Definition: is a skin rash caused by the immune system.
The condition usually goes away on its own within several weeks or months. There are also treatments that can improve symptoms. Lichen planus can be uncomfortable, however it is not considered dangerous.
It is not known why the immune response occurs. There may be several contributing factors, and each case is different.
Potential causes include:
- Viral infections
Sometimes, lichen planus occurs along with autoimmune disorders. Although it can be uncomfortable, in most cases lichen planus is not a serious condition. It is not contagious either.
However, there are some rare variations of the condition that can be serious and painful. It can be treated with topical and oral medications to reduce symptoms, or by using medications that suppress the immune system.
Symptoms of lichen planus
Some of the most common symptoms of lichen planus are the following:
- Purple lesions or protuberances with flat top on the skin or genitals.
- Injuries that develop and spread over the body for weeks or some months.
- Itching at the site of the rash.
- White lesions in the mouth, which can be painful or cause a burning sensation.
- Blisters, which explode and become scary.
- Fine white lines on the eruption.
The most common type of lichen planus affects the skin. Lesions and their spread appear over several weeks.
The condition will usually be clarified within six to 16 months. Less commonly injuries can occur in other areas besides the skin or genitals.
These may include:
- Mucous membranes.
- The scalp
- There are also variations of the most common condition in the Middle East, Asia, Africa and Latin America.
What are the causes and risk factors?
Lichen planus develops when the body mistakenly attacks its skin or cells of the mucous membrane. Doctors are not sure why this happens.
Lichen planus can occur in anyone at any age, but there are certain factors that make some people more likely to develop the disease.
Lichen planus occurs in men and women alike, but women are twice as likely to get the oral form. It is very rare in children and older adults. It is more common in middle-aged people.
Other risk factors include having family members who have had lichen planus, having a viral illness such as hepatitis C, or being exposed to certain chemicals that act as allergens.
These allergens can include:
- Iodide compounds.
- Certain types of dyes.
Diagnosis of lichen planus
Whenever you see or feel a rash on your skin or injury to your mouth or genitals, you should consult your doctor as soon as possible.
Your primary care doctor can send you to a dermatologist if the diagnosis of lichen planus is not obvious, or if your symptoms are making you feel very uncomfortable.
Your primary care physician or dermatologist may be able to tell you that you have lichen planus simply by looking at your rash. To confirm the diagnosis, you may need more tests.
Tests may include a biopsy, which means taking a small sample of your skin cells to be looked at under a microscope, or an allergy test to find out if you are having an allergic reaction.
If your doctor suspects that the underlying cause is an infection, you may need to have a test for hepatitis C.
The direct immunofluorescence study reveals globular deposits of immunoglobulin M (IgM) and complement mixed with apoptotic keratinocytes. No imaging studies are necessary.
The distinctive histopathological characteristics of lichen planus are the following:
Hyperkeratotic epidermis with irregular acanthosis and focal thickening in the granular layer.
Degenerative keratinocytes (colloid or civatte bodies) in the lower epidermis; In addition to apoptotic keratinocytes, colloidal bodies are composed of globular deposits of IgM (occasionally immunoglobulin G [IgG] or immunoglobulin A [IgA]) and complement.
Linear or furry deposits of fibrin and fibrinogen in the area of the basement membrane
In the upper dermis, an infiltrate in the form of a band of lymphocytes (mainly helper T) and histiocytic cells with many Langerhans cells.
Treatment of lichen planus
For mild cases of lichen planus, which usually clear up in weeks or months, you may not need any treatment. If the symptoms are uncomfortable or severe, your doctor may prescribe medications.
There is no cure for lichen planus, but medications that treat symptoms are helpful and some may even be able to guide a possible underlying cause.
Medications that are prescribed often include:
Retinoids, which are related to vitamin A and are taken topically or orally.
Corticosteroids reduce inflammation and can be topical, oral or administered as an injection.
Antihistamines reduce inflammation and can be particularly useful if the rash is caused by an allergen.
Nonsteroidal creams are applied topically and can suppress your immune system and help clear up the rash.
There are other things you can try at home to supplement your prescription treatments.
- Soaking in an oatmeal bath.
- Avoiding scratching
- Apply fresh compresses on the rash.
- Using OTC anti-itch creams.
Talk to your doctor before adding OTC products to your treatment plan. This way you will be sure that nothing you can take will interact with the prescription medications you are taking.
What are the complications of this disease?
Lichen planus can be difficult to treat if it develops in the vagina or vulva. This can cause pain, scars and discomfort during sex.
The development of lichen planus can also increase your risk of squamous cell carcinoma.
The increase in risk is small, but you should see your doctor for routine skin cancer exams.