Lichen planus

February 3, 2017

Lichen planus is an inflammatory skin condition, characterized by an itchy, non-infectious rash of small, polygonal (many sided) flat-topped pink or purple lesions (bumps) on the arms and legs. Other parts of the body may also be affected, including the mouth, nails, scalp, vulva, vagina, and penis. Involvement in the scalp can result in hair loss – sometimes permanent.

Doctors use the word ‘lichen’ to mean small bumps on the skin. ‘Planus’ means ‘flat’, and tells us that the small itchy bumps that make up the rash of lichen planus have shiny flat tops. These bumps have a reddish-purplish color with a shiny cast due to a very fine scale. The disease can occur anywhere on the skin, but often favors the inside of the wrists and ankles, the lower legs, back, and neck. The mouth, genital region, hair and nails are affected in some individuals. Thick patches may occur, especially on the shins. Blisters may rarely occur. Bumps may appear in areas of trauma on some individuals. About 20 percent of the time lichen planus of the skin causes minimal symptoms and needs no treatment. However, in many cases the itching can be constant and intense.

This disease occurs most often in men and women between the ages of 30 and 70 years. It is uncommon in the very young and elderly. All racial groups seem susceptible to lichen planus.

Lichen planus is not contagious. Lichen planus is not a type of cancer.

Causes

What causes most cases of lichen planus remains unclear. One theory is that lichen planus is an autoimmune disease. This means the person’s immune system reacts as though the skin and other parts of the body are foreign. When this happens, the body starts to attack itself. To find out whether lichen planus is an autoimmune disease.

Others –

Some medicines can cause a rash that looks like lichen planus. These medicines include diuretics (treatment for high blood pressure and heart disease) and medicine taken to prevent malaria.
In the mouth, a metal filling may be the cause. This is rare, but it can happen. If this is the cause, replacing the metal filling with a non-metal filling will get rid of the lichen planus.
A rare type of lichen planus, familial bullous lichen planus, runs in families. Other forms of lichen planus do not seem to run in families.
There may be a link between lichen planus and infection with the hepatitis C virus. Many people with hepatitis C also have lichen planus.

Risk Factors

About one in 100 people will get lichen planus at some time. It is not caused by an infection, and people can’t pass it on to others. Lichen planus usually affects men and women in middle age. Equal numbers of men and women get lichen planus of the skin, but women are twice as likely to get oral (inside the mouth) lichen planus. The disease is rare in people who are very young or very old.

Symptoms

Mouth sores are one symptom of lichen planus. They –

May be tender or painful (mild cases may not cause pain)
Are located on the sides of the tongue, inside of the cheek, or on the gums
Look like bluish-white spots or pimples
Form lines in a lacy network
Gradually increase in size
Sometimes form painful ulcers

Skin sores are another symptom of lichen planus. They –

Usually appear on the inner wrist, legs, torso, or genitals
Are itchy
Have even sides (symmetrical) and sharp borders
Occur alone or in clusters, often at the site of a skin injury
May be covered with thin white streaks or scratch marks
Are shiny or scaly looking
Have a dark, reddish-purple color
May develop blisters or ulcers

Other symptoms of lichen planus are –

Dry mouth
Hair loss
Metallic taste in the mouth
Ridges in the nails

Complications

After the rash has gone there may be permanent brown or grey marks on the skin – the darker the patient’s skin is the more noticeable they will be.

Persistent skin lesions and mouth ulcers may slightly raise the risk of developing cancer (rare).

Treatment

The goal of treatment is to reduce symptoms and speed healing. If your symptoms are mild, patients may not need treatment.

Treatments may include –

Antihistamines
Medicines that calm down the immune system (in severe cases)
Lidocaine mouthwashes to numb the area and make eating more comfortable (for mouth sores)
Topical corticosteroids or oral corticosteroids to reduce swelling and lower immune responses
Corticosteroid shots into a sore
Vitamin A as a cream or taken by mouth
Other medicines that are applied to the skin
Dressings placed over your skin with medicines to keep you from scratching
Ultraviolet light therapy

Alternative Treatment

Purported alternative treatments for lichen planus of the skin include: