LICHEN PLANUS Dr. Angelo Smith

WHPL

Overview

Lichen planus has been described as an autoimmune disease,   a dermatosis,  a papulosquamous disorder, a mucocutaneous disease,  and an inflammatory disease.

Lichen planus lesions are so called because of their "lichen-like" appearance

Cause The cause of lichen planus is not known; however,

there are cases of lichen planus - type rashes (known as lichenoid reactions) occurring as

allergic reactions to medications for high blood pressure, heart disease and arthritis.

These lichenoid reactions are referred to as lichenoid mucositis (of the mucosa) or dermatitis (of the skin).

Lichen planus has been reported as a complication of chronic hepatitis c virus infection and can be a sign of chronic graft-versus-host disease of the skin.

It has been suggested that true lichen planus may respond to stress, where lesions may present on the mucosa or skin during times of stress in those with the disease.

Lichen planus affects women more than men (at a ratio of 3:2), and occurs most often in middle-aged adults.

Lichen planus in children is rare.

C/P The typical rash of lichen planus is

well-described by the "5 P's": well-defined pruritic, planar, purple, Polygonal, papules

Flexor surfaces especially wrists, flanks, medial thighs, shins of tibia, glans penis, nails, scalp & oral mucosa.

Pruritus; rubbing than scratching.

Koebner’s phenomenon (isomorphic response).

After lesions subside, post lichen hyperpigmentation occurs.

Koebner's Phenomenon

Hypertrophic Lp

•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.

Lichen planopilaris

Lichen Planopilaris is the specific name given to lichen planus on the scalp that may cause permanent, scarring alopecia

Oral LP Oral lichen planus may present in one of three

forms. The reticular form is the most common

presentation and manifests as white lacy streaks on the mucosa (known as Wickham's striae) or as smaller papules (small raised area). The lesions tend to be bilateral and are asymptomatic. The lacy streaks may also be seen on other parts of

the mouth, including the gingiva (gums), the tongue, palate and lips.

The bullous form presents as fluid-filled vesicles which project from the surface

The erosive form presents with erythematous (red) areas that are ulcerated and uncomfortable.

The erosion of the thin epithelium may occur in multiple areas of the mouth, or in one area, such as the gums, where they resemble desquamative gingivitis.

Wickham's striae may also be seen near these ulcerated areas. This form may undergo malignant

transformation.

LP of oral mucosa

LP of the Tongue

Complications of LP

Squamous cell carcinoma in oral ulcerative lesions.

Cicatricial alopecia in scalp LP.

Post inflammatory hyper pigmentation.

Differential Diagnosis The clinical presentation of lichen planus may

also resemble other conditions, including: Lichenoid drug reaction Discoid Lupus Erythematosus Chronic Ulcerative Stomatitis Pemphigus Vulgaris Benign Mucous Membrane Pemphigoid Oral leukoplakia Frictional keratosis

A biopsy is useful in identifying histological features that help differentiate lichen planus from these conditions.

Course and Outcome Currently there is no cure for lichen planus but

there are certain types of medicines used to reduce the effects of the inflammation.

Lichen planus may go into a dormant state after treatment.

There are also reports that lichen planus can flare up years after it is considered cured.

Medicines used to treat lichen planus include: Oral and topical steroid Oral retinoids immunosuppressant medications Hydroxychloroquin Tacrolimus dapson