(LifeWire) - Rashes, bumps, redness and itching -- although these generic skin symptoms seem similar, they can signal the presence of a number of different conditions, such as rosacea, psoriasis and eczema. All three tend to be chronic and although rarely life threatening, they can lead to complications of varying severity if left untreated. Here's a primer to explain these oftentimes confounding skin conditions.
Rosacea occurs primarily on the face. It causes easy and severe blushing or flushing, hotness, redness, bumps and swelling. Tiny blood vessels, pimples, pustules crop up within the areas of redness, but no blackheads. Over time, the blood vessels become enlarged. While rosacea is generally harmless, it can be frustrating to have such a visible condition.
Rosacea is more common among those who are fair-skinned, and it strikes about three times as many women as men. This is believed to be due to hormonal issues, particularly those that occur around the time of menopause. But it can develop at any age, even during childhood.
Scientists are still trying to understand the underlying causes of rosacea, but triggers include temperature extremes or changes, sunburn, stress, menstruation, personal care products and cosmetics that contain alcohol, scrubbing of the face, hot beverages, spicy foods, caffeine, alcohol and certain medications.
Symptoms often come and go, with periods of time when the symptoms are more severe and periods of time when they are milder. Initially the very center areas of the face are affected, with the flushness spreading over time to the cheeks, forehead, chin and nose. The condition can even spread to include the eyes, ears, chest and back. Rosacea can be permanent.
Half of the people with rosacea develop a problem called ocular rosacea, in which the eyes sting, burn and feel gritty. Left untreated, eye infections can lead to problems with vision. Rhinophyma is a term that refers to enlargement of the oil glands in the face, causing swollen red cheeks and an enlarged red nose. Rhinophyma tends to strike men who have had rosacea for years. Although rhinophyma is not a sign of alcoholism, cartoon stereotypes have unfairly led people to believe this common misperception.
A variety of topical treatments may be helpful, including antibiotics, antifungal medicines, benzoyl peroxide and vitamin A creams (retinoids). Steroid creams should only be used for short bursts (no more than 2 weeks at a time) to decrease redness. Note that steroids can actually worsen rosacea if used incorrectly. Catapres (clonidine) can improve flushing/blushing. Laser treatment or electrodessication (use of a tiny needle that delivers electricity to the blood vessel, destroying it) may be used to close up blood vessels close to the surface of the skin. Rhinophyma may become disfiguring enough to require surgery. Also, beta-blockers are sometimes helpful to treat the flushing associated with rosacea.
The most common form of psoriasis is called plaque psoriasis, in which areas of the skin become covered by thick, red patches (the so-called plaques), topped by a silvery-white scale. It can occur anywhere on the skin, but usually affects the elbows, knees and scalp. These areas can be itchy and tender. The scalp often becomes very scaly, resembling dandruff. Nails may become pitted, ridged and loose. Other forms of psoriasis may appear slightly different as follows:
Guttate psoriasis: Small, tear-drop shaped, salmon pink spots that appear most often on the trunk, arms and legs, but may cover the entire body.
Pustular psoriasis: Inflamed, red skin covered with pus-filled bumps, often found on the palms of the hands and soles of the feet.
Inverse psoriasis: Smooth, red inflamed areas of skin within areas of skin folds, such as the armpits, under the breasts and in the groin area.
Erythrodermic psoriasis: A rare, potentially severe form of psoriasis causing widespread redness, swelling and itching all over the body. In extreme cases, complications like overwhelming infection, dehydration and congestive heart failure can cause this condition to become life threatening.
Psoriasis can develop at any age, even during childhood. It tends to run in families, and it waxes and wanes in severity over the course of a lifetime. What happens is that the immune system treats the skin like a foreign invader, attacking and damaging it. Infections are frequent triggers, especially strep infections, which are highly correlated with guttate psoriasis; so it's important to have a strep test, and if it's positive, a course of antibiotics should be started. Other possible triggers include skin injury, sunburn, severely dry skin, stress and taking medications, such as lithium or interferon.
Between 10% to 30% of people with psoriasis develop a form of arthritis that can range from uncomfortable to debilitating.
A variety of topical treatments may help improve symptoms of psoriasis, including steroid preparations, anthralin, Dovonex (calcipotriene), vitamin A creams and coal tar-containing preparations. Exposure to ultraviolet (UV) light may improve symptoms, whether it's natural, outdoor sunlight or a special lamp/light in a doctor's office. Severe psoriasis may require treatment with powerful immune suppressant medications, such as Trexall (methotrexate), Sandimmune (cyclosporine) and biologic drugs including Enbrel (etanercept), Remicade (infliximab) or Humira (adalimumab).
Eczema is believed to be an allergic reaction that evolves into a cycle of redness, itching and more redness and itching, as the scratching and rubbing only aggravate the skin further. Affected areas may become cracked, discolored, blistered, crusty or scaly, and may weep a clear fluid. People with eczema are at increased risk for developing skin infections, such as staph.
Eczema can crop up anywhere, although common areas are in skin folds, on cheeks and on the backs of the hands, tops of the arms and front of the legs.
This condition can develop at any age, even during infancy. It usually begins before age 5. About 40% of children "grow out" of their eczema. Others experience flare-ups throughout their lives. Eczema tends to run in families, especially those prone to allergies and asthma.
Triggers include temperature changes, dry skin, irritants -- such as wool, dyes, cosmetics, perfumes and soaps -- foods -- most especially eggs, peanuts, fish, soy, wheat and dairy -- and stress, dust mites, pollen and animal dander.
It's important to keep skin clean and well-moisturized. Topical steroids can improve redness and itching. Topical immunomodulators such as Elidel (pimecrolimus) and Protopic (tacrolimus) can improve itching and redness, but should only be used for short periods of time. Oral antihistamines can improve itching. In severe cases, oral steroids, Trexall (methotrexate), Sandimmune (cyclosporine) or Imuran (azathioprine) might be needed. Another important component of skin care is to take short, warm (not hot) showers and to use a non-soap cleanser. Also, apply moisturizer to the entire body within three minutes of getting out of the shower.
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"Psoriasis & Psoriatic Arthritis." AAD.org. 2008. American Association of Dermatology. 23 Jun. 2008 <http://www.aad.org/public/publications/pamphlets/skin_eczema.html>.
"Rosacea." AAD.org. 2008. American Association of Dermatology. 23 Jun. 2008 <http://www.aad.org/public/publications/pamphlets/common_rosacea.html>.