid gum disease. It is prudent to visit the dentist at least twice a year to get an exam and a dental cleaning.