Lichen Planus

Lichen Planus – Disease of the Skin 

Lichen planus is a disease of the skin, a chronic recurrent rash which is caused due to inflammation. The rash is characterized by small, flat topped with many sided bumps which tend to grow together into rough, scaly plaques on the skin. It resembles lichen that grows on tree bark or on rocks.

The cause of this disease is not known though it is presumed to be the result of an autoimmune process with an unknown trigger. There is no cure though various medications and procedures can be used in order to control the symptoms. Lichenoid reaction or lichenoid lesion is referred to a lesion of identical or similar histopathologic and clinical appearance to lichen planus which is an area that seems the same as lichen planus to the naked eye as well as under a microscope.

At times dental materials or some medication could cause lichenoid reaction. Besides this it could also occur in association with graft versus host disease. Lichen planus can be distinguished from psoriasis, eczema and other rashes on the basis of its clinical appearance wherein the lesions are small bumps or aggregations of bumps which are flat, topped, polygonal, shiny, and purple to grey in colour and may tend to appear at the wrist, elbows and ankles. On observing closely, it may have thin white lines known as Wickham’s striae.

Symptoms 

Lichen planus tend to itch with an intensity which may vary in different cases from mild to severe. Its onset could be sudden or gradual and the first attack could last for weeks or months with recurrences that may take place for years.

 The bumps in its initial stage are 2mm to 4mm in diameter with angular borders together with a violet colour. Excess of pigment – hyperpigmentation, may tend to develop in the affected area as the lesions persist. In rare cases, a patchy, scarring balding appears on the scalp.

Skin involvement with lichen planus comprises of flat topped lilac or violet spots of a few millimetres in diameter on the skin which appear in areas of the wrists, forearms, lower legs above the ankles as well as the lower part of the back. Variant of this disease is known as hypertrophic lichen planus. In this condition a thick, reddish brown lesion appears which are covered with scales.

These spots appear to be on the skin though they could occur on any area of the body and are itchy with persistent variant of lichen planus.

Treatment

Dentists often come across a white lacy rash on the inside of the cheeks of people who may not be aware of this condition and are affected with lichen planus. They tend to have the rash inside their mouth – oral mucosa. This rash often appears prior to any skin involvement. Rare but more troublesome is erosive lichen planus which could be quite sore and uncomfortable causing the person to complain of the shallow and painfully recurrent ulcers in the mouth.

Lichen planus could also affect the female genitals.Most cases of lichen planus of the skin disappears on their own within six to nine months and the rash rarely last longer than eighteen months. If the itch or the appearance of the rash is unpleasant, topical corticosteroid creams could be helpful. In more severe cases, physician may recommend oral medications or therapy with ultraviolet light.