A skin lesion is an abnormal growth or patch of skin that doesn't look like the area nearby. Skin lesions can be divided into two categories: primary andsecondary.
Primary skin lesions are variations in color or texture that may be present at birth, such as moles or birthmarks. They also may appear during a person'slifetime, such as warts, acne, or psoriasis, allergic reactions such as hivesor sunburn.
Secondary skin lesions include changes in the skin caused by primary skin lesions, either as a natural progression or because of scratching or picking atthe skin.
The major types of primary lesions are:
- Macule. A small, circular, flat spot less than a quarter of an inch wide. The color of a macule is different from nearby skin, and are usually brown, white, or red. Freckles and flat moles are considered macules. Macules bigger than an inch are called patches.
- Vesicle. A raised lesion less than a a quarter of an inch across filled with clear fluid; vesicles bigger than this are called blisters. Vesiclesmay be caused by sunburn, insect bites, chemical irritation, or some viral infections, such as cold sores.
- Pustule. A raised lesion filled with pus usually caused by an infection, such as impetigo or boils.
- Papule.A solid, raised, rough lesion that may be red, pink or brown. A patch of closely-grouped papules is called a plaque. Papules are associated with conditions such as warts, syphilis, psoriasis, or skin cancer.
- Nodule. A solidlesion with distinct edges that is usually more deeply rooted than a papule.A nodule feels like a hard mass, distinct from the skin around it. A large nodule is called a tumor.
- Wheal. A raised skin lesion that can be itchy and usually disappears soon after it appears. Wheals are generally part ofan allergic reaction.
- Telangiectasia. Small, dilated blood vessels that appear close to the surface of the skin. Telangiectasia is often a symptomof skin diseases such as rosacea or scleroderma.
The major types of secondary skin lesions are:
- Ulcer. Lesion that erodes the upper portion of the skin and part of the lower portion beneath. Ulcers can be caused by conditions such as bacterial infection or injury, or frommore long-lasting problems such as scleroderma. An ulcer that looks like a deep crack in the skin is called a fissure.
- Scale. A dry build-up of dead skin cells that often flakes off the surface of the skin. Diseases that cause scale include fungal infections and psoriasis.
- Crust. A dried collection of blood, serum, or pus. Also called a scab, a crust is often part ofthe normal healing process of many infectious lesions.
- Excoriation.A hollow, crusted area caused by scratching or picking at a skin sore.
- Scar. Discolored, fibrous tissue that permanently replaces normal skin after the tissue has been destroyed. A very thick and raised scar is called a keloid.
- Atrophy. An area of skin that has become very thin and wrinkled.Normally seen in older people and those who use very strong corticosteroid skin creams.
Skin lesions can be caused by a wide variety of conditions and diseases, anda tendency for developing moles, freckles, or birthmarks may be inherited. Infection of the skin itself by germs or parasites is the most common cause ofskin lesions. Acne, athlete's foot, warts, and scabies are all examples of skin infections that cause lesions. Allergic reactions and sensitivity also cancause skin lesions. Underlying conditions can also trigger a skin lesion. For example, the decreased sensitivity and poor circulation that comes with diabetes can lead to the development of ulcers on the legs and feet. Infectionsof body's entire system can cause the sudden onset of skin lesions, such as witih chicken pox or herpes.
Diagnosis of the underlying cause of skin lesions is usually based on patienthistory, what the lesion looks like, and where it appears on the body. To determine the cause of an infection, doctors may also take scrapings or swab samples for various lab tests. In cases of suspected allergy, doctors may use skin tests to find out what substances are causing the reaction.
Doctors can determine if a skin lesion is cancerous by taking a sample of theskin and analyzing it under a microscope. Since early detection is a key tosuccessful treatment of cancer, patients should examine their skin on a monthly basis for skin changes or the presence of new growths. When examining moles, factors to look for include:
- Asymmetry. A normal mole is round, buta suspicious mole is uneven.
- Border. A normal mole has a clear-cut border but the edges of a suspect mole may be irregular.
- Color. Normalmoles are uniformly tan or brown, but cancerous moles may be mixtures of red, white, blue, brown, purple, or black.
- Diameter. Normal moles are usually less than 15 inches in diameter; anything bigger than that may be cancerous.
Treatment of skin lesions depends upon the cause, what type of lesions they are, and the patient's overall health. If the cause of the lesions is an allergic reaction, avoiding the allergy trigger is the most effective treatment. Skin preparations can 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, lice-killing and scabies-killing drugs can be applied to treat appropriate skin infections. Oral medications may be taken to treat body-wide infections or diseases. Deeply-infected lesions may require minor surgery to lanceand drain pus. Corticosteroids are particularly effective in reducing inflammation and itching (puritis). Oatmeal baths, baking soda mixtures, and calamine lotion are also recommended to ease symptoms.
Sometimes surgical removal of a lesion may be recommended, especially when treating skin cancer. Surgical removal usually involves simply cutting away thegrowth under local anesthetic, but growths may be removed by freezing (cryotherapy) or laser surgery.
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 mostly depends on whether or not the lesion has spread to other parts of the body.
Not all skin lesions are preventable; moles and freckles, for example, 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 staying away from the offending agent, or figuring out how to safely handling it. Keeping the skin, nails, and scalp clean and moisturized, and not sharing personal care items such as combs and make-up with others, can help reduce or prevent infectious skin diseases. Skin lesions associated with sexually transmitted diseases can be prevented by using condoms. Individuals who have conditions such as diabetes or poor circulation that could lead to seriousskin lesions should inspect their bodies regularly for changes in their skin. Staying out of the sun or using effective sunscreens can cut down on skin cancer.