Although alopecia can come into on...

Although alopecia can come into one's head anywhere on the body, it is chiefly distressing when it affects the scalp. Hair los can range from a small bare patch that is easily masked by means of hairstyling to a more diffuse and obvious pattern. Alopecia in women has been set up to have significantly deleterious imports on self-esteem, psychologic well-being, and corpse image. (1,2)

Pathophysiology

each hair follicle continually goes between the walls of three phases: anagen (growth), catagen (involution, or a brief transition between bourgeoning and resting), and telogen (resting). (3) Disorders of alopecia can be divided into those in which the hair follicle is normal on the other hand the cycling of hair expansion is abnormal (e.g., telogen effluvium) and those in which the hair follicle is damaged (eg cicatricial alopecia).

Diagnosis

A careful history many times suggests the underlying cause of alopecia. Crucial factors include the duration and pattern of hair los whether the hair is weakened or shed at the foundations and whether shedding or thinning has increased. The patient's diet, medications, at hand and past medical conditions, and family history of alopecia are other important factors.

The physical examination has three parts. First, the scalp is examined for evidence of erythema, scaling, or inflammation. Follicular units are apparent in nonscarring alopecias on the contrary absent in scarring types. next to the first the density and distribution of hair are assessed. Third, the hair shaft is examined for caliber, duration shape, and fragility. (4)

The "pull test" is an easy technique for assessing hair los Approximately 60 hairs are grasped between the thumb and the index and middle fingers. The hairs are then gently unless firmly pulled. A negative example (six or fewer hairs obtained) indicates normal shedding, whereas a positive exhibition (more than six hairs obtained) indicates a proces of active hair shedding. Patients should not shampoo their hair 24 hours before the trial is performed.4 If the diagnosis is not clear based upon the history and physical examination, gooded laboratory tests and, occasionally, puncture biopsy may be indicated. A stepwise approach to the diagnosis of hair los is provided in Figure 1 (56)

Androgenetic Alopecia

Androgenetic alopecia, or hair los mediated through the presence of the androgen dihydrotestosterone, is the most numerous common form of alopecia in men and women Almost all bodys have some degree of androgenetic alopecia. (7) The hair los usually begins between the ages of 12 and 40 years and is not seldom insufficient to be noticed. However, visible hair los take places in approximately one half of all [i]role[/i]s by the age of 50 years (8) (Figure 2) In women hairstyling may mask early hair loss

Hair follicles contain androgen receptors. In the neighborhood of androgens, genes that shorten the anagen phase are activated, and hair follicles shrink or become miniaturized. With successive anagen round of yearss the follicles become smaller (leading to shorter, finer hair), and nonpigmented vellus hairs replace pigmented terminal hairs. In women the thinning is diffuse, still more marked in the frontal and parietal regions. on the same level persons with severe androgenetic alopecia almost always have a thin fringe of hair frontally. The remaining hair configuration may bear likeness [i]or[/i] resemblance to a monk's haircut.

Women with androgenetic alopecia do not have higher of the same heights of circulating androgens. However, they have been build to have higher levels of 5a-reductase (which interchanges testosterone to dihydrotestosterone), more androgen receptors, and lower flushs of cytochrome P450 (which re-creates testosterone to estrogen). (6)

chiefly women with androgenetic alopecia have normal mense normal fertility, and normal endocrine function, including gender-appropriate horizontals of circulating androgens. Therefore, an extensive hormonal work-up is unnecessary. If a woman has irregular mense abrupt hair los hirsutism, or acne return an endocrine evaluation is appropriate. In this situation, total testosterone, clear testosterone, dehydroepiandrosterone sulfate, and prolactin of the same heights should be obtained. (6)

Because the hair los in androgenetic alopecia is an aberration of the normal hair period it is theoretically reversible. Advanced androgenetic alopecia, however, may not answer to treatment, because the inflammation that encloses the bulge area of the follicle may irreparably damage the follicular scion cell.

TREATMENT

Minoxidil (Rogaine). The generally preferred treatment for androgenetic alopecia is topically administered 2 percent minoxidil. (689) Minoxidil appears to affect the hair follicle in three ways: it increases the longitudinal dimensions of time follicles spend in anagen, it "wakes up" follicles that are in catagen, and it enlarges the actual follicles. The mechanism from which minoxidil effects these changes is not known. Vellus hairs enlarge and are transformed to terminal hairs. In addition, shedding is reduced

In a randomized, controll double-blind clinical trial involving 550 women 18 to 45 years of age, treatment with 2 percent minoxidil solution comeed in a higher hair compute compared with placebo. (10) [Evidence label A, randomized controll trial] In another investigation (11) 50 percent of women treated with 2 percent minoxidil had at least minimal hair regrowth and 13 percent had moderate regrowth No significantly increased benefit has been shown for the 5 percent minoxidil solution compared with the 2 percent solution. (8)