Lichen-Planus(लाइकेन प्लानस) is a chronic recurrent skin disease of unknown cause with no established cure. Lichen planus generally affects adults and can involve any portion of the skin and lining tissue (mucous membranes) of the mouth and/or vagina, but it has a predilection for the wrists, ankles, and oral and genital tissues.
Lichen planus is a chronic recurrent inflammatory disorder of the skin and mucous membranes. It is characterized by small, flat-topped, polygonal bumps that may coalesce into rough, scaly plaques on the skin. There may also be involvement of the lining tissue (mucous membranes) of the mouth and/or vagina.
Lichen planus is a poorly understood skin condition. Its name is descriptive in that to some it resembles a simple plant, a lichen, which grows on rocks and tree bark, while planus is Latin for flat.
What does lichen planus look like?
The appearance of lichen planus depends on whether the skin or the lining (mucous membranes) inside the mouth or vagina are affected:
- Skin involvement: The usual skin involvement with lichen planus consists of flat-topped lilac or violet to brown spots a few millimeters in diameter on the skin. These spots tend to be located on the inner wrists, forearms, the lower legs just above the ankles, and the lower part of the back.
- A variant of this disease is called hypertrophic lichen planus. This condition appears as thick, reddish-brown lesions that are covered with scales. These spots tend to be on the shins, but they can occur anywhere on the body. This is an especially itchy and persistent (chronic) variant of lichen planus.
- Atrophic lichen planus produces slightly depressed lesions that otherwise resemble typical lichen planus.
- Mucous membranes: Lichen planus of the mucous membranes of the mouth and genitals is common. It appears as a white, lacy rash on the inside of the cheeks or the vagina and may not cause symptoms. The oral rash often occurs prior to any skin involvement. More troublesome, although rare, is erosive lichen planus, which can be quite sore and uncomfortable. This erosive form typically causes the patient to complain of the shallow and often quite painful, recurrent ulcers in the mouth or genitals. Lichen planus of the female genitalia can involve the external vulvar mucosa and the internal vaginal mucosa. There is an association with cancer in these areas, so both the oral and vaginal tissues need to monitored by a medical professional.
- Nail malformation may be produced by lichen planus.
- Lichen planus may involve the scalp, producing a permanent, scarring type of balding.