What is lichen planus ?
It is an inflammatory condition of the skin.
What is the chance of having it ?
At any time, the frequency is evaluated at 0.5% of the population
The development of lesions is triggered by stress.
What does it look like ?
It is characterized by violet bumps on the skin. These bumps have a flattened surface and are covered by fine whitish lacy network. However, the lesions can have a different appearance.
Lesions are typically localized on the anterior aspects of the wrists, the lower limbs, the lumbar region, and the mucosal areas (oral, genital). They can also be on the areas of previous trauma (Koebner (Köbner, Kobner)) phenomenon and can be very itchy.
Oral Lichen Planus
Why do I have it ?
The exact cause is unknown. An autoimmune cause would be the most likely (similar lesions develop in graft versus host disease and lupus erythematosus).
An association with chronic liver disease and hepatitis C exists.
Will it go away ?
Most frequently the lesions disappear within 12-15 months.
Recurrences are seen in 15-50% of cases even after many years.
There are long lasting types which induce scarring and carry an increased risk of skin cancer.
What is the treatment ?
Steroids administered in creams,orally and intralesionally.
Other oral treatments and light therapy are sometimes used.
Bibliography: Dermatologie et infections sexuellement transmissibles (French), 5th edition