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DictionarySeeacnekeloid acne
keloid acne[′kē‚lȯid ′ak·nē] (medicine) Acnelike infection of hair follicles, especially on the nape of the neck, resulting in hard, white or reddish keloids and scarring. Also known as folliculitis keloidalis. keloid acne
acne [ak´ne] a disorder of the skin with eruption of papules or pustules; more particularly, acne vulgaris.acne congloba´ta (conglobate acne) severe acne, seen almost exclusively in males, with many comedones, marked by suppuration, cysts, sinuses, and scarring.cystic acne acne with the formation of cysts enclosing a mixture of keratin and sebum in varying proportions.acne ful´minans a rare form of severe cystic acne seen in teenage boys, characterized by highly inflammatory nodules and plaques that undergo suppurative degeneration leaving ulcerations, fever, weight loss, anemia, leukocytosis, elevated erythrocyte sedimentation rate, and polyarthritis.acne indura´ta a progression of papular acne, with deep-seated and destructive lesions that may produce severe scarring.keloid acne keloid folliculitis.acne necro´tica milia´ris a rare and chronic form of folliculitis of the scalp, occurring principally in adults, with formation of tiny superficial pustules that are destroyed by scratching. See also acne varioliformis.acne neonato´rum acne vulgaris in infants, usually in males before 3 months of age, chiefly characterized by papules, pustules, and open and closed comedones on the face; it is thought to be due to hormonal stimulation of sebaceous glands. The affected child may be predisposed to more severe acne in adolescence.acne papulo´sa acne vulgaris with the formation of papules.acne rosa´cea a form of acne in which the skin around each pustule is a rosy red; it is usually seen in persons over 25 years of age and is often psychogenic.tropical acne (acne tropica´lis) a severe type of acne vulgaris seen in the tropics when the weather is hot and humid, characterized by large painful cysts, nodules, and pustules that lead to the formation of rounded abscesses and frequent scarring and tend to localize on the back, nape of the neck, buttocks, thighs, and upper arms and usually sparing the face. It tends to affect those who have had acne vulgaris at an earlier age.acne variolifor´mis a rare condition with reddish-brown, papulopustular umbilicated lesions, usually on the brow and scalp; probably a deep variant of acne necrotica miliaris.acne venena´ta acne produced by contact with any of numerous chemicals, including those used in cosmetic and grooming agents and in industry.acne vulga´ris a chronic skin disorder usually seen in adolescents and young adults, in which there is increased production of sebum (oil) from the sebaceous glands and formation of comedones (blackheads and whiteheads) that plug the pores. Noninflammatory acne produces plugged follicles and a few pimples. Inflammatory acne is characterized by many pimples, pustules, nodules, and inflamed cysts. The lesions are found on the face, neck, chest, back, and shoulders.Treatment. The noninflammatory lesions often respond to over-the-counter creams and lotions, but inflammatory lesions may require intensive and individualized medical treatment under the direction of a dermatologist. Acne is treated by both topical and systemic drugs; the one most frequently recommended is benzoyl peroxide in a 5 or 10 per cent concentration. It is applied to the skin daily or as frequently as necessary to produce mild dryness of the skin. A mainstay for treatment of inflammatory acne continues to be oral tetracycline, which is effective for most cases and safe even when taken for years. A relatively new systemic drug for severe, treatment-resistant acne is isotretinoin (13-cis-retinoic acid). It inhibits the secretion of sebum and alters the lipid composition of the skin surface. Isotretinoin is a teratogen; hence it is not given to pregnant women. It can also cause bone changes. Minor side effects include dry mouth and dry eyes. Another agent used against acne is tretinoin (all-trans-retinoic acid), which is applied topically to reduce the number of comedones and to prevent formation of inflammatory lesions. Acne therapy can continue for months and even years. Patients who conscientiously follow the prescribed regimen greatly increase their chances for improvement and the prevention of permanent scarring and pitting of the skin. When acne has left permanent, disfiguring scars, there are medical techniques that can remove or improve the blemishes. One method is planing with a rotary, high-speed brush. This removes the outer layer of pitted skin, leaving the growing layer and the layers containing the glands and hair follicles. New epithelium grows from the layers underneath; it is rosy at first and gradually becomes normal in color. The technique has also been used successfully in removing some types of disfigurations resulting from accidents. This so-called “sand-paper surgery” or dermabrasion is recommended only for selected cases of acne and results are not always satisfying.Patient Care. Because patients with acne often have a lack of knowledge about the nature of their skin disorder, patient education is a major component of care. Additionally, the disorder often affects young people at a time when they are deeply concerned about their appearance and acceptance by their peers. Adolescents need to know that their concerns are taken seriously. Even though the disorder is not life-threatening, it can adversely affect one's self-image and self-esteem. Laypersons often are misinformed about the cause and effects of acne. It is not a contagious disease, nor is it due to uncleanliness or poor personal hygiene. It is not caused or made worse by lack of sleep, constipation, masturbation, venereal disease, or by anger or hostility. Dietary indiscretion can sometimes contribute to the appearance of lesions, but there are very few people who can find a cause-effect relationship between certain foods they have eaten and the appearance of acne lesions. In general, cola drinks, chocolate, and fried foods need not be restricted or eliminated from the diet in hopes that acne can be avoided or cured. A well-balanced diet is all that is recommended for the management of acne. Scrubbing the skin and using harsh soaps is not recommended because this only serves to damage the skin and predispose it to breakdown. A mild soap is as effective as special medicated soaps. If the hair is excessively oily, it may help to shampoo regularly and keep the hair off the face. Pimples and pustules should not be squeezed. This can press the sebum and accumulated debris more firmly into the clogged duct and increase the chance of inflammation and the spread of infection. Blackheads and whiteheads are best removed by applying a prescription medication that causes peeling of the skin. Since the management of acne can go on for years, requiring periodic evaluation by a dermatologist, patients and their families will need continued support and encouragement. Patients taking prescription medications will need to know the expected results, any adverse reactions that might occur, their symptoms, and to whom they should be reported.ke·loid ac·ne (kē'loyd ak'nē) A form of dermatologic disease most common in African Americans involving inflammation and pyogenesis about follicular structures, particularly on the back of the neck. acne (ak'ne) [Ult. fr. acme] An inflammatory disease of the sebaceous follicles of the skin, marked by comedones, papules, and pustules. It is exceptionally common in puberty and adolescence. Acne usually affects the face, chest, back, and shoulders. In severe cases, cysts, nodules, and scarring occur. Synonym: common acne; acne vulgarisEtiologyThe cause is unknown, but predisposing factors include hereditary tendencies and disturbances in the androgen-estrogen balance. Acne begins at puberty when the increased secretion of androgen in both males and females increases the size and activity of the pilosebaceous glands. Specific inciting factors may include food allergies, endocrine disorders, therapy with adrenal corticosteroid hormones, and psychogenic factors. Vitamin deficiencies, ingestion of halogens, and contact with chemicals such as tar and chlorinated hydrocarbons may be specific causative factors. The fact that bacteria are important once the disease is present is indicated by the successful results following antibiotic therapy. The lesions may become worse in women and girls before the menstrual period. SymptomsAcne vulgaris is marked by either papules, comedones with black centers (pustules), or hypertrophied nodules caused by overgrowth of connective tissue. In the indurative type, the lesions are deep-seated and cause scarring. The face, neck, and shoulders are common sites. Acne may be obstinate and recurrent. TreatmentTreatments include skin cleansing, topical agents (e.g., azelaic acid or benzoyl peroxide or vitamin A derivatives), and oral or topical antibacterial drugs. Patient careThe patient is instructed to wash the skin thoroughly but gently, avoiding intense scrubbing and skin abrasion; to keep hands away from the face and other sites of lesions; to limit the use of cosmetics; and to observe for, recognize, and avoid or modify predisposing factors that may cause exacerbations. The need to reduce sun exposure is explained, and the patient is advised to use a sunscreen agent when vitamin A acid or tetracycline is prescribed. Information is provided to fill knowledge gaps or correct misconceptions, and emotional support and understanding are offered, particularly if the patient is an adolescent. Patients (and others) need to be aware that extensive use of antibiotic treatment for acne increases the prevalence of antibiotic-resistant facial bacteria and can affect treatment response. Most improvement occurs during the first 6 weeks of therapy, whatever the regimen. More than half of all patients respond to therapy. Colonization with tetracycline-resistant propionibacteria diminishes response to all oral antibiotic regimens. Skin irritation as an adverse effect to treatment occurs most commonly with topical benzoyl peroxide alone, which is the most cost-effective treatment. Adding topical erythromycin may help reduce irritation and increase efficacy. CAUTION!Because of the teratogenicity of some acne medications (such as isotretinoin), pregnancy must be avoided during their use. acne atrophicaAcne with residual pitting and scarring. bromide acneThe characteristic acne caused by bromide. acne ciliarisAcne that affects the edges of the eyelids. common acneAcne.acne conglobataAcne vulgaris with abscesses, cysts, and sinuses that leave scars.CYSTIC ACNEcystic acneAcne with cysts containing keratin and sebum. See: illustrationTreatmentIsotretinoin, a vitamin A derivative, has been effective in treating this condition. For Caution concerning its use, See: isotretinoin illustrationacne fulminansA rare type of acne in teenage boys, marked by inflamed, tender, ulcerative, and crusting lesions of the upper trunk and face. It has a sudden onset and is accompanied by fever, leukocytosis, and an elevated sedimentation rate. About half of the cases have inflammation of several joints. halogen acneAcne due to exposure to halogens such as bromine, chlorine, or iodine.acne indurataAcne vulgaris with chronic, discolored, indurated surfaces.keloid acneAcne keloidalis nuchae .acne keloidalis nuchae Chronic follicular infection of the skin at the occiput (base of the skull) and the neck. It occurs most often in men of African heritage and causes scars and thickening of the skin. Synonym: keloid acneacne keratosaAcne in which suppurating nodules crust over to form horny plugs. These occur at the corners of the mouth. acne neonatorumAcne occurring in newborns. It is common, appearing about the second to fourth week of life. Comedones, inflamed papules, and pustules may be seen (the latter yield staphylococcal species when cultured). The rash typically resolves spontaneously by the third or fourth month of life. Lesions are typically seen on the chin, cheeks, and forehead. Usually no treatment is required, but keratolytic agents may be used for severe cases. ACNE PAPULOSAacne papulosaAcne characterized by formation of papules with very little inflammation. See: illustrationillustrationpetroleum acneAcne that may occur in those who work with petroleum and oils.acne pustulosaAcne with pustule formation and subsequent deep scars.acne rosaceaRosacea.steroid acneAcne caused by systemic or topical use of corticosteroid drugs.summer acneAcne that appears only in hot, humid weather or that is much worse in such weather. Although the exact cause is unknown, the condition is not caused by increased exposure to the sun's rays. tropical acneSevere acne caused by or aggravated by living in a hot, humid climate. The skin of the thorax, back, and legs is most commonly affected. acne urticariaAn acneiform eruption of itching wheals. acne varioliformisVesiculopustular folliculitis that occurs mostly on the temples and frontal margins of the scalp but may be seen on the chest, back, or nose.acne vulgarisAcne.keloid acne A persistent (chronic) inflammation of the hair follicles, especially on the back of the neck, that produces hard reddish or white KELOID-like scars.FinancialSeeAcne |