A rash

A rash is a change of the skin which affects its color, appearance or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, dry, cracked or blistered, swell and may be painful. The causes, and therefore treatments for rashes, vary widely. Diagnosis must take into account such things as the appearance of the rash, other symptoms, what the patient may have been exposed to, occupation, and occurrence in family members. The diagnosis may confirm any number of conditions.

How do you get scabies?

Scabies mites are very sensitive to their environment. They can only live off of a host body for 24-36 hours under most conditions. Transmission of the mites involves close person-to-person contact of the skin-to-skin variety. It is hard, if not impossible, to catch scabies by shaking hands, hanging your coat next to someone who has it, or even sharing bedclothes that had mites in them the night before. Sexual physical contact, however, can transmit the disease. In fact, sexual contact is the most common form of transmission among sexually active young people. However, other forms of physical contact, such as mothers hugging their children, are sufficient to spread the mites. Over time, close friends and relatives can contract it this way, too. School settings typically do not provide the level of prolonged personal contact necessary for transmission of the mites.

What is scabies?

Scabies is an itchy skin condition caused by an infestation by the itch mite Sarcoptes scabiei. Mites are small eight-legged parasites (in contrast to insects, which have six legs). They are tiny, just 1/3 millimeter long, and burrow into the skin to produce intense itching, which tends to be worse at night. The mites that cause scabies are not visible with the naked eye but can be seen with a magnifying glass or microscope.

skin rashes

Whether it is used by patients or doctors, the word "rash" does not have an exact meaning or refer to a specific disease or kind of disorder. It's a general term that means an outbreak of bumps on the body that changes the way the skin looks and feels. Rashes can be localized to one area or else be widespread. The way people use this term, a rash can refer to many different skin conditions. Common categories of rash are

• scaly patches of skin not caused by infection
• scaly patches of skin produced by fungal or bacterial infection, and
• red, itchy bumps or patches all over the body
.

Although rashes are seldom dangerous, self-diagnosis is not usually a good idea. Proper evaluation of a skin rash requires a visit to a doctor or other healthcare professional. The following guidelines may help you decide what category your rash falls into.

Scaly patches of skin not caused by infection

Scaly, itchy skin patches often represent one of the conditions referred to as eczema.

Atopic dermatitis: Atopic dermatitis is perhaps the most common form of eczema. This is a hereditary skin problem that often begins in childhood as chapped cheeks and scaly patches on the scalp, arms, legs, and torso. Later in childhood, atopic dermatitis may affect the inner aspects of the elbows and knees. Adults get atopic dermatitis on the hands, around the eyelids, on the genitals, as well as on the body as a whole.

The word "dermatitis" means inflammation of the skin. "Atopic" refers to diseases that may be associated with allergies and tend to run in families. Atopic diseases include asthma, hay fever, and atopic dermatitis. In fact, people may refer to what doctors call eczema as "allergic skin." However, this is usually not the case. Patients with atopic dermatitis may have allergies, but most cases of atopic dermatitis are not themselves allergic.

Eczema comes and goes on its own schedule, in a manner not related to the allergy usual suspects—foods, soaps, and detergents—which may be blamed for flare-ups. In most cases, changing diet and detergents helps eczema very little.

Atopic dermatitis is often worse in the winter months, when the air is cold and dry, so that frequent washing may irritate the skin and aggravate the condition Although the skin feels "dry," it really isn't; it is inflamed, and therefore moisturizing alone does not help much.

Skin affected by atopic dermatitis becomes extremely itchy and inflamed. It may look red, swollen, and cracked. In some cases, the skin can also weep and crust. Liquid that oozes out of such crusts is often not infected; what comes out is the body's normal tissue fluid. Treatment specific for eczema is helpful, not antibiotics.

Patches of atopic dermatitis may appear on various parts of the body, but the condition is not contagious. It may appear off and on throughout life, but there may be long intervals between outbreaks. Also, the condition does not get progressively worse with age; if anything, it is most extensive during childhood.

Treatment of eczema involves minimizing irritation if that is contributing to the problem and using prescription-strength steroids (cortisone creams). Nonsteroidal creams like tacrolimus (Protopic) and pimecrolimus (Elidel) have become less popular both because of relative lack of effectiveness and concerns about safety. Tap water soaks with Burow's solution (available without prescription) can help dry up atopic dermatitis in its oozy stages.

Contact dermatitis: Contact dermatitis is a rash that is brought on either by contact with a specific material that causes allergy on the skin or with something that irritates the skin, like too-frequent hand washing.

Common examples of contact dermatitis caused by allergy are poison ivy and reactions to costume jewelry containing nickel. With occasional exceptions, allergic contact dermatitis affects just those parts of the skin touched by whatever material causes the allergy, as opposed to atopic dermatitis, which can be widespread because, as explained above, it is not an allergy to a specific substance.

Skin Problems

Healthy skin provides a barrier between the inside of the body and the outside environment. A rash means some change has affected the skin.

Rashes are generally caused by skin irritation, which can have many causes. A rash is generally a minor problem that may go away with home treatment. In some cases a rash does not go away or the skin may become so irritated that medical care is needed.

In adults and older children, rashes are often caused by contact with a substance that irritates the skin (contact dermatitis). The rash usually starts within 48 hours after contact with the irritating substance. Contact dermatitis may cause mild redness of the skin or a rash of small red bumps. A more severe reaction may cause swelling, redness, and larger blisters. The location of the rash may give you a clue about the cause.

Contact dermatitis does not always occur the first time you are in contact to the irritating substance (allergen). After you have had a reaction to the substance, a rash can occur in response to even very small amounts of the substance. Contact dermatitis is not serious, but it is often very itchy. Common causes of contact dermatitis include:

• Poisonous plants, such as poison ivy, oak, or sumac.
• Soaps, detergents, shampoos, perfumes, cosmetics, or lotions.
• Jewelry or fabrics.
• New tools, toys, appliances, or other objects.
• Latex. Allergy to natural rubber latex affects people who are exposed to rubber products on a regular basis, especially health care workers, rubber industry workers, and people who have had multiple surgeries. Latex allergies can cause a severe reaction.

Rashes may occur with viral infections, such as herpes zoster; fungal infections, such as a yeast infection (Candida albicans); bacterial infections, such as impetigo; and sexually transmitted diseases (STDs). Rashes may also occur as a symptom of a more serious disease, such as liver disease, kidney disease, or some types of cancer.

Rashes may also appear after exposure to an insect or a parasite, such as the scabies mite. You may develop a rash when you travel to a rural area or go hiking or camping in the woods.

A rash may be a sign of a chronic skin problem, such as acne, eczema, psoriasis, or seborrheic dermatitis. Other causes of rash include dry, cold weather; extremely hot weather (heat rash); and emotional stress. Emotions such as frustration or embarrassment may lead to an itchy rash.

The need for medical treatment often depends on what other symptoms are present. A rash that occurs with other symptoms, such as shortness of breath or fever, may mean another problem, such as a serious allergic reaction or infection.

A very rare and serious type of generalized red rash is toxic epidermal necrolysis (TEN). This rash may cause the skin to peel away, leaving large areas of tissue that weep or ooze fluid like a severe burn. If this type of rash occurs, you need to see a doctor. TEN may occur after the use of some medicines.

Review the Emergencies and Check Your Symptoms sections to determine if and when you need to see a doctor.