Exposure to environmental allergens is the most extensively studied potential risk factor for sensitization and manifestation of atopy and asthma. From a number of cross-sectional studies performed in children and adults, it has become obvious that there is a close association between allergen exposure, particularly in the domestic environment, and sensitization to that specific allergen. Longitudinal studies such as the MAS (Multicenter Allergy Study) study in Germany have clearly demonstrated that during the first years of life there is a dose–response relationship between indoor allergen exposure to dust mite and cat allergens and the risk of
sensitization to cat and mites, respectively.
As far as the manifestation of atopic dermatitis and asthma are concerned, the situation is much less clear. Early studies performed by Sporik suggested that exposure of sensitized children to dust mite allergens determines not only the risk of asthma but also the time of the onset of the disease. More recent investigations by the same group, however, suggest that other factors besides allergen exposure are important in determining which children develop asthma.
In a comprehensive meta-analysis, evaluated several environmental factors said to be responsible for the incidence and severity of atopic diseases, particularly asthma. After comparing the strengths of the various effects, she concluded that on the basis of the literature, indoor allergen exposure is the environmental component with by far the strongest impact on the manifestation of asthma. In recent years, however, the paradigm that exposure induces asthma with airway inflammation via sensitization has been challenged. In several countries, the prevalence of asthma in children has been increasing independent of allergen exposure.
Data sets obtained from the MAS birth cohort suggest that while domestic allergen exposure is a strong determinant for early sensitization in childhood, it cannot be The Allergy Epidemic: A Look into the Future considered as a primary cause of airway hyper-responsiveness or asthmatic symptoms, since during the first 3 years of life the manifestation of wheeze is not related to elevated serum IgE levels or specific sensitization. Studies following up birth cohorts to adolescence have recently indicated that 90% of children with wheeze but without atopy lose their symptoms at school age and retain normal lung function in puberty. By contrast, sensitization to perennial allergens (house dust mites, cats, and dogs) developing in the first 3 years of life was associated with a loss of lung function at school age. Concomitant exposure to high levels of perennial allergens early in life aggravates this process. Such exposure also enhances the development of airway hyper-responsiveness in sensitized children with wheeze.
From these data, it can be concluded that impairment of lung function during school age is determined by continuing allergic airway inflammation beginning in the first 3 years of life.
A number of intervention studies to examine the effects of indoor allergen elimination on the incidence of asthma are currently being performed in cohorts followed prospectively from birth. The results will have a strong impact on public health policies because they will determine whether considering indoor allergen elimination as an important element of primary prevention of various atopic manifestations is meaningful. Even if the result is that other factors play major parts in determining whether an atopic child will develop asthma, so that allergen elimination as a measure of primary prevention is inefficient, reduction of allergen exposure will still remain as a very important element in secondary prevention.
Feb 23, 2012
Feb 21, 2012
The Atopic March
The term “atopic march” refers to the natural history of atopic manifestations, characterized
by the typical sequences of immunoglobulin E (IgE) antibody responses and clinical symptoms that appear during a certain age period, persist over years and decades, and often show a tendency for spontaneous remission with time.
Prospective cohort studies have shown that sensitization to food allergens occurs usually during the first months of life with the antibody response to cow’s milk and hen’s egg occurring most frequently. Sensitization against inhalant allergens usually develops after the first 2 years of life. Most of these children will develop IgE responses to a wide array of environmental allergens such as house dust mites, animal dander, and pollen.
Specific patterns of atopic sensitization are associated with certain atopic illnesses. Atopic eczema is primarily related to IgE responses to dietary allergen, while individuals with allergic rhinitis tend to become sensitized to seasonal outdoor allergens. Specific IgE responses in asthmatic children are usually directed against perennial and indoor allergen such as house dust mites. Several studies have shown that early sensitization during infancy is a predictor for the persistence of childhood asthma until adolescence.
In the German Multicenter Allergy Study, food sensitization before age 1 to 2 years with or without concurrent inhalant sensitization was a strong predictor for the development of asthma and airway hyper-responsiveness until school age.
Our understanding of the determinants of the natural history of allergic diseases is limited. Although a strong genetic basis for atopy and asthma has been described and several genes have been identified, which are associated with different phenotypes, a variety of modifiable environmental and lifestyle factors have been discovered in the past, which might offer future options for primary prevention.
by the typical sequences of immunoglobulin E (IgE) antibody responses and clinical symptoms that appear during a certain age period, persist over years and decades, and often show a tendency for spontaneous remission with time.
Prospective cohort studies have shown that sensitization to food allergens occurs usually during the first months of life with the antibody response to cow’s milk and hen’s egg occurring most frequently. Sensitization against inhalant allergens usually develops after the first 2 years of life. Most of these children will develop IgE responses to a wide array of environmental allergens such as house dust mites, animal dander, and pollen.
Specific patterns of atopic sensitization are associated with certain atopic illnesses. Atopic eczema is primarily related to IgE responses to dietary allergen, while individuals with allergic rhinitis tend to become sensitized to seasonal outdoor allergens. Specific IgE responses in asthmatic children are usually directed against perennial and indoor allergen such as house dust mites. Several studies have shown that early sensitization during infancy is a predictor for the persistence of childhood asthma until adolescence.
In the German Multicenter Allergy Study, food sensitization before age 1 to 2 years with or without concurrent inhalant sensitization was a strong predictor for the development of asthma and airway hyper-responsiveness until school age.
Our understanding of the determinants of the natural history of allergic diseases is limited. Although a strong genetic basis for atopy and asthma has been described and several genes have been identified, which are associated with different phenotypes, a variety of modifiable environmental and lifestyle factors have been discovered in the past, which might offer future options for primary prevention.
Feb 13, 2012
How Do Steroids Treat Allergies?
Many people in the U.S. suffers from hay fever. Steroid medications don't just make life easier; they are lifesaving and are normally prescribed to be used as needed.
Sterois are also prescribed after a life-threatening health scare, such as an anaphylactic reaction.
There are several types of steroid medications, including but not limited to Prednisone, Nasacort, Nasonex, Flonase, AeroBid, Pulmicort and Beclovent.
Food and environmental allergies are both immune system responses, one to food and the other to pollens, dust and mold spores. Steroid medications suppress the immune system response, therefore minimizing inflammation, pain and discomfort.
Side effects of anabolic steroids can include weight gain, fluid retention, mood swings, increased risk of infection, suppressed adrenal gland hormone production and increased blood pressure. It is highly recommended that people on corticosteroids stay away from those with contagious infections.
Sterois are also prescribed after a life-threatening health scare, such as an anaphylactic reaction.
There are several types of steroid medications, including but not limited to Prednisone, Nasacort, Nasonex, Flonase, AeroBid, Pulmicort and Beclovent.
Food and environmental allergies are both immune system responses, one to food and the other to pollens, dust and mold spores. Steroid medications suppress the immune system response, therefore minimizing inflammation, pain and discomfort.
Side effects of anabolic steroids can include weight gain, fluid retention, mood swings, increased risk of infection, suppressed adrenal gland hormone production and increased blood pressure. It is highly recommended that people on corticosteroids stay away from those with contagious infections.
Feb 2, 2012
The Allergy Epidemic: A Look into the Future
U. Wahn
Over the past decades, the increasing rates of allergic conditions among affluent societies have posed a heavy burden on healthcare systems. Cross-sectional studies such as the International Study of Asthma and Allergies in Childhood (ISAAC) have confirmed that atopic diseases such as atopic dermatitis, asthma, and seasonal allergic rhinoconjunctivitis represent major health problems in many countries, particularly in childhood.
During the past 2 decades, two general hypotheses have been proposed in the literature in connection with the observed increases of atopy and asthma in childhood:
- New risk factors that were not known several decades ago might have become relevant in connection with nutrition, environmental exposure, and lifestyle. Protective factors related to a more traditional lifestyles common in the past might have been lost, which could have led to increased susceptibility to atopic diseases.
Over the past decades, the increasing rates of allergic conditions among affluent societies have posed a heavy burden on healthcare systems. Cross-sectional studies such as the International Study of Asthma and Allergies in Childhood (ISAAC) have confirmed that atopic diseases such as atopic dermatitis, asthma, and seasonal allergic rhinoconjunctivitis represent major health problems in many countries, particularly in childhood.
During the past 2 decades, two general hypotheses have been proposed in the literature in connection with the observed increases of atopy and asthma in childhood:
- New risk factors that were not known several decades ago might have become relevant in connection with nutrition, environmental exposure, and lifestyle. Protective factors related to a more traditional lifestyles common in the past might have been lost, which could have led to increased susceptibility to atopic diseases.
Allergic diseases are increasing in prevalence worldwide
Allergic diseases are increasing in prevalence worldwide, in industrialized as well as industrializing countries, affecting from 10%–50% of the global population with a marked impact on the quality of life of patients and with substantial costs. Thus, allergy can be rightfully considered an epidemic of the twenty-first century, a global public health problem, and a socioeconomic burden. With the projected increase in the world’s population, especially in the rapidly growing economies, it is predicted to worsen as this century moves forward.
Allergies are also becoming more complex. Patients frequently have multiple allergic disorders that involve multiple allergens and a combination of organs through which allergic diseases manifest. Thus exposure to aeroallergens or ingested allergens frequently gives rise to a combination of upper and lower airways disease, whereas direct contact or ingestion leads to atopic dermatitis with or without food allergy.
Food allergy, allergic drug responses and anaphylaxis are often severe and can be life-threatening. However, even the less severe allergic diseases can have a major adverse effect on the health of hundreds of millions of patients and diminish quality of life and work productivity. The need of the hour to combat these issues is to promote a better understanding of the science of allergy and clinical immunology through research, training and dissemination of information and evidence-based better practice parameters.
Allergies are also becoming more complex. Patients frequently have multiple allergic disorders that involve multiple allergens and a combination of organs through which allergic diseases manifest. Thus exposure to aeroallergens or ingested allergens frequently gives rise to a combination of upper and lower airways disease, whereas direct contact or ingestion leads to atopic dermatitis with or without food allergy.
Food allergy, allergic drug responses and anaphylaxis are often severe and can be life-threatening. However, even the less severe allergic diseases can have a major adverse effect on the health of hundreds of millions of patients and diminish quality of life and work productivity. The need of the hour to combat these issues is to promote a better understanding of the science of allergy and clinical immunology through research, training and dissemination of information and evidence-based better practice parameters.
Dec 7, 2011
Facts About Allegra & Fruit Juice
When you take a medication orally, it ends up in your digestive tract, where it starts to do its work. All medicines must somehow make their way into your bloodstream, which carries them where they need to go to have an effect.
Allegra was designed to target tiny receptors on cells in your small intestines. These receptors absorb the Allegra and help it work where it needs to. Unfortunately, certain fruit juices, especially orange and grapefruit juice, interfere with this absorption.
Studies have shown that absorption can be reduced by as much as 40%. And that means, you're not really getting your full dose of Allegra! So, obviously, it's not going to work as well as you'd expect either.
Antacids have a similar "blocking" effect on the receptors.
Allegra
Allegra, or fenofexadine in generic form, is a second-generation antihistamine that just became available over-the-counter early in 2011. It happens to be my antihistamine of choice, and for many other allergy sufferers as well. It doesn't make you drowsy, and when taken as directed, it can provide extraordinarily effective control over bothersome allergy symptoms.
I've taken Allegra off an on for years (couldn't always get it when it was still a prescription medication). But I have to admit, I just recently learned of the problem with its effectiveness when taken with fruit juice.
Nov 23, 2011
Contact allergies can protect against a small number of cancers
Contact allergies can protect against a small number of cancers, Danish researchers write.
Men and women was found inverse association between contact allergy and non-melanoma skin cancer, and breast cancer. Women with a contact allergy was found to reverse the trend of brain cancer.
However, the authors have also identified positive associations between contact allergy and bladder cancer.
Inverse associations support the theory of immunological surveillance, in which allergic symptoms - a negative impact hyperimmune, according to a report published in the online edition of «BMJ Open» on July 11.
The reason for these associations remains unclear, and they are not necessarily the result of a causal relationship. "Our study - the research, and it is difficult to make recommendations directly to clinicians based on a single study," - said Dr. Kaare Engkild (National Allergy Research Center, Copenhagen, Denmark).
"I would not recommend the reduction of screening for breast cancer, non-melanoma skin cancer, or cancer of the brain, although the emergence of such associations should lead to further research", - said Dr. Engkild.
Using the registration data, Dr. Engkild and colleagues identified 16 922 patients with dermatitis who underwent tests for contact allergy from November 1984 to December 2008. Of this group, 6065 (35.8%) tested positive for at least 1 allergen, at least in one case. The authors note that the prevalence of contact allergy was higher in women than in men (41.4% vs. 26.1%).
The data were linked with the Danish Cancer Registry, and 3200 patients (18.9%) with dermatitis has been identified as having a benign tumor and / or malignant cancer diagnosis, 1207 (37.7%) of them also had positive test results for contact allergy .
Approximate analysis of the data showed "a confident and significant association" between contact allergy and the presence in the Register of Cancer (odds ratio 1.1). Odds ratios for different groups of cancer were calculated using logistic regression analysis, after adjusting for age and sex.
Breast cancer (odds ratio 0.80) and non-melanoma skin cancer (odds ratio 0.83) in both sexes, were found to inversely and significantly associated with contact allergy. Bladder cancer is positively and significantly associated with contact allergy (odds ratio 1.44).
The authors also studied the interaction between the different subtypes of cancer and sex, and only found a link to brain cancer / central nervous system. Following a standardized regression in women with dermatitis between brain cancer / central nervous system and contact allergy to reverse the trend of association (odds ratio 0.36).
Further studies, standardized by environmental factors such as smoking and socio-economic background needed to understand the role of contact allergy in the development of cancer, the scientists conclude.
Men and women was found inverse association between contact allergy and non-melanoma skin cancer, and breast cancer. Women with a contact allergy was found to reverse the trend of brain cancer.
However, the authors have also identified positive associations between contact allergy and bladder cancer.
Inverse associations support the theory of immunological surveillance, in which allergic symptoms - a negative impact hyperimmune, according to a report published in the online edition of «BMJ Open» on July 11.
The reason for these associations remains unclear, and they are not necessarily the result of a causal relationship. "Our study - the research, and it is difficult to make recommendations directly to clinicians based on a single study," - said Dr. Kaare Engkild (National Allergy Research Center, Copenhagen, Denmark).
"I would not recommend the reduction of screening for breast cancer, non-melanoma skin cancer, or cancer of the brain, although the emergence of such associations should lead to further research", - said Dr. Engkild.
Using the registration data, Dr. Engkild and colleagues identified 16 922 patients with dermatitis who underwent tests for contact allergy from November 1984 to December 2008. Of this group, 6065 (35.8%) tested positive for at least 1 allergen, at least in one case. The authors note that the prevalence of contact allergy was higher in women than in men (41.4% vs. 26.1%).
The data were linked with the Danish Cancer Registry, and 3200 patients (18.9%) with dermatitis has been identified as having a benign tumor and / or malignant cancer diagnosis, 1207 (37.7%) of them also had positive test results for contact allergy .
Approximate analysis of the data showed "a confident and significant association" between contact allergy and the presence in the Register of Cancer (odds ratio 1.1). Odds ratios for different groups of cancer were calculated using logistic regression analysis, after adjusting for age and sex.
Breast cancer (odds ratio 0.80) and non-melanoma skin cancer (odds ratio 0.83) in both sexes, were found to inversely and significantly associated with contact allergy. Bladder cancer is positively and significantly associated with contact allergy (odds ratio 1.44).
The authors also studied the interaction between the different subtypes of cancer and sex, and only found a link to brain cancer / central nervous system. Following a standardized regression in women with dermatitis between brain cancer / central nervous system and contact allergy to reverse the trend of association (odds ratio 0.36).
Further studies, standardized by environmental factors such as smoking and socio-economic background needed to understand the role of contact allergy in the development of cancer, the scientists conclude.
Intestinal bacterium Helicobacter pylori protects the body from allergic asthma
At the conclusion of Immunology of the University of Zurich, an intestinal bacterium Helicobacter pylori protects the body from allergic asthma.
In a joint study with the University of Mainz allergists of Johann Gutenberg (University Medical Center of the Johannes Gutenberg University Mainz) found a strong case to support the hypothesis that the incidence of allergic diseases in developed countries is associated with the rapid disappearance of certain microorganisms, which in most cases asymptomatic organisms live in each of the second person on the planet.
Almost an epidemic prevalence of allergic asthma in recent decades due to traditionally pollution, smoking, hygiene hypothesis, and the widespread use of antibiotics. According to the hygiene hypothesis, reduced exposure to bacterial antigens in early childhood and lack of immune stress leads to increased risk of developing allergies and autoimmune diseases.
Researchers have shown that the increase in asthma cases may be due to the disappearance of gastric bacteria Helicobacter pylori in developed societies of the West. These bacteria can survive in the acidic environment of the stomach. Most Helicobacter pylori strains not pathogenic to humans and their small concentration does not lead to diseases of the gastrointestinal tract.
However, in certain circumstances, in particular, the weakening of the immune system, infection can cause gastritis, gastric ulcer, duodenal ulcer and gastric cancer. Therefore, doctors often prescribe prophylactic antibiotics, which destroy Helicobacter pylori, even those patients who have no complaints.
During the experiment it was shown that Helicobacter pylori infection early in life protects against asthma. In the experimental mice infected with the bacteria in a few days after birth, there was a immunulogic tolerance to Helicobacter pylori and the almost total lack of response to allergens that cause asthma. Animals that are at an early age have not been infected with Helicobacter pylori, were exposed to an allergy to a much greater extent.
In a joint study with the University of Mainz allergists of Johann Gutenberg (University Medical Center of the Johannes Gutenberg University Mainz) found a strong case to support the hypothesis that the incidence of allergic diseases in developed countries is associated with the rapid disappearance of certain microorganisms, which in most cases asymptomatic organisms live in each of the second person on the planet.
Almost an epidemic prevalence of allergic asthma in recent decades due to traditionally pollution, smoking, hygiene hypothesis, and the widespread use of antibiotics. According to the hygiene hypothesis, reduced exposure to bacterial antigens in early childhood and lack of immune stress leads to increased risk of developing allergies and autoimmune diseases.
Researchers have shown that the increase in asthma cases may be due to the disappearance of gastric bacteria Helicobacter pylori in developed societies of the West. These bacteria can survive in the acidic environment of the stomach. Most Helicobacter pylori strains not pathogenic to humans and their small concentration does not lead to diseases of the gastrointestinal tract.
However, in certain circumstances, in particular, the weakening of the immune system, infection can cause gastritis, gastric ulcer, duodenal ulcer and gastric cancer. Therefore, doctors often prescribe prophylactic antibiotics, which destroy Helicobacter pylori, even those patients who have no complaints.
During the experiment it was shown that Helicobacter pylori infection early in life protects against asthma. In the experimental mice infected with the bacteria in a few days after birth, there was a immunulogic tolerance to Helicobacter pylori and the almost total lack of response to allergens that cause asthma. Animals that are at an early age have not been infected with Helicobacter pylori, were exposed to an allergy to a much greater extent.
Nov 21, 2011
Avian Flu in Egypt
November 2, 2011 Ministry of Health of Egypt has informed World Health Organization of the case of human infection with avian influenza A (H5N1).
September 17 at the year-old boy developed symptoms. September 21 he was hospitalized. The child was treated, recovered and 25 September he was discharged from the hospital.
Investigations into the source of infection showed that the boy had contact with poultry is contained near his home.
The case was confirmed by the Central Public Health Laboratories and the Egyptian National Influenza Center under the WHO Global Influenza Surveillance.
Of the 152 cases confirmed to date in Egypt, 52 have been fatal.
September 17 at the year-old boy developed symptoms. September 21 he was hospitalized. The child was treated, recovered and 25 September he was discharged from the hospital.
Investigations into the source of infection showed that the boy had contact with poultry is contained near his home.
The case was confirmed by the Central Public Health Laboratories and the Egyptian National Influenza Center under the WHO Global Influenza Surveillance.
Of the 152 cases confirmed to date in Egypt, 52 have been fatal.
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