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Absence or loss of hair. SYN: baldness, calvities, pelade. [G. alopekia, a disease like fox mange, fr. alopex, a fox]
- a. adnata underdevelopment of the lashes. SEE ALSO: a. congenitalis, milphosis. SYN: madarosis (2).
- androgenic a. gradual decrease of scalp hair density in adults with transformation of terminal to vellus hairs, which become lost as a result of familial increased susceptibility of hair follicles to androgen secretion following puberty. Two areas of the scalp are commonly affected in men; when it occurs in females it is associated with other evidence of excessive androgen activity, such as hirsutism. Autosomal dominant inheritance. See female pattern a., male pattern a.. SYN: common baldness.
- a. areata [MIM*104000] a common condition of undetermined etiology characterized by circumscribed, nonscarring, usually asymmetrical areas of baldness on the scalp, eyebrows, and bearded portion of the face. Hairy skin anywhere on the body may be affected; occasionally follows autosomal dominant inheritance. Peribulbar lymphocytic infiltration and association with autoimmune disorders suggest an autoimmune etiology. Slow enlargement with eventual regrowth within 1 year is common, but relapse is frequent and progression to a. totalis may occur, especially with childhood onset.
- a. capitis totalis SYN: a. totalis.
- a. congenitalis absence of all hair at birth. May be associated with psychomotor epilepsy [MIM*104130]; autosomal dominant or X-linked [MIM*300042] inheritance. SYN: congenital baldness, hypotrichiasis (2).
- female pattern a. diffuse partial hair loss in the centroparietal area of the scalp, with preservation of the frontal and temporal hairlines; the most frequent type of androgenic a. in women.
- a. leprotica thinning or total loss of the lateral third of the eyebrows, eyelashes, and body hairs, seen in leprosy; loss of scalp hair is rare.
- lipedematous a. a. with itching, soreness, or tenderness of the scalp in black women; the scalp is thickened and soft, subcutaneous fat is increased, and the hair is sparse and short.
- male pattern a. [MIM*109200] the most common form of androgenic a., seen in men as receding frontal and bilateral triangular temple hairlines, and a balding patch on the vertex, which may progress to complete a.; inheritance is autosomal dominant in males, recessive in females. SYN: a. hereditaria, male pattern baldness, patterned a..
- a. marginalis hair loss at the hairline, a condition most commonly seen in blacks; commonly transient and caused by chronic traction, although long-continued traction may cause permanent a.. SYN: a. liminaris frontalis.
- a. medicamentosa diffuse hair loss, most notably of the scalp, caused by administration of various types of drugs.
- moth-eaten a. patchy hair loss of parietal and occipital regions of the scalp, characteristic of secondary syphilis.
- a. mucinosa follicular mucinosis with a. appearing in areas of erythema and edema in the bearded portion of the face or in the scalp.
- a. presenilis ordinary or common baldness occurring in early or middle life without any apparent disease of the scalp.
- pressure a. loss of hair over a circumscribed area usually on the posterior scalp, resulting from the continuous pressure on the occiput in a lengthy operative procedure, or unconsciousness following a drug overdose. SYN: postoperative pressure a..
- scarring a. a. in which hair follicles are irreversibly destroyed by scarring processes including trauma, burns, lupus erythematosus, lichen planopilaris, scleroderma, folliculitis decalvans, or of uncertain cause (pseudopelade). SYN: cicatricial a..
- a. symptomatica a. occurring in the course of various constitutional or local diseases, or following prolonged febrile illness.
- a. syphilitica moth-eaten a. of secondary syphilis.
- a. totalis total loss of hair of the scalp either within a very short period of time or from progression of localized a., especially a. areata. Cf.:a. universalis. SYN: a. capitis totalis.
- traction a. circumscribed or diffuse loss of hair resulting from repetitive traction on the hair by pulling or twisting; also occurs after excessive application of hair “softeners” such as permanent wave solutions or hot combs. A. marginalis is a form of traction a.. SYN: traumatic a..
- a. triangularis congenitalis a congenital triangular patch of baldness on the frontal or temporal region of the scalp.
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al·o·pe·cic -'pē-sik adj
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(baldness)
n.
absence of hair from areas where it normally grows. Non-scarring alopecias include common baldness in men, which is familial, and andro-genetic alopecia in women, in which the hair loss is associated with increasing age. Acute hair fall (telogen effluvium), in which much or all of the hair is shed but starts to regrow at once, may occur after pregnancy or a serious illness. Alopecia areata consists of bald patches that may regrow; it is an example of an organ-specific autoimmune disease. In scarring (or cicatricial) alopecias the hair does not re-grow; examples include lichen planus and discoid lupus erythematosus. Alopecia totalis is loss of all the hair, due to an autoimmune condition; in some 70% of cases it regrows within a few years.
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al·o·pe·cia (al″o-peґshə) [Gr. alōpekia a disease in which the hair falls out] lack or loss of hair from skin areas where it normally is present. Called also atrichia, baldness, and calvities.Medical dictionary. 2011.