Eczema Information

Reviewed By: Kimberly Bazar, M.D., AAD

About eczema Eczema is an inflammation of the skin. It is not life-threatening or contagious. However, it typically causes itchiness, discomfort and a dry, scaly rash. The terms “eczema” and “dermatitis” are usually used interchangeably. There are several types of eczema, but most people use the term to refer to the most common variety known as atopic dermatitis. Eczema is a common condition that affects people of all ages and races. It usually begins early in life, typically before the age of 5, and often appears periodically throughout a person’s lifetime. In some cases, the condition will improve over time. In other cases, it will remain chronic (ongoing). Although some children outgrow the condition, they usually are plagued with dry skin that is easily irritated for the rest of their lives. Because the disease is intensely itchy, patients often have the urge to rub or scratch the affected area. However, this only makes the condition worse. Several different triggers for eczema have been identified. They include: Bacteria Abrasive clothing (e.g., wool) Consuming and handling certain foods Illness Jewelry Physical or mental stress Rubbing the skin Soaps, detergents, lotions Perfume Sweating Weather (hot, cold, humid or dry) Exposure to skin irritants (e.g., solvents such as gasoline) or allergens (e.g., dust mites, pollen, mold, pet dander) Eczema is often hereditary and may be found in other family members. People who suffer from severe eczema often also have hay fever or asthma, or have family members who do. Types and differences of eczema There are several different types of eczema. They include: Atopic dermatitis. The most common form of eczema. It may occur in association with allergies and frequently runs in families with a history of asthma or hay fever. It typically begins in infancy (where it is often related to food allergies) and varies in severity during childhood and adolescence before becoming less troublesome in adulthood. However, exposure to certain allergens or irritants can trigger an outbreak later in life. Stress can exacerbate atopic dermatitis. Some people use the term “atopic dermatitis” interchangeably with “eczema.” Contact dermatitis. Results from direct skin contact with various irritants (irritant contact dermatitis) or allergens (allergic contact dermatitis). Irritants include laundry soap, skin soaps and cleaning products. Allergens include rubber, metals such as nickel, jewelry, perfume, cosmetics, hair dye, weeds such as poison ivy, and neomycin, an ingredient often found in topical antibiotic creams. A brief exposure to a small amount of allergen can cause contact dermatitis. However, it takes a more significant amount of an irritant – and a longer period of exposure – to trigger irritant contact dermatitis. Neurodermatitis. Occurs when a tight garment or insect bite irritates the skin, leading to chronic scratching or rubbing and a subsequent rash that is dull red to brown, thickened and slightly scaly. Common locations include ankles, wrists, outer forearms or arms, and the back of the neck. Seborrheic dermatitis. Common in people with oily skin or hair, it involves an overproduction of skin cells and the skin’s natural oil (sebum). It may reoccur depending on the season of the year or whether the patient is under stress. People who have neurologic conditions such as Parkinson's disease or who are immunocompromised such as in HIV patients also are at risk for this form of eczema. Seborrheic dermatitis is often an inherited condition. Stasis dermatitis. Occurs on the lower legs when fluid builds up in tissues just beneath the skin, thinning out the skin and interfering with the blood's ability to nourish the skin. Stasis dermatitis is associated with varicose veins and other chronic conditions in the legs. Perioral dermatitis. Often associated with conditions such as rosacea, adult acne or seborrheic dermatitis of the skin around the mouth or nose. The precise cause is unknown, but exposure to makeup, moisturizers and dental products may be involved. Latex dermatitis. Occurs when the skin comes into contact with latex, a fluid produced by rubber trees and found in gloves, balloons, condoms and other products. Dyshidrotic dermatitis. An intensely itchy, chronic form of eczema that typically appears on the palms, fingers and soles of the feet. The cause of dyshidrotic dermatitis is unknown but may include allergies, exposure to irritants and stress. It often progresses to small, fluid-filled bumps, which peel off after one or two weeks. This leaves cracks in the skin that resolve slowly over time. Signs and symptoms of eczema The signs and symptoms of eczema vary from person to person and may range from mild to severe. In most cases, eczema begins as intense itching, followed by a patchy rash that is red, inflamed, dry and scaly. The rash most often appears on the face, arms and legs, and particularly affects the creases of the hands and feet. The rash often itches or burns and may ooze or become crusty when scratched. Rashes in children under age 2 tend to begin on the cheeks, elbows and knees. In adults, rashes are more likely to begin on the inside surfaces of knees and elbows. Adults are more likely than children to have patches that appear brownish, scaly and thickened. Some people with eczema develop red or clear fluid-filled bumps that look bubbly. Painful cracking also may occur. In some cases, eczema may cause other associated conditions. These may include: Infection. Affects the body through open sores and cracks associated with eczema. Infections associated with eczema include: Impetigo. A form of infection caused by staphylococci bacteria. It is often associated with atopic dermatitis. Cellulitis. Bacterial infection of tissues beneath the skin. Cellulitis manifests as red streaks of skin that are swollen, tender and warm to the touch. It often spreads and has indistinct margins. Cellulitis occurs when a patient’s immune system has been compromised, making it a potentially life-threatening condition that demands prompt medical attention. Lichen simplex chronicus. A toughening of the skin that manifests as small skin patches that become thickened and leathery with a dull red to brown color. It is caused by repeated scratching of the skin. Patients should consult a physician if they experience any of the following in relation to their eczema: Discomfort that causes the patient to lose sleep or become distracted from daily routines Extremely painful skin Indications that the skin may be infected Presence of a fever Failure to see improvement in eczema despite self-care measures Diagnosis methods for eczema To diagnose eczema, a physician will perform a complete physical examination and compile a thorough medical history. Other tests may also be performed. For example, a physician may conduct patch testing that exposes a patient’s skin to various substances to determine if any of the substances inflame the skin, which would be characteristic of contact dermatitis. Allergy testing may occasionally be necessary to identify allergens that may trigger atopic dermatitis. A physician may also take a scraping of the rash and examine it under a microscope to make sure it is not caused by a fungus. Eczema is usually diagnosed if three conditions are present: Characteristic scaly rash Intense itching Personal or family history of asthma, hay fever or other allergies Treatment options for eczema Treatment options for eczema may depend on the type of eczema being treated, and whether it manifests as dry and scaly lesions, dry and thickened lesions or weeping lesions. In general, the goal is to reduce skin inflammation, dryness and itchiness. Medications such as over-the-counter or prescription antihistamines, corticosteroids, antibiotics and antifungal topical creams or ointments may be used. The kinds of treatment are often similar for the different types of eczema. Therefore, in some cases distinguishing between the types is not necessary. Some patients with severe or chronic (ongoing) eczema may wish to consult a dermatologist for treatment. Other treatments, according to type of eczema, include: Atopic dermatitis. Corticosteroid creams and lotions are used to ease symptoms. Recently, topical medications called immunomodulators have been used to treat atopic dermatitis. They affect the immune system and help maintain normal skin texture while reducing flare-ups. Patients whose skin cracks open may use wet dressings with a mild astringent to help contract the skin, reduce secretions and prevent infection. Contact dermatitis. Avoidance of the source of irritation or allergy is the best treatment. Corticosteroid creams or wet dressings provide moisture to the skin that may relieve redness and itching. It may take up to four weeks for this type of dermatitis to clear. Neurodermatitis. Treatment is focused on getting the patient to avoid scratching or further aggravating the skin. Dressings, corticosteroid lotions and creams, and wet compresses may help soothe skin by reducing inflammation and relieving itch. Sedatives and tranquilizers are also sometimes used to prevent patients from scratching. Seborrheic dermatitis. Patients are instructed to frequently shampoo while also carefully rinsing the scalp. A specific shampoo may be suggested that contains ingredients such as tar, zinc pyrithione and salicylic acid. Corticosteroid creams and lotions may soothe the skin and relieve itching. Stasis dermatitis. Treatment focuses on preventing fluid from accumulating in the ankles and lower legs for extended periods. Patients may have to wear elastic support hose or require varicose vein surgery. Wet dressings can also soften the thickened skin and control infection. Perioral dermatitis. Several months of treatment with oral antibiotics is typically recommended. A mild corticosteroid cream may also be prescribed. Latex dermatitis. Avoidance is the best treatment for latex dermatitis. This entails ensuring that the patient does not use or come into contact with latex-based products. Dyshidrotic dermatitis. Topical corticosteroids are usually used to control mild breakouts. More substantial breakouts can be controlled with oral steroids or treatments of PUVA phototherapy (ultraviolet light). Patients with eczema may also need antibiotics or other treatments if they are diagnosed with an associated secondary infection. Prevention methods for eczema Patients with the form of eczema known as contact dermatitis are encouraged to avoid coming into contact with irritating substances – such as poison ivy or harsh soaps – that may trigger the condition. Many other forms of eczema can be partially or fully prevented by avoiding dry skin. Tips for helping to achieve this goal include: Bathe less frequently. When possible, people may opt to bathe just two or three times a week, limiting themselves to 15 minutes of bathing in warm – rather than hot – water. Use mild soaps or synthetic detergents. Mild soaps clean without excessively removing natural oils. Soap substitutes (synthetic detergents) in bar, gel and liquid forms dry the skin less than deodorant and antibacterial soaps. Soap should be used on the face, underarms, genital areas, hands and feet. Clear water can be used elsewhere. Patients should avoid the use of body sponges and washcloths, which can irritate the skin. The hands should be used instead to gently apply soap to the body. Dry skin carefully. Brush the skin rapidly with the palms of the hands, or gently pat skin dry with a soft towel after bathing. Moisturize skin. A moisturizer should be applied whenever the skin appears dry. Lotions should be avoided because they often contain fragrances, alcohol and other irritants which can aggravate the skin. Creams, which contain oil and water, and ointments, which contain only oil, are better choices. It is particularly important to apply moisturizers after a bath, especially on the legs, arms, back and the sides of the body. Applying these products to the skin within three minutes of bathing, while the skin is still damp, helps seal in moisture. Wear gloves in the winter. Exposing skin to cold air with little humidity can dry out skin. Other tips for preventing eczema or for reducing symptoms associated with the disease include avoiding: Substances that provoke allergies (allergens), which may trigger atopic dermatitis. Tight-fitting, rough or scratchy clothing. This can irritate the skin. Wool, linen and some synthetics are especially likely to irritate the skin. Cotton and cotton blends are better choices. Scratching the rash. Patients who find it difficult to control this urge should cover the area with a dressing or even wear gloves at night to minimize damage to the skin caused by scratching. Keeping short fingernails can help decrease the damage scratching causes the skin. Strenuous exercise during a flare-up. Sweating can irritate the rash. Mental and physical stress. Stress can trigger flare-ups. Stress management techniques, such as deep breathing, yoga and meditation can help patients reduce their stress levels. Patients may also benefit from joining an eczema support group. Contact with solvents and soaking in water. People who use solvents or who use water to clean should wear gloves to protect the skin on their hands. Sudden changes in temperature and humidity. An increase in temperature can lead to sweating and a decrease in humidity can dry the skin. In addition, patients with eczema should choose facial cleansers and makeup with care. Products labeled as “hypoallergenic”, “noncomedogenic” and “nonacnegenic” are least likely to irritate the skin. When using a product for the first time, patients should test the product on a small patch of skin that is clear and not irritated.

Deal with Acne

Reviewed By:
Rana Rofagha Sajjadian, M.D., AAD
Kimberly Bazar, M.D., AAD

About acne

Acne is a very common skin disorder of the pilosebaceous units (PSUs). PSUs consist of sebaceous glands that connect to hair follicles (canals) lined with keratinocytes. The sebaceous glands produce sebum (skin oil). Acne is often inflammatory and is characterized by comedones (clogged pores) and pimples (papules and pustules), due in part to the excessive production of sebum. Acne is not a serious medical condition, and can usually be kept under control with treatment. Although scarring is common, treatment during and after an outbreak can help. When excessive amounts of sebum and dead keratinocytes accumulate in the hair follicle, they often solidify as a soft plug. The plug may be complete and form a whitehead (closed comedone) or may be incomplete and form a blackhead (open comedone). These plugged, sebum–filled follicles allow overgrowth of Propionibacterium acnes (P. acnes), which are skin bacteria that are normally present in hair follicles. P. acnes break the sebum down into substances that irritate the skin and cause inflammation. This inflammation may lead to pimples, cysts or nodules. Although acne is not a serious medical condition, it often causes great emotional distress. It may have a significant impact on social relationships, self–esteem or a person’s outlook on life. Many acne sufferers demonstrate social withdrawal, poor body image and feelings of depression, anger and frustration. Acne sufferers may also experience a higher rate of unemployment. Acne myths, such as the belief that acne is linked to poor hygiene, may contribute to this poor social regard. Acne is the most common skin condition affecting people worldwide. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), nearly 85 percent of all people between the ages of 12 and 24 develop acne and nearly 17 million people in the United States have acne. Acne is most common in teenagers and usually occurs in puberty (typically between the ages of 10 and 13), when androgens (male sex hormones) increase in both males and females. This increase in androgens causes the sebaceous glands to become bigger and more active. Although most commonly seen in teenagers, acne can affect people of all ages – even infants. Onset may occur in adulthood or breakouts that began during adolescence may continue into adulthood. Most cases of acne last between five to 10 years. Typically, the severity of acne decreases by the age of 30, but this is not always the case. It is not uncommon for people in their 20s or 30s to have the condition, and it may continue to affect people in their 40s and 50s. During adolescence, acne is more common in males than in females. In adulthood, it affects women more often than men. Types and differences of acne There are many different types of acne. “Common” acne (acne vulgaris) can be divided into four categories according to severity: Type 1. Predominantly comedones (whiteheads and blackheads) with an occasional small pimple (papule or pustule). Type 1 does not involve scarring. Type 2. Comedones and more numerous pimples, mainly facial. Type 2 involves mild scarring. Type 3. Numerous comedones and pimples, spreading to the back, chest and shoulders. Type 3 involves an occasional cyst or nodule and moderate scarring. Type 4. Numerous large cysts and nodules on face, neck and upper trunk. Type 4 involves severe scarring. Another common form of acne is acne rosacea (rosacea), which includes facial discoloration (reddening). Other types of less common acne may be characterized by severity and symptoms or by causes. Types of acne categorized by severity and symptoms include: Acne indurate. Common acne with chronic, discolored, hardened surfaces. Acne keratosa. Acne that occurs at the corners of the mouth where nodules crust over to form horny plugs. Acne ciliaris. Acne that occurs at the edges of the eyelids. Acne papulosa. Acne with papule formation and very little inflammation. Acne varioliformis. Acne with pustules occurring mostly on the temples and front of the scalp and lesser occurrence on the chest, back or nose. Acne atrophica. Acne with residual pitting and scarring. Acne pustulosa. Acne with pustule formation and subsequent deep scars. Acne urticaria. Acne with itching hives (small swellings on the skin). Acne conglobata. Acne with abscesses (pus pockets), cysts and depressions that leave scars. Cystic acne. Acne with cysts. Acne fulminans. Rare type of acne marked by inflamed, tender, crusting lesions on the upper trunk and face. Acne fulminans occurs suddenly and typically affects adolescent males. It is often accompanied by fever, high levels of white blood cells and an elevated sedimentation rate. It is occasionally accompanied by inflammation in several joints. Acne keloidalis nuchae. Also called keloid acne. Acne keloidalis involves infection of the hair follicles at the back of the neck. This type of acne causes scars and thickening of the skin, and almost exclusively affects African American men. Types of acne categorized according to cause include: Halogen acne. Acne that occurs after exposure to halogens (e.g., bromides, iodine, chlorine). Chloracne. Type of halogen acne that occurs after exposure to chlorinated chemicals, such as the chlorine used to treat pool water. Petroleum acne. Acne that occurs in individuals who work with petroleum and oils. Steroid acne. Acne that results after the systemic or topical use of steroids, including corticosteroids and anabolic steroids. Often occurs predominantly on the upper back and shoulders. Summer acne. Also called tropical acne. Summer acne occurs in hot, humid weather or is made worse by such weather. It predominantly affects the neck, chest, back and legs, and often occurs in individuals unaccustomed to such climates. In addition, acne occurring among newborns and infants is known as acne neonatorum. Risk factors and causes of acne The actual cause of acne is not known. Contributing factors include: Overproduction of sebum (skin oil) Irregular shedding of dead skin cells Buildup of bacteria Inflammation or infection There are many factors that influence these contributing factors and outbreaks after onset, including: Hormonal changes. These may include changes due to: Puberty. Involves increased secretion of androgens (male sex hormones) in both males and females, resulting in increased size and activity of sebaceous glands. Menstruation. Women and girls may experience acne outbreaks two to seven days prior to their periods. Pregnancy. May improve or worsen acne. Oral contraceptives. Women starting or stopping birth control pills may experience an improvement or worsening of acne. Stress. Stress may have an affect on hormones, causing individuals undergoing high levels of stress to experience an outbreak or worsening of acne. Certain medications. Medications such as corticosteroids, anabolic steroids (such as those used by athletes) and barbiturates may lead to acne outbreaks. Heredity. Severe acne may have a genetic component. Allergies and sensitivities. In some people, food and other allergies or intolerances may cause an outbreak of acne. Also, some individuals are more sensitive to the bacteria that cause acne. Certain chemicals and other substances. Exposure to halogens (e.g., chlorine, fluorine, iodine, bromine) and tar may lead to acne outbreaks. Direct skin exposure to greasy or oily substances (e.g., from scalp or hair, mineral or cooking oils) and certain cosmetics may cause acne. Friction or pressure on skin. Friction and pressure, such as that caused by telephones, helmets, tight collars and backpacks, may lead to acne outbreaks. Irritation from picking or squeezing acne blemishes, scrubbing the skin too hard or using harsh soaps or chemicals may also cause or worsen acne. Environmental factors. Humidity, pollution, changes in the season and other environmental factors may lead to an outbreak of acne. Many factors are widely believed to cause or worsen acne when they actually do not. These include: Particular foods. Chocolate and greasy foods (e.g., French fries, pizza) are often blamed for acne. In reality, they have no influence on the condition unless an individual has an allergy or intolerance to these items. Poor hygiene. Acne is caused by a build-up of excessive amounts of sebum. Dirt and sweat are not involved. The belief that poor hygiene is related to acne has led many individuals to harshly scrub their skin to get rid of or to prevent acne. This practice can cause irritation and actually make acne worse. Signs and symptoms of acne Acne is characterized by an outbreak of lesions on the skin. These lesions include: Whiteheads (closed comedones). The openings of the hair follicles become clogged and completely blocked. The soft plug is a white color. These are noninflammatory. Blackheads (open comedones). The openings of the hair follicles become clogged and partially blocked. The plug darkens and is open to the surface of the skin. These are noninflammatory. Pimples (papules and pustules). Raised, reddish spots with white centers that signal inflammation or infection in the follicle. These may be without pus (papules) or may contain pus (pustules). They may be tender or painful. Nodules. Solid, raised reddish bumps. Cysts. Thick lumps beneath the skin formed by the build–up of secretions deep in the hair follicle. Acne can occur anywhere on the body, but it is most common in areas with high concentrations of sebaceous glands (e.g., face, neck, chest, shoulders, upper back). Mild (superficial) acne is characterized by whiteheads or blackheads and a few small, mildly irritated pimples and usually do not leave scars. Severe (deep, cystic) acne is characterized by many large, painful nodules and cysts that may join together under the skin into even larger abscesses (pus pockets). Severe acne often leaves scars. Acne scars may last a lifetime or fade over time. They may appear in many forms, including: Tiny, deep holes (ice pick scars) Wide pits of varying depth Large, irregular indentations Raised thickened tissue (hypertrophic scars or keloids) Although over-the-counter acne medications can help treat minor cases of acne, more serious forms of acne require a physician’s attention. Patients should consult with a dermatologist under the following circumstances: Acne affects the patient emotionally. Over-the-counter products fail to improve symptoms. Scars form after lesions clear. Nodules are present, in addition to whiteheads, blackheads, and reddened spots on the skin. Darker patches appear on the skin where acne lesions have cleared (in people with dark skin). People concerned about their acne should contact a dermatologist as early as possible. Early treatment often leads to the best results and helps prevent scarring. Diagnosis and treatment of acne Acne is typically treated by a dermatologist (skin specialist). The diagnosis of acne relies upon the patient’s medical history and a physical examination. In most cases, acne is obvious and does not require any additional testing. However, in rare cases the sudden onset of severe acne in older adults may be a sign of a more serious underlying condition, such as polycystic ovarian syndrome (an endocrine and hormonal disorder). In some cases, an acne-like rash can develop as the result of make-up, lotions or medications. Therefore, it is important for patients to provide their physician with an accurate history of all products used on the skin and any medications taken. The goal of acne treatment is to minimize scarring, prevent further eruptions of blemishes and improve those that are already present. Treatments that work for one patient may not work for another. As a result, certain considerations need to be made when deciding upon treatment. These include: Acne severity Types of lesions present Patient's age Patient's skin type Patient’s overall health and medical history Patient’s tolerance for specific medications, procedures or therapies Patient and physician’s expectations for the course of the condition Patient’s opinion or preference Acne treatments may be local or systemic and generally work by reducing the inflammation in the skin, speeding up skin cell turnover, fighting bacterial infection or a combination of these methods. It is normal to see little or no improvement in the acne for six to eight weeks after starting a medication, and in many cases the acne gets worse before it gets better. When a patient’s acne fails to improve after several weeks of treatment, their physician may change treatment methods Patients should continue using their acne medication until instructed otherwise, regardless of whether the skin has cleared. Sudden discontinuation of acne medication can lead to a recurrence of acne several weeks later. In some cases, acne may improve with exposure to a small amount of sun. However, many treatments make the skin more susceptible to sun damage, so patients on these therapies are typically advised to avoid sun exposure. Acne treatments are numerous and varied. Mild acne requires less extensive treatment and often clears up quickly and with no ill effects. Severe acne may require more powerful treatments that may have serious side effects. Most patients will benefit from a combination of two or more therapies. Topical treatments are widely available both over-the-counter and in prescription form. Acne lotions, gels and washes may dry up sebum, kill the acne bacteria or promote the proper sloughing of dead skin cells. Over–the–counter topical treatments are generally mild. Their active ingredients may include benzoyl peroxide, one of the most commonly used topical treatments. Other ingredients include alcohol and acetone, which are used together to reduce oil concentrations and help kill bacteria. Stronger prescription lotions may be prescribed for moderate to severe acne. These are typically retinoids (vitamin A derivatives) that work by promoting cell turnover and preventing the clogging of hair follicles or topical antibiotics. Topical antibiotics work by killing the bacteria that lead to acne and reducing inflammation. Oral antibiotics may be prescribed for moderate to severe acne. These reduce bacteria and fight inflammation, but may take months to work. They are often used in combination with topical products. Many oral antibiotics (e.g., isotretinoin) should not be taken by women who are or may become pregnant. When acne outbreaks coincide with a woman’s monthly period, oral contraceptives may help to control the acne. Large, inflamed nodules or cysts may be treated by an injection with corticosteroids. It typically takes three to five days after the injection to clear up the treated nodule or cyst. Physical treatments for acne and the scars left by acne include: Extraction of comedones. A whitehead or blackhead is opened and extracted with a sterile, pen-sized device, fine needle or blade. Drainage and surgical extraction. Also called “acne surgery,” this is the drainage and extraction of large cysts. It reduces the pain and decreases the likelihood of scarring. Chemical peels. Chemicals (e.g., glycolic acid) are applied to the skin in a physician’s office to loosen blackheads and whiteheads and decrease acne papules. This method may eliminate superficial scars by peeling away damaged skin. Microdermabrasion. Aluminum oxide crystals pass through a vacuum tube to gently scrape away scarred tissue. Multiple treatments may be required for subtle results. Dermabrasion. A rotating wire brush or spinning diamond instrument is used to wear down the surface of the skin. As the skin heals, a smoother layer replaces the abraded skin. This healing usually takes from 10 days to three weeks. Subcision. Small cuts are made under the skin to release scar tissue. This often allows skin to resume normal contours and may cosmetically improve wide, indented scars. Excision and punch replacement graft. A depressed acne scar is surgically removed and replaced with a patch of skin from elsewhere on the patient’s body. Soft tissue fillers. Small quantities of soft tissues (e.g., collagen, polymer implants, fat) are injected under the skin to elevate depressed scars to skin level. Laser resurfacing. Short pulses of intense light are used to remove the outer, damaged layer of skin and tighten the middle layer, leaving skin smoother. This procedure can usually be performed in the dermatologist’s office and may take from a few minutes to an hour. It may take from three to 10 days to heal. Prevention methods for acne There are several steps that may be taken to prevent acne outbreaks. These may also help prevent current acne from getting worse. They include: Washing problem areas with gentle cleansers. It is important to wash the face twice daily with a gentle cleanser. It is also important to remove all makeup from the skin. However, excessive washing and scrubbing can irritate the skin. People with acne are typically advised to avoid facial scrubs, astringents, masks and skin abrasion, as these may irritate the skin and cause or worsen acne. Shampooing hair frequently. This is particularly important when acne tends to develop around the hairline. Oils from the hair and scalp may contribute to acne. Avoiding irritants. Oily or greasy substances (e.g., cosmetics, sunscreens, hair styling products, acne concealers) may contribute to the development or worsening of acne. Using products labeled “water based” or “noncomedogenic” (does not block pores), "oil-free" or "nonacnegenic" may help avoid this. Patients should also keep hair styling products, such as hairsprays and gels, away from the face. Exercising caution around problem areas. This includes: Keeping hair off the face Not resting hands or objects (e.g., telephone receivers, headphones) on the face Avoiding tight clothing and hats Not picking or squeezing blemishes. This can cause infection or scarring and most acne will clear up without this form of intervention. Shaving carefully. Razors can irritate blemishes. Therefore, patients should shave gently and only when necessary. Ongoing research regarding acne Ongoing research is currently investigating many factors in the treatment of acne, including: New medications. New drugs to treat acne, particularly new topical antibiotics, are being researched. The bacteria that causes acne is becoming resistant to some antibiotics, so other means of treating acne are being evaluated. New procedures. New laser treatments are currently under investigation. Many of these show a great deal of promise.

A Skin Allergy to Nickel: Signs, Symptoms, and Solutions

By Crystal sky Experience

" When my son was just a baby he developed red circles where the snaps of his pajamas came in contact with his skin, but I didn't know why, and a skin allergy didn't enter my mind. I thought maybe the snaps were rough, or maybe he had laid on them, and it wasn't until he started wearing jeans with metal buttons that I figured out he was allergic to nickel and other types of cheap metal. I began dressing him in undershirts to avoid a problem, and I didn't think of the possibility of a skin allergy until he was a little older.

Allergy Symptoms

My son was a toddler when I began dressing him in jeans, and he developed a rash on his abdomen that looked similar to a serious burn or a large blister. The location of this rash was where the metal button on his jeans came in contact with his skin. I didn't know what the problem was right away, but after it began occurring on a regular basis, I figured out he was allergic to nickel and other types of cheap metal.

My son is now 12 years old, and I recently asked him to describe how it feels to have a rash caused by cheap metal such as nickel, and he said it's quite painful at times. Not only does it hurt since the skin is peeling, inflamed, and very irritated, but clothing irritates the area even more and causes additional pain. It's important for those who think they are allergic to nickel or other types of cheap metal to prevent contact with nickel or other types of metal to avoid painful skin eruptions in the first place.

Solutions for Snaps and Metal Buttons

Since my son practically lives in jeans with cheap metal snaps, probably made from nickel, I had to find a solution to prevent the snaps from coming in contact with his skin and causing painful allergic reactions. My ex husband came up with the idea of covering the backs of the snaps with duct tape, and this plan works like a charm. Duct tape is a very versatile product, and it enables my son to wear his favorite jeans with cheap metal buttons and snaps. We cut squares of duct tape to cover the buttons and snaps, and since the adhesive is strong, the squares stay on, even while washing and drying his clothes. When the squares begin peeling off, we replace them with new ones.

Items We Take for Granted

Before I realized my son had a skin allergy to nickel and other cheap types of metal, I took for granted many everyday items. Because of his skin allergy, my son can't wear a watch since most have cheap metal buckles. Because of his allergy to nickel, my son can't wear most types of belts. Belt buckles made of nickel or studded with other cheap types of metal cause seriously painful blister-like abrasions. He can't wear neck chains or many other types of jewelry either, unless they're made from titanium or gold. Because of his allergy to nickel and other cheap types of metal, my son couldn't have the eyeglasses he wanted, and I had to purchase plastic frames that he didn't really want. While he slept one night, his hand accidentally came in contact with his cheap metal bed frame, and as a result of his skin allergy, he developed a painful rash on his hand. These are just some of the experiences my son has had, and even ordinary everyday items can cause serious problems for those with an allergy to nickel and other cheap types of metal."

Prebiotics Can Cut Development Of Skin Allergy In Babies At High Risk

Prebiotics can cut the chances of developing atopic dermatitis in babies at high risk of the disorder, suggests a study published ahead of print in the Archives of Disease in Childhood .

Human breast milk contains natural prebiotics (oligosaccharides), which promote the growth of bacteria, such as lactobacilli and bifidobacteria that boost the development of a healthy immune system.This can help prevent allergies in a very young child.

Researchers developed an infant formula based on the prebiotic content of human breast milk and tested it out on a group of babies one of other of whose parents had atopic eczema, or allergic rhinitis, or asthma.

All the mothers were advised to breastfeed their babies, all of whom were born after a normal length pregancy. But for those unable to start or continue, their babies were divided into two groups, with 102 given a prebiotic formula feed and 104 given a normal formula.

The babies were seen on a monthly basis up to the age of 6 months, and their parents kept a symptom diary.

Over the six months, only 10 babies fed the prebiotic formula developed atopic dermatitis, compared with 24 fed the normal formula. An assessment of stool samples from 98 of the babies showed a significant increase in bifidobacteria in those fed the prebiotic feed.

This strongly suggests that formula feed supplemented with prebiotics can modify the bowel bacteria and so reduce the chance of developing atopic dermatitis among children at high risk of the disorder

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Article adapted by Medical News Today from original press release.
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Contact: Emma Dickinson
BMJ Specialty Journals

Milk And Egg Allergies Harder To Outgrow

Considered "transitional" a generation ago, milk and egg allergies now appear to be more persistent and harder to outgrow, according to new research from the Johns Hopkins Children's Center.

In what are believed to be the largest studies to date of children with milk and egg allergies, researchers followed more than 800 patients with milk allergy and nearly 900 with egg allergy over 13 years, finding that, contrary to popular belief, most of these allergies persist well into the school years and beyond. Reports on the two studies appear in the November and December issues of the Journal of Allergy and Clinical Immunology.

"The bad news is that the prognosis for a child with a milk or egg allergy appears to be worse than it was 20 years ago," says lead investigator Robert Wood, M.D., head of Allergy & Immunology at Hopkins Children's. "Not only do more kids have allergies, but fewer of them outgrow their allergies, and those who do, do so later than before."

Researchers caution that their findings may reflect the fact that relatively more severe cases end up at Hopkins Children's, but they believe there is a trend toward more severe, more persistent allergies.

The findings also give credence to what pediatricians have suspected for some time: More recently diagnosed food allergies, for still-unknown reasons, behave more unpredictably and more aggressively than cases diagnosed in the past. "We may be dealing with a different kind of disease process than we did 20 years ago," Wood says. "Why this is happening we just don't know."

Earlier research suggested that three-quarters of children with milk allergy outgrew their condition by age 3, but the Johns Hopkins team found that just one-fifth of children in their studies outgrew their allergy by age 4, and only 42 percent outgrew it by age 8. By age 16, 79 percent were allergy-free.

Similar trends were seen in the egg-allergy group. Only 4 percent outgrew this allergy by age 4, 37 percent by age 10, and 68 percent by age 16.

The Hopkins Children's team found that a child's blood levels of milk and egg antibodies-the immune chemicals produced in response to allergens-were a reliable predictor of disease behavior: The higher the level of antibodies, the less likely it was that a child would outgrow the allergy any time soon. Pediatricians should use antibody test results when counseling parents about their child's prognosis, researchers say.

One encouraging finding: Some children lost their allergies during adolescence, which is later than believed possible, suggesting that doctors should continue to test patients well into early adulthood to check if they may have lost their allergies.

Milk and egg allergies are the two most common food allergies in the United States, affecting 3 percent and 2 percent of children, respectively.

Co-investigators in the two studies: Justin Skripak, M.D., Jessica Savage, M. D., Elizabeth Matsui, M.D., M.H.S, Kim Mudd, R.N., all of Hopkins Children's.

The studies were funded in part by the National Institutes of Health and supported by the Eudowood Foundation, the Food Allergy Initiative and Julie and Neil Reinhard. Wood is a consultant for Dey Pharmaceuticals and has received support from Merck and Genentech.

Founded in 1912 as the children's hospital of the Johns Hopkins Medical Institutions, the Johns Hopkins Children's Center offers one of the most comprehensive pediatric medical programs in the country, treating more than 90,000 children each year. U.S. News & World Report ranks Hopkins Children's among the top three children's hospitals in the nation. Hopkins Children's is Maryland's only state-designated Trauma Service and Burn Unit for pediatric patients. It has recognized Centers of Excellence in 20 pediatric subspecialties including cardiology, transplant, psychiatric illnesses and genetic disorders. For more information, please visit: http://www.hopkinsmedicine.org

Johns Hopkins Medicine
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Babies Exposed To Secondhand Smoke Have Higher Risk Of Developing Allergies

New research released has found that babies exposed to secondhand smoke are almost twice as likely to develop allergies to inhaled allergens such as animal hair as infants who are not exposed to tobacco smoke. Children whose parents smoke are almost 50% more likely to be allergic to certain foods. [1]

The findings are based on parental survey responses from more than 4000 families about their children's allergies and environmental factors to which they were exposed before and after birth. These included parental smoking, pet dander (animal hair and dead skin) and foodstuffs.

One in 12 mothers smoked throughout pregnancy and one in 8 smoked during part of the pregnancy. The researchers found no evidence that smoking while pregnant affected a child's risk of becoming sensitised to a certain allergen. But there was a dose-response effect for exposure to secondhand smoke during the first weeks of life and markers for sensitisation. Furthermore, the effect of secondhand smoke exposure was stronger among children with non-allergic parents than among those with parents who had allergies.

Amanda Sandford, Research Manager of the health campaigning charity ASH, said:

"This study provides yet more evidence of the need to ensure that babies and young children are not exposed to tobacco smoke. Whilst the development of some allergies may not be fully understood, this research shows that one way of substantially reducing the risk is by banning smoking in the home.

The study adds to the already substantial body of evidence of the harmful impacts of secondhand smoke on children, particularly in the early years of development. [2] Simply restricting smoking to certain rooms does not offer enough protection to infants and families should therefore make every effort to make their homes smokefree to give their children the best possible start in life. "

Notes:

[1] Lannero E et al. Exposure to environmental tobacco smoke and sensitisation in children. Thorax 2007

[2] Going smoke-free. The medical case for clean air in the home, at work and in public places. Royal College of Physicians, London, 2005

http://www.ash.org.uk

Five Great Ways To Be Allergy-Free

By Richard Shames, M.D.& Karilee Shames, R.N., Ph.D.

About.com Health's Disease and Condition content is reviewed by our Medical Review Board

As allergy season progresses, you may be wishing for more effective relief. People with thyroid and other autoimmune problems generally have greater-than-average difficulty with their allergic symptoms.

There are, however, some very useful natural remedies ideal for your particular needs. These may be utilized in addition to, and often instead of, the harsher and more expensive chemical medicines.

Below is a sampling of successful maneuvers from twenty-five years of our thyroid and general medical practice. Please consider this list a menu rather than a prescription.

REVITALIZE YOUR VITAMINS - Make sure you are taking a hypoallergenic multivitamin with chelated minerals. Good daily doses of superb additional items are 500 mg of the B vitamin pantothenic acid; 2000 mg of ester-type vitamin C; 1200 mg of the bioflavenoid quercetin; and four capsules of mullein. Excellent proprietary items include the herb Perilla Seed from Metagenics. Two pills daily lowers your allergy threshold, while two daily of Butterbur from Life Extension make an effective decongestant.

IMPROVE YOUR INDOOR AIR - Night time breathing is a surprising factor in daytime allergy symptoms. Have your windows closed from mid-night to noon to keep most of the pollen out. Air conditioning is also a great help. Do frequent laundry runs and vacuuming of your sleeping space. Be ruthless with bedroom clutter, so as to eliminate dust catchers, such as throw rugs, extra pillows, books, papers, and junk. Equally important: always sleep near a HEPA air filter.

EAT YOUR WAY TO SUCCESS - Paying attention to your food sensitivities has a way of making the pollen allergies better. You are likely to be overtly sensitive to whatever has disagreed with you in the past. Moreover, you probably have a hidden sensitivity to the food you crave most, be it bread, chocolate, corn chips, or dairy. Eating a “sensitive” food less frequently (perhaps only every other day or every third day) will augment your allergy relief. For added benefit, try eating more natural whole food, and less artificial sweeteners. Synthetic chemicals are like a metabolic monkey wrench for allergy sufferers.

PURSUE POSITIVE THINKING - How could this help? Simple: Our immune system over-reaction to the microenvironment corresponds to our being overly “defensive” in the social environment. That connection has now been confirmed by researchers. Start doing whatever it will take for you to be less fearful or worried or anxious. This can be quite a task, but well worth it in terms of an immune system that has far fewer hair-trigger responses to pollen and dust.

HONOR YOUR HORMONE BALANCE -- This could be your most important remedy of all. Fine tune your thyroid-adrenal-sex gland levels, and you may not need anything else. Well-balanced hormones lead to a better balanced immune system. Why not check these three glands with one inexpensive self-ordered home saliva test? (Tests are available from www.canaryclub.org) Sensitive saliva testing may show a correctable imbalance, despite a good health regimen and/or normal blood tests. You can re-adjust your levels, often with simple over-the-counter remedies, and your allergies will generally be quite improved. (One of many information sources for non-prescription hormone balancers is our book, Feeling Fat, Fuzzy, or Frazzled? Hudson/Penguin, 2005)

Here’s wishing you less sneezing, less dripping, and great lasting relief.

Richard L. Shames MD & Karilee H. Shames PhD, RN are authors of two popular books for thyroid patients, Thyroid Power and Feeling Fat, Fuzzy and Frazzled?. Both experts provide telephone coaching for optimal wellness. More information is available about their coaching sessions at their site.

Researcher develops allergy-free peanuts

by Jennifer Guevin

People with life-threatening allergies to peanuts might be able to rest easy at their friendly neighborhood Thai restaurants soon, if research announced this week proves true.

A release from North Carolina Agricultural and Technical State University says researcher Mohamed Ahmedna has developed whole, roasted peanuts in which the allergen is completely inactivated and that serum from people with severe peanut allergies did not react to the processed peanuts at all. The university paper does not explain the process at all. However, it claims the technique inactivates peanut allergens without degrading the taste or quality of treated peanuts.

Between 1.5 million and 3 million Americans have a peanut allergy (the number varies widely among different studies), and peanuts account for 80 percent of fatal or near-fatal allergic reactions each year, according to the Mayo Clinic. And the number of people with peanut and tree nut allergies has increased dramatically in recent years. Peanut allergies can be particularly dangerous because food in restaurants and manufacturing plants often comes into contact with equipment contaminated with traces of peanut oil.

The university is looking for a way to commercialize the allergy-free peanuts, which could be very good news for peanut-allergic people, many of whom have to cautiously inspect package labels and inquire about the use of peanut oil in restaurant kitchens.

Getting to know Allergy

Allergy is a disorder of the immune system that is often called atopy. Allergic reactions occur to environmental substances known as allergens; these reactions are acquired, predictable and rapid. Strictly, allergy is one of four forms of hypersensitivity and is called type I (or immediate) hypersensitivity. It is characterized by excessive activation of certain white blood cells called mast cells and basophils by a type of antibody, known as IgE, resulting in an extreme inflammatoryeczema, hives, hay fever, asthma, food allergies, and reactions to the venom of stinging insects such as wasps and bees.^[1] response. Common allergic reactions include

Mild allergies like hay fever, are highly prevalent in the human population and cause symptomsallergic conjunctivitis and runny nose. Similarly, conditions such as asthma are common, in which allergy plays a major role. In some people, severe allergies to environmental or dietary allergens, or to medication, occur that may result in life-threatening anaphylactic reactions and potentially death.

A variety of tests now exist to diagnose allergic conditions; these include testing the skin for responses to known allergens or analyzing the blood for the presence and levels of allergen-specific IgE. Treatments for allergies include allergen avoidance, use of antihistamines, steroids or other oral medications, immunotherapy to desensitize the response to allergen, and targeted therapy.

Classification and history

The concept "allergy" was originally introduced in 1906 by the Viennese pediatrician Clemens von Pirquet, after noting that some of his patients were hypersensitive to normally innocuous entities such as dust, pollen, or certain foods.^[2] Pirquet called this phenomenon "allergy" from the Greekallos meaning "other" and ergon meaning "work".^[3] Historically, all forms of hypersensitivity were classified as allergies, and all were thought to be caused by an improper activation of the immune system. Later, it became clear that several different disease mechanisms were implicated, with the common link to a disordered activation of the immune system. In 1963, a new classification scheme was designed by Philip Gell and Robin Coombs that described four types of hypersensitivity reactions, known as Type I to Type IV hypersensitivity.^[4] With this new classification, the word "allergy" was restricted to only type I hypersensitivities (also called immediate hypersensitivity), which are characterized as rapidly developing reactions. words

A major breakthrough in understanding the mechanisms of allergy was the discovery of the antibody class labeled immunoglobulin E (IgE) - Kimishige Ishizaka and co-workers were the first to isolate and describe IgE in the 1960s.^[5]

Signs and symptoms

Common symptoms of allergy
Affected organ	Symptom
Nose	swelling of the nasal mucosa (allergic rhinitis)
Sinuses	allergic sinusitis
Eyes	redness and itching of the conjunctiva (allergic conjunctivitis)
Airways	Sneezing, bronchoconstriction, wheezing and dyspnea, sometimes outright attacks of asthma, in severe cases the airway constricts due to swelling known as anaphylaxis
Ears	feeling of fullness, possibly pain, and impaired hearing due to the lack of eustachian tube drainage.
Skin	rashes, such as eczema and hives (urticaria)
Gastrointestinal tract	abdominal pain, bloating, vomiting, diarrhoea

Many allergens are airborne particles, such as dust or pollen. Allergic rhinitis, also known as hay fever, occurs in response to airborne pollen, and causes irritation of the nose, sneezing, and itching and redness of the eyes.^[6] Inhaled allergens can also lead to asthmatic symptoms, caused by narrowing of the airways (bronchoconstriction) and increased production of mucus in the lungs, shortness of breath (dyspnea), coughing and wheezing.^[7]

Aside from these ambient allergens, allergic reactions can result from foods, insect stings, and reactions to medications like aspirin, and antibiotics such as penicillin. Symptoms of food allergy include abdominal pain, bloating, vomiting, diarrhoea, itchy skin, and swelling of the skin during hives or angiooedema. Food allergies rarely cause respiratory (asthmatic) reactions, or rhinitis.^[8] Insect stings, antibiotics and certain medicines produce a systemic allergic response that is also called anaphylaxis; multiple systems can be affected including the digestive system, the respiratory system, and the circulatory system.^[9][10][11] Depending of the rate of severity, it can cause cutaneous reactions, bronchoconstriction, edema, hypotension, coma and even death. This type of reaction can be triggered suddenly or the onset can be delayed. The severity of this type of allergic response often requires injections of epinephrine, sometimes through a device known as the Epi-Pen auto-injector. The nature of anaphylaxis is such that the reaction can seemingly be subsiding, but may recur throughout a prolonged period of time. ^[11]

Substances that come into contact with the skin, such as latex are also common causes of allergic reactions, known as contact dermatitis or eczema.^[12] Skin allergies frequently cause rashes, or swelling and inflammation within the skin, in what is known as a "wheal and flare" reaction characteristic of hives and angioedema.^[13]

Cause

Risk factors for allergy can be placed in two general categories, namely host and environmentalheredity, sex, race and age, with heredity being by far the most important. There are recent increases in the incidence of allergic disorders, however, that cannot be explained by genetic factors alone. The four main candidate environmental factors are alterations in exposure to infectious diseases during early childhood, environmental pollution, allergen levels, and dietary changes.^[14] factors. Host factors include

Genetic basis

Allergic diseases are strongly familial: identical twins are likely to have the same allergic diseases about 70% of the time; the same allergy occurs about 40% of the time in non-identical twins.^[15][16] and their allergies are likely to be stronger than those from non-allergic parents. However some allergies are not consistent along genealogies; parents who are allergic to peanuts, may have children who are allergic to ragweed, or siblings that are allergic to different things. It seems that the likelihood of developing allergies is inherited and due to some irregularity in the way the immune system works, but the specific allergen, which causes the development of an allergy, is not.^[16] Allergic parents are more likely to have allergic children,

The risk of allergic sensitization and the development of allergies varies with age, with young children most at risk.^[17] Several studies have shown that IgE levels are highest in childhood and fall rapidly between the ages of 10 and 30 years.^[17] The peak prevalence of hay fever is highest in children and young adults and the incidence of asthma is highest in children under 10.^[18] Overall, boys have a higher risk of developing allergy than girls,^[16] although for some diseases, namely asthma in young adults, females are more likely to be effected.^[19] Sex differences tend to decrease in adulthood.^[16] Ethnicity may play a role in some allergies, however racial factors have been difficult to separate from environmental influences and changes due to migration.^[16]genetic loci are responsible for asthma in people of Caucasian, Hispanic, Asian, and African origins.^[20] Interestingly, with regards to asthma, it has been suggested that different

Environmental factors

International differences have been associated with the number of individuals within a population that suffer from allergy. Allergic diseases are more common in industrialized countries than in countries that are more traditional or agricultural, and there is a higher rate of allergic disease in urban populations versus rural populations, although these differences are becoming less defined.^[21]

Exposure to allergens, especially in early life, is an important risk factor for allergy. Alterations in exposure to microorganisms is the most plausible explanation, at present, for the increase in atopic allergy.^[14] Since children that live in large families or overcrowded households, or attend day care, have a reduced incidence of allergic disease, a relationship has been proposed between exposures to bacteria and viruses during childhood, and protection against the development of allergy, which has been called – the "hygiene hypothesis".^[21] Exposure to endotoxin and other components of bacteria may reduce atopic diseases.^[22] Endotoxin exposure reduces release of inflammatory cytokines such as TNF-α, IFNγ, interleukin-10, and interleukin-12leukocytes) that circulate in the blood.^[23] Certain microbe-sensing proteins, known as Toll-like receptors, found on the surface of cells in the body are also thought to be involved in these processes.^[24] from white blood cells (

Gutworms and similar parasites are present in untreated drinking water in developing countries, and were present in the water of developed countries until the routine chlorination and purification of drinking water supplies.^[25] Recent research has shown that some common parasites, such as intestinal worms (e.g. hookworms), secrete chemicals into the gut wall (and hence the bloodstream) that suppress the immune system and prevent the body from attacking the parasite.^[26] This gives rise to a new slant on the hygiene hypothesis theory — that co-evolution of man and parasites has led to an immune system that only functions correctly in the presence of the parasites. Without them, the immune system becomes unbalanced and oversensitive.^[27] In particular, research suggests that allergies may coincide with the delayed establishment of gut flora in infants.^[28] However, the research to support this theory is conflicting, with some studies performed in China and Ethopia showing an increase in allergy in people infected with intestinal worms.^[21] Clinical trials have been initiated to test the effectiveness of certain worms in treating some allergies.^[29] It may be that the term 'parasite' could turn out to be inappropriate, and in fact a hitherto unsuspected symbiosis is at work.^[29] For more information on this topic, see Helminthic therapy.

Pathophysiology

The pathophysiology of allergic responses can be divided into two phases. The first is an acute response that occurs immediately after exposure to an allergen. This phase can either subside or progress into a "late phase reaction" which can substantially prolong the symptoms of a response, and result in tissue damage.

Acute response

Degranulation process in allergy.1 - antigen; 2 - IgE antibody; 3 - FcεRI receptor; 4 - preformed mediators (histamine, proteases, chemokines, heparine); 5 - granules; 6 - mast cell; 7 - newly formed mediators (prostaglandins, leukotrienes, thromboxanes, PAF)

In the early stages of allergy, a type I hypersensitivity reaction against an allergen, encountered for the first time, causes a response in a type of immune cell called a T_H2 lymphocyte, which belongs to a subset of T cells that produce a cytokine called interleukin-4 (IL-4). These T_H2 cells interact with other lymphocytes called B cells, whose role is production of antibodies. Coupled with signals provided by IL-4, this interaction stimulates the B cell to begin production of a large amount of a particular type of antibody known as IgE. Secreted IgE circulates in the blood and binds to an IgE-specific receptor (a kind of Fc receptor called FcεRI) on the surface of other kinds of immune cells called mast cells and basophils, which are both involved in the acute inflammatory response. The IgE-coated cells, at this stage are sensitized to the allergen.^[14]

If later exposure to the same allergen occurs, the allergen can bind to the IgE molecules held on the surface of the mast cells or basophils. Cross-linking of the IgE and Fc receptors occurs when more than one IgE-receptor complex interacts with the same allergenic molecule, and activates the sensitized cell. Activated mast cells and basophils undergo a process called degranulation, during which they release histamine and other inflammatory chemical mediators (cytokines, interleukins, leukotrienes, and prostaglandins) from their granules into the surrounding tissue causing several systemic effects, such as vasodilation, mucous secretion, nerve stimulation and smooth musclerhinorrhea, itchiness, dyspnea, and anaphylaxis. Depending on the individual, allergen, and mode of introduction, the symptoms can be system-wide (classical anaphylaxis), or localized to particular body systems; asthma is localized to the respiratory system and eczema is localized to the dermis.^[14] contraction. This causes in

Late-phase response

After the chemical mediators of the acute response subside, late phase responses can often occur. This is due to the migration of other leukocytes such as neutrophils, lymphocytes, eosinophils and macrophages to the initial site. The reaction is usually seen 2-24 hours after the original reaction.^[30] Cytokines from mast cells may also play a role in the persistence of long-term effects. Late phase responses seen in asthma are slightly different from those seen in other allergic responses, although they are still caused by release of mediators from eosinophils, and are still dependent on activity of T_H2 cells.^[31]

Diagnosis

Before a diagnosis of allergic disease can be confirmed, the other possible causes of the presenting symptoms should be carefully considered.^[32] Vasomotor rhinitis, for example, is one of many maladies that shares symptoms with allergic rhinitis, underscoring the need for professional differential diagnosis.^[33] Once a diagnosis of asthma, rhinitis, anaphylaxis, or other allergic disease has been made, there are several methods for discovering the causative agent of that allergy.

Skin testing

For assessing the presence of allergen-specific IgE antibodies, allergy skin testing is preferred over blood allergy tests because it is more sensitive and specific, simpler to use, and less expensive.^[34] Skin testing is also known as "puncture testing" and "prick testing" due to the series of tiny puncture or pricks made into the patient's skin. Small amounts of suspected allergens and/or their extracts (pollen, grass, mite proteins, peanut extract, etc.) are introduced to sites on the skin marked with pen or dye (the ink/dye should be carefully selected, lest it cause an allergic response itself). A small plastic or metal device is used to puncture or prick the skin. Sometimes, the allergens are injected "intradermally" into the patient's skin, with a needle and syringe. Common areas for testing include the inside forearm and the back. If the patient is allergic to the substance, then a visible inflammatory reaction will usually occur within 30 minutes. This response will range from slight reddening of the skin to a full-blown hive (called "wheal and flare") in more sensitive patients. Interpretation of the results of the skin prick test is normally done by allergists on a scale of severity, with +/- meaning borderline reactivity, and 4+ being a large reaction. Increasingly, allergists are measuring and recording the diameter of the wheal and flare reaction. Interpretation by well-trained allergists is often guided by relevant literature.^[35] Some patients may believe they have determined their own allergic sensitivity from observation, but a skin test has been shown to be much better than patient observation to detect allergy.^[36]

If a serious life threatening anaphylactic reaction has brought a patient in for evaluation, some allergists will prefer an initial blood test prior to performing the skin prick test. Skin tests may not be an option if the patient has widespread skin disease or has not avoided antihistamines for several days.

Blood testing

Various blood allergy testing methods are also available for detecting allergy to specific substances. This kind of testing measures a "total IgE level" - an estimate of IgE contained within the patient's serum. This can be determined through the use of radiometric and colormetricimmunoassays. Radiometric assays include the radioallergosorbent test (RAST) test method, which uses IgE-binding (anti-IgE) antibodies labeled with radioactive isotopes for quantifying the levels of IgE antibody in the blood.^[34] Other newer methods use colorimetric or fluorometric technology in the place of radioactive isotopes. Some "screening" test methods are intended to provide qualitative test results, giving a "yes" or "no" answer in patients with suspected allergic sensitization. One such method has a sensitivity of about 70.8% and a positive predictive value of 72.6% according to a large study.^[37]

A low total IgE level is not adequate to rule out sensitization to commonly inhaled allergens.^[38]Statistical methods, such as ROC curves, predictive value calculations, and likelihood ratios have been used to examine the relationship of various testing methods to each other. These methods have shown that patients with a high total IgE have a high probability of allergic sensitization, but further investigation with specific allergy tests for a carefully chosen allergens is often warranted.

Treatment

This article or section deals primarily with the United States and does not represent a worldwide view of the subject. Please improve this article or discuss the issue on the talk page.

There have been enormous improvements in the medical treatments used to treat allergic conditions. With respect to anaphylaxis and hypersensitivity reactions to foods, drugs, and insects and in allergic skin diseases, advances have included the identification of food proteins to which IgE binding is associated with severe reactions and development of low-allergen foods, improvements in skin prick test predictions; evaluation of the atopy patch test; in wasp sting outcomes predictions and a rapidly disintegrating epinephrine tablet, and anti-IL-5 for eosinophilic diseases.^[39]

Traditionally treatment and management of allergies involved simply avoiding the allergen in question or otherwise reducing exposure. For instance, people with cat allergies were encouraged to avoid them. While avoidance may help to reduce symptoms and avoid life-threatening anaphylaxis, it is difficult to achieve for those with pollen or similar air-borne allergies. Strict avoidance still has a role in management though, and is often used in managing food allergies.

Pharmacotherapy

Several antagonistic drugs are used to block the action of allergic mediators, or to prevent activation of cells and degranulation processes. These include antihistamines, cortisone, dexamethasone, hydrocortisone, epinephrine (adrenaline), theophylline and cromolyn sodium. Anti-leukotrienes, such as Montelukast (Singulair) or Zafirlukast (Accolate), are FDA approved for treatment of allergic diseases.^{[citation needed]} Anti-cholinergics, decongestants, mast cell stabilizers, and other compounds thought to impair eosinophil chemotaxis, are also commonly used. These drugs help to alleviate the symptoms of allergy, and are imperative in the recovery of acute anaphylaxis, but play little role in chronic treatment of allergic disorders.

Immunotherapy

Desensitization or hyposensitization is a treatment in which the patient is gradually vaccinated with progressively larger doses of the allergen in question. This can either reduce the severity or eliminate hypersensitivity altogether. It relies on the progressive skewing of IgG antibody production, to block excessive IgE production seen in atopys. In a sense, the person builds up immunity to increasing amounts of the allergen in question. Studies have demonstrated the long-term efficacy and the preventive effect of immunotherapy in reducing the development of new allergy.^[40] Meta-analyses have also confirmed efficacy of the treatment in allergic rhinitis in children and in asthma.^{[citation needed]} A review by the Mayo Clinic in Rochester confirmed the safety and efficacy of allergen immunotherapy for allergic rhinitis and conjunctivitis, allergic forms of asthma, and stinging insect based on numerous well-designed scientific studies.^[41][42] Additionally, national and international guidelines confirm the clinical efficacy of injection immunotherapy in rhinitis and asthma, as well as the safety, provided that recommendations are followed.

A second form of immunotherapy involves the intravenous injection of monoclonal anti-IgE antibodies. These bind to free and B-cell associated IgE; signalling their destruction. They do not bind to IgE already bound to the Fc receptor on basophils and mast cells, as this would stimulate the allergic inflammatory response. The first agent of this class is Omalizumab. While this form of immunotherapy is very effective in treating several types of atopy, it should not be used in treating the majority of people with food allergies.

A third type, Sublingual immunotherapy, is an orally-administered therapy which takes advantage of oral immune tolerance to non-pathogenic antigens such as foods and resident bacteria. This therapy currently accounts for 40 percent of allergy treatment in Europe. In the United States, sublingual immunotherapy is gaining support among traditional allergists and is endorsed by doctors who treat allergy.

Unproven or ineffective treatments

An experimental treatment, enzyme potentiated desensitization (EPD), has been tried for decades but is not generally accepted as effective.^[43] EPD uses dilutions of allergen and an enzyme, beta-glucuronidase, to which T-regulatory lymphocytes are supposed to respond by favouring desensitization, or down-regulation, rather than sensitization. EPD has also been tried for the treatment of autoimmune diseases but again is not FDA approved or of proven effectiveness.^[43]

In alternative medicine, a number of allergy treatments are described by its practitioners, particularly naturopathic, herbal medicine, homeopathy, traditional Chinese medicine and kinesiology. Systematic literature searches conducted by the Mayo Clinic through 2006, involving hundreds of articles studying multiple conditions, including asthma and upper respiratory tract infection showed no effectiveness of any alternative treatments, and no difference compared with placebo. The authors concluded that, based on rigorous clinical trials of all types of homeopathy for childhood and adolescence ailments, there is no convincing evidence that supports the use of alternative treatments.^[44]

Epidemiology

Many diseases related to inflammation such as type 1 diabetes, rheumatoid arthritis and allergic diseases—hay fever and asthma—have increased in the Western world over the past 2-3 decades.^[45] Rapid increases in allergic asthma and other atopic disorders in industrialized nations probably began in the 1960s and 1970s, with further increases occurring during the 1980s and 1990s,^[46] although some suggest that a steady rise in sensitization has been occurring since the 1920s.^[47] The incidence of atopy in developing countries has generally remained much lower.^[46]

Allergic conditions: Statistics and Epidemiology
Allergy type	United States	United Kingdom[48]
Allergic rhinitis	35.9 million[49] (about 11% of the population[50])	3.3 million (about 5.5% of the population[51])
Asthma	10 million suffer from allergic asthma (about 3% of the population). The prevalence of asthma increased 75% from 1980-1994. Asthma prevalence is 39% higher in African Americans than in whites.[52]	5.7 million (about 9.4%). In six and seven year olds asthma increased from 18.4% to 20.9% over five years, during the same time the rate decreased from 31% to 24.7% in 13 to 14 year olds.
Atopic eczema	About 9% of the population. Between 1960 and 1990 prevalence has increased from 3% to 10% in children.[53]	5.8 million (about 1% severe).
Anaphylaxis	At least 40 deaths per year due to insect venom. About 400 deaths due to penicillin anaphylaxis. About 220 cases of anaphylaxis and 3 deaths per year are due to latex allergy.[54] An estimated 150 people die annually from anaphylaxis due to food allergy.[55]	Between 1999 and 2006, 48 deaths occurred in people ranging from five months to 85 years old.
Insect venom	Around 15% of adults have mild, localized allergic reactions. Systemic reactions occur in 3% of adults and less than 1% of children. [56]	Unknown
Drug allergies	Anaphylactic reactions to penicillin cause 400 deaths.	Unknown
Food allergies	Peanut and/or tree nut (e.g. walnut, almond and cashew) allergy affects about three million Americans, or 1.1% of the population.[55]	5-7% of infants and 1-2% of adults. A 117.3% increase in peanut allergies was observed from 2001 to 2005, an estimated 25,700 people in England are affected.
Multiple allergies (Asthma, eczema and allergic rhinitis together)	?	2.3 million (about 3.7%), prevalence has increased by 48.9% between 2001 and 2005.

Although genetic factors fundamentally govern susceptibility to atopic disease, increases in atopy have occurred within too short a time frame to be explained by a genetic change in the population, thus pointing to environmental or lifestyle changes.^[46] Several hypotheses have been identified to explain this increased prevalence; increased exposure to perennial allergens due to housing changes and increasing time spent indoors, and changes in cleanliness or hygiene that have resulted in the decreased activation of a common immune control mechanism, coupled with dietary changes, obesity and decline in physical exercise.^[45] The hygiene hypothesis maintains^[57] that high living standards and hygienic conditions exposes children to fewer infections. It is thought that reduced bacterial and viral infections early in life direct the maturing immune system away from T_H1 type responses, leading to unrestrained T_H2 responses that allow for an increase in allergy.^[58][59]

Changes in rates and types of infection alone however, have been unable to explain the observed increase in allergic disease, and recent evidence has focused attention on the importance of the gastrointestinal microbial environment. Evidence has shown that exposure to food and fecal-oralhepatitis A, Toxoplasma gondii, and Helicobacter pylori (which also tend to be more prevalent in developing countries), can reduce the overall risk of atopy by more than 60%,^[60] and an increased prevalence of parasitic infections has been associated with a decreased prevalence of asthma.^[61] It is speculated that these infections exert their effect by critically altering T_H1/T_H2 regulation.^[62] Important elements of newer hygiene hypotheses also include exposure to endotoxins, exposure to pets and growing up on a farm.^[62] pathogens, such as

Medical specialty

In the United States physicians who hold certification by the American Board of Allergy and Immunology (ABAI) have successfully completed an accredited educational program and an evaluation process, including a secure, proctored examination to demonstrate the knowledge, skills, and experience to the provision of patient care in allergy and immunology.^[63] An allergist-immunologist is a physician specially trained to manage and treat asthma and the other allergic diseases. Becoming an allergist-immunologist requires completion of at least nine years of training. After completing medical school and graduating with a medical degree, a physician will then undergo three years of training in internal medicine (to become an internist) or pediatrics (to become a pediatrician). Once physicians have finished training in one of these specialties, they must pass the exam of either the American Board of Pediatrics (ABP) or the American Board of Internal Medicine (ABIM). Internists or pediatricians who wish to focus on the sub-specialty of allergy-immunology then complete at least an additional two years of study, called a fellowship, in an allergy-immunology training program. Allergist-immunologists who are listed as ABAI-certified have successfully passed the certifying examination of the American Board of Allergy and Immunology (ABAI), following their fellowship.^[64]

In the United Kingdom, allergy is a subspecialty of general medicine or pediatrics. After obtaining postgraduate exams (MRCP or MRCPCH respectively) a doctor works as several years as a specialist registrar before qualifying for the General Medical Council specialist register. Allergy services may also be delivered by immunologists. A 2003 Royal College of Physicians report presented a case for improvement of what were felt to be inadequate allergy services in the UK.^[65]House of Lords convened a subcommittee that reported in 2007. It concluded likewise that allergy services were insufficient to deal with what the Lords referred to as an "allergy epidemic" and its social cost; it made several other recommendations.^[66]

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