Talk:Allergy

Allergic march

I suggest that the term "allergic march" be discussed or at least mentioned. Thomas.Hedden (talk) 16:58, 10 April 2009 (UTC)

Sources: atopic dermatitis to asthma: the atopic march.; atopic march: what's the evidence?; for primary prevention of atopy in children. Rknight (talk) 05:19, 15 April 2011 (UTC)

kip — Preceding unsigned comment added by 80.127.127.47 (talk) 13:26, 30 June 2011 (UTC)

Atopy Merger proposal

I think we should merge in the Atopy article to this Allergy article. The lead of the allergy article identifies Atopy as another name by which Allergy is known. The Atopy article explains the meaning of the term to be "an allergic hypersensitivity affecting parts of the body not in direct contact with the allergen". This appears to be a type of allergic reaction and therefore I think the content would be better developed and integrated in the Allergy article. Alan.ca (talk) 13:01, 6 May 2009 (UTC)

I agree that the current content of the Atopy article could be merged with allergy. On the other hand, the atopy article should be re-written as it is rather inacurate. Atopy is something along the lines of "a propensity to respond to inocuous antigens with an IgE antibody response". So what I'm saying is that the atopy article should be re-written and the merger problem should disapear. PieCam (talk) 04:26, 14 December 2009 (UTC)

I don't think the article should be merged. Medical students routinely use Wikipedia to reference information presented in class/texts, and when I just searched for "atopy" the wiki that came up was exactly the information I was looking for; if the article were merged with "allergy" that specific information would have been much harder to locate. Elisabeth.netherton (talk) 02:17, 16 February 2010 (UTC)

Atopy, while related to hypersensitivity/allergy, is a separate clinical entity that merits an independent write-up. I agree with Elizabeth. —Preceding unsigned comment added by Thewildtype (talk • contribs) 23:39, 20 February 2010 (UTC)

I do not think Atopy should be merged with Allergies. Atopic syndrome involves a special combination of symptoms and predispositions. Allergies is a very broad category.

I agree that atopy should be separate. However, I'd prefer to see discussion of other disorders than Eczema. Pkeets (talk) 02:24, 25 August 2010 (UTC)

It is similar but seperate. Doc James (talk · contribs · email) 13:09, 19 October 2011 (UTC)

Idea for new section / paragraph / sentence

A list of all the classes of biomolecule that can provoke an allergic response would be good - I can't provide it because I'm not a specialist in this area. Notreallydavid (talk) 01:58, 22 July 2010 (UTC)

I think we'd run out of petabytes, first. Rknight (talk) 05:33, 15 April 2011 (UTC)

As someone who came searching for Atopy, Atopic Triad and Atopic Syndrome seeking information outside of the normal articles on Allergies, I urge you not to combine or merge this topic. And it certainly should not be merged under Eczema or Dermatitis as that is only one factor or aspect of Atopy. It was immensely helpful for me to find this article outside of those other topics. —Preceding unsigned comment added by 75.130.179.43 (talk) 15:01, 19 May 2011 (UTC)

Delete protein sections?

I recommend deletion of 'Protein structure and organization', 'Protein function', and 'Proteins and the immune system'. First two are good summaries, but do not contain any information that is specific to discussion of the immune system. Their work would be done better by links. 'Proteins and the immune system' is uninformative - needs to be developed or excised. Notreallydavid (talk) 02:06, 22 July 2010 (UTC)

Global Significance

This article doesn't give a universal view, it seems to just concentrate on UK and USA. You can't show how allergies affect the Western world without showing the rest of the world. —Preceding unsigned comment added by 89.242.146.9 (talk) 14:16, 10 August 2010 (UTC)

Culture, politics, geography, etc. are entirely irrelevant. Allergies affect all people exactly the same way - we are all the same species. Roger (talk) 23:49, 15 December 2010 (UTC)

Even though the manifestation of allergy is the same regardless of the ethnicity of a person, the prevalence of allergies is still variable across the world. 109.246.249.88 (talk) 12:47, 22 May 2011 (UTC)

Maybe it's the uneven distribution of allergens (and co-factors such as chemical pollution levels), not allegies per se, that lies behind the difference in distribution of allergy. Roger (talk) 16:21, 22 May 2011 (UTC)

new work about origin of alergy

There is new work, about genetic basis of alergies such as eczema an ashthma. http://www.the-scientist.com/article/display/57833/ It suggests increase of mutation in some important genes and interaction with othere genes, which leads to alergies. If anybody with better knowledge could read this and maybe use this to improve article, it would be awsome. —Preceding unsigned comment added by 91.213.255.7 (talk) 05:51, 4 December 2010 (UTC)

Proper "medical/scientific" sources.

So there has been some to-and-fro deleting and undeleting with the deletionists demanding "proper scientific peer reviewed" sources for the contentious paragraph. So I set about doing the incredibly difficult task of digging through thousands of libraries stuffed to the rafters with umpteen zillion mouldy old journals (actually it was more like 30 seconds on Google) and provided a reference to the exact original "proper scientific peer reviewed" journal article that is the subject of the paragraph. But an editor (who I have noticed has IMHO a tendency to "ownership" behaviour in medical articles) rejected the source I provided (even though it is the exact original article) and deleted the paragraph yet again! Anyway this is just to let y'all know that y'all can stuff this article up your collective nether oroficii - I don't give a fuck any more. Roger (talk) 20:30, 19 December 2010 (UTC)

Hygiene hypothesis

It seemed odd to me that there is no reference to the seminal paper by Strachan (1989) in the section for the "Hygiene hypothesis". Instead, the paper is only cited under the "Epidemiology" section, while the hygiene hypothesis section sites someone's blog (which in turn refers to Strachan's work). This doesn't seem right. — Preceding unsigned comment added by Buzwad (talk • contribs) 21:00, 2 August 2011 (UTC)

Moved

This is based on primary research. We need to use review articles.

===Virulent Pathogens and Allergy=== Much of the initial focus on candidate infections that contribute to lowered atopy was concentrated on non-specific infections and yielded mixed results. Early studies showed that children who had more than one non-wheezing lower respiratory tract infection during the first 3 years of life had lower serum IgE and fewer, milder reactions to skin prick test allergens. However, further research has yielded conflicting results. Other studies have also shown that children who attended daycare during the first year of life had a lower prevalence of atopyand asthma. However, a Norwegian study concluded the opposite and actually showed that daycare attendance was associated with an increased risk of asthma in children. Furthermore, other more specific studies have showed an association between RSV infection in early life and an increased risk for asthma. One of the first studies to investigate the influence of specific pathogens on atopy was carried out in Guinea-Bissau. This study showed a lower prevalence of atopy in 133 adults who were infected with measles during their childhood. However, a subsequent study in Finland found an opposite correlation. Another study conducted by Italian scientists showed a decreased level of atopy in participants who had Hepatitis A, T gondii, and H pylori. The same study, however, failed to show any statistically significant correlation between atopy and Measles, Mumps, Rubella, Chickenpox, CMV, and HSV-1. A study conducted in the USA found an inverse correlation between seropositivity for HAV, T gondii, and HSV-1 and allergic rhinitis. The same study found a similar correlation between HAV and HSV-1 and asthma. However, no such a correlation between HSV-2, hepatitis B, and hepatitis C was found. More consistent, but by no mean perfect, results seem to come from studies where a combination of pathogens is investigated. A Danish study showed that seropositivity to 2 or 3 markers of poor hygiene was correlated with a lower prevalence of atopy and allergic rhinitis. These markers included HAV, H pylori, and T gondii. Furthermore, the study showed a decreasing level of atopy with an increasing index of exposure to the aforementioned pathogens. Individuals simultaneously seropositive for HAV, T gondii, and HSV-1 were found to have four times lower odds of having allergic rhinitis and 2 times lower odds of having asthma than participants seronegative for all three pathogens. A study carried out in 3 independent centers in Iceland, Estonia, and Sweden also found an inverse relationship between atopy and HAV, H pylori, and T gondii. This same study, however, failed to show that HAV alone was associated with lower atopy. Moreover, a Finish study, conducted on both sides of the border between Russia and Finland, found that inhabitants on the Russian side of the border had a markedly lower prevalence of atopy. Statistical analyses showed that most of this disparity could be explained by the difference in seropositivity to H pylori, with higher seropositivity being associated with lower atopy. Factoring in the influence of A actinomycetemcomitans, HSV and C pneumonia further explains the difference in atopy in a stepwise fashion. The chronic nature of H pylori can be one of major factors in its ability to exhibit immunomodulatory effects and lower atopy. Data shows that H pylori is, in fact, able to induce regulatory T-cell production. This fits in with its chronic nature, as chronic diseases characteristically produce IL-10, a necessary differentiation factor in the development of inducible regulatory T-cells. H pylori has been part of our natural gut flora for millions of years, but is gradually being eliminated, and therefore the Finnish study may be suggestive of its role in the hygiene hypothesis. Seropositivity for pathogens like HAV, H pylori, and T gondii are considered to be markers of an unhygienic lifestyle. This lifestyle includes the consumption of foods, which were naturally prepared and lack preservatives and pasteurization. Fecal-oral pathogens are not the only factors shown to be able to lower the level of atopy. The aforementioned study carried out in Iceland, Estonia, and Sweden also showed that seropositivity for HSV-1, EBV, C pneumonia, and CMV was associated with decreased atopy. In fact, they showed that seropositive individuals for 3 or more of these air pathogens did not differ from seropositive individuals for all 3 of the studied oral fecal pathogens. The Italian study showed a conflicting result for the relationship of airborne pathogens and atopy. This study showed that the combined effect of measles, mumps, rubella, chickenpox, CMV, and HSV-1 increased the risk of atopy. However, it is important to note that the characteristics of these diseases can be said to be that of highly-infectious pathogens, while those investigated in Iceland, Estonia, and Sweden were reparatory pathogens related to close contact and over-crowding. As over-crowding and poor hygiene often go hand in hand, it may be argued that those diseases associated with poor hygiene, overcrowding ,and poverty tend to be more closely associated with atopic reduction than highly contagious acute infections.

Gut Bacteria, Probiotics, and Allergy

An area of focus in research on the hygiene hypothesis is on the influence of natural gut flora on the development of atopy. At birth, a newborn's gastrointestinal tract is sterile and the development of GALT is in its initial stages. Commensal gut flora make up the majority of stimulus necessary for normal GALT development. A number of studies have shown that the absence of this constant stimulus results in a decreased intestinal surface area, altered enzyme patterns, an increased intestinal permeability, a defective IgA immune response, and a deficient oral tolerance. In order to develop oral tolerance, ingested antigenic substances need to be degraded by enzymes and gut microbiota to decrease their immunogenicity. It has been demonstrated that oral tolerance is not properly achieved without this process. The increased permeability in the gastrointestinal tract to allergens may in part explain the susceptibility of newborns to atopic sensitization. Moreover, failure to properly develop IgA immune responses further hinders the immunological barrier involved in the exclusion of pathogens and allergens in the gut lumen.

Judging from the above information, it would seem logical that feeding infants probiotics would yield long-term positive health effects. Studies have shown that probiotics have the ability to promote the gut defense barrier and even reverse the increased gut permeability associated with children with atopic eczema and food allergies. They have been shown to stimulate IgA responses and certain strains have been shown to contribute to the digestion of antigenic substances to less immunogenic ones. Probiotics have also been shown to alleviate allergic inflammation via TH1, TH3 and regulatory T-cell cytokines. Specifically, administration of Lactobacillus CG before and during breastfeeding has been shown to protect the infant from atopic disease for as long as four years. In infants with eczema, the administration of the same probiotics stain and Bifidobacterium lactis Bb-12 has been shown to improve eczema symptoms. A separate study showed that children with allergy were less often colonized by Lactobacillus spp and bifidobacterium spp and harbored higher counts of the aerobic bacteria Staphylococcus aureus and coliform bacteria.

The Danish study that correlated seropositivity to HAV, H pylori, and T gondii with a decreased atopy interestingly found the opposite correlation with intestinal bacterial pathogens C defficile, C jejuni, and Y enterocolitica. The reason for this discrepancy is unclear, but it is hypothesized that where the first three pathogens cause infection without altering intestinal flora, the latter three can change the composition of gut flora, underlining the importance of gut flora in allergic tolerance. As this study was carried out on 15-69 year old adults, the results suggest that gut bacteria may play a role in not only in the development of tolerance early in life, but also in the maintenance of this tolerance later in life.

Water Quality and Allergy

An emerging area of focus is the study of the influence of drinking water quality on allergic presentation. Older data from Europe and Oceana had shown that the consumption of unpasteurized cow’s milk early in life could independently lower the risk of developing asthma and allergic rhinitis at school age. This phenomenon was thought to be mediated through the exposure to the microbial elements found is such milk. Building upon these studies, Finnish scientists tested the hypothesis that the consumption of untreated water could confer protective effects in a similar fashion. The study was carried out in Finnish and Russian Karelia. School children living on the Russian side of the border used water derived directly from a local lake and its associated rivers or, in a minority of cases, wells. In a majority of cases, no chemical treatment of these raw waters was performed. When chemical treatment was done, it was in the form of heavy chlorination. School children living on the Finnish side of the boarder used water that was alkalized by municipal waterworks. In a majority of cases, the water was also treated with ultraviolet radiation for disinfection. The study found the microbial content levels in the drinking water were inversely associated with atopy in a dose-dependent manner and were determined to be an independent risk factor.

This issue was also investigated in Ethiopia. There scientist found that patients with atopic dermatitis were more likely to have access to piped water and were less likely to use river water as their only source of drinking water . However, the effect of water source was not found to be statistically significant in multivariate analysis. This weak association mirrors data found in Ecuador, also showing a weak association between the consumption of river water and lowered atopy.

It is important to keep in mind, however, that low quality drinking water may be a surrogate marker for some other factor associated with poor living conditions. A Norwegian study has shown that drinking water may spread molds like Penicillium, which has been implicated in the triggering of allergy and asthma. Other studies from Scandinavia have also linked the consumption of mold-contaminated water with allergic reaction. As surface water is not only contaminated with bacteria, it is important to keep the influence of other contaminants in mind.

Doc James (talk · contribs · email) 04:10, 12 August 2011 (UTC)

Would it be appropriate to add information on medication/drug allergies on this page?

I came to this page for basic information and it seems to be lacking that area. I am not qualified to add the information, as I am a seeker of knowledge in this area. 63.81.6.39 (talk) 03:08, 4 September 2011 (UTC)