Alopecia

Definition

Alopecia is the partial or complete loss of hair—especially on the scalp—either in patches (alopecia areata), on the entire head (alopecia totalis), or over the entire body (alopecia universalis).

Description

A basic understanding of hair biology and normal hair development is essential in distinguishing normal versus abnormal hair loss in children and adolescents.

Hair consists of the shaft and the root, which is anchored into a follicle beneath the epidermis. Hair is formed by rapid divisions of cells at the base of the follicle. Except for a few growing cells at the base of the root, hair, which is composed of keratin and other proteins, is dead tissue.

An individual hair follicle has a long growth phase, producing steadily growing hair for two to six years. About 80 percent to 90 percent of hair follicles are involved in this active growing period called the anagen phase. Next is a brief transitional phase (of about three weeks' duration)—the catagen phase—during which the hair follicle degenerates. About 5 percent of follicles are involved in the catagen phase.

Then a dormant period known as the telogen phase occurs. About 10 percent to 15 percent of hairs are involved in this phase, which lasts for approximately three months. Following the telogen phase, the growth phase begins again, and the growth cycle repeats.

Each person has about 100,000 hairs on their scalp. Although it is normal to lose between 25 and 100 hairs per day, any disruption of the hair growth cycle may cause abnormal hair loss.

Demographics

It is estimated that alopecia affects several million children in the United States and that hair loss is responsible for about 3 percent of all pediatric office visits.

Alopecia areata affects both sexes and all ages but is most common in children five to 12 years old. About one per 1000 children has alopecia areata. Approximately 5 percent of children with alopecia areata go on to develop alopecia totalis, and some of these children may develop alopecia universalis.

Tinea capitis (ringworm ) affects an estimated 10 percent to 20 percent of susceptible children, and although the demographics are sketchy, telogen effluvium is the most common type of alopecia in both children and adults.

Causes and symptoms

Although in children and adolescents, hair loss may be caused by a wide variety of factors, most children experience hair loss as a result of one of four major causes:

• fungal infections
• alopecia areata
• trauma to the hair shaft
• telogen effluvium

A fungal infection called tinea capitis, which is similar to athlete's foot, is a common cause of hair loss, particularly among toddlers and early school-aged children. Tinea capitis, which affects the hair root, is a highly contagious condition and is often transmitted when a child uses the comb, brush, hat, or bed linen of an infected child. Tinea capitis seldom occurs after puberty .

Children with this condition usually have patchy hair loss with some broken hairs visible just above the surface of the scalp. The patches of hair loss are usually round or oval but are sometimes irregular in shape. When broken off at the surface, the hairs resemble small black dots on the scalp. Occasionally gray flakes or scales are present.

Alopecia areata, or localized baldness, is the sudden appearance of sharply defined circular or oval patches of hair loss, most often on the scalp. These patches are smooth and without inflammation, scaling, or broken hairs and may appear overnight or over the course of a few days. This condition may affect scalp hair, the eyebrows, eyelashes, genital area, and occasionally the underarms. The hair loss is not accompanied by other visible evidence of scalp disease, and the condition is not contagious.

In alopecia areata, immune system cells (white blood cells) attack the rapidly growing cells in the hair follicles that produce hair. The affected hair follicles decrease in size and hair production slows drastically. Because the stem cells that continually supply the follicles with new cells do not appear to be affected, the follicle retains the potential to regrow hair.

Although it is uncertain why the hair follicles undergo these changes, it is thought that a combination of genes may predispose some children and adults to the disease. In those who are genetically predisposed, some type of trigger—perhaps a virus or something in the child's environment—brings on the attack against the hair follicles.

Trauma to the hair shaft is another common cause of hair loss in children. Often the trauma is caused by traction resulting from, for example, tight braids, ponytails, or by friction (hats, hair bands, or rubbing against a bed). Trauma may also be caused by chemicals or burns .

Another important cause of hair trauma is called trichotillomania—a habit similar to thumb-sucking or nail-biting—of twirling or pulling out the hair. Trichotillomania is generally considered to be a nervous habit and may include the pulling of eyebrows and eyelashes.

The hair loss associated with trichotillomania is patchy and is characterized by broken hairs of varying length. Within the patches, hair loss is not complete. If the hair trauma is not severe or chronic enough to cause scarring, the child's hair usually regrows when the trauma ceases.

Telogen effluvium, another common cause of hair loss, affects both children and adults. This condition is responsible for more hair loss than any other cause except adult male-pattern baldness. In telogen effluvium, there is a physiologic basis to the hair loss; something happens to interrupt the hair's normal growth cycle and to drive many or all of the hairs into the telogen phase. Between six and 16 weeks later, partial or complete baldness occurs.

Many factors can cause telogen effluvium, including the following:

• high fever
• medications, including chemotherapy
• crash diets
• excessive vitamin A
• emotional stress
• surgery
• severe injury

In the telogen phase, a child's hair undergoes growth spurts and pauses. During the rest phase between spurts, the bulb at the end of the hair root decreases in volume and the hair loosens. Although exaggerated during adolescence , particularly in girls (due the influence of female hormones), even preadolescents may experience excessive hair loss on a daily basis. The scalp hair, however, appears normal in this condition.

When to call the doctor

It is important to consult a dermatologist or pediatrician if a child sheds hair in large amounts (more than 100 hairs per day for longer than four weeks) after combing, brushing, or shampooing or if the hair becomes significantly thinner. Also, if a child's scalp show signs of infection (redness, swelling, tenderness, warmth), consulting a physician is advised.

If children are observed pulling out their hair, eyelashes, or eyebrows, parents should consult a physician in order to determine the underlying cause of the habit.

Diagnosis

Because hair loss is caused by a variety of conditions, a physician diagnoses the cause of the child's hair loss based on medical history, family history of hair loss, medications (including vitamins ), nutritional status, hair-care habits, and a physical examination.

If the physician suspects a fungal infection of the scalp, a hair sample may be tested by microscopic examination in the laboratory. Microscopic examination of a hair plucked at the periphery of the hair loss area often reveals a characteristic disruption of the integrity of the hair shaft. The infection may be confirmed by culturing the scalp for fungal organisms.

Blood tests or a scalp biopsy may be required if a medical condition—such as lupus erythematosus, thyroid dysfunction, iron deficiency, or hormonal imbalance—is suspected.

Treatment

Treatment varies with the cause of the hair loss. In some cases, early treatment is important in restoring the hair. Often congenital and hereditary hair loss and hair shaft abnormalities, however, have no effective treatment.

For fungal infections such as tinea capitis, treatment usually requires a systemic approach with an oral anti-fungal prescription medication such as griseofulvin (Fulvicin). This medication, which must be taken for four to eight weeks, is very effective in curing the infection and restoring the hair. Early treatment is important in preventing possible permanent hair loss.

Topical creams or antifungal shampoos containing 2 percent ketoconazole are often used two to three times per week for eight weeks. Although shampoos and topical antifungal creams may decrease scaling, the infection usually returns because these products do not penetrate the hair follicle deeply enough to eradicate the infection.

A wide variety of treatments are available for alopecia areata. There has been some success with use of medications that suppress the immune system, including dinitrochlorobenzene (DNCB) and diphenylcycloprope-none (DPCP). The side effects of these drugs, however, may outweigh the benefits for a disease that most often resolves on its own.

In addition, topical creams or lotions such as minoxidil, cortisone (also injected into the scalp), or anthralin are sometimes used. Because such treatment triggers hair growth in bald patches but does not eradicate the disease, however, new bald patches can occur in other parts of the scalp even if new growth occurs.

Hair loss resulting from telogen effluvium or drug side effects usually requires no treatment. Hair loss from poor nutrition or medical illness usually stops with the adoption of a healthy diet and treatment of the underlying medical condition. Once the stressful event is over, complete hair growth usually occurs within six months.

Alternative treatment

There is some evidence to suggest that aromatherapy is a safe and effective treatment for alopecia areata. Aromatherapy involves rubbing scented essential oils into the skin to treat localized and systemic disease.

Massaging the essential oils of rosemary, lavender, sage, thyme, and cedar into the scalp is believed to increase circulation and reduce stress. About three to six drops of essential oil are added to 1 tablespoon of jojoba or grape seed oil and massaged into the scalp.

In addition to aromatherapy, stress reduction techniques such as yoga , meditation, or creative visualization may increase blood flow to the scalp and stimulate hair growth.

Prognosis

The prognosis for children with alopecia varies with the cause of hair loss. Certain types of alopecia respond more readily to treatment. For example, hair loss in telogen effluvium usually occurs over several weeks to months, then stops. Hair then grows back over the next several months.

Overall, the outlook for children with alopecia areata is good. Alopecia areata usually resolves with time, although alopecia totalis is less likely to remit. With appropriate treatment, from 60 percent to 95 percent of children regrow all of their hair within one year.

Early treatment and the proper antifungal medications can cure tinea capitis, although patience is required because the condition may take several months to resolve.

Prevention

Although it may not be possible to prevent all types of alopecia—such as alopecia areata or hair loss associated with medical conditions—certain forms of hair loss may be prevented. Highly contagious fungal infections such as tinea capitis, for example, may be prevented by keeping hair clean and by teaching children not to share hats, combs, or hair brushes. In addition, adolescent girls should be cautioned not to share makeup.

It is important to teach children and adolescents to handle their hair with care, especially when shampooing, drying, brushing, combing, braiding, and using chemical processes. Hair is more fragile when it is wet, so vigorous towel drying and rough combing and brushing should be avoided. Wide-toothed combs and brushes with smooth tips are recommended.

Nutritional concerns

Children may experience hair loss or excessive thinning as a result of certain nutritional deficiencies. To prevent such hair loss, it is essential to include B-6, biotin, and folic acid—either in the diet or in supplement form.

KEY TERMS

Bulb —The hair bulb is the expanded portion on the lower end of the hair root.

Epidermis —The outermost layer of the human skin.

Follicle —A pouch-like depression.

Keratin —A tough, nonwater-soluble protein found in the nails, hair, and the outermost layer of skin. Human hair is made up largely of keratin.

Shaft —The portion of the hair that extends from the follicle and goes beyond the surface of the epidermis.

It has been found that certain minerals , including magnesium, sulfur, silica, and zinc are also important for maintaining healthy hair. Beta-carotene, which is converted to vitamin A in the body, is also essential to healthy skin, hair, and nails. Beta-carotene is found in green and yellow vegetables and fruits.

Because hair is composed of protein, a diet that is too low in protein may cause hair thinning or a disruption of the growth cycle. Thus eating a protein-rich diet often results in improved hair growth. In addition to lean meat, good food sources of protein include fish, eggs, dairy products, and beans.

Parental concerns

Because society has placed so much emphasis on appearance, hair loss, particularly if it is severe, may be emotionally devastating to children and adolescents. Hair loss can lead to embarrassment, low self-esteem , and depression. Thus it is important for parents to consult a physician as soon as possible to minimize not only the physical but also the emotional impact of hair loss on their child.

See also Dermatitis; Malnutrition; Trichotillomania.

Resources

BOOKS

"Disorders of Hair." In Nelson Textbook of Pediatrics, 17th ed. Edited by Richard E. Behrman, Robert M. Kliegman, and Hal B. Jenson. Philadelphia: Saunders, 2004.

Powell, Jennifer, Natalie Stone, and Rodney P. R. Dawber. An Atlas of Hair and Scalp Diseases. Carnforth, UK: Parthenon, 2000.

PERIODICALS

Usatine, Richard P. "Bald Spots on a Young Girl." Journal of Family Practice 53, no. 1 (January 2004): 33–36.

ORGANIZATIONS

American Academy of Dermatology. PO Box 4014, Schaumburg, IL 60168–0050. Web site: <www.aad.org>.

American Hair Loss Council. 125 Seventh Street, Suite 625, Pittsburgh, PA 15222. Web site: <www.ahlc.org>.

National Alopecia Areata Foundation. PO Box 150760, San Rafael, CA 94915–0760. Web site: <http://www.naaf.org>.

WEB SITES

Brodell, Robert T., and Giorgio Vescera. "Black Dot Tinea Capitis." Postgraduate Medicine Online 111, no. 4 (April 2002). Available online at <www.postgraduatemedicine.com/issues/2002/04_02/pd_brodell.htm> (accessed October 10, 2004).

Genevieve Slomski, Ph.D.

Alopecia

Definition

Alopecia simply means hair loss (baldness).

Description

Hair loss occurs for a great many reasons, from conditions that make people literally pull it out to complete hair loss caused by the toxicity of cancer chemotherapy. Some causes are considered natural, while others signal serious health problems. Some conditions are confined to the scalp. Others reflect disease throughout the body. Being plainly visible, the skin and its components can provide early signs of disease elsewhere in the body.

Oftentimes, conditions affecting the skin of the scalp will result in hair loss. The first clue to the specific cause is the pattern of hair loss, whether it be complete baldness (alopecia totalis), patchy bald spots, thinning, or hair loss confined to certain areas. Also a factor is the condition of the hair and the scalp beneath it. Sometimes only the hair is affected; sometimes the skin is visibly diseased as well.

Causes and symptoms

• Male pattern baldness (androgenic alopecia) is considered normal in adult males. It is easily recognized by the distribution of hair loss over the top and front of the head and by the healthy condition of the scalp.

• Alopecia areata is a hair loss condition of unknown cause that can be patchy or extend to complete baldness.
• Fungal infections of the scalp usually cause patchy hair loss. The fungus, similar to the ones that cause athlete's foot and ringworm, often glows under ultraviolet light.
• Trichotillomania is the name of a mental disorder that causes a person to pull out his or her own hair.
• Complete hair loss is a common result of cancer chemotherapy, due to the toxicity of the drugs used.
• Systemic diseases often affect hair growth either selectively or by altering the skin of the scalp. One example is thyroid disorders. Hyperthyroidism (too much thyroid hormone) causes hair to become thin and fine. Hypothyroidism (too little thyroid hormone) thickens both hair and skin.
• Several autoimmune diseases (when protective cells begin to attack self cells within the body) affect the skin, notably lupus erythemematosus.
• In 2004, a report a the annual meeting of the American Academy of Dermatology said that alopecia was becoming nearly epidemic among black women as a result of some hairstyles that pull too tightly on the scalp and harsh chemical treatments that damage the hair shaft and follicles.

Diagnosis

Dermatologists are skilled in diagnosis by sight alone. For more obscure diseases, they may have to resort to a skin biopsy, removing a tiny bit of skin using a local anesthetic so that it can be examined under a microscope. Systemic diseases will require a complete evaluation by a physician, including specific tests to identify and characterize the problem.

Treatment

Successful treatment of underlying causes is most likely to restore hair growth, be it the completion of chemotherapy, effective cure of a scalp fungus, or control of a systemic disease. Two relatively new drugs—minoxidil (Rogaine) and finasteride (Proscar)—promote hair growth in a significant minority of patients, especially those with male pattern baldness and alopecia areata. While both drugs have so far proved to be quite safe when used for this purpose, minoxidil is a liquid that is applied to the scalp and finasteride is the first and only approved treatment in a pill form.

KEY TERMS

Athlete's foot— A fungal infection between the toes, officially known as tinea pedis.

Autoimmune disease— Certain diseases caused by the body's development of an immune reaction to its own tissues.

Chemotherapy— The treatment of diseases, usually cancer, with drugs (chemicals).

Hair follicles— Tiny organs in the skin, each one of which grows a single hair.

Lupus erythematosus— An autoimmune disease that can damage skin, joints, kidneys, and other organs.

Ringworm— A fungal infection of the skin, usually known as tinea corporis.

Systemic— Affecting all or most parts of the body.

Minoxidil was approved for over-the-counter sales in 1996. When used continuously for long periods of time, minoxidil produces satisfactory results in about one-fourth of patients with androgenic alopecia and as many as half the patients with alopecia areata. There is also an over-the-counter extra-strength version of minoxidil (5% concentration) approved for use by men only. The treatment often results in new hair that is thinner and lighter in color. It is important to note that new hair stops growing soon after the use of minoxidil is discontinued.

Over the past few decades a multitude of hair replacement methods have been performed by physicians and non-physicians. They range from simply weaving someone else's hair in with the remains of one's own to surgically transplanting thousands of hair follicles one at a time.

Hair transplantation is completed by taking tiny plugs of skin, each containing one to several hairs, from the back side of the scalp. The bald sections are then implanted with the plugs. Research completed in 2000 looked at the new technique of hair grafting, and found that micrografts (one or two hairs transplanted per follicle) resulted in fewer complications and the best results.

Another surgical procedure used to treat androgenic alopecia is scalp reduction. By stretching skin, the hairless scalp can be removed and the area of bald skin decreased by closing the space with hair-covered scalp. Hair-bearing skin can also be folded over an area of bald skin with a technique called a flap.

Stem cell research is generating new hope for baldness. Scientists know that a part of the hair follicle called the bulge contains stem cells that can give rise to new hair and help heal skin wounds. Early research with mice in 2004 showed promise for identifying the genes that cause baldness and to identify drugs that can reverse the process.

Prognosis

The prognosis varies with the cause. It is generally much easier to lose hair than to regrow it. Even when it returns, it is often thin and less attractive than the original.

Resources

PERIODICALS

Cohen, Philip. "Stem Cells Generate Hair and Hope for the Bald." New Scientist (March 20, 2004): 17.

Lohr, Elizabeth. "Alopecia Nearly Epidemic Among Black Women." Clinical Psychiatry News (March 2004): 96.

Nielsen, Timothy A., and Martin Reichel. "Alopecia: Diagnosis and Management." American Family Physician.

OTHER

Androgenetic Alopecia.com. "How can minoxidil be used to treat baldness?" May1, 2001. 〈http://androgenetic-alopecia.com/baldnesstreatments/minoxidil/002minoxidilbaldnessusee.shtml〉.

Mayo Clinic. "Alopecia" January 26, 2001. [cited May 1, 2001]. 〈http://www.mayohealth.org〉.

WebMD Medical News. "Hair Today, Gone Tomorrow, Hair Again" 2000. [cited May 1, 2001]. 〈http://my.webmd.com/content/article/1728.53923〉.

Alopecia

Description

Alopecia, also called hair loss, baldness, and epilation, is a common side effect of chemotherapy and radiation therapy . Most patients undergoing chemotherapy, especially those who are being treated with more than one drug, will suffer from hair loss. Radiation therapy causes hair loss only in the area of skin being treated.

Although most often associated with head hair, alopecia can occur on any part of the body. Cancer treatments can also cause hair on the face (including the eyelashes and eyebrows), genitals, underarms, and body to fall out.

Alopecia usually occurs between two and three weeks after the first treatment. Most often, hair loss is gradual and occurs over a three-to-four week period. However, the chemotherapy drug paclitaxel can cause all the hair of the body to fall out within a 24-hour period. Loss of head hair usually begins on the top (crown) and sides of the head, presumably due to friction caused by pillows, bed linens, and hats.

Alopecia caused by chemotherapy is usually temporary. Hair loss caused by radiation therapy may be permanent. Hair regrows in about three to five months. Regrown hair may be a different color or type than before treatment.

Although alopecia is a harmless, painless condition, it can significantly affect body image , self esteem, and sexuality . As a result, alopecia may cause the patient to limit social activities. Hair loss can also cause depression .

Causes

To understand the cause of alopecia, it is helpful to understand how hair grows. Hair grows out of microscopic depressions in the skin called hair follicles. Normally, there are about 100, 000 hairs on a person's head (scalp). Each hair is in one of three different growth stages. Eighty-eight percent of the hair on the head is in the growing (anagen) stage, which lasts for two to five years. Some of the hairs are no longer growing and are in a resting (telogen) stage. The telogen stage lasts for three to five months. The transitional (catagen) stage lies in between the growing and resting stages. At the end of the telogen stage, the hair falls out. Usually about 100 hairs fall out each day. Alopecia becomes noticeable only after about half of the hairs have fallen out.

Chemotherapy-induced alopecia

Chemotherapy drugs kill the rapidly growing cancer cells. However, certain normal cells of the body are rapidly growing and they, too, are affected by the chemotherapy drugs. Rapidly growing cells are found in the base of the hair (hair bulb), as well as other parts of the body. When the drug kills the cells of the hair bulb, the hair falls out. Alternatively, the drug affects the hair bulb, causing the hair to narrow. This weakened hair is prone to breakage during normal brushing or shampooing.

Although many chemotherapy drugs can cause alopecia, certain ones are highly prone to causing hair loss. In addition, the way in which the drug is administered, the dose, and the treatment schedule can all influence the ability of a drug to cause alopecia. For instance, the fast administration of large doses of drug (bolus-dosing) is more toxic to the hair bulb than administering lower doses more slowly. Chemotherapy drugs with a very high potential to cause alopecia include:

• cyclophosphamide
• daunorubicin
• doxorubicin (at doses higher than 50 mg)
• etoposide
• ifosamide
• paclitaxel
• docetaxel

Radiation-induced alopecia

Like chemotherapy, radiation kills rapidly dividing cells. Hair loss occurs only at the site where radiation is applied. High doses of radiation (greater than 6, 000 cGy) usually causes permanent damage to hair follicles preventing hair from regrowing. If hair regrowth occurs, the hairs may be finer than before radiation therapy. However, hair usually regrows following low doses of radiation (less than 6, 000 cGy).

Treatments

Methods to prevent chemotherapy-induced alopecia exist, although their safety and effectiveness remain questionable. One method puts pressure on the scalp (scalp tourniquet) to block blood flow, thereby preventing the drugs from damaging the hair follicles. Another method uses ice or cooling devices (scalp hypothermia) to decrease the amount of drug taken up by the hair cells. Lastly, certain medications have been used to prevent alopecia.

Alopecia resulting from cancer treatment is unavoidable and no treatments for it are available. Patients are encouraged to buy a wig before their hair falls out so that a good color and texture match can be made and the wig will be available when needed. Patients with long hair can have a wig made with their own hair. If a wig is covered by insurance, a doctor's prescription would be required to make an insurance claim. Some patients prefer to shave their head once hair loss begins.

Things that a cancer patient can do to treat an irritated and red scalp and minimize hair loss include:

• using a mild shampoo
• using hair brushes with soft bristles
• avoiding the use of hair dryers, hot curlers, and curling irons
• using the lowest setting on a hair dryer (if a dryer must be used)
• avoiding hair dyes
• avoiding permanent wave solutions
• wearing sunscreen or a hat when outdoors
• using a satin pillowcase

Alternative and complementary therapies

Patients suffering from alopecia may benefit from taking certain vitamins and minerals that promote healthy hair. These include zinc, selenium, magnesium, iron; and vitamins A, B-complex, C, and E. Vitamin E may be massaged into the scalp. Also, evening primrose oil and flaxseed oil are rich sources of omega-3 and omega-6 fatty acids, which are important for healthy hair.

Chinese medicinal herbs that promote hair growth include cornus, Chinese foxglove root, Chinese yam, lycium fruit, and polygonum. Herbalists recommend rinsing hair with sage tea or massaging the scalp with essential oil of rosemary to improve blood circulation and stimulate hair follicles.

It is important that patients check with their oncologist prior to taking any vitamin, mineral, or medicinal herb supplements as there is a possibility they may interfere with the effectiveness of the chemotherapy treatments.

Resources

BOOKS

De Vita, Vincent, Samuel Hellman, and Steven Rosenberg, eds. Cancer, Principles & Practice of Oncology, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2000. <http://www.LWWoncology.com>

Maleskey, Gale. Nature's Medicines: from Asthma to Weight Gain, from Colds to High Cholesterol—The Most Powerful All-Natural Cures. Emmaus, PA: Rodale Press, Inc., 1999.

Somerville, Robert, ed. The Medical Advisor. Alexandria, VA:Time-Life Books, 2000.

Yarbro, Connie Henke, Michelle Goodman, Margaret Hansen Frogge, and Susan L. Groenwald, eds. Cancer Nursing, Principles and Practice, 5th ed. Sudbury, MA: Jones and Bartlett Publishers, 2000.

Yarbro, Connie Henke, Margaret Hansen Frogge, and Michelle Goodman, eds. Cancer Symptom Management, 2nd ed. Sudbury, MA: Jones and Bartlett Publishers, 1999.

PERIODICALS

Dorr, Victoria J. "A Practitioner's Guide to Cancer-Related Alopecia." Seminars in Oncology 25, no. 5 (October 1998): 526-570.

OTHER

"How Do I Deal With Hair Loss?" American Cancer Society, Inc. 2000. 28 June 2001 <http://www3.cancer.org/cancerinfo>.

Belinda Rowland, Ph.D.

KEY TERMS

Anagen stage

—The growing stage in the growth cycle of hair.

Catagen stage

—The intermediate stage in the hair-growth cycle during which proliferation ceases and regression of the hair follicle occurs.

Hair bulb

—The base of a hair where living cells multiply causing the hair to grow.

Hair follicle

—The depression in skin where a hair originates.

Scalp tourniquet

—A process to prevent chemotherapy-induced alopecia in which a tight band is applied to the head.

Telogen stage

—The resting stage in the growth cycle of hair.

Alopecia

Definition

Alopecia simply means hair loss (baldness).

Description

Hair loss occurs for a great many reasons, from conditions that make people literally pull it out to complete hair loss caused by the toxicity of cancer chemotherapy . Some causes are considered natural, while others signal serious health problems. Some conditions are confined to the scalp. Others reflect disease throughout the body. Being plainly visible, the skin and its components can provide early signs of disease elsewhere in the body.

Oftentimes, conditions affecting the skin of the scalp will result in hair loss. The first clue to the specific cause is the pattern of hair loss, whether it be complete baldness (alopecia totalis), patchy bald spots, thinning, or hair loss confined to certain areas. Also a factor is the condition of the hair and the scalp beneath it. Sometimes only the hair is affected; sometimes the skin is visibly diseased as well.

Causes and symptoms

• Male pattern baldness (androgenic alopecia) is considered normal in adult males. It is easily recognized by the distribution of hair loss over the top and front of the head and by the healthy condition of the scalp.
• Alopecia areata is a hair loss condition of unknown cause that can be patchy or extend to complete baldness.
• Fungal infections of the scalp usually cause patchy hair loss. The fungus, similar to the ones that cause athlete's foot and ringworm, often glows under ultraviolet light.
• Trichotillomania is the name of a mental disorder that causes a person to pull out his or her own hair.
• Complete hair loss is a common result of cancer chemotherapy, due to the toxicity of the drugs used.
• Systemic diseases often affect hair growth either selectively or by altering the skin of the scalp. One example is thyroid disorders. Hyperthyroidism (too much thyroid hormone) causes hair to become thin and fine. Hypothyroidism (too little thyroid hormone) thickens both hair and skin.
• Several autoimmune diseases (when protective cells begin to attack self cells within the body) affect the skin, notably lupus erythemematosus.
• In 2004, a report a the annual meeting of the American Academy of Dermatology said that alopecia was becoming nearly epidemic among black women as a result of some hairstyles that pull too tightly on the scalp and harsh chemical treatments that damage the hair shaft and follicles.

Diagnosis

Dermatologists are skilled in diagnosis by sight alone. For more obscure diseases, they may have to resort to a skin biopsy, removing a tiny bit of skin using a local anesthetic so that it can be examined under a microscope. Systemic diseases will require a complete evaluation by a physician, including specific tests to identify and characterize the problem.

Treatment

Successful treatment of underlying causes is most likely to restore hair growth, be it the completion of chemotherapy, effective cure of a scalp fungus, or control of a systemic disease. Two relatively new drugs—minoxidil (Rogaine) and finasteride (Pros-car)—promote hair growth in a significant minority of patients, especially those with male pattern baldness and alopecia areata. While both drugs have so far proved to be quite safe when used for this purpose, minoxidil is a liquid that is applied to the scalp and finasteride is the first and only approved treatment in a pill form.

Minoxidil was approved for over-the-counter sales in 1996. When used continuously for long periods of time, minoxidil produces satisfactory results in about one-fourth of patients with androgenic alopecia and as many as half the patients with alopecia areata. There is also an over-the-counter extra-strength version of minoxidil (5% concentration) approved for use by men only. The treatment often results in new hair that is thinner and lighter in color. It is important to note that new hair stops growing soon after the use of minoxidil is discontinued.

KEY TERMS

Athlete's foot —A fungal infection between the toes, officially known as tinea pedis.

Autoimmune disease —Certain diseases caused by the body's development of an immune reaction to its own tissues.

Chemotherapy —The treatment of diseases, usually cancer, with drugs (chemicals).

Hair follicles —Tiny organs in the skin, each one of which grows a single hair.

Lupus erythematosus —An autoimmune disease that can damage skin, joints, kidneys, and other organs.

Ringworm —A fungal infection of the skin, usually known as tinea corporis.

Systemic —Affecting all or most parts of the body.

Over the past few decades a multitude of hair replacement methods have been performed by physicians and non-physicians. They range from simply weaving someone else's hair in with the remains of one's own to surgically transplanting thousands of hair follicles one at a time.

Hair transplantation is completed by taking tiny plugs of skin, each containing one to several hairs, from the back side of the scalp. The bald sections are then implanted with the plugs. Research completed in 2000 looked at the new technique of hair grafting, and found that micrografts (one or two hairs transplanted per follicle) resulted in fewer complications and the best results.

Another surgical procedure used to treat androgenic alopecia is scalp reduction. By stretching skin, the hairless scalp can be removed and the area of bald skin decreased by closing the space with hair-covered scalp. Hair-bearing skin can also be folded over an area of bald skin with a technique called a flap.

Stem cell research is generating new hope for baldness. Scientists know that a part of the hair follicle called the bulge contains stem cells that can give rise to new hair and help heal skin wounds. Early research with mice in 2004 showed promise for identifying the genes that cause baldness and to identify drugs that can reverse the process.

Prognosis

The prognosis varies with the cause. It is generally much easier to lose hair than to regrow it. Even when it returns, it is often thin and less attractive than the original.

Resources

PERIODICALS

Cohen, Philip. “Stem Cells Generate Hair and Hope for the Bald.” New Scientist (March 20, 2004): 17.

Lohr, Elizabeth. “Alopecia Nearly Epidemic Among Black Women.” Clinical Psychiatry News (March 2004): 96.

Nielsen, Timothy A., and Martin Reichel. “Alopecia: Diagnosis and Management.” American Family Physician.

OTHER

Androgenetic Alopecia.com. “How can minoxidil be used to treat baldness?” April 20, 2008. http://androgeneticalopecia.com/baldnesstreatments/minoxidil/002minox-idilbaldnessusee.shtml.

Mayo Clinic. “Alopecia” January 26, 2001. [cited April 20, 2008]. http://www.mayohealth.org.

WebMD Medical News. “Hair Today, Gone Tomorrow, Hair Again” 2000. [cited April 20, 2008]. http://my.webmd.com/content/article/1728.53923.

Beth A. Kapes

Teresa G. Odle

Alopecia The medical term for baldness. Well known, and varying in onset, in the course of ageing. It also occurs, less irrevocably, due to skin damage or disease or to the side-effects of chemotherapy or radiotherapy in the treatment of cancer. The cells at the base of the hair follicles of the scalp, which normally keep on manufacturing new keratinous substance to add to the root of the hair, die or cease to function; the hair therefore falls out and is not replaced, until or unless that cellular function is restored. Alopecia may extend beyond the scalp to other body hair. Alopecia areata is a chronic condition of patchy baldness.

Stuart Judge