Hair and Nail Diseases

Androgenic alopecia is premature loss of hair of the central scalp.

Alopecia is a physiologic reaction induced by androgens in genetically predisposed men.

The pattern of inheritance is probably polygenic.

It can begin any time after puberty and usually is fully expressed by the time the patient is in his 40s.

Terminal hair follicles are transformed into vellus-like follicles.

Terminal hair is replaced by fine light vellus hair, which is shorter and has a reduced diameter.

With time, further atrophy occurs, leaving the scalp shiny and smooth. The follicles disappear.

It begins with bitemporal thinning that then progresses to an M-shaped recession. Then there is a loss of hair focally in the crown of the scalp, which extends to total hair loss in the central scalp.

There is increased growth of secondary sexual hair (on the chest, in the axillae, and in pubic and beard areas).

The progression and various patterns of hair loss have been classified by Hamilton. Triangular frontotemporal recession occurs normally in most young men (type I) and women after puberty. The first signs of balding are increased frontotemporal recession accompanied by midfrontal recession (type II). Hair loss in a round area on the vertex follows, and the density of hair decreases, sometimes rapidly, over the top of the scalp (types III–VII).

Minoxidil (Rogaine) is a topical 2% or 5% (extra strength for men) solution or 5% foam for use in men that is available over the counter.

It is applied to a dry scalp twice a day. The 5% solution results in greater hair growth.

Ideal candidates are men younger than 30 years.

Regrowth takes 8 to 12 months, peaks at 1 year, but can be maintained 5 years later with continued use.

It may help stop further loss but must be used continually to preserve growth.

Finasteride (Propecia) at optimal dose of 1 mg/day is an oral prescription medication taken daily. Caution is needed in patients with liver abnormalities.

The drug works by blocking type II 5α-reductase in hair follicles, lowering serum and scalp levels of dihydrotestostersone, while maintaining testosterone levels.

Hair growth peaks at 1 to 2 years. Anterior and midscalp and vertex hair loss is improved compared with placebo.

It must be used daily and chronically to maintain regrowth. One study reported a 21.6% increase in hair weight and a 7.2% increase in hair count from baseline at 192 weeks.

Decreased libido, ejaculation disorders, orgasm disorders, and erectile dysfunction can continue after discontinuation of the drug, which has a U.S. Food and Drug Administration (FDA) revised label warning.

Label warnings also include reports of male infertility and of decreased semen quality.

It is Pregnancy Category X and is contraindicated for women of childbearing potential. Feminization of the male fetus is a risk in pregnant patients who take finasteride.

Dutasteride is another 5α-reductase inhibitor; it is not approved by the FDA for hair loss, and phase III trials for hair loss indication are on hold.

Hair transplantation has have been used successfully for years to permanently restore hair.

Hair weaves have been refined in a process whereby strands of human hair are applied to a thin nylon filament anchored to the scalp with the patient's own hair.

An anteroposterior elliptic excision of bald vertex scalp with primary closure can provide an instant hair effect.

Both finasteride and minoxidil need to be used lifelong for continued efficacy.

Both finasteride and minoxidil are more likely to be effective if use begins at the earliest onset of hair loss.

Presently there is limited efficacy of current medical treatments for hair loss. Although the risks of such treatments are minimal, the continued costs and possible sexual dysfunction indicated by expanded FDA labeling may outweigh the benefits.

Androgenetic alopecia in women is a common hereditary, central, diffuse hair thinning that begins at a relatively early age. This is in contrast to postmenopausal hair loss, which begins in women in their 50s, 60s, or 70s. Affected scalp hairs have a shortened anagen cycle and progressive miniaturization of hair follicles.

Inheritance of androgenetic alopecia is poorly understood, although clearly there is genetic predisposition to pattern hair loss. Female pattern hair loss can be early or late onset with or without high androgen levels.

The true prevalence is unknown, but it may affect 6% to 25% of premenopausal women.

Women rarely become completely bald like men.

Hereditary hair thinning begins in the woman's teenage years, 20s, or 30s, and is usually fully expressed by the 40s. There are two peaks of onset: in the 20s and the 40s.

Hair loss is gradual, not abrupt or massive.

Menses is normal and regular. Heavy menses causes iron deficiency and increased hair shedding. Pregnancies are normal, and there is no infertility or galactorrhea.

Certain drugs cause hair thinning. Hair regrows when the drug is stopped.

Recent discontinuation of an estrogenic oral contraceptive may lead to hair loss.

Contraceptives containing androgenic progestins (nortestosterone derivatives, e.g., levonorgestrel) may cause or prolong androgenetic alopecia. This is a side effect of levonorgestrel-releasing implants.

The gonadotropin-releasing hormone antagonists triptorelin and goserelin, the oral esterified estrogen methyltestosterone used for menopause symptoms, and the nonsteroidal aromatase inhibitors letrozole and vorozole used for hormone-sensitive breast cancer may lead to androgenetic alopecia.

Most women experience a gradual loss of hair on the central top of the scalp, with retention of the normal hairline without frontotemporal recession, and the scalp becomes more visible.

Alopecia in frontovertical and temporoparietal supra-auricular areas may occur in some, resulting in a “Christmas tree” form of alopecia anteriorly.

There is increased spacing between hairs, often pencil eraser−sized areas lacking visible hairs.

There are a variety of hair diameters in the central scalp. Many of the hairs are miniaturized (thin and short). Hairs along the frontal hairline are normal.

Hair diameters become thinner over time. This is noticed when the hair is gathered into a ponytail.

Baseline laboratory tests to rule out medical causes of hair loss include evaluation for thyroid disease, iron deficiency, and connective tissue disease. It is reasonable to check the antinuclear antibody level for connective tissue disease.

The level of thyroid-stimulating hormone should be determined to rule out a treatable thyroid disease.

Patients with heavy menses should have the following tests: serum iron determination, total iron-binding capacity, and ferritin level. Replacement of low iron state may be helpful.

Most patients do not require hormonal evaluation. Most women have no signs of hyperandrogenemia and have normal serum androgen levels; however, 5-alpha DHT, dehydroepiandrosterone sulfate (DHEAS), serum free testosterone, 17-beta-hydroxyprogesterone, delta-4-androstenedione, sex hormone−binding globulin, and cortisol and prolactin levels should be determined if one or more of the following is present: irregular menses, hirsutism, virilization, acne, galactorrhea, or infertility. A subset of women may have polycystic ovarian disease (PCOS) and insulin resistance. A ratio of luteining hormone to follicle-stimulating hormone (LH:FSH ratio) greater than or equal to 3 is typical of PCOS.

Scalp biopsy is performed in patients suspected of having a scarring alopecia. Biopsy is sometimes performed to rule out the diffuse form of alopecia areata or telogen effluvium.

The term “female pattern baldness” should be avoided. Instead, the term “female pattern hair loss” should be used when talking to patients.

Topical minoxidil 2% solution (Rogaine) is the standard treatment and may be effective in some women. It is applied twice a day for a trial of 6 months. If effective, it must be continued for persistent effect. If there is no response, the 5% solution may be tried twice daily. The 5% solution is approved for use in men. It may result in unwanted facial hair.

Patients with abnormal laboratory studies can be referred to an endocrinologist or a gynecologist.

There are no restrictions on frequency of washing, combing, hair coloring, or permanents.

Estrogen is not prescribed to treat women for androgenetic alopecia.

Spironolactone is sometimes used in divided doses of 50 to 200 mg/day; it is Pregnancy Category D and may elevate serum potassium.

Although finasteride is helpful in men, in women a dose of 1 mg daily was not beneficial in a 1-year study of 137 postmenopausal women. It may be more helpful in women with hyperandrogenism.

Women with androgenetic alopecia who desire an oral contraceptive should use a progestin with little androgenic activity—such as norgestimate or desogestrel. One study reports an increased hair growth in postmenopausal women taking finasteride 2.5 mg/day in combination with an oral contraceptive pill containing drospirenone and ethinyl estradiol.

Hair loss is a common complaint in women and can be emotionally devastating.

Widening of the “Christmas tree” pattern of loss is evident with hair loss of the frontal scalp exceeding loss of the occiput. This part is often the earliest visible change. Diffuse thinning and hair shedding occur, most commonly after menopause.

Telogen effluvium is a nonscarring, noninflammatory, diffuse hair loss (alopecia) that is typically sudden in onset and occurs 3 to 5 months after a systemic stress, such as childbirth, a severe medical illness, crash dieting, severe stressors, surgery, and high fever and occasionally in response to medication.

Telogen effluvium may be acute or chronic. The acute form occurs abruptly after a specific trigger and is of less than 12 months' duration.

Chronic telogen effluvium may or may not have an identifiable inciting stressor; it may be acute or slow in onset and greater than 12 months' duration.

The hair loss is often most noted by the patient as clumps of hair coming out in the shower or in the hairbrush.

The quantity of hair lost each day is often dramatic, very noticeable, and distressing to the patient; however, such loss may not be easily detected on direct inspection by others.

The hair loss typically occurs 3 months after the inciting stressor because the loss is a result of anagen (growing-phase) hairs shifting abruptly into catagen (the apoptotic stage), and then into telogen (resting-phase) when the hair is lost.

Not all anagen hairs undergo this stage shift; the quantity of hairs shifting stage determines the amount of loss.

The most common form of telogen effluvium results from early conversion of hairs to telogen phase, as noted associated with systemic stress, such as surgery, major illness, and crash dieting. The hair loss occurs 3 to 5 months after the major stress.

Telogen effluvium can also be caused by a delayed anagen release, whereby affected hairs are delayed in their conversion to telogen hairs; this type of telogen effluvium occurs after childbirth. When delayed anagen release occurs, hairs cycle into telogen and are shed 3 to 5 months later.

Drug-induced telogen effluvium is the most common drug-induced hair loss. Most drugs do this by causing the follicle to prematurely arrest and cease growth. There are many drugs associated with hair loss. Severe hair shedding (>200–300 hairs a day) is uncommon but can be seen in patients taking interferons, heparin, and antineoplastic agents. Onset is typically within days to weeks of new medication introduction or dosage increase.

Chronic telogen effluvium is believed to be caused by a short anagen cycle. Affected patients are typically middle-aged women with thick hair before onset of shedding.

Hair loss in infants occurs between birth and 4 months; regrowth is typical by 6 months.

The scalp hairs are primarily affected; the density of hairs is variably reduced. Early on, the reduction in hair density may be undetectable by the clinician.

The hair density as manifest by the part width is similar at the occiput and at the crown.

Pull test is positive: gentle pulling of hair clumps in multiple regions of the scalp will yield more than two or three telogen (club) hairs per pull.

Bitemporal thinning may be observed.

The fingernails may show horizontal ridges (Beau's lines) that indicate a similar growth arrest occurring several months previously.

Hair pluck is an uncomfortable test in which at least 10 hairs are plucked from the scalp. Examination of the hair bulbs using light microscopy will yield an increased telogen-to-anagen ratio above the normal ratio of 1 : 10. This test is rarely required for diagnosis and is uncomfortable for the patient.

Biopsy is not typically indicated if the clinical findings and history are supportive. Biopsy shows an increased number of telogen and catagen follicles, but no inflammation or miniaturization of hair follicles. A 4-mm punch biopsy for horizontal sectioning should show between 25 and 50 hairs; more than 12% to 15% of the hairs would be in telogen.

Consider the ratio of iron to total iron-binding capacity. Ferritin may be low in patients with anemia, vegetarians, or those with a history of heavy menstrual cycles.

Anorexia, crash dieting, or dramatic weight loss may manifest as low ferritin, albumin, and total protein.

Thyroid function tests are indicated if symptoms or signs of thyroid disease are present.

This form of hair loss does not affect all hairs; thus, the loss of hairs is never total.

Regrowth of hairs occurs in 95% by 12 months; there is no scarring or permanent loss.

Sometimes regrowth occurs during a time when the affected patient is also experiencing hair loss due to miniaturization of hairs as occurs in androgenetic alopecia; in this case, regrowth of hair may not appear as complete.

The course of chronic telogen effluvium is unpredictable. It is often waxing and waning and may last several months to several years.

Androgenetic alopecia

Diffuse form of alopecia areata (biopsy may be necessary)

Loose anagen hair syndrome (the pull test should yield some anagen hairs)

Spontaneous regrowth is the rule.

No treatment is likely to shorten the course or hasten regrowth.

If medications are responsible, they should be discontinued if possible. The list of medications is long and includes anticoagulants, beta-blockers and angiotensin-converting enzyme inhibitors, hormones, anticonvulsants, lithium, and others.

The most important aspect of treatment is an emotionally supportive relationship during the evaluation, diagnosis, and follow-up.

Education of the patient regarding hair cycle dynamics, the short arrest in growth due to a specific stressor, and the likelihood of regrowth are helpful and reassuring details to discuss.

Minoxidil 5% solution applied twice daily may be helpful for chronic telogen effluvium.