Aug
31
2013

Peanut Allergies Are Deadly

Introduction

This article is about “peanut allergies are deadly”. In the US 1.5 million suffer from peanut allergies (Ref.1). People who have peanut allergies have to avoid peanuts and foods that contain even traces of peanuts lifelong. Here is a recent example of a 13-year old girl who died at a camp when she tried food contaminated with peanuts. Before we discuss peanut allergies in detail, we need to review first how the immune system is functioning.

How the immune system is primed to develop an allergy

Our immune system knows the difference between our own body components and substances that come from the outside. Scientists call this tolerance to our own surface proteins; and scientists call it an immune reaction that is mounting as a reaction to anything different from the surface antigens. There are different cells that make up the immune system. One of the main working cells of the immune system are the lymphocytes. A subtype are B cells that originate from the bone marrow producing antibodies when an immune reaction occurs. Antibodies fit like a lock and key to the surface of an antigen, in this case the peanut protein. T helper cells are T lymphocytes (thymus derived lymphocytes). They help the B cells to recognize the difference between the own protein components and the outside components.

IgE antibodies directed against peanut protein

There are also T killer cells, which when parasites or viruses enter the body activate them. With regard to peanut allergies, it is the B cells and T helper cells that interact. The B cells produce a powerful, very specific IgE antibody directed against peanut protein. There are memory B cells, which continue to produce these specific anti-peanut protein antibodies. They can cause severe allergic reactions when future exposure to peanuts (even traces) occurs. The more often a person allergic to peanuts encounters traces of peanuts, the more  the immune system gets boosted. This produces even more antibodies of the IgE type through reactivated B memory cells (Ref. 2). 98% of the population does not react to peanut exposure with allergies. But the other 2% who may have genetic susceptibility factors that predispose them to this often develop life-threatening reactions. These have the name “anaphylactic reaction”.

What is an anaphylactic reaction to peanuts?

The most extreme form of allergies involving IgE antibodies can cause anaphylaxis. In the beginning stages of a peanut allergy there may only mild symptoms such as hives on the skin, itching and tingling around the mouth, a runny nose, a scratchy throat, wheezing, stomach cramps, vomiting or diarrhea. However, with a more severe allergy an asthma attack can develop. In this case the blood pressure drops leading to fainting or shock. In addition, severe airway obstruction in the throat or lungs can cause suffocation.

I vividly remember an 11-year-old boy who arrived by ambulance in the emergency room of the hospital where I was working as the on-call physician. He had a hard time talking as his throat was swelling up as part of his anaphylactic reaction, within minutes he passed out completely (shock). Fortunately, an anesthetist was in the department and could intubate him very quickly.

Period of unconsciousness

However, despite adrenaline treatment, oxygen by artificial ventilation and high doses of corticosteroid drugs he did not wake up until 10 hours later. In retrospect it turned out that he had eaten some crackers of a familiar brand that he knew as being free of peanut flour. However, he saw an ad that the same brand of crackers was available as cheese crackers and he tried one of these. This prompted his admission to the hospital. The parents read the ingredients later: the label on the cheese crackers noted in small print that the flour of the cheese crackers contained peanut flour! Always read labels, even if it is a familiar brand! Fortunately for this boy he did not have brain damage from the time of his unconsciousness. He has been extremely careful since and is reading labels and avoiding unknown food items.

Peanut Allergies Are Deadly

Peanut Allergies Are Deadly

Cross-reactions between peanuts and other allergens

Allergies can be made worse when a person has inhalant allergies from pollens of trees or grasses that can share protein components from protein found in foods. The latest findings are that there are cross allergies between Fenugreek and lupine, which are both legumes, as are peanuts, so there are common antigens present in their proteins. A mouse-testing model has shed more light on this. Fenugreek has been shown to control mild diabetes by improving insulin resistance, but it cannot be consumed by persons who are highly allergic to peanuts because of the cross allergy mentioned.

There are other possible cross allergies to legumes like lentils, soy and chickpeas.

Other factors that can cause allergies to get worse

In the past the RAST test was often used.  This is a blood test for common food allergies that can cause severe allergic reactions like egg, milk, peanut, tree nuts, wheat, crustacean shellfish and soy. However, since about 2010 this has been replaced by the more sensitive ImmunoCAP Specific IgE test. Children who have food allergies to egg, milk, wheat, nuts, peanuts and soy often outgrow these allergies when they age, in other words their immune system can develop tolerance to many of these foods. Not so with peanut allergies! They tend to be very persistent.

Immune responses to food allergies are complicated

There are complications with immune responses to food allergies. They contained immediate type immune reactions and delayed type immune reactions. Allergists investigate the immediate immune responses with the above mentioned ImmunoCAP Specific IgE test. They can measure the delayed immune responses using the ELISA test. Positive IgE antibody tests for peanut protein are a marker that the person likely has more other allergies. An allergist should investigate them in that regard (Ref. 2).

New wheat varieties complicate the lives of people with allergies

What complicates the allergy sufferers’ lives even more is the fact that new wheat varieties were introduced. This happened in the 1970’s. The new wheat has the name Clearfield wheat. It has a much higher gliadin (gluten) and lectin content than the old wheat varieties. As a result of exposure to this new type of wheat gluten intolerance and leaky gut syndrome have increased substantially in the world population (Ref.3). In addition, genetically modified foods like soy, corn, sugar beets, canola and others have challenged the immune system of sensitive humans even more.

Autoimmune diseases from GMO food and modern wheat

We do know that some people can develop autoimmune diseases from GMO foods and modern wheat, and this may be the reason that a host of diseases that belong into this disease category (MS, rheumatoid arthritis, Hashimoto’s thyroiditis, ankylosing spondylitis etc.) are much more common now than in the past. The geneticists developing GMO foods were unaware how sensitive the immune system is.  The immune system detects a few different amino acid sequences in a protein mounting a strong immune response to it.

Treatment for peanut allergies

The key for sufferers from peanut allergies is to avoid exposure to it. Read labels and use common sense. If a food item has no label, do not attempt to eat it. Food manufacturers often mix peanut flour into the dough of crackers. But not every product has a label that identifies whether peanut flour is in it. Alternatively it says so only in fine print. With peanuts the antibodies usually circulate in the blood life long. The reason is that the B memory cells do not diminish and experience reactivation very quickly on repeat exposure. At this time they produce antibodies again. As exposure to peanuts can cause severe asthma or anaphylactic shock, it is important to carry an EpiPen with you and to know how to use it.

Oral immunotherapy

In Europe attempts have been made to develop an oral desensitization method for food allergies including peanut allergies, but it has not produced concrete results yet. Recently, however, research from Texas, USA showed that it is possible to desensitize patients with peanut allergy by oral desensitization. In Australia where food allergies are more prevalent than in the US, tolerance to peanut, nut and shellfish allergies is being pursued by oral immunotherapy. Another group in Australia has developed a vaccination method using peptides, which are a sequence of amino acids, but shorter than the full peanut protein. It appears that this is the future direction of treatment for peanut and other IgE allergies: a kind of vaccination treatment to induce competing antibodies, which will neutralize the allergic IgE antibodies.

Conclusion

Peanut allergies have become more troublesome as the food industry has mixed peanut flour into Thai sauces, drinks, cookies, crackers and such. The person allergic to peanuts must read food labels and eat as much single-ingredient natural food as possible. This goes against the tendency of food processors who produce foods with a long rat tale of ingredients. If you see a label “may contain nuts or peanuts”, stay away from this product, as it is safer. Always carry an EpiPen or Twinject with you, just in case you develop an anaphylactic reaction (you only have a few minutes to stop the allergic reaction with adrenaline). In the future vaccination with a peanut protein specific peptide vaccine as mentioned regarding the Australian research, will probably become the treatment of choice.

More information on status asthmaticus (an acute asthma attack).

References

1. Adkinson: Middleton’s Allergy: Principles and Practice, 7th ed. Chapter: Food Allergy. © 2008 Mosby.

2. Mandell: Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases, 7th ed.© 2009 Churchill Livingstone.

3. William Davis, MD: “Wheat Belly Cookbook. 150 Recipes to Help You Lose the Wheat, Lose the Weight, and Find Your Path Back to Health”. HarperCollins Publishers LTD., Toronto, Canada, 2012.

Jun
01
2008

Boost Babies’ Health with Mom’s Diet

Prenatal supplements and good advice on proper nutrition during pregnancy have long been included in proper prenatal care. Importance has been placed on folic acid to prevent neural tube defects in the fetal development. Calcium is recommended, often in the form of dairy products, but it does not end there: just swallowing the supplement and adding some more milk may be helpful but not quite enough. Certain dietary habits have been found more beneficial, such as the eating habits in the Mediterranean countries. A research team from the University of Crete in Heraclion, Greece included women who were involved in antenatal care at all general practices in Menorca, Spain. The study took place in the time frame of 12 month starting in 1997. After six and a half years 460 children were also included in the analysis.

Dietary habits were studied and assessed by food questionnaires and the children were assessed for the development of allergies and asthma.

Boost Babies’ Health with Mom’s Diet

Boost Babies’ Health with Mom’s Diet

The children of mothers who consumed the most vegetables, fish and legumes were almost 80% less likely to have persistent wheeze and more than 40 % less likely to have allergies. The results are consistent with the fact that a high level of adherence to the Mediterranean diet during pregnancy is protective not only to the mother but also to the child.

More information about prenatal visits (where nutritional habits are checked as well): http://nethealthbook.com/womens-health-gynecology-and-obstetrics/pregnancy-labor-delivery-2/prenatal-visits/

Reference: The Medical Post, April 22, 2008, page 25

Last edited December 18, 2014

May
01
2008

Tree Pollen Connected With Mood Disorders

Seasonal affective disorder (SAD) does have its grip on people who react to a lack of sunlight in the winter month. As a result depression in the winter season is not uncommon. Some people just report it as feeling “down” and “tired” or report a lack of energy. Despite all the reports about SA, epidemiological studies have shown that the rate of depression is not the highest in dreary months like January or February but it spikes in the months of April and June. Dr.Teodor Postolache, a psychiatrist at the University of Maryland made a recent presentation at a meeting of the American Acadamy of Allergy, Asthma and Immunolgy delving into the reason for this finding. He compared the exposure of tree pollen which triggers a cytokine release to a tsunami.Virtually no outdoor allergens are present in the winter months, but with the release of tree pollen people who are vulnerable to allergies are exposed to massive amounts of allergens. The released cytokines may affect brain function and behaviour, resulting ultimately in changed cortisol levels and an altered serotonin metabolism. After breathing the cytokines are already released in the nose and they can continue their action in the prefrontal brain area where the centers for mood, anxiety and impulsivity are located. Dr. Postolache and his colleagues confirmed that individuals with a history of allergy and asthma had a 2.5 fold of suicide compared to controls and those with allergic rhinitis had a 1.7 fold higher risk.

Tree Pollen Connected With Mood Disorders

Tree Pollen Connected With Mood Disorders

For the first time it could also be demonstrated that cytokine levels in suicide victims were significantly elevated in the orbitofrontal cortex, the brain area that affects mood. Intranasal corticosteroids in the form of nosedrops can bring significant relief to allergy sufferers, and Dr. Postolache and his team will examine the benefits of intranasal corticosteroids closer  in a clinical study. Whereas systemic corticosteroids have shown a negative impact on mood disorders and depression, the local application of a nasal spray or drops is geared to abolish the pathways from the nose to the brain for the inflammatory cytokines.

More information on seasonal rhinitis: http://nethealthbook.com/ear-nose-and-throat-diseases-otolaryngology-ent/nose-problems/allergic-rhinitis/

Reference: The Medical Post, April 1, 2008, page 1, 34

Last edited November 3, 2014