Lichen planus

What is lichen planus?

Lichen planus is a chronic inflammatory skin condition that affects the skin and mucous membrane Surfaces There are several clinical types of lichen planus that share similar characteristics in histopathology.

• Cutaneous lichen planus
• Lichen planus of the mucosa
• Lichen planus
• Lichen planus of the nail
• Lichen planus pigmentosum
• Lichenoid drug eruption

Who gets lichen planus?

Lichen planus affects approximately one in one hundred people worldwide, mainly adults over 40 years of age. Approximately half of those affected have oral lichen planus, which is more common in women than in men. Around the 10% you have lichen planus nails.

What causes lichen planus?

Lichen planus is a T cell-mediate autoimmune disorder, in which inflammatory cells attack an unknown protein within the skin and mucosa keratinocytes.

Factors contributing to lichen planus may include:

• Genetic predisposition
• Physical and emotional stress.
• Skin lesion; Lichen planus often appears where the skin has been scratched or after surgery, this is called isomorphic answer (koebnerisation)
• Located skin disease like herpes zosterisotopic response
• Systemic viral infection, as hepatitis C (which could modifyantigens on the surface of basal keratinocytes)
• Contact allergy, such as metallic fillers in oral lichen planus (rare)

• Drugs; gold, quinine, quinidine and others can cause a lichenoid eruption.

A lichenoid inflammation also notable in grafting againsthost disease, a complication of the bone marrow transplant.

What are the clinical characteristics of lichen planus?

Lichen planus can cause a small amount or many lesions on the skin and mucosal surfaces.

Cutaneous lichen planus

The usual presentation of the disease is classic lichen planus. Symptoms can range from none (uncommon) to severe itching.

• Papules and polygonal plates They are shiny, flat-tipped and firm on palpation.
• The plates are crossed by fine white lines called Wickham striae.
• Hypertrophic lichen planus can be scaly.
• Atrophic lichen planus is a rare cancel variant with an atrophic center.
• Bullous Lichen planus is rare.
• The size varies from tip to larger than one centimeter.
• Distribution can be scattered, grouped, linear, ring or actinic (sites exposed to the sun such as the face, neck and back of the hands).
• The location can be anywhere, but most often in front of the wrists, lower back, and ankles.
• The color depends on the patient's skin type. The new papules and plaques often have a purple or purple hue, except on palms and soles, where they are yellowish-brown.
• The plates resolve after a few months to leave a grayish brown. post-inflammatory macules that may take a year or more to fade.

See more images of lichen planus.

Oral lichen planus

The mouth is often the only affected area. Oral lichen planus often involves the inside of the cheeks and the sides of the tongue, but the gums and lips may also be involved. The most common patterns are:

• Painless white stripes on a lace or fern pattern
• Painful and persistent erosions and ulcers (erosive lichen planus)
• Diffuse redness and peeling of the gums (desquamative gingivitis)
• Localized inflammation of the gums adjacent amalgam fillings.

Vulvar lichen planus

Lichen planus can affect the labia majora, labia minora, and vaginal introitus. The presentation includes:

• Painless white stripes on a lace or fern pattern
• Persistent and painful erosions and ulcers (erosive lichen planus)
• Scarring, which produces adhesions, reabsorption of the labia minora and introitals. stenosis
• Painful desquamative vaginitis, which prevents intercourse and causes a vaginal mucosa. download. The eroded vagina can easily bleed on contact
• Overlap with lichen vulvar sclerosus, an inflammatory skin disorder that most commonly affects women over 50.

Lichen planus of the penis

Lichen planus of the penis usually presents with classic papules in a ring around the glans. White streaks and erosive lichen planus may appear, but are less common.

Genital lichen planus images

Other mucosa sites

Erosive lichen planus infrequently affects lacrimal glands, eyelids, external ear canal, esophagus, larynx, bladder and anus.

Lichen planus

Lichen planopilaris appears as a small red hawthorn follicular papules on the scalp or less frequently, on other parts of the body. Rarely, blisters occur in the lesions. Destruction of the hair follicles leads to permanently bald patches characterized by few "lone hairs".

Frontal fibrosing alopecia It is a form of lichen planopilaris that affects the previous scalp, forehead and eyebrows.

Brocq's pseudopelade is probably a variant of lichen planus without inflammation or climbing. Hairless scar areas appear slowly, described as "like footprints in the snow."

Lichen planus nail

Lichen planus affects one or more nails, sometimes without affecting the surface of the skin. It's called twenty nails dystrophy if all nails are abnormal and no other place is affected. Lichen planus thins the nail plate, which can have striae and striae. The nail may darken, thicken, or rise from the nail bed (onycholysis) Sometimes the cuticle is destroyed and forms a scar (pterygium) Nails can come off or stop growing completely, and rarely disappear completely (anonychia).

See more images of lichen planus nails.

Lichen planus pigmentosum

Lichen planus pigmentosum describes poorly defined, grayish-brown oval marks on the face and neck or trunk and extremities without an inflammatory phase. It is a form of acquisition dermal macular hyperpigmentation. It can be caused by sun exposure, but it can also arise in places protected from the sun, such as the armpits. It has fuzzy, lattice, and fuzzy patterns. Pigmentary lichen planus is similar to erythema dyschromicum perstans and could be the same disease.

Lichen planus pigmentosum rarely affects the lips, resulting in a dark patch. pigmentation on the upper and lower lips.

Lichenoid drug rash

Lichenoid drug rash refers to a lichen planus-like rash caused by drugs. Asymptomatic or pink, brown, or purple itch; Flat, slightly scaly patches appear most frequently on the trunk. Oral mucous membrane (oral lichenoid reaction) and other sites are also sometimes affected. Many drugs can rarely cause lichenoid rashes. The most common are:

• Gold
• Hydroxychloroquine
• Captopril

Quinine and thiazide diuretics cause a photosensitive Lichenoid drug rash.

WhWhat are the complications of lichen planus?

Hypertrophic lichen planus may resemble scaly cell carcinoma. However, on rare occasions, long-standing erosive lichen planus can cause true squamous cell carcinoma, most often in the mouth (oral Cancer) or in thme vulva (cancer of the vulva) or penis (cancer of the penis). This should be suspected if there is an enlargement nodule or a ulcer with thickened edges at these sites. Cancer is more common in smokers, those with a history of cancer at mucosal sites, and those who have oncogenic human papilloma virus.

Cancer of other forms of lichen planus is rare.

How is lichen planus diagnosed?

In most cases, lichen planus is diagnosed by looking at its clinical features. A biopsy It is often recommended to confirm or make the diagnosis and look for cancer. the histopathological signs are of a lichenoid tissue reaction affecting the epidermis.

Typical features include:

• Irregularly thickened epidermis
• Degenerative skin cells
• Liquefaction degeneration of the basal layer of the epidermis
• Inflammatory cell band just below the epidermis
• Melanin (pigment) below the epidermis

Direct immunofluorescent staining can reveal deposits of immunoglobulins at the base of the epidermis.

Patch Tests for patients with oral lichen planus that affects the gums and who have amalgam fillers may be recommended to assess contact allergy to thiomersal (a mercurial compound).

What is the treatment for lichen planus?

Treatment is not always necessary. Local treatments for symptomatic skin or mucosal disease are:

• Powerful current steroids
• Topical calcineurin inhibitors, tacrolimus ointment and pimecrolimus cream
• Current retinoids
• Intralesional steroid injections

Systemic treatment for extended Lichen planus or severe local disease often includes a 1-3 month oral prednisone cycle, while another agent begins from the following list:

• Acitretin
• Hydroxychloroquine
• Methotrexate
• Azathioprine
• Mycophenolate mofetil
• Phototherapy

In cases of oral lichen planus affecting the gums with a contact allergy to mercury, lichen planus can be resolved by replacing the fillers with composite material. If lichen planus is not due to a mercury allergy, removing amalgam fillings is highly unlikely to produce a cure.

Anecdotal success is reported from long courses of oral antibiotics and oral antifungal agents. Lichen planopilaris is reported to improve with pioglitazone.

What is the outlook for lichen planus?

Cutaneous lichen planus tends to disappear within a couple of years in most people, but lichen planus of the mucosa is more likely to persist for a decade or more. Spontaneous recovery is unpredictable and lichen planus may reappear at a later date. Scarring is permanent, including baldness on the scalp.

Lichenoid drug eruptions slowly disappear when the responsible medication is withdrawn.