Table of Contents
Definition of Lichen Planus
Lichen Planus – a common condition affecting the SKIN that appears as small, shiny, reddish purple (violaceous) bumps that itch, sometimes intensely. The bumps grow together in a scalelike pattern that resembles tree lichen. Lichen planus nearly always occurs in adults.
Symptoms and Diagnostic Path
Lichen planus typically erupts on the inner surfaces of the lower arms and wrists, along the shins and inner ankles, and along the lower back.
Occasionally appears on the scalp, where it can cause temporary or permanent ALOPECIA (hair loss), or affects the fingernails and toenails, causing ridges and grooves.
In the MOUTH, lichen planus is light in color and the scaling more diffuse, creating a lacelike pattern lighter in color than the surrounding mucosa. The distinctive color and pattern of the RASH allow the dermatologist to make a quick diagnosis. The doctor may biopsy lichen planus lesions that appear in the mouth, as they resemble other conditions (such as CANDIDIASIS and precancerous lesions) that require different treatment.
Treatment Options and Outlook
Outbreaks of lichen planus typically retreat without medical intervention, though ANTIHISTAMINE MEDICATIONS and topical CORTICOSTEROID MEDICATIONS can help relieve the itching. In severe cases, the dermatologist may prescribe oral corticosteroids such as prednisone to suppress the IMMUNE RESPONSE. An outbreak may last several weeks to several months and typically flares in irregular recurrences over a period of years. Gentle, regular skin cleansing and moisturizing can help to manage and reduce symptoms.
Risk Factors and Preventive Measures
Dermatologists do not know what causes lichen planus, though believe it is an immune response of some sort, either an autoimmune condition or an immune response to a VIRUS, likely with a genetic predisposition.
Lichen planus also occurs in HEPATITIS C INFECTION, is an early sign of transplant organ rejection, and is a rare SIDE EFFECT of some medications such as long-term therapy with the antimalarial medication quinidine and some NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) used for OSTEOARTHRITIS.
Avoiding exposure to substances that can cause lichen planus, when identified, usually prevents future outbreaks though some people continue to experience cycles of the condition for several years.