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lichen planus Note: This page may contain terms or definitions that are offensive or inappropriate for some readers.ThesaurusNoun | 1. | lichen planus - an eruption of shiny flat-topped purplish (usually itchy) papules on the wrist and forearms and thighslichen ruber planuslichen - any of several eruptive skin diseases characterized by hard thick lesions grouped together and resembling lichens growing on rocks | TranslationsLichen Planus Note: This page may contain terms or definitions that are offensive or inappropriate for some readers.lichen planus[‚līk·ən ′plan·əs] (medicine) A dermatologic disease of unknown etiology that also occurs in the mouth, on the tongue, or on the lips as smooth lacy networks of white lines or, less commonly, as white patches that may become ulcerative. Lichen Planus a skin disease characterized by the eruption of pointed flat nodules with a spirally twisted fluffy hair in the center; it is one of the keratoses. It appears in children aged 2 to 3, reaches a peak between ages 15 and 20, and subsides in adulthood; it occurs more often in girls and young women. The eruptions appear mostly on the extensor surfaces of the upper and lower limbs, the buttocks, and, sometimes, the scalp. Lichen planus is associated with dry skin and slight scaling of the skin, especially on the external surface of the upper and lower limbs. The disease is often a congenital anomaly; it may be a manifestation of hypovitaminosis A. Treatment is protracted and calls for large doses of vitamins A and E and warm baths followed by rubbing in ointments containing vitamin A and agents that dissolve the horny layer of the skin. Sea bathing combined with sunbaths and radon and hydrogen sulfide baths are beneficial. REFERENCESPopkhristov, P. Kozhnye bolezni v detskom vozraste. Sofia, 1963. (Translated from Bulgarian.) Spravochnik po kosmetike. Edited by M. A. Rozentul. Moscow, 1964. Mashkilleison, L. N. Lechenie i profilaktika kozhnykh boleznei. Moscow, 1964.IU. K. SKRIPKIN and G. IA. SHARAPOVA lichen planus Note: This page may contain terms or definitions that are offensive or inappropriate for some readers.Lichen Planus DefinitionLichen planus is a skin condition of unknown origin that produces small, shiny, flat-topped, itchy pink or purple raised spots on the wrists, forearms or lower legs, especially in middle-aged patients.DescriptionLichen planus affects between 1-2% of the population, most of whom are middle-aged women. The condition is less common in the very young and the very old. The lesions are found on the skin, genitals, and in the mouth. Most cases resolve spontaneously within two years. Lichen planus is found throughout the world and is equally distributed among races.Causes and symptomsNo one knows what causes lichen planus, although some experts suspect that it is an abnormal immune reaction following a viral infection, probably aggravated by stress. The condition is similar to symptoms caused by exposure to arsenic, bismuth, gold, or developers used in color photography. Occasionally, lichen planus in the mouth appears to be an allergic reaction to medications, filling material, dental hygiene products, chewing gum or candy.Symptoms can appear suddenly, or they may gradually develop, usually on the arms or legs. The lesions on the skin may be preceded by a dryness and metallic taste or burning in the mouth.Once the lesions appear, they change over time into flat, glistening, purple lesions marked with white lines or spots. Mild to severe itching is common. White, lacy lesions are usually painless, but eroded lesions often burn and can be painful. As the lesions clear up, they usually leave a brown discoloration behind, especially in dark skinned people.Lichen planus in the mouth occurs in six different forms with a variety of symptoms, appearing as lacy-white streaks, white plaques, or eroded ulcers. Often the gums are affected, so that the surface of the gum peels off, leaving the gums red and raw.DiagnosisA doctor can probably diagnose the condition simply from looking at the characteristic lesions, but a skin biopsy may be needed to confirm the diagnosis.TreatmentTreatment is aimed at easing symptoms. Itching can be treated with steroid creams and oral antihistamines. Severe lesions can be treated with corticosteroids by mouth, or combinations of photochemotherapy (PUVA) and griseofulvin.Patients with lesions in the mouth may find that regular professional cleaning of the teeth and conscientious dental care improve the condition. Using milder toothpastes instead of tartar control products also seems to lessen the number of ulcers and makes them less sensitive.PrognosisWhile lichen planus can be annoying, it is usually fairly benign and clears up on its own. It may take months to reach its peak, but it usually clears up within 18 months.Key termsPUVA — A type of phototherapy that combines the oral or topical photosensitizing chemical psoralen, plus long-wave ultraviolet light-A (UVA).ResourcesOtherLichen Planus Self-Help. Baylor College of Dentistry. http://www.tambcd.edu/lichen.lichen [li´ken] 1. any of certain plants formed by the mutualistic combination of an alga and a fungus.2. any of various papular skin diseases in which the lesions are typically small, firm papules set very close together.lichen amyloido´sus a condition characterized by localized cutaneous amyloidosis.lichen fibromucinoido´sus (lichen myxedemato´sus) a condition resembling myxedema but unassociated with hypothyroidism, marked by mucinosis and a widespread eruption of asymptomatic, soft, pale red or yellowish, discrete papules.lichen ni´tidus a usually asymptomatic chronic inflammatory eruption consisting of numerous glistening, flat-topped, discrete, smooth, commonly skin-colored micropapules, located most often on the penis, lower abdomen, inner thighs, flexor aspects of the wrists and forearms, breasts, and buttocks. Widespread involvement may produce confluence of the lesions, with formation of scaly plaques.lichen pila´ris lichen spinulosus.lichen planopila´ris a variant of lichen planus characterized by formation of cone-shaped horny papules around the hair follicles, in addition to the typical lesions of ordinary lichen planus.lichen pla´nus an inflammatory skin disease with wide, flat, purplish, shiny papules in circumscribed patches; it may involve the hair follicles, nails, and buccal mucosa; called also lichen ruber planus.lichen ru´ber monilifor´mis a generalized or localized eruption with either round, dome-shaped, waxy, dark or bright red papules, or waxy, yellow, milia-like papules, often forming a moniliform (string-of-beads) pattern, sometimes arranged in keloidal bands. Some authorities consider the condition to be a variant of lichen simplex chronicus.lichen ru´ber pla´nus lichen planus.lichen sclero´sus (lichen sclero´sus et atro´phicus) a chronic atrophic skin disease marked by white papules with an erythematous halo and keratotic plugging. It sometimes affects the vulva (kraurosis vulvae) or penis (balanitis xerotica obliterans).lichen scrofuloso´rum (lichen scrofulo´sus) a form of tuberculid manifested as an eruption of clusters of lichenoid papules on the trunk of children with tuberculous disease.lichen sim´plex chro´nicus dermatosis of psychogenic origin, marked by a pruritic discrete, or more often, confluent lichenoid papular eruption, usually confined to a localized area. Mechanical trauma, such as scratching or rubbing the area, is a factor in its development. The lesions may arise from normal skin or they may occur as a complication of other forms of dermatitis. Called also circumscribed or localized neurodermatitis and lichen chronicum simplex. Treatment consists of administration of corticosteroids applied locally as a cream or given by intralesional injection to relieve the pruritus. The area should be protected by light dressings and the patient encouraged to avoid mental stress, emotional upsets, and irritation of the affected area. The application of very hot or very cold compresses may afford temporary relief of the itching. The condition tends to become chronic with unexplained remissions and reappearance of lesions in a different part of the body.lichen spinulo´sus a condition in which there is a horn or spine in the center of each hair follicle; called also lichen pilaris.lichen stria´tus a self-limited condition characterized by a linear lichenoid eruption, usually in children.lichen urtica´tus papular urticaria.li·chen pla·'nuseruption of flat-topped, shiny, violaceous papules on flexor surfaces, male genitalia, and buccal mucosa of unknown cause; may form linear groups; microscopically characterized by a bandlike subepidermal lymphocytic infiltrate. Spontaneous resolution is common after months to years.lichen planus A pruritic dermopathy of flexor surfaces (especially wrist), orogenital mucosa, hands, feet, lower back, and the pretibial area, which is characterised by papular thickening of upper dermis, and a shiny violaceous surface. DiffDx Lichenoid drug reaction, lichenoid keratosis, granuloma annulare, systemic lupus eythematosus, psoriasis. Management Corticosteroids.lichen planus Dermatology A pruritic dermatopathy of flexor surfaces–especially wrist, orogenital mucosa, characterized by papular thickening of upper dermis, a shiny violaceous surface Management Corticosteroidsli·chen pla·nus , lichen ruber planus (lī'ken plā'nŭs, rū'bĕr) Eruption of flat-topped, shiny, violaceous papules on flexor surfaces, male genitalia, and buccal mucosa of unknown cause; may form linear groups. Spontaneous resolution is common after months to years.LICHEN PLANUSLICHEN PLANUSlichen planusAn inflammatory rash marked by the presence of itchy, red to violet, polygon-shaped papules, which typically appear on the scalp, in the oral cavity, or on the limbs. The papules may merge into plaques crisscrossed by Wickham striae. Typically, the rash persists for 1 to 2 years and then spontaneously improves although about one in five patients will suffer a recurrence. Synonym: lichen ruber planus See: illustrationEtiologyThe cause of the rash is unknown, but it is occasionally associated with the use of chemicals (such as photoprocessing compounds, gold) or medications (such as beta blockers, diuretics, nonsteroidal anti-inflammatory drugs). TreatmentCorticosteroids, applied topically, taken orally, or injected into the lesions, are often effective. illustrationSee also: lichenlichen planus An uncommon skin disease featuring small, intensely itchy, slightly raised, reddish-purple patches that enlarge and run together to form flat-topped plaques up to 2 cm in diameter. They are usually found on the fronts of the wrists and forearms, the sides of the calves and ankles and the lower back. The cause is unknown. Lichen planus usually clears up within 2 years. Itching can be relieved by hydrocortisone ointment.Wilson, Sir William J.E., English dermatologist, 1809-1884. Wilson lichen - eruption of flat-topped, shiny, violaceous papules on flexor surfaces, male genitalia, and buccal mucosa of unknown cause. Synonym(s): lichen planusli·chen pla·nus , lichen ruber planus (lī'ken plā'nŭs, rū'bĕr) Eruption of flat-topped violaceous papules on flexor surfaces and buccal mucosa of unknown cause. AcronymsSeeLPlichen planus
Note: This page may contain terms or definitions that are offensive or inappropriate for some readers.- noun
Synonyms for lichen planusnoun an eruption of shiny flat-topped purplish (usually itchy) papules on the wrist and forearms and thighsSynonymsRelated Words |