A skin lesion is a condition in which an area of the skin has a change in appearance. It may affect any area of skin, from one small spot to the entire body.
There are many types of changes that can take place in the skin. These include swelling, warmth, blisters, bumps, color changes, itching, and even pain. When several skin lesions occur at the same time, the condition is often called a rash. Causes for skin lesions can range from allergic reactions to infections and even cancer.
When a person complains of a lesion on the skin, the healthcare professional needs to know: how long the lesion has been presentwhere the lesion is locatedwhether there is one or more than one lesionthe description of the lesionhow the lesion started and whether it has changed over timewhether the lesion itcheswhether the person has experienced fever or chillswhether anyone the person knows has had similar skin changeswhether the person has any allergieswhat medical conditions the person may havewhat medications a person may be takingwhether the person has had similar or other skin lesions in the pastwhether the person has had any injury to the area or a recent insect or tick bite
The professional may ask about other symptoms as well, depending on the history and the results of the physical examination. These questions may concern arthritis, weight loss, or the person's sexual history.
There are many possible causes of a skin lesion. General categories include: injuries, including those resulting in bruises, cuts, punctures, scabs, and other damage to the skininsect bites, including those from mosquitoes, ticks, spiders, gnats, flies, ants, bees, and othersinfections, such as ringworm, Lyme disease, syphilis, measles, chickenpox, scabies, infectious mononucleosis, HIV, genital herpes, and herpes zoster allergic reactions. These can be from drugs or medications, metals, chemicals, soaps, foods, or other materials.primary skin diseases, such as acne, psoriasis, eczema, or rosacea. These often occur for unknown reasons.autoimmune disorders. These are conditions that occur a person's immune system attacks his or her own body for unknown reasons. Examples of autoimmune disorders include systemic lupus erythematosus and rheumatoid arthritis. Both of these conditions can affect many areas of the body.pregnancy other systemic conditions, such as diabetes skin cancer, such as a melanoma or basal cell carcinoma inflammation of blood vessels, called vasculitis, in the skin. An example of this condition is Henoch-Schonlein purpura, a condition that usually occurs in children after an infection.poor circulation, which commonly causes skin lesions in the lower legs known as stasis dermatitis. The poor circulation can be caused by damaged veins or diabetes.
Other causes are also possible. Sometimes, the cause cannot be found.
Prevention depends on the cause. It is often difficult to prevent skin lesions. Someone with allergies should avoid contact with the substance that causes the skin break out, whenever possible. Routine childhood vaccines can prevent some infections, such as measles and chickenpox, which cause skin lesions. Skin cancer protection includes avoiding unnecessary exposure to the sun. People with fair skin are particularly warned to avoid skin cancer risks..
The cause of some skin lesions can be diagnosed after a history and examination of the rash. Other lesions may be more difficult to identify, so further tests may be needed. The tests that are ordered depend on the suspected cause of the problem. For example, a blood test called an antibody titer can help diagnose some infections and autoimmune conditions.
A blood glucose level test can help diagnose diabetes. Blood tests such as a serum pregnancy test can help diagnose pregnancy. Sometimes, a biopsy of the affected skin is needed. In this procedure, a small piece of skin is removed with a special tool. The skin can then be analyzed in the lab to identify the cause of the lesion. Other tests may sometimes be needed, as well. For example, the professional may order a chest x-ray if he or she suspects a lung infection is causing the rash.
Some skin lesions, such as severe acne, may cause permanent scarring of the skin. Other lesions may become infected because of skin breakdown. In very rare cases, skin lesions can result in death. This can occur in the case of a severe allergic skin reaction.
For most skin lesions, the long-term effects are related to the underlying cause. For example, cancer or serious infections that cause skin lesions may result in death. Skin lesions associated with pregnancy often go away after delivery.
In some cases, skin lesions can be due to a contagious infection and may be spread to others. In most cases, however, skin lesions pose no risk to others.
Affected skin should be kept clean, especially if the skin is broken. Specific treatment depends on the cause. For example, a person with an infection may need oral antibiotics or antibiotic cream applied to the skin. An individual with an allergic reaction may need antihistamines or corticosteroid medications. Someone with an autoimmune disorder may need medications to suppress the immune system. Cancer or poor circulation may require surgery.
Side effects depend on the treatments used. For example, antihistamines often cause drowsiness. Other specific side effects depend on the medications used. Surgery can be complicated by bleeding, infection, or reactions to anesthesia.
If the lesion goes away, a person may or may not need further treatment. For example, someone with diabetes or poor circulation needs further treatment and monitoring even after the skin lesion heals. An individual with ringworm, a fungal infection of the skin, usually needs no further treatment once the condition goes away.
A person with skin breakdown needs to watch for infection until the skin heals over. Any new or worsening symptoms should be reported to the healthcare professional.
Cecil's Textbook of Medicine, 1996, Bennett et al.
Harrison's Principles of Internal Medicine, 1998, Fauci et al.