Allergies

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Posted by r2d2 03/04/2009 @ 04:14

Tags : allergies, diseases, health

News headlines
Avera Medical Minute: Food Allergy Awareness Week - KSFY
By Nancy Naeve Brown 1 In 25 people in this country have food allergies, not to mention, the epidemic this country is facing due to peanut allergies. Although, the latter has been in the headlines in the last couple of years there are others who face...
Can Honey Solve Your Allergy Problems? - TurnTo23.com
According to the Asthma and Allergy Foundation of America, an estimated 50 million Americans, roughly 1 in 5 are affected by allergies each year. Local doctors know just breathing the air here in Bakersfield is enough to cause irritant inflammation in...
Peanuts banned in part of Campbell's Field - Philadelphia Inquirer
"We are also happy to make special accommodations for patrons with other dietary requirements as well, including kosher diets and gluten allergies." The fans have been making "requests for peanut-free foods - and that includes things cooked with peanut...
Tofutti Brands Ice Cream Sandwiches Recalled; Threat to Consumers ... - Attorney at Law
... sandwiches after samples of the products advertised as being dairy free were found to contain traces of milk contamination, which could be a threat of severe injury to consumers with dairy allergies, according to the Food and Drug Administration....
6 Health Conditions Your Child May Inherit - FOXNews
The odds are about 50-50, the same as for allergies. That makes sense given that eczema is actually a type of allergic reaction. The condition can take parents by surprise, though, especially when neither parent actually has it....
Allergy Med Side Affects Raise Parental Concern - WLKY.com
Singulair is one of the most popular allergy and asthma medications on the market, but the Food and Drug Administration is investigating reports of serious behavioral side effects in children. Those side effects include depression, anxiety,...
Folic Acid May Fight Asthma and Allergies - About - News & Issues
Results revealed that study members with higher folate levels had fewer IgE antibodies—as well as fewer reported allergies, less wheezing, and lower likelihood of asthma. It's possible that folic acid may help decrease allergy and asthma symptoms by...
Sweet Alexis Participating in 12th Annual Food Allergy Awareness Week - PR.com (press release)
Los Osos, CA, May 13, 2009 --(PR.com)-- Michele Fellows, owner and founder of Sweet Alexis- the popular wholesaler and distributor of allergen-free baked goods- is no stranger to the dire consequences associated to food allergies....
Allergy woes: blame global warming - Bartlesville Live
The increase in moisture can be a problem for people with mold allergies, while the dry atmosphere causes pollen and other airborne irritants to circulate longer. They also say new green areas, especially in Alaska, are driving more insects to the area...
Comets finish 10th at Mid-Prairie despite illnesses, allergies - West Liberty Index
Dillon Brooke couldn't complete the final three holes of his round due to allergies that left unable to see out of his left eye. McKillip also was dealing with a bad sinus infection and was sicker than a dog, according to Ingalls, but was able to...

Food allergy

A food allergy is an adverse immune response to a food protein. Food allergy is distinct from other adverse responses to food, such as food intolerance, pharmacologic reactions, and toxin-mediated reactions.

The food protein triggering the allergic response is termed a food allergen. It is estimated that up to 12 million Americans have food allergies, and the prevalence is rising. Six to eight percent of children under the age of three have food allergies and nearly four percent of adults have them. Food allergies cause roughly 30,000 emergency room visits and 100 to 200 deaths per year in the United States. The most common food allergies in adults are shellfish, peanuts, tree nuts, fish, and eggs, and the most common food allergies in children are milk, eggs, peanuts, and tree nuts.

Treatment consists of avoidance diets, in which the allergic person avoids all forms of the food to which they are allergic. For people who are extremely sensitive, this may involve the total avoidance of any exposure with the allergen, including touching or inhaling the problematic food as well as touching any surfaces that may have come into contact with it. Areas of research include anti-IgE antibody (omalizumab, or Xolair) and specific oral tolerance induction (SOTI), which have shown some promise for treatment of certain food allergies. Persons diagnosed with a food allergy may carry an autoinjector of epinephrine such as an EpiPen or Twinject, wear some form of medical alert jewelry, or develop an emergency action plan, in accordance with their doctor.

The reaction may progress to anaphylactic shock: A systemic reaction involving several different bodily systems including hypotension (low blood pressure),loss of consciousness, and possibly death. Allergens most frequently associated with this type of reaction are peanuts, nuts, milk, egg, and seafood, though many food allergens have been reported as triggers for anaphylaxis.

Food allergy is thought to develop more easily in patients with the atopic syndrome, a very common combination of diseases: allergic rhinitis and conjunctivitis, eczema and asthma. The syndrome has a strong inherited component; a family history of allergic diseases can be indicative of the atopic syndrome.

These are often referred to as "the big eight." They account for over 90% of the food allergies in the United States.

The top allergens vary somewhat from country to country but milk, eggs, peanuts, treenuts, fish, shellfish, soy, wheat and sesame tend to be in the top 10 in many countries. Allergies to seeds - especially sesame - seem to be increasing in many countries.

Likelihood of allergy can increase with exposure. For example, rice allergy is more common in East Asia where rice forms a large part of the diet.

In Central Europe, celery allergy is more common. In Japan, allergy to buckwheat flour, used for Soba noodles, is more common.

Red meat allergy is extremely rare in the general population, but a geographic cluster of people allergic to red meat has been observed in Sydney, Australia. There appears to be a possible association between localised reaction to tick bite and the development of red meat allergy.

Fruit allergies exist, such as to apples, pears, jackfruit, etc.

Corn allergy may also be prevalent in many populations, although it may be difficult to recognize in areas such as the United States and Canada where corn derivatives are common in the food supply.

The best method for diagnosing food allergy is to be assessed by an allergist. The allergist will review the patient's history and the symptoms or reactions that have been noted after food ingestion. If the allergist feels the symptoms or reactions are consistent with food allergy, he/she will perform allergy tests.

Generally, introduction of allergens through the digestive tract is thought to induce immune tolerance. In individuals who are predisposed to developing allergies (atopic syndrome), the immune system produces IgE antibodies against protein epitopes on non-pathogenic substances, including dietary components. The IgE molecules are coated onto mast cells, which inhabit the mucosal lining of the digestive tract.

Upon ingesting an allergen, the IgE reacts with its protein epitopes and release (degranulate) a number of chemicals (including histamine), which lead to oedema of the intestinal wall, loss of fluid and altered motility. The product is diarrhea.

Any food allergy has the potential to cause a fatal reaction.

The immune system's Eosinophils, once activated in a histamine reaction, will register any foreign proteins they see. One theory regarding the causes of food allergies focuses on proteins presented in the blood along with vaccines, which are designed to provoke an immune response. Influenza vaccines and the Yellow Fever vaccine are still egg-based, but the Measles-Mumps-Rubella vaccine stopped using eggs in 1994. However large scientific studies do not support this theory, especially as it applies to autoimmune disease.

Another theory focuses on whether an infant's immune system is ready for complex proteins in a new food when it is first introduced.

One hypothesis at this time is the Hygiene hypothesis. While there is no proof for the hygiene hypothesis, people speculate that in modern, industrialized nations, such as the United States, food allergies are more common due to the lack of early exposure to dirt and germs, in part due to the over use of antibiotics and antibiotic cleansers. This hypothesis is based partly on studies showing less allergy in third world countries. Some research suggests that the body, with less dirt and germs to fight off, turns on itself and attacks food proteins as if they were foreign invaders.

Antibiotics have also been implicated in Leaky Gut Syndrome which is another possible cause of food allergies.

A lower incidence of food allergies in the developing world could also be due to differences in diet from the West and less exposure to food allergens.

Others have found that food allergies are due to widespread usage of baby skin care products that contain allergens, such as lotions based upon peanut's oil. These skin care products are cheaper to manufacture than non-allergenic ones and using them sensitizes the baby, which later develops into a food allergy. This theory has yet to come with sufficient explanation as to why occurrence of allergies are on a steady rise in the last two decades.

The mainstay of treatment for food allergy is avoidance of the foods that have been identified as allergens.

If the food is accidentally ingested and a systemic reaction occurs, then epinephrine (best delivered with an autoinjector of epinephrine such as an Epipen or Twinject) should be used. It is possible that a second dose of epinephrine may be required for severe reactions. The patient should also seek medical care immediately.

At this time, there is no cure for food allergies. There are no allergy desensitization or allergy "shots" available for food allergies. Some doctors feel they do not work in food allergies because even minute amounts of the food in question or even food extracts (as in the case of allergy shots) can cause an allergic response in many sufferers.

Ronald van Ree of Amsterdam University expects that vaccines can in theory be created using genetic engineering to cure allergies. If this can be done, food allergies could be eradicated in about ten years.

For reasons that are not entirely understood, the diagnosis of food allergies has apparently become more common in Western nations in recent times. In the United States food allergy affects as many as 5% of infants less than three years of age and 3% to 4% of adults. There is a similar prevalence in Canada.

The most common food allergens include peanuts, milk, eggs, tree nuts, fish, shellfish, soy, and wheat - these foods account for about 90% of all allergic reactions.

Various medical practitioners have a differing views on food allergies. Irritable Bowel Syndrome (IBS) patients have been studied with regards to food allergies. Some studies have reported on the role of food allergy in IBS; only one epidemiological study on functional dyspepsia and food allergy has been published. However, since 2005 several studies have demonstrated strong correlation between IgG and/or IgE food allergy and IBS symptoms The mechanisms by which food activates mucosal immune system are incompletely understood, but food specific IgE and IgG4 appeared to mediate the hypersensitivity reaction in a subgroup of IBS patients. Specific chemicals and receptors have been demonstrated to be critical in food allergy development in murine models. Exclusion diets based on skin prick test, RAST for IgE or IgG4, hypoallergic diet and clinical trials with oral disodium cromoglycate have been conducted, and some success has been reported in a subset of IBS patients.

Studies comparing skin prick testing and ELISA blood testing have found that the results of skin prick testing correlate poorly with symptoms of irritable bowel syndrome that correlate with food allergies demonstrated through ELISA testing and dietary challenge.

Extensive clinical experience has demonstrated significant improvement of patients with IBS whose ELISA-based food allergy testing is positive and where treatment includes a careful exclusion diet.

In addition, many practitioners of alternative medicine ascribe symptoms to food allergy where other doctors do not. The causal relationships between some of these conditions and food allergies have not been studied extensively enough to provide sufficient evidence to become authoritative. The interaction of histamine with the nervous system receptors has been demonstrated, but more study is needed. Other immune response effects are commonly known (swelling, irritation, etc.), but their relationships to some conditions has not been extensively studied. Examples are arthritis, fatigue, headaches, and hyperactivity. Nevertheless, hypoallergenic diets reportedly can be of benefit in these conditions, indicating that the current medical views on food allergy may be too narrow. Holford and Brady (2005) suggest three levels of response; classical immediate-onset allergy (IgE), delayed-onset allergy (giving a positive response on an ELISA IgG test but rarely on an IgE skin prick test), and food intolerance (non-allergic), and claim the last two to be more common. It is important to note that IgG is present in the body and is known to respond to foods. So some medical practitioners, especially allergists, claim that there is no predictive value to these types of tests, despite the studies cited above.

Milk and soy allergies in children can often go undiagnosed for many months, causing much worry for parents and health risks for infants and children. Many infants with milk and soy allergies can show signs of colic, blood in the stool, mucous in the stool, reflux, rashes and other harmful medical conditions. These conditions are often misdiagnosed as viruses or colic.

Some children who are allergic to cow's milk protein also show a cross sensitivity to soy-based products. There are infant formulas in which the milk and soy proteins are degraded so when taken by an infant, their immune system does not recognize the allergen and they can safely consume the product. Hypoallergenic infant formulas can be based on hydrolyzed proteins, which are proteins partially predigested in a less antigenic form. Other formulas, based on free amino acids, are the least antigenic and provide complete nutrition support in severe forms of milk allergy.

About 50% of children with allergies to milk, egg, soy, and wheat will outgrow their allergy by the age of 6. Those that don't, and those that are still allergic by the age of 12 or so, have less than an 8% chance of outgrowing the allergy.

Peanut and tree nut allergies are less likely to be outgrown, although evidence now shows that about 20% of those with peanut allergies and 9% of those with tree nut allergies will outgrow their allergies. In such a case, they need to consume nuts in some regular fashion to maintain the non-allergic status. This should be discussed with a doctor.

Those with other food allergies may or may not outgrow their allergies.

In response to the risk that certain foods pose to those with food allergies, countries have responded by instituting labeling laws that require food products to clearly inform consumers if their products contain major allergens or by-products of major allergens.

Under the Food Allergen Labeling and Consumer Protection Act of 2004 (Public Law 108-282), companies are required to disclose on the label whether the product contains a major food allergen in clear, plain language. The allergens have to clearly be called out in the ingredient statement. Most companies list allergens in a statement separate from the ingredient statement.

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Asthma and Allergy Foundation of America

The Asthma and Allergy Foundation of America (AAFA) is a non-profit organization dedicated to finding a cure for and controlling asthma, food allergies, nasal allergies and other allergic diseases. AAFA's mission is also to educate the public about these diseases. AAFA's motto is "for life without limits" and AAFA represents the 70 million Americans with asthma and allergies.

AAFA was founded in 1953 to address the growing prevalence of asthma and allergic diseases in the United States. AAFA's activities include: (a) funding basic scientific research to help search for cures; (b) conducting public education to promote national awareness of these diseases; and (c) advocating public policies with a goal of improving the quality of life for patients. AAFA has a network of state chapters throughout the United States. AAFA also has a number of local support groups for asthma, food allergies and a variety of other specific allergic conditions.

AAFA is funded by contributions from the public, along with gifts and grants from foundations and government agencies as well as charitable donations from private sector groups. AAFA administers the Asthma & Allergy Friendly Certification Program in the U.S., sponsors Asthma and Allergy Awareness Month each May and also conducts research to identify the Asthma Capitals and the Allergy Capitals (spring and fall rankings), the most challenging places to live in the U.S. with asthma and allergies. AAFA has also developed a variety of asthma and allergy health education programs, that have been validated through formal research to help improve health outcomes for patients.

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Allergy

An allergy testing machine being operated in the diagnostic immunology lab at Lackland Air Force Base

Allergy is a disorder of the immune system often also referred to as 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 inflammatory response. Common allergic reactions include eczema, hives, hay fever, asthma, food allergies, and reactions to the venom of stinging insects such as wasps and bees.

Mild allergies like hay fever are highly prevalent in the human population and cause symptoms such as allergic conjunctivitis, itchiness, and runny nose. Allergies can play a major role in conditions such as asthma. In some people, severe allergies to environmental or dietary allergens or to medication 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 anti-histamines, steroids or other oral medications, immunotherapy to desensitize the response to allergen, and targeted therapy.

The concept of "allergy" was originally introduced in 1906 by the Viennese pediatrician Clemens von Pirquet, after he noted that some of his patients were hypersensitive to normally innocuous entities such as dust, pollen, or certain foods. Pirquet called this phenomenon "allergy" from the Greek words allos meaning "other" and ergon meaning "work". 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. 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.

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.

Many allergens such as dust or pollen are airborne particles. In these cases, symptoms arise in areas in contact with air, such as eyes, nose and lungs. For instance, allergic rhinitis, also known as hay fever, causes irritation of the nose, sneezing, and itching and redness of the eyes. 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.

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, diarrhea, itchy skin, and swelling of the skin during hives. Food allergies rarely cause respiratory (asthmatic) reactions, or rhinitis. Insect stings, antibiotics, and certain medicines produce a systemic allergic response that is also called anaphylaxis; multiple organ systems can be affected, including the digestive system, the respiratory system, and the circulatory system. 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 EpiPen auto-injector. The nature of anaphylaxis is such that the reaction can seem to be subsiding, but may recur throughout a prolonged period of time.

Substances that come into contact with the skin, such as latex, are also common causes of allergic reactions, known as contact dermatitis or eczema. 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.

Risk factors for allergy can be placed in two general categories, namely host and environmental factors. Host factors include heredity, sex, race, and age, with heredity being by far the most significant. However, there have been recent increases in the incidence of allergic disorders that cannot be explained by genetic factors alone. Four major environmental candidates are alterations in exposure to infectious diseases during early childhood, environmental pollution, allergen levels, and dietary changes.

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. Allergic parents are more likely to have allergic children, and their allergies are likely to be more severe than those from non-allergic parents. Some allergies, however, are not consistent along genealogies; parents who are allergic to peanuts may have children who are allergic to ragweed. It seems that the likelihood of developing allergies is inherited and related to an irregularity in the immune system, but the specific allergen is not.

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

According to the hygiene hypothesis, proposed by David P. Strachan, allergic diseases are caused by inappropriate immunological responses to harmless antigens driven by a TH2-mediated immune response. Many bacteria and viruses elicit a TH1-mediated immune response, which down-regulates TH2 responses. The first proposed mechanism of action of the hygiene hypothesis stated that insufficient stimulation of the TH1 arm of the immune system lead to an overactive TH2 arm, which in turn led to allergic disease. In other words, individuals living in too sterile an environment are not exposed to enough pathogens to keep the immune system busy. Since our bodies evolved to deal with a certain level of such pathogens, when it is not exposed to this level the immune system will attack harmless antigens, and thus normally benign microbial objects, like pollen, will trigger an immune response.

The hygiene hypothesis was developed to explain the observation that hay fever and eczema, both allergic diseases, were less common in children from larger families, which were presumably exposed to more infectious agents through their siblings, than in children from families with only one child. The hygiene hypothesis has been extensively investigated by immunologists and epidemiologists and has become an important theoretical framework for the study of allergic disorders. It is used to explain the increase in allergic diseases that has been seen since industrialization, and the higher incidence of allergic diseases in more developed countries. The hygiene hypothesis has now expanded to include exposure to symbiotic bacteria and parasites as important modulators of immune system development, along with infectious agents.

Epidemiological data supports the hygiene hypothesis. Studies have shown that various immunological and autoimmune diseases are much less common in the developing world than the industrialized world and that immigrants to the industrialized world from the developing world increasingly develop immunological disorders in relation to the length of time since arrival in the industrialized world. Longitudinal studies in the third world demonstrate an increase in immunological disorders as a country grows more affluent and, presumably, cleaner. The use of antibiotics in the first year of life has been linked to asthma and other allergic diseases. The use of antibacterial cleaning products has also been associated with higher incidence of asthma, as has birth by Caesarean section rather than vaginal birth.

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.

Exposure to allergens, especially in early life, is an important risk factor for allergy. Alterations in exposure to microorganisms is another plausible explanation, at present, for the increase in atopic allergy. Endotoxin exposure reduces release of inflammatory cytokines such as TNF-α, IFNγ, interleukin-10, and interleukin-12 from white blood cells (leukocytes) that circulate in the blood. 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.

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. 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. 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. In particular, research suggests that allergies may coincide with the delayed establishment of gut flora in infants. However, the research to support this theory is conflicting, with some studies performed in China and Ethiopia showing an increase in allergy in people infected with intestinal worms. Clinical trials have been initiated to test the effectiveness of certain worms in treating some allergies. It may be that the term 'parasite' could turn out to be inappropriate, and in fact a hitherto unsuspected symbiosis is at work. For more information on this topic, see Helminthic therapy.

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.

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 TH2 lymphocyte, which belongs to a subset of T cells that produce a cytokine called interleukin-4 (IL-4). These TH2 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.

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 muscle contraction. This results in rhinorrhea, 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.

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. 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 TH2 cells.

Before a diagnosis of allergic disease can be confirmed, the other possible causes of the presenting symptoms should be carefully considered. Vasomotor rhinitis, for example, is one of many maladies that shares symptoms with allergic rhinitis, underscoring the need for professional differential diagnosis. 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.

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. 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. 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.

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 taken antihistamines sometime the last several days.

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 colormetric immunoassays. 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. 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.

A low total IgE level is not adequate to rule out sensitization to commonly inhaled allergens. 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.

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.

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.

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. 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.

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. Meta-analyses have also confirmed efficacy of the treatment in allergic rhinitis in children and in asthma. 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. 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.

Allergy shot treatment is the closest thing to a ‘cure’ for allergic symptoms. This therapy requires a long-term commitment.

An experimental treatment, enzyme potentiated desensitization (EPD), has been tried for decades but is not generally accepted as effective. 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 approved by the U.S. Food and Drug Administration or of proven effectiveness.

In alternative medicine, a number of allergy treatments are described by its practitioners, particularly naturopathic, herbal medicine, homeopathy, traditional Chinese medicine and applied 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.

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. 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, although some suggest that a steady rise in sensitization has been occurring since the 1920s. The incidence of atopy in developing countries has generally remained much lower.

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. 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. The hygiene hypothesis maintains 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 TH1 type responses, leading to unrestrained TH2 responses that allow for an increase in allergy.

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-oral pathogens, such as hepatitis 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%, and an increased prevalence of parasitic infections has been associated with a decreased prevalence of asthma. It is speculated that these infections exert their effect by critically altering TH1/TH2 regulation. Important elements of newer hygiene hypotheses also include exposure to endotoxins, exposure to pets and growing up on a farm.

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. 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.

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. In 2006, the 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.

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Tree nut allergy

Tree nut allergy is a type of food allergy. It is a hypersensitivity to dietary substances from tree nuts causing an overreaction of the immune system which may lead to severe physical symptoms for millions of people. Nut allergy is slightly different from peanut allergy because the type of nuts that cause the allergic reactions are not the same. Peanuts are considered legumes whereas tree nuts are considered dry fruits. The symptoms of peanut allergy and nut allergy are the same, but a person with peanut allergies may not necessarily also be allergic to tree nuts, and vice versa.

Tree nut allergies occur mainly, but not exclusively, in children. They are usually treated with an exclusion diet and vigilant avoidance of foods that may be contaminated with tree nuts or nut particles and/or oils. The most severe nut allergy reaction is called anaphylaxis and is an emergency situation requiring immediate attention and treatment with epinephrine.

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Seafood allergy

Seafood allergy is a type of food allergy. It is a hypersensitivity to dietary substances from shellfish, scaly fish, or crustaceans, causing an overreaction of the immune system which may lead to severe physical symptoms for millions of people. The Asthma and Allergy Foundation of America estimates that the majority of pediatric and adult food allergy patients have a seafood allergy. It occurs mainly, but not exclusively, in adults. It is usually treated with an exclusion diet and vigilant avoidance of foods that may be contaminated with shellfish or fish ingredients and/or oils. The most severe seafood allergy reaction is called anaphylaxis and is an emergency requiring immediate attention and treatment with Epinephrine, which is administered with the EpiPen. For prevention when an attack is evident but not at the fatal stage use benadryl quick dissolve which can dampen the effects and symptoms of a fish allergy.

Fish allergies can be conducted through the air when it is being cooked or when people around you are eating fish.

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Monster Allergy

Monster Allergy is a comic book series of Disney Italy published by Buena Vista Comics.

In 1996, Disney Italy launched a new comic company called PKNA (Paperinik New Adventures) with an unusual format, featuring human characters rather than the typical anthropomorphic animals that Walt Disney used the first thirty years. This format convinced the Milan division of Disney to launch new plans. The comic book series of Monster Allergy was published on October 13, 2003, and is therefore third of these series, which includes Atlantis: The Lost Empire and W.I.T.C.H. It is published by Buena Vista Comics. The comic books were created by Alessandro Barbucci, Katja Centomo, Francesco Artibani and Barbara Canepa of Sky Doll and W.I.T.C.H.. The series lasted 29 issues; however, it is still in the course of reprints, in newspaper stands the 13th of every month.

Monster Allergy details the adventures of Elena Potato, who moves with her family to Old Mill Village, and Ezekiel Zick, whose father is missing and is affected by all sorts of allergies including one that allows him to see monsters. Together, they uncover the secrets of the world of monsters. Zick and Elena face terrible danger and lethal enemies, which they are usually able to overcome. They are aided by Timothy-Moth, Zick's "cat", who is found to be unusual in that he has his own powers and can speak; he turns out to be a Tutor and a guardian of the monsters that are detained and tutored for breaking the rules of their monster city, Bibbur-Si.

Monster Tamers pass the natural power of the Tone from father to son, thus creating long dynasties of heroes. Tamers are able to spot monsters and Tame them. If they won't be subjugated, they are captured and imprisoned in a special container, called a Taming box or Dom Box. This container is specially treated in order to preserve the prisoner while preventing his escape. Every type of monster needs its own special Dom Box and Canning method. Most importantly, a Tamer must master the Tone, which is an enormous power but is strictly linked to the skills of who wields it.

In the Comic book and Animated series, centuries ago, Tamers and Tutors were friends and allies, and they protected Bibbur-Si together. In time, some of the Tamers started to abuse their powers, and betrayed the Tutors' trust. Because of this, the Maximum Tutors exiled all the Tamers, including the noble Zick clan, sending them to Detention Oases, under supervision of the Tutors and Stellar Tutors.

In the animated series, Tamers are humans with special powers to fight evil monsters and dark phantoms, while in the comic book series, Tamers aren't humans but monsters that are "by chance or by design, look exactly like" humans with special powers but with same motives, which was explained in the twelfth issue of the comics.

A Tamer, in order to be known as such, must possess the power of the Dom (or "Tone"), a natural energy that can subjugate Monsters and Phantoms. However, this talent is not just limited to Taming. If it developed correctly it can unleash unexpected powers in its bearer: The hand gesture strengthens the Tamer's orders and allows him to move, see and command monsters, go through walls, breath under water or Tame telepathically. In the Comic Book Series, the Dom is weakened by the scent of lavender, and if a Tamer's voice cannot be heard, his powers will not work.

Monster Keepers are humans who can see monsters, and allow them to live in their homes, in Detention Oases. They help the Tutors defend the monsters from the dangers of the human world as well as the monster world. The gift of Sight is passed from parent to child, and few special people, so that entire generations of Keepers can look after the Oasis in total secret. Some Keepers marry Tamers to continue their generations, and children become either Tamers or Keepers.

In the Philippines, Singapore, Malaysia and other countries, Monster Allergy was published as a comic magazine last September 2004. However, Summit Media (the publisher of Monster Allergy in the Philippines) stopped publishing Monster Allergy at Issue 14. In Malaysia, it stopped publishing it at the 27th issue. Chuang Yi Singapore finished publishing it until the 29th issue, the last of the comic book series. The comic book titles are quite different from the television series titles. Every issue contains a 44-page Monster Allergy story.

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Source : Wikipedia