Skin Conditions

Leaves of Three, Let Them Be

What Does the Skin Do?

What Can Go Wrong?

What Are Some Common Skin Problems?

How Are Skin Conditions Diagnosed?

How Are Skin Conditions Treated?

The Skinny on Skin Care

Resources

Skin conditions include various rashes, diseases, infections, injuries, growths, and cancers that affect the skin.

KEYWORDS

for searching the Internet and other reference sources

Birthmarks

Dermatitis

Eczema

Herpes

Melanoma

Moles

Rash

Leaves of Three, Let Them Be

Alison loved to take long walks in the woods in the summer, but one day she developed a streaky rash two days after she had gone on a hike. At first, her skin was red and swollen in spots. Soon, however, little blisters formed and began to itch intensely. Alison had developed a rash from poison ivy. Her mother warned her not to scratch, because her fingernails might carry germs that could cause an infection. It was hard to resist, but cool showers and a soothing lotion helped. Within a few days, the blisters began to scab over. It took about 10 days for the rash to heal completely. Afterward, Alison was careful to wear long-sleeved shirts and long pants when walking in the woods and to stay away from poison ivy, identifiable by its clusters of three leaves.

What Does the Skin Do?

The skin is the largest and most visible organ of the body. It also is one of the most complex, because it has so much to do. The main job of the skin is to protect a person’s inside parts from the outside world. It acts as a shield against sun, wind, heat, cold, dryness, pollution, and cigarette smoke. All of these things can injure the skin over time. In addition, the skin comes into contact with and helps protect the body from germs; allergens (AL-er-jens), which are substances that can cause allergic reactions; and irritants, which are harsh chemicals that can hurt the skin. In addition, special nerve endings in the skin alert the brain to heat, cold, and pain.

Skin Deep

• The average adult body has two square yards of skin, which make up about 15 percent of the body’s total weight.
• A one-inch square of skin contains millions of cells as well as many special nerve endings for sensing heat, cold, and pain.
• The average thickness of skin is one-tenth of an inch, but it ranges from very thin on the eyelids to thick on the soles of the feet.

What Can Go Wrong?

It is not surprising that many things can go wrong with an organ so big and complicated. Allergens and irritants can make the skin break out in a rash. Dermatitis (der-ma-TY-tis) is a general term for red, inflamed skin from a variety of causes.

There also can be glitches in the way the skin works. For example, it can make too much oil, leading to acne (AK-nee). If the skin makes too many new cells, the result can be psoriasis (so-RY-a-sis). If the skin makes too little or too much coloring matter, called pigment, the result can be patches of abnormally light skin (hypopigmentation) or dark skin (hyperpigmentation).

The skin also can be affected by injuries, such as sunburn, and by viral infections, such as cold sores. Other kinds of skin infections are caused by bacteria and fungi. In addition, the skin can be affected by both noncancerous growths, such as birthmarks, and skin cancers.

What Are Some Common Skin Problems?

These are some of the most common skin problems seen by dermatologists (der-ma-TOL-o-jists), doctors who specialize in treating skin problems:

• Acne: pimples, blackheads, whiteheads, and deeper lumps. Almost all teenagers have at least a little acne, and some adults have the problem as well. Acne develops when the skin makes too much oil and sheds dead cells too fast. Bacteria also plays a role.
• Athlete’s foot: a fungal infection that may cause the skin on the foot to look red and peel, crack, flake, or even blister. Sweaty feet and tight shoes provide the perfect setting for a fungus to grow. Athlete’s foot is most common among teenagers and adult men.
• Atopic (ay-TOP-ik) dermatitis, also called eczema (EK-zem-ah): a red, itchy rash that often runs in families and accompanies allergies. In babies, it typically leads to itching, oozing patches with scabs, mainly on the face. In older children, the patches tend to be dry, and the affected skin may flake and thicken. In teenagers, the patches usually occur inside the elbow bends, backs of knees, ankles, wrists, face, neck, and upper chest.
• Birthmarks: a skin mark that develops before or shortly after birth. Several kinds of common birthmarks are caused by overgrowth of blood vessels. Such marks are usually painless.
• Cold sores: an infection caused by the herpes (HER-peez) simplex virus that leads to sores, usually around the mouth and nose. Some sores are barely noticeable, but others hurt. Cold sores are common among children and are easily spread from person to person by kissing or sharing dishes or towels.

BoTox and Wrinkle Relief

One of the drugs in the fight against wrinkles is called BoTox. BoTox, short for Botulism Toxin type A, is a byproduct produced by the bacterium Clostridium botulinum. In food, the bacterium causes a potentially fatal type of food poisoning known as botulism. To remove wrinkles, a small amount of BoTox is injected into the muscles under the wrinkled skin. The BoTox temporarily paralyzes the muscles and restricts their movement. The result, after 3 to 5 days, is that the wrinkles temporarily disappear. This is not a permanent treatment—it must be repeated every 3 months.

• Contact dermatitis: a red, itchy rash that occurs when the skin comes into contact with an allergen or something else to which the skin is sensitive. Examples include poison ivy and sensitivities to nickel, rubber, and skin care products.
• Dandruff: flaking of the skin on the scalp. Some flaking is part of the normal process by which the outer layer of skin cells is regularly shed. If the flaking becomes obvious on a person’s hair and clothes, it is called dandruff. If the scalp is red or if there are large flakes along with flaking elsewhere, the problem may be something else.
• Hives: pale red, swollen bumps that occur in groups on the skin. Hives are usually itchy, but they may also burn or sting. They are caused when the body releases a chemical called histamine (HIS-ta-meen) as part of a reaction to such things as foods, medications, insect bites, infections, cold, or scratching of the skin.
• Irritant dermatitis: a red, itchy rash that occurs when the skin comes into contact with a harsh chemical. Examples of irritants include strong soaps or detergents and industrial chemicals.
• Moles: growths that can appear anywhere on the skin, alone or in groups. They are usually brown and can have various shapes and sizes. Everyone has at least a few moles, and some people have forty or more. Most moles are not cancerous, but some may turn into a serious form of skin cancer called malignant melanoma (mel-a-NO-ma).
• Poison ivy: a common type of contact dermatitis that occurs when a sensitive person comes into contact with a substance found in the sap of poison ivy plants. Poison oak and poison sumac (SOO-mak) plants can have the same effect. The result is a streaky rash with redness and swelling, followed by blisters and itching. About 85 percent of all people will have this kind of allergic reaction to poison ivy.
• Psoriasis: a long-lasting skin disease caused when too many new cells are made, resulting in patches of red, thickened skin covered with silvery flakes. Four to 5 million Americans have psoriasis. It may result from a problem with the immune system, which normally fights germs and other foreign substances in the body.

• Ringworm: a skin infection caused by a fungus (not a worm). Ringworm is marked by red, itchy, ring-shaped patches that may flake or blister. It commonly affects the feet, scalp, trunk, nails, and groin.

Rash Thoughts

These are the medical terms for some common skin spots and bumps:

• Comedo (KOM-ee-do): a blackhead, whitehead, or pimple. Example: acne.
• Macule (MAK-yool): a small, flat, colored spot. Example: freckles.
• Papule (PAP-yool): a small, hard bump. Example: warts.
• Plaque (PLAK): a large, raised patch of skin. Example: psoriasis.
• Pustule (PUS-tyool): a pimple filled with pus. Example: acne.
• Wheal (WEEL): a short-lasting, swollen bump. Example: hives.

• Rosacea (ro-ZAY-she-a): a skin disease that causes redness and swelling on the face that may gradually spread to the cheeks and chin. Small blood vessels and tiny pimples may appear on or around the red area. Fair-skinned adults, especially women, are most likely to get rosacea.
• Seborrheic (seb-o-REE-ik) dermatitis: a common condition that causes red skin and greasy-looking flakes, mainly on the scalp, on the sides of the nose, between the eyebrows, on the eyelids, behind the ears, or on the chest. In babies, this condition is called cradle cap. In adults, it often occurs in people with oily skin and hair, and it may occur in those with acne or psoriasis.
• Shingles: a skin eruption caused by the same virus that causes chickenpox. It starts with pain or tingling on one side of the body or face, followed by a red rash with small blisters. After a person has chickenpox, the virus may live on in the nerve cells and come out years later as shingles. An episode of shingles may last weeks.
• Skin cancer: the most common of all types of cancer, including various kinds of growths on the skin. About 700,000 Americans get skin cancer each year. The main cause is the sun’s harmful rays.
• Sunburn: the immediate result of getting too much sun. The skin is injured, just as if it had been burned by heat, and turns red and painful. If the sunburn is severe, blisters may form. The long-term effects of sun damage include wrinkles, certain skin bumps and spots, and skin cancer.
• Vitiligo (vit-i-LY-go): a condition that causes white patches of skin due to a loss of pigment in the cells and tissues. It affects 1 or 2 out of every 100 people. Although vitiligo strikes people of all races, it is particularly noticeable in those with dark skin.
• Warts: small, hard bumps on the skin or inner linings of the body that are caused by a virus. Most are skin-colored, raised, and rough, but some are dark, flat, or smooth. Warts are common on the fingers, hands, arms, and feet. Some warts occur on the genitals and can be spread during sex.
• Wrinkles: a common sign of skin aging. The main cause of wrinkles is getting too much sun over a lifetime. Cigarette smoking also plays a major role.

How Are Skin Conditions Diagnosed?

Nearly everyone has a skin problem at some point in life. Such problems can affect anyone, from newborns to older adults. A doctor can identify many skin problems just by looking closely at the skin. The doctor may also ask about the person’s current symptoms, past illnesses, and family history.

In some cases, the doctor may need to do a biopsy (BY-op-see). This involves removing a small bit of skin so that it can be looked at under a microscope. If an infection caused by a fungus is suspected, the doctor may scrape off some skin flakes, which can be checked at a lab for signs of fungus. Another way to check for an infection caused by bacteria or a fungus is with a culture. This involves taking a sample from the site of possible infection and placing it in a nourishing substance called a medium to see what kind of bacteria or fungi grow.

If contact or allergic dermatitis is suspected, the doctor may do patch testing to find out what allergens are to blame. This involves putting tiny amounts of different substances on the skin under a patch. The skin is checked 2 days later to see which substances, if any, caused a reaction.

How Are Skin Conditions Treated?

• Medicines: Many medicines used to treat mild skin conditions are sold without a prescription in creams, lotions, gels, pads, and shampoos. Stronger medicines that are put on the skin, taken by mouth, or given in a shot are available only from a doctor or with a doctor’s prescription.
• Surgery: Doctors use several kinds of surgery to remove or destroy abnormal skin tissue. Excision involves removing a skin growth by cutting. Cryosurgery involves destroying a skin growth by freezing it with an extremely cold liquid such as liquid nitrogen. Electrosurgery involves destroying a skin growth by burning it with electricity. Laser surgery involves destroying skin tissue with a laser—a tool that produces a very narrow and intense beam of light. Surgery is used for such things as warts, skin cancer, moles, and birthmarks.
• Light therapy: Doctors treat certain skin problems with lamps that give off ultraviolet rays. In some cases, the person also takes a drug that makes the skin more sensitive to ultraviolet light. This therapy is used for such things as psoriasis and vitiligo.

The Skinny on Skin Care

These tips can help keep a person’s skin feeling healthy and looking its best:

• Protect the skin from the sun’s harmful rays. Avoid the midday sun, cover up with clothing, and use a good sunscreen with an SPF of 15 or higher.
• Wash the face gently with lukewarm water, a mild soap, and a washcloth or sponge to remove dead cells.
• Reduce dry skin by keeping baths short and using warm water. Use soap only as needed on the face, underarms, genitals, hands, and feet.
• Dry off the skin after bathing by brushing it lightly with the hands or patting it with a towel.

See also

Acne

Albinism

Allergies

Athlete’s Foot

Hives

Psoriasis

Ringworm

Skin Cancer

Vitiligo

Warts

Resources

Book Chapter

“Chapter 30. Your Skin.” In: David E. Larson, editor. Mayo Clinic Family Health Book, 2nd edition. New York: William Morrow, 1996.

Organizations

American Academy of Dermatology, P.O. Box 681069, Schaumburg, IL 60168-1069, (888) 462-DERM. A group of doctors who treat skin diseases. http://www.aad.org

American Society for Dermatologic Surgery, 930 N. Meacham Road, Schaumburg, IL 60173, (800) 441-2737. A group of doctors who do surgery on the skin. http://www.asds-net.org

National Institute of Arthritis and Musculoskeletal and Skin Diseases, 1 AMS Circle, Bethesda, MD 20892-3675, (301) 495-4484. A federal agency that studies skin diseases. http://www.nih.gov/niams

Skin and Soft Tissue Infections

What Causes Skin and Soft Tissue Infections?

What Are Some Types of Skin and Soft Tissue Infections?

Are Skin and Soft Tissue Infections Contagious?

How Are Skin and Soft Tissue Infections Diagnosed?

Can Skin and Soft Tissue Infections Be Prevented?

Resources

Skin and soft tissue infections are infections involving the layers of the skin and the soft tissues beneath it.

KEYWORDS

for searching the Internet and other reference sources

Abscesses

Boils

Carbuncles

Cellulitis

Dermatology

Dermatophytes

Furuncles

Impetigo

Molluscum contagiosum

Necrotizing fasciitis

Ringworm

Tinea

Warts

What Causes Skin and Soft Tissue Infections?

Viruses, bacteria, and fungi generally cause skin and soft tissue infections by entering the body at a spot where a cut, scrape, bite, or other wound has broken the skin; some infections are even the result of bacteria that normally live on the body. These infections can affect the layers of the skin or deeper tissues, such as muscle and connective tissue (the interlacing framework of tissue that forms ligaments, tendons, and other supporting structures of the body), and they may bring about symptoms in other parts of the body.

Many infections like varicella (chicken pox) and measles (rubeola) affect the skin, but these infections involve the whole body and do not primarily arise within the skin or soft tissues.

What Are Some Types of Skin and Soft Tissue Infections?

Dermatophyte infections

Dermatophytes (dur-MAH-toh-fites) are fungi that live on the dead outer layer of skin. Sometimes they can produce symptoms of infection. Tinea (TIH-nee-uh) infections, commonly called ringworm (although they have nothing to do with worms), usually are caused by the Trichophyton group of these organisms. They include tinea pedis (PEE-dis), or athlete’s foot; tinea cruris (KRU-ris), or jock itch; tinea capitis (KAH-pih-tis), or ringworm of the scalp; tinea unguium (UN-gwee-um), or ringworm of the nails; and tinea corporis (KOR-poor-us), or ringworm of the body. Damaged skin is more vulnerable to infection, as is skin in warm, moist areas of the body. When the fungus takes hold, it typically causes a ring-like rash of red, flaking skin. The border of the rash may be raised, as if a worm were under the skin. The rash’s shape and this raised edge led people to call the infection ringworm. When the nails are infected, they usually become yellow, thickened, and brittle.

Tinea versicolor, or pityriasis (pih-tih-RYE-uh-sis) versicolor, is caused by the fungus Malassezia furfur. Symptoms include scaly patches of skin, ranging in color from light to dark. The patches occur on the chest, neck, back, underarms, and upper arms. Hot, humid weather encourages the growth of tinea versicolor. These fungal skin infections typically are treated with antifungal creams or ointments. In severe cases or when the infections do not improve with this therapy, several antifungal medications are available that may be given by mouth.

Impetigo

Impetigo (im-pih-TEE-go) refers to a skin infection in which there are red blister-like bumps that contain a yellowish fluid or pus*. After the blisters break open, they crust over. Impetigo is most common on the face, especially around the nose and mouth. Usually, either streptococcus (strep-tuh-KAH-kus) or staphylococcus (stah-fih-lo-KAH-kus) bacteria are the cause of the infection. Impetigo can spread easily, especially among children, who may scratch the lesions and then touch other areas of their skin or another person. People also can contract impetigo from handling clothing or blankets that have been in contact with infected skin.

*pus

is a thick, creamy fluid, usually yellow or greenish in color, that forms at the site of an infection. Pus contains infection-fighting white cells and other substances.

Doctors prescribe antibiotics to treat impetigo. The infection generally clears up without leaving permanent skin damage.

Skin abscesses

Skin abscesses (AB-seh-sez) may occur in areas of the skin where the body has been fighting a bacterial infection. To isolate the infection, the body forms a wall of tissue around the collection of pus, and this area is the abscess. Abscesses are usually round, raised, and red, and they may feel warm and tender. A furuncle (FYOOR-ung-kul), or boil, is an abscess that forms at the base of a hair follicle*. A carbuncle (KAR-bung-kul) forms when the infection spreads to include several follicles and the surrounding skin and deeper tissues. Like furuncles, carbuncles are red, raised, and sore to the touch.

*hair follicle

(FAH-lih-kul) is the skin structure from which hair develops and grows.

Most skin abscesses eventually burst to allow the pus to drain out, but treatment with antibiotics may be needed to clear up the infection in some cases. Skin abscesses that do not improve on their own need to be lanced (punctured and drained) by a doctor.

Cellulitis

Cellulitis (sel-yoo-LYE-tis) is an inflammation of the skin and/or the tissues beneath it. The culprits behind the infection are almost always group A streptococcus or Staphylococcus aureus (stah-fihlo-KAH-kus ARE-ree-us) bacteria. Cellulitis may occur in people with diabetes* or those who have immune system problems even if they do not have a skin injury. The infection can occur anywhere on the body, but it is found most frequently on the face and lower legs. It appears as tender, red, swollen areas of skin. The skin in the infected area may feel stretched and warm. A few days after the first symptoms, patients may experience fever, chills, and muscle aches. Red streaks also may appear on the skin, signaling the spread of the infection.

*diabetes

(dye-uh-BEE-teez) is a condition in which the body’s pancreas does not produce enough insulin or the body cannot use the insulin it makes effectively, resulting in increased levels of sugar in the blood. This can lead to increased urination, dehydration, weight loss, weakness, and a number of other symptoms and complications related to chemical imbalances within the body.

Antibiotics are used to treat cellulitis. Even after the infection is gone, the skin may look different for several weeks. Complications are rare, but they can include sepsis*, gangrene*, and lymphangitis*. Cellulitis may involve infection of deeper tissue called the fascia (FAY-she-uh). Infection in this layer can be very serious or even life threatening and often requires surgery to remove the infected tissue.

*sepsis

is a potentially serious spreading of infection, usually bacterial, through the bloodstream and body.

*gangrene

(GANG-green) is the decay or death of living tissue caused by a lack of oxygen supply to the tissue and/or bacterial infection of the tissue.

*lymphangitis

(lim-fan-JIE-tis) is inflammation of the lymphatic system, the system that carries lymph through the body. Lymph is a clear fluid that contains white blood cells.

Necrotizing fasciitis

Necrotizing fasciitis (NEH-kro-tie-zing fashe-EYE-tis), also called flesh-eating disease, is a rare but potentially fatal disease caused by group A streptococcus bacteria infection. It affects the deeper layers of skin and tissues beneath the skin. Necrotizing fasciitis starts with sudden painful swelling and discoloration (red, purple, or bronze) of the skin. Often, the appearance of the affected skin does not reflect how far the infection has spread into the deeper layers of tissue. The disease can spread rapidly, with the infected area growing larger and darker. The ability to feel in the infected area disappears as the skin tissue dies. As the infection quickly progresses, the patient can become very ill. Early treatment with antibiotics and surgery to remove the damaged tissue is extremely important. Recovery may take several months.

Molluscum contagiosum

Molluscum contagiosum (moh-LUS-kum kon-tay-jee-O-sum), caused by a virus, produces small, solid, dome-shaped bumps on the surface of the skin. They are flesh-colored and pearly with a dimple in the center. The growths are similar to warts. Viruses cause both conditions—poxvirus in the case of molluscum contagiosum and human papillomavirus in the case of warts. Growths can be single, but they most often appear in groups on the trunk, arms, legs, and genitals* and occasionally on the face.

*genitals

(JEH-nih-tuls) are the external sexual organs.

The disease usually clears up by itself over several months, although new growths may arise on the skin if the virus spreads through contact with infected areas. Doctors may recommend home treatment with over-the-counter medications or removal of the growths by freezing, surgery, laser therapy, or acid treatments.

Herpes Simplex Virus

There are two types of the herpes simplex virus (HSV): HSV-1 and HSV-2. Both can show up as skin infections. HSV-1 can cause small, clear blisters (also known as cold sores, fever blisters, or oral herpes) on the face, and HSV-2 can cause blisters in the genital area. These blisters can break, bleed, and crust over, leaving red spots of healing skin.

There is no cure for either HSV-1 or HSV-2. Currently, antiviral medications can help control outbreaks of herpes virus and are used to treat genital herpes or sometimes recurrent cold sores from HSV-1.

Warts

Warts are caused by human papillomavirus (pah-pih-LO-mahvy-rus), or HPV. They can be skin-colored, pink, tan, or white, and they may appear anywhere on the body. Common warts usually are seen on the hands (especially around the nails), feet, and face, because the virus spreads most easily to those areas. Common warts are rough and raised, but plantar warts, found on the soles of the feet, are flat. Unlike other warts, plantar warts can be painful.

Many warts disappear by themselves after months or even years. Treatments are available for those that do not, including over-the-counter medications or professional treatment by freezing, surgery, laser therapy, or acid treatments.

Are Skin and Soft Tissue Infections Contagious?

Necrotizing fasciitis, cellulitis, and abscesses are not contagious from person to person, but the bacteria that can cause these infections can spread between people. Dermatophytes, warts, and molluscum contagiosum spread fairly easily through skin-to-skin contact.

How Are Skin and Soft Tissue Infections Diagnosed?

A doctor examines the size, shape, and color of the affected area and checks it for tenderness and warmth. The doctor may order blood tests for cellulitis to assess the extent of the infection; tests of skin scrapings for suspected fungal infections or molluscum contagiosum; or tests on a tissue sample for necrotizing fasciitis. Doctors can use a special type of filtered ultraviolet light to check for tinea capitis because the fungi that cause it glow a characteristic color when the light is shined on the infected area.

Can Skin and Soft Tissue Infections Be Prevented?

The best way to prevent skin and soft tissue infections is to avoid getting cuts, scrapes, bites, or any kind of open wound. Frequent hand washing can curb the spread of bacteria. Doctors also advise keeping any opening in the skin clean and dry. It is wise to consult a doctor if the area around the wound becomes reddened, hot, or painful or if the infected person develops a fever. Dermatophyte infection is best avoided by keeping the skin dry, such as in areas where sweating occurs.

See also

Abscesses

Fungal Infections

Gangrene

Herpes Simplex Virus Infections

Ringworm

Sepsis

Skin Parasites

Staphylococcal Infections

Warts

Resources

Organization

American Academy of Dermatology, P.O. Box 4014, Schaumburg, IL 60168. The American Academy of Dermatology offers fact sheets and general information about various skin problems on its website. Information for young people can be found through the Kids’ Connection at the website.

Telephone 847-330-0230 http://www.aad.org

Website

KidsHealth.org. KidsHealth is a website created by the medical experts of the Nemours Foundation and is devoted to issues of children’s health. It contains articles on a variety of health topics, including cellulitis, impetigo, tinea, warts, and other bacterial, fungal, and viral infections.

http://www.KidsHealth.org

Skin Lesions

Definition

A skin lesion is a superficial growth or patch of the skin that does not resemble the area surrounding it.

Description

Skin lesions can be grouped into two categories: primary and secondary. Primary skin lesions are variations in color or texture that may be present at birth, such as moles or birthmarks, or that may be acquired during a person's lifetime, such as those associated with infectious diseases (e.g. warts, acne, or psoriasis ), allergic reactions (e.g. hives or contact dermatitis ), or environmental agents (e.g. sunburn, pressure, or temperature extremes). Secondary skin lesions are those changes in the skin that result from primary skin lesions, either as a natural progression or as a result of a person manipulating (e.g. scratching or picking at) a primary lesion.

The major types of primary lesions are:

• Macule. A small, circular, flat spot less than 2/5 in (1 cm) in diameter. The color of a macule is not the same as that of nearby skin. Macules come in a variety of shapes and are usually brown, white, or red. Examples of macules include freckles and flat moles. A macule more than 2/5 in (1 cm) in diameter is called a patch.
• Vesicle. A raised lesion less than 1/5 in (5 mm) across and filled with a clear fluid. Vesicles that are more than 1/5 in (5 mm) across are called bullae or blisters. These lesions may may be the result of sunburns, insect bites, chemical irritation, or certain viral infections, such as herpes.
• Pustule. A raised lesion filled with pus. A pustule is usually the result of an infection, such as acne, imptigeo, or boils.
• Papule. A solid, raised lesion less than 2/5 in (1 cm) across. A patch of closely grouped papules more than 2/5 in (1 cm) across is called a plaque. Papules and plaques can be rough in texture and red, pink, or brown in color. Papules are associated with such conditions as warts, syphilis, psoriasis, seborrheic and actinic keratoses, lichen planus, and skin cancer.
• Nodule. A solid lesion that has distinct edges and that is usually more deeply rooted than a papule. Doctors often describe a nodule as "palpable," meaning that, when examined by touch, it can be felt as a hard mass distinct from the tissue surrounding it. A nodule more than 2 cm in diameter is called a tumor. Nodules are associated with, among other conditions, keratinous cysts, lipomas, fibromas, and some types of lymphomas.
• Wheal. A skin elevation caused by swelling that can be itchy and usually disappears soon after erupting. Wheals are generally associated with an allergic reaction, such as to a drug or an insect bite.

• Telangiectasia. Small, dilated blood vessels that appear close to the surface of the skin. Telangiectasia is often a symptom of such diseases as rosacea or scleroderma.

The major types of secondary skin lesions are:

• Ulcer. Lesion that involves loss of the upper portion of the skin (epidermis) and part of the lower portion (dermis). Ulcers can result from acute conditions such as bacterial infection or trauma, or from more chronic conditions, such as scleroderma or disorders involving peripheral veins and arteries. An ulcer that appears as a deep crack that extends to the dermis is called a fissure.
• Scale. A dry, horny build-up of dead skin cells that often flakes off the surface of the skin. Diseases that promote scale include fungal infections, psoriasis, and seborrheic dermatitis.
• Crust. A dried collection of blood, serum, or pus. Also called a scab, a crust is often part of the normal healing process of many infectious lesions.
• Erosion. Lesion that involves loss of the epidermis.
• Excoriation. A hollow, crusted area caused by scratching or picking at a primary lesion.
• Scar. Discolored, fibrous tissue that permanently replaces normal skin after destruction of the dermis. A very thick and raised scar is called a keloid.
• Lichenification. Rough, thick epidermis with exaggerated skin lines. This is often a characteristic of scratch dermatitis and atopic dermatitis.
• Atrophy. An area of skin that has become very thin and wrinkled. Normally seen in older individuals and people who are using very strong topical corticosteroid medication.

Causes and symptoms

Skin lesions can be caused by a wide variety of conditions and diseases. A tendency toward developing moles, freckles, or birthmarks may be inherited. Infection of the skin itself by bacteria, viruses, fungi, or parasites is the most common cause of skin lesions. Acne, athlete's foot (tinea pedis), warts, and scabies are examples of skin infections that cause lesions. Allergic reactions and sensitivity to outside environmental factors can also lead to the formation of skin lesions. Underlying conditions can also precipitate the appearance of skin lesions. For example, the decreased sensitivity and poor circulation that accompanies diabetes mellitus can contribute to the formation of extensive ulcers on extremities such as the feet. Infections of body's entire system can cause the sudden onset of skin lesions. For example, skin lesions are a hallmark symptom of such diseases as chicken pox, herpes, and small pox. Cancers affecting the skin, including basal cell carcinoma, squamous cell carcinoma, malignant melanoma, and Kaposi's sarcoma, are recognized by their lesions.

Diagnosis

Diagnosis of the underlying cause of skin lesions is usually based on patient history, characteristics of the lesion, and where and how it appears on the patient's body (e.g. pustules confined to the face, neck and upper back can indicate acne, while scales appearing on the scalp and face may indicate seborrheic dermatitis). To determine the cause of an infection, doctors may also take scrapings or swab samples from lesions for examination under a microscope or for use in bacterial, fungal, or viral cultures. In cases where a fungal infection is suspected, a doctor may examine a patient's skin under ultraviolet light using a filter device called a Woods light-under these conditions, certain species will taken on specific fluorescent colors. Dermatologists may also use contrast lighting and subdued lighting to detect variations in the skin. When involvement of the immune system is suspected, doctors may order a immunofluorescence test, which detects antibodies to specific antigens using a fluorescent chemical. In cases of contact dermatitis, a condition in which a allergic reaction to something irritates the skin, doctors may use patch tests, in which samples of specific antigens are introduced into the skin via a scratch or a needle prick, to determine what substances are provoking the reaction.

The vast majority of skin lesions are noncancerous. However, doctors will determine whether or not a particular lesion or lesions are cancerous based on observation and the results of an excisional or punch biopsy, in which a tissue sample is excised for microscopic analysis. Since early detection is a key to successful treatment, individuals should examine their skin on a monthly basis for changes to existing moles, the presence of new moles, or a change in a certain area of skin. When examining moles, factors to look for include:

• Asymmetry. A normal mole is round, whereas a suspicious mole is uneven.
• Border. A normal mole has a clear-cut border with the surrounding skin, whereas the edges of a suspect mole may be irregular.
• Color. Normal moles are uniformly tan or brown, but cancerous moles may appear as mixtures of red, white, blue, brown, purple, or black.

• Diameter. Normal moles are usually less than 1/5 in (5 mm) in diameter, a skin lesion greater than this may be suspected as cancerous.

Treatment

Treatment of skin lesions depends upon the underlying cause, what type of lesions they are, and the patient's overall health. If the cause of the lesions is an allergic reaction, removing the allergen from the patient's environment is the most effective treatment. Topical preparations can also be used to clean and protect irritated skin as well as to remove dead skin cells and scales. These may come in a variety of forms, including ointments, creams, lotions, and solutions. Topical antibiotics, fungicides, pediculicides (agents that kill lice), and scabicides (agents that kill the scabies parasite) can be applied to treat appropriate skin infections. Oral medications may be taken to address systemic infections or conditions. Deeply infected lesions may require minor surgery to lance and drain pus. Topical agents to sooth irritated skin and reduce inflammation may also be applied. Corticosteroids are particularly effective in reducing inflammation and itching (puritis). Oatmeal baths, baking soda mixtures, and calamine lotion are also recommended for the relief of these symptoms. A type of corticosteroid may be used to reduce the appearance of keloid scars. Absorbent powders may also be used to reduce moisture and prevent the spread of infection. In cases of ulcers that are slow to heal, pressure dressings may be used. At times, surgical removal of a lesion may be recommended-this is the usual course of therapy for skin cancer. Surgical removal usually involves a simple excision under local anesthetic, but it may also be accomplished through freezing (cryotherapy ) or laser surgery.

Prognosis

Skin lesions such as moles, freckles, and birthmarks are a normal part of skin and will not disappear unless deliberately removed by a surgical procedure. Lesions due to an allergic reaction often subside soon after the offending agent is removed. Healing of lesions due to infections or disorders depends upon the type of infection or disorder and the overall health of the individual. Prognosis for skin cancer primarily depends upon whether or not the lesion is localized and whether or not it has spread to other areas of the body, such as the lymph nodes. In cases where the lesion is localized and has not spread to other parts of the body, the cure rate is 95-100%.

Prevention

Not all skin lesions are preventable; moles and freckles, for example, are benign growths that are common and unavoidable. However others can be avoided or minimized by taking certain precautions. Skin lesions caused by an allergic reaction can be avoided by determining what the offending agent is and removing it from the home or workplace, or, if this is impossible, developing strategies for safely handling it, such as with gloves and protective clothing. Keeping the skin, nails, and scalp clean and moisturized can help reduce or prevent the incidence of infectious skin diseases, as can not sharing personal care items such as combs and make-up with others. Skin lesions associated with sexually transmitted diseases can be prevented by the use of condoms. Scratching or picking at existing lesions should be avoided since this usually serves only to spread infection and may result in scarring. Individuals who have systemic conditions, such as diabetes mellitus or poor circulation, that could lead to serious skin lesions should inspect their bodies regularly for changes in their skin's condition. Regular visual inspection of the skin is also a key to preventing or minimizing the occurrence of skin cancer, as is the regular use of sun screens with an SPF of 15 or more.

Resources

BOOKS

Rosen, Theodore, Marilyn B. Lanning, and Marcia J. Hill. The Nurse's Atlas of Dermatology. Boston: Little Brown & Co., 1983.

KEY TERMS

Corticosteroid— A type of steroid medication that helps relieve itching (puritis) and reduce inflammation.

Fibroma— A usually benign tumor consisting of fiborous tissue.

Lesion— A possibly abnormal change or difference in a tissue or structure, such as the skin.

Lipoma— A usually benign tumor of fatty tissue.

Patch test— Test in which different antigens (substances that cause an allergic reaction) are introduced into a patient's skin via a needle prick or scratch and then observed for evidence of an allergic reaction to one or more of them. Also known as a scratch test.

Woods light— Device that allows only ultraviolet light to pass through it.

SKIN DISORDERS

DEFINITION

Skin disorders include a variety of medical problems associated with the skin. Three common forms of skin disorder are dermatitis, psoriasis (pronounced suh-RY-uh-siss), and vitiligo (pronounced vit-ihl-EYE-go).

DESCRIPTION

Dermatitis

Dermatitis is a general term used to describe inflammation of the skin. Most types of dermatitis are characterized by a pink or red rash that itches. The most common form of dermatitis is contact dermatitis. This condition is caused by an allergic reaction to some material. It can occur on any part of the body, but appears most often on the hands, feet, and groin.

Contact dermatitis usually does not spread from one person to another. In some cases, however, it can be transferred from one part of the body to another. Poison ivy is an example. A person infected with poison ivy may first start scratching on the hands. But the infection may then be transferred to other parts of the body.

Other forms of dermatitis are less common. They include:

• Statis dermatitis, which is characterized by scaly, greasy-looking skin. This form most commonly affects the lower legs and ankles.
• Nummular dermatitis, which affects the hands, arms, legs, and buttocks. The condition occurs most commonly in men and women over the age of fifty-five.
• Atopic dermatitis, which usually occurs in early childhood. It is sometimes called infantile eczema. It usually occurs on the face, inside the elbows, and behind the knees.
• Seborrheic dermatitis (pronounced SEB-uh-REE-ick dur-muh-TY-tuhss), which may be dry or moist. It causes the formation of greasy scales and yellow crusts. The body parts most affected are the scalp, eyelids, face, ears, underarms, breasts, and groin.

Psoriasis

Psoriasis is a chronic (long-lasting), non-contagious disease characterized by open sores in the skin that become covered with silvery-white scabs.

Psoriasis affects about four million Americans. The disease may develop at any age. About 10 to 15 percent of all cases are first diagnosed during childhood. The average age of diagnosis is twenty-eight.

Psoriasis occurs when skin cells start to grow very rapidly. Normally, the rates at which skin cells grow and die off are about the same. As old skin cells die, new ones replace them. In the case of psoriasis, new skin cells grow much more rapidly than old cells die off. As a result, new skin cells push older dead skin cells upwards. They form patches of dead skin on the arms, back, chest, elbows, legs, nails, and scalp. These patches are the scabs that are characteristic of psoriasis.

Vitiligo

Vitiligo is a condition in which smooth, white patches develop on the skin. It is caused when melanocytes die off. Melanocytes (pronounced MELL-uh-no-sites) are skin cells that give skin their color.

Vitiligo affects 1 to 2 percent of the world's population. It occurs equally among men and women. The disorder can first appear at any age. In about half of all cases, however, it starts before the age of twenty.

Vitiligo may appear as one or two well-defined white patches on the skin. Or it may cover large portions of the body. People with vitiligo often have other medical problems also, such as eye disorders, thyroid disease, diabetes mellitus, and pernicious anemia (see entries on visions disorders, diabetes mellitus, and anemias).

Skin Disorders: Words to Know

Allergic reaction:

A series of events initiated by the immune system against substances that are normally harmless to the body.

Chronic:

A condition that continues for a long period of time.

Immune system:

A network of organs, tissues, cells, and chemicals designed to fight off foreign invaders, such as bacteria and viruses.

Melanocyte:

A specialized skin cell that produces melanin, a dark pigment (color) found in skin.

Rash:

A spotted pink or red skin condition that may be accompanied by itching.

Steroids:

A category of naturally occurring chemicals that are very effective in reducing inflammation and swelling.

Ultraviolet (UV) light:

A naturally occurring part of ordinary sunlight that may, under some circumstances, have beneficial effects in curing certain medical disorders.

CAUSES

Dermatitis

Contact and atopic dermatitis are allergic reactions. Allergic reactions are caused by the body's immune system. The immune system is a network of organs, tissues, cells, and chemicals designed to fight off foreign invaders, such as bacteria and viruses. Sometimes the immune system reacts to substances that are normally harmless to the body. It attacks the harmless material in the same way it would attack a disease-causing organism. Such responses are allergic reactions.

Allergic reactions can be caused by a great variety of objects, including:

• Flowers
• Herbs
• Vegetables
• Chlorine
• Household cleansers
• Detergents and soaps
• Fabric softeners
• Glues
• Perfumes
• Certain types of medications

Statis dermatitis is caused by poor circulation in the legs. Fluids collect in the lower legs, and they begin to swell. The swelling may cause a red, itchy rash.

The cause of nummular dermatitis is not known. A number of factors that can increase the risk for the disorder include hot or cold weather, stress, allergies, and bathing more than once a day.

Seborrheic dermatitis is cased by an over-production of oil glands in the skin.

Psoriasis

The cause of psoriasis is not known. However, researchers have identified a number of factors related to the occurrence of the disorder. These factors include:

• History of psoriasis in a person's family
• Stress
• Exposure to cold temperatures
• Injury, illness, or infection
• Use of steroids or certain other medications

Vitiligo

The cause of vitiligo is not fully understood. There appears to be a strong genetic factor involved. That is, the disorder seems to occur commonly in certain families. The condition is usually triggered by some stressful event, such as an accident, job loss, death of a family member, severe sunburn, or serious illness.

SYMPTOMS

The symptoms of all forms of contact dermatitis and psoriasis are similar. They include a red, itchy rash that covers specific areas of the skin. In the case of vitiligo, the primary symptom is the loss of skin color. People with vitiligo may have other symptoms also, such as abnormal eye coloring.

DIAGNOSIS

All forms of skin disorders can be diagnosed fairly easily based on visual observation. The skin rashes associated with contact dermatitis and psoriasis are very distinctive. A doctor may scrape off a small sample of skin for examination under the microscope. That examination can usually provide positive identification of the specific condition bothering the patient.

TREATMENT

Contact Dermatitis

One step in treating the allergic reactions that cause contact dermatitis is to eliminate the substance that causes the reaction. For example, people who are allergic to certain household cleanser should not use those cleansers. They should find substitutes for them.

The itchiness and inflammation caused by dermatitis can be treated with a variety of products. The most effective products contain steroids. A doctor's advice should be sought, however, as some over-the-counter products can make a patient's condition worse. Antihistamines can also be taken to reduce an allergic reaction. These products act against the chemicals produced by the immune system that cause a rash.

Patients with other forms of dermatitis may require specialized treatments. For example, patients with statis dermatitis should elevate their legs whenever possible. They should sleep with a pillow under their lower legs.

Psoriasis

The treatment of psoriasis depends on the severity of a patient's condition. Mild cases may be treated in much the same way as contact dermatitis. Steroid creams often relieve the itchiness of rashes and scabs.

More serious cases of psoriasis may be treated with applications of ultraviolet light. Ultraviolet (UV) light is a naturally occurring part of ordinary sunlight. Under some circumstances, it can have beneficial effects in curing certain medical disorders. But it can also have serious side effects. It should be administered only under the direction of a medical professional. UV light may also be used in conjunction with steroids and other medications.

The most severe cases of psoriasis are difficult to treat. Various medications are available for use, but most have serious side effects. Methotrexate has become popular for the treatment of psoriasis, but it can damage the liver. A number of deaths have occurred among patients whose liver functions were not adequately checked by doctors.

Vitiligo

Vitiligo can not be cured, but it can be managed. The primary goal is to improve the appearance of the white areas caused by the condition. Careful use of cosmetics and selection of clothing can help. Patients may also need counseling about their condition. Extreme cases of vitiligo can be very unattractive. Patients may need help in learning how to live with their disorder.

Alternative Treatment

As with traditional medicine, the first step recommended for treating contact dermatitis is removal of the material that causes the allergy. Alternative practitioners then have a number of ways for relieving the redness and itchiness of a rash. These include:

• A warm oatmeal bath
• Clay or mud packs
• Herbal remedies, such as burdock root, calendula, chamomile, cleavers, evening primrose oil, nettles, and sassafras

Suggested treatments for psoriasis, in addition to the ones listed above, include:

• Soaking in a warm chamomile or salt water bath
• Drinking up to three cups a day of hot tea made from burdock root, dandelion root, Oregon grape, sarsaparilla, or balsam pear
• Eating a diet rich in fish, turkey, celery, parsley, lettuce, lemons, limes, fiber, and fruit and vegetables
• Drinking at least eight glasses of water a day
• Taking nutritional supplements, such as folic acid, lecithin, vitamin A, vitamin E, selenium, and zinc

PROGNOSIS

Contact dermatitis can be controlled in most cases if the agent that causes the reactions is avoided or eliminated. Future exposure to the agent is likely to cause a reoccurrence of the condition.

The symptoms of psoriasis can often be treated successfully. However, the disease can not be cured and may become worse over time. Patients with the most severe forms of the disorder may require counseling as well as medical advice. The condition can become very disfiguring and emotionally upsetting for the patient.

Vitiligo may become stable or slowly grow worse over time.

PREVENTION

Most cases of contact dermatitis can be prevented if the agent that causes the allergic response can be identified. If the agent can not be

avoided, other forms of prevention are possible. For example, a person who has to work with a chemical that causes a reaction should use gloves and protective clothing. People who accidentally come into contact with an agent that causes an allergy should wash thoroughly with soap and water as soon as possible.

Neither psoriasis nor vitiligo can be prevented. However, psoriasis has the potential to develop into more serious conditions. For that reason, patients should monitor the status of their condition. They should seek medical help if they develop a fever, begin to feel achy, feel unusually tired, or experience other unusual symptoms.

FOR MORE INFORMATION

Books

Editors of Time-Life Books. The Medical Advisor: the Complete Guide to Conventional and Alternative Treatments. Alexandria, VA: Time-Life, Inc., 1996.

Gottlieb, Bill, ed. New Choices in Natural Healing. Emmaus, PA: Rodale Press, 1995.

Organizations

American Academy of Dermatology. PO Box 681069, Schaumburg, IL 60618–4014. (703) 330–0230. http://www.aad.org.

American Skin Association. 150 E. 58th St., 3rd Floor, New York, NY 10155–0022. (212) 688–6547.

Frontier's Foundation for Vitiligo and Pigment Disorders. 4 Rozina Court, Owings Mills, MD 21117. (301) 594–0958.

National Foundation for Vitiligo and Pigment Disorders. 9032 South Normandy Dr., Centerville, OH 45459. (513) 885–5739.

National Psoriasis Foundation. 6600 SW 92nd Ave., Suite 300, Portland, OR 97223. (800) 723–9166. http://www.psoriasis.org.

National Vitiligo Foundation. PO Box 6337, Tyler, TX 75703. (903) 531–9767.

Web sites

"Ask NOAH About: Dermatology." NOAH: New York Online Access to Health. [Online] http://www.noah.cuny.edu/dermatology/derm.html#skininfections (accessed on October 31, 1999).

Skin Pigmentation Disorders

Definition

Skin pigmentation disorders are conditions that cause the skin to appear lighter or darker than normal, or blotchy and discolored.

Description

People of all races have skin pigmentation disorders. Some disorders, like albinism (which affects one out of every 17,000 people) are rare. Others, such as age spots, are very common.

Skin pigmentation disorders occur because the body produces either too much or too little melanin, a pigment that creates hair, skin, and eye color. Melanin protects the body by absorbing ultraviolet light.

In hypopigmentation means the body does not produces enough melanin. Albinism, for example, is an inherited condition that causes a lack of pigment. So people with albinism typically have light skin, white or pale yellow hair, and light blue or gray eyes. Another condition called vitilgo, creates smooth, depigmented white spots on the skin. Vitilgo affects nearly 2% of the population, but it strikes people between 10 and 30 years old more often, and is more evident in people with darker skin.

In hyperpigmentation, the body produces too much melanin, causing skin to become darker than usual. Lichen simplex chronicus is a skin disorder with severe itching that causes thick, dark patches of skin to develop. Lamellar ichthyosis (fish scale disease) is an inherited disease that also is characterized by darkened, scaly, dry patches of skin.

Hyperpigmentation also occurs in melasma, a dark mask-like discoloration that covers the cheeks and bridge of the nose. Melasma can occur during the end of pregnancy. People with the autoimmune disease (when immune cells, which attack invaders, become abnormally programed to kill self cells inside the body) systemic lupus also may develop a similar butterfly-shaped mask on their faces. In addition, many people have moles, freckles, age spots, and birthmarks, ranging from red or brown to bluish, black, covering various parts of their bodies.

Causes and symptoms

Scientists are still studying the reasons why skin pigmentation disorders occur. In some cases there are tangible causes, such as sun exposure, drug reactions or genetic inheritance. In other cases, it is not as clear.

Albinism is an inherited recessive trait. Albinism has many different forms, but most people who have this condition have pale skin, hair, and eyes. Melanin also creates eye color, and serves as a filter that prevents too much light from entering the eye. Since they lack melanin in their eyes, many people with albinism also have visual impairment. With little skin pigmentation, they also sunburn easily and are more prone to skin cancer.

The hypopigmentation spots associated with vitilgo sometimes form where a person has been cut or injured. Research has shown that the light patches associated with vitilgo do not contain melanocytes, the type of skin cells that create melanin. Some scientists believe vitilgo may be caused by an autoimmune disorder. It also has been linked to other conditions such as hyperthyroidism (too much thyroid hormone) and Addison's Disease, which affects the adrenal gland.

Hyperpigmentation can be caused by many factors, from too much sunbathing to drug reactions or poor nutrition. Wounds and scars also can develop darker patches of skin. A psychological syndrome gives people with lichen simplex chronicus to develop a compulsive need to scratch, which causes dark, leathery skin to form. This can lead to permanent scarring and infection if untreated. Scientists believe lamellar ichthyosis is caused by genetics.

The mask caused by melasma may be related to pregnancy hormones, and usually disappears after a woman gives birth. Birthmarks, moles, and aging spots usually are harmless. Some moles, however, can change in size, color, texture, or start bleeding, which could indicate possible skin cancer.

Diagnosis

Diagnostic tests vary for different types of skin pigmentation disorders. Physicians usually can diagnose albinism by looking carefully at a person's hair, skin, and eyes. They may order blood tests and eye exams as well. A visual exam also is enough to diagnose vitilgo.

For most hyperpigmentation disorders, doctors can make a diagnosis by looking at a person's appearance. To detect conditions like lichen simplex chronicus or lamellar ichthyosis, or skin cancer, they may also do a biopsy to remove some of the affected skin for further study under a microscope. Some physicians also use a wood's lamp, or black light test, to diagnose skin conditions. Affected areas would absorb the ultraviolet light and stand out with flourescent colors in the darkened room.

KEY TERMS

Melanin— A pigment that creates hair, skin and eye color. Melanin also protects the body by absorbing ultraviolet light.

Melanocytes— The type of skin cells that create melanin.

Albinism— An inherited condition that causes a lack of pigment. People with albinism typically have light skin, white or pale yellow hair and light blue or gray eyes

Hypopigmentation— A skin condition that occurs when the body has too little melanin, or pigment.

Hyperpigmentation— A skin condition that occurs when the body has too much melanin, or pigment.

Lichen simplex chronicus— A skin disorder with severe itching that causes thick, dark patches of skin to develop.

Vitilgo— A skin disorder that creates smooth, depigmented white spots on the skin.

Lamellar ichthyosis— Also called fish scale disease, this inherited condition is characterized by darkened, scaly, dry patches of skin.

Melasma— A dark mask-like discoloration that covers the cheeks and bridge of the nose. Also called "the mask of pregnancy."

Treatment

For albinism, healthcare providers advise people to cover up, use sunscreen and avoid excess sunlight to prevent skin cancer. People with albinism also must wear protective sunglasses and, in some cases, prescription corrective lenses. Surgery may be necessary to correct visual impairments.

To treat vitilgo, physicians may prescribe a combination of photo-sensitive medications like trimethylpsoralen and ultraviolet light therapy to darken the spots. If the person has depigmented patches covering more than 50% of the body, doctors also may be able to use skin bleaching agents like monobenzone to give the skin a lighter, more uniform appearance. Other options include cosmetic concealers and skin grafting.

Skin-lightening creams are available for hyper-pigmentation disorders. Doctors also advise staying out of the sun. Counseling with a dietitian may help in cases caused by poor nutrition. For lichen simplex chronicus, doctors could prescribe antihistamines and topical steroid creams to stop the itching. If a mole or birthmark appears suspicious, physicians often will surgically remove it to prevent skin cancer.

Prognosis

Most skin pigmentation disorders do not affect a person's health, only the outward appearance.

Prevention

In most cases, doctors will recommend using sunscreen and avoiding too much sun exposure.

Resources

PERIODICALS

Wilson, Tracy. "The Paler Side of Beauty." Heart and Soul 6, no. 1 (February 1999): 30-33.

ORGANIZATIONS

American Academy of Dermatology. 930 N. Meacham Road, P.O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. 〈http://www.aad.org〉.

National Organization for Albinism and Hypopigmentation (NOAH), 1530 Locust St., #29, Philadelphia, PA, 19102-4415. (800) 473-2310. 〈http://www.albinism.org〉.

OTHER

MelanomaNet. 〈http://www.skincarephysicians.com/melanomanet/index.html〉.

National Weather Service. "Ultraviolet Light Index." 〈http://www.nws.noaa.gov/pa/secnews/uv/index.html〉.