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Allergy, sensitivity and…stool testing

 Women having an allergic reaction to foods

Gastrointestinal dysfunction and loss of gut microbiome diversity have been associated with an increased risk of IgE allergy, leaky gut syndrome and sensitivities. Sensitivities are inappropriate immune responses to common environmental antigens such as foods or inhalants. As research into gut-mediated immune responses has progressed, non-IgE-mediated food reactions, or sensitivities, are now acknowledged. These food sensitivity reactions are all mediated, directly or indirectly, by IgA, IgG or IgG-immune complexes and complement activation. The management of IgE allergy is different than for food/inhalant sensitivities and both require a basic understanding of the hypersensitivity responses involved. The symptom profiles for IgE and IgG hypersensitivity are usually easy to distinguish, although some symptoms may overlap.

IgE symptoms may present as anaphylaxis (sudden sneezing, coughing or wheezing reaction, difficulty breathing, hives, swelling of lips, tongue, throat, sudden hypotension, sudden GI symptoms) or a less aggressive response; the keynote IgE symptom is consistency. The reaction happens consistently, within minutes to hours, every time food exposure occurs. IgE responses in children may be different, and include symptoms such as rectal bleeding, constipation, colic, dermatitis, chronic nasal congestion, or failure to thrive. IgE allergic responses may be moderated by dose or the presence of IgG4antibodies. IgG4 “competes” with IgE antibodies to block their enzyme activity or protein-protein interactions that cause allergic reactions. IgG4 levels can increase when there is prolonged, chronic exposure to high levels of protein antigens, providing some protection against IgE hypersensitivity. It is important to evaluate both IgE and IgG4 in allergic patients, and it is essential that patients strictly avoid foods that induce allergic reactions.

IgE and IgG4 data for allergy related information.

IgG symptoms are different. Symptoms develop over time and may not become apparent until 1-3 days after a food is eaten, or symptoms may be chronic if a food is eaten frequently. IgG sensitivity to foods may contribute to chronic inflammation, either locally or via systemic symptoms such as autoimmune conditions, migraine, skin rashes, asthma, or fatigue, irritability, nervousness, or gastrointestinal symptoms (indigestion, gas, abdominal cramps or bloating). The keynote symptoms here are delayed response and chronicity of symptoms. Food intolerance (sensitivity) may be a symptom of digestive disorders, genetic enzyme deficiencies, gut microbiome imbalances, as well as the result of IgG or other non-IgE mediated immune responses.   

IgG levels becoming cumulative and worsening symptoms

Allergy or sensitivity reactions in the gastrointestinal system can result in local inflammation and loss of gut barrier functions. The gut mucosa and the immune system may be further influenced by diet and nutrition, and the gut-associated lymphoid tissue (GALT) system uses essential dietary components (such as lipids and vitamins) as modulatory molecules to maintain the gut mucosa and maintain immune tolerance. Some essential vitamins and compounds, such as B-vitamins and short-chain fatty acids, are produced in the gut by bacteria in the gut microbiome. A loss of diversity in the gut microbiome may result in a shortage of essential nutrients and anti-inflammatory signaling molecules. 

Relative commensal abundance results of GI

Knowledgeable clinicians can employ a series of steps to manage both food sensitivity and inhalant allergies, improve tolerance, and provide patient relief:

  1. Consider anti-inflammatory therapies and mast cell stabilization to modulate the immune system. Common supports include quercetin, curcumin, flavonoids, lipoic acid, etc.
  2. Eliminate and rotate foods per US BioTek’s IgG and IgA food sensitivity panels to reduce the likelihood of food sensitization.
  1. Monitor, manage, or eliminate inhalant allergy or mold exposures that may inflame the gastrointestinal tract or induce food-antigen cross reactions. US BioTek offers both IgE mold panels and urine mycotoxin panels in addition to IgE and IgG inhalant profiles for pollens and indoor antigens.
  2. Evaluate and support digestion, gastric pH and the gastrointestinal microbiome using US BioTek’s new GI profiles.

    A sample of GI Advanced Profile and Markers

US BioTek’s stool testing may be used to evaluate digestion, absorption, and microbiome diversity. Based upon the results of a GI profile, a clinician may choose to improve diet quality and/or provide nutritional support. Action steps may include:

  • Normalization of digestion and gastric pH to improve assimilation and minimize IgE- and IgG-mediated food hypersensitivity and food cross-reactions.
  • Improve protein assimilation.  Protein malnutrition has been documented to decrease antibody (IgA, IgG) production and adversely influence the number and inflammatory status of white blood cells in the GALT and the spleen.
  • Support the gut microbiome. Patients that have lost microbiome diversity may require additional nutritional support with vitamins. The intestinal microbiota has the capacity to synthesize a variety of vitamins involved in myriad aspects of microbial and host metabolism, including cobalamin (vitamin B12), pyridoxal-5’-phosphate (active form of vitamin B6) which is a cofactor in a variety of bacterial interconversions of amino acids, pantothenic acid (vitamin B5), niacin (vitamin B3), biotin, tetrahydrofolate (from dietary forms of folate) and vitamin K.  
  • Amino acids threonine, serine, proline, and cysteine are required to promote mucin synthesis and improve intestinal barrier function.
  • Butyrate initiates epigenetic changes in naїve T cells that cause them to differentiate into anti-inflammatory tolerant T-regulatory cells.
  • Glutamine is a non-essential amino acid that supports the function of the intestinal mucosal system and modulates the production of inflammatory cytokines. Animal studies indicate that glutamine helps maintain gut lymphoid tissues and protective fecal sIgA production.  
  • Consider the use of probiotics and fiber to improve the gut microbiome. 
    • Probiotics may moderate IgE inhalant allergy symptoms, in addition to local action in the GI tract. The probiotic yeast Saccharomyces boulardii may protect against Candida colonization; animal studies have shown that Candida may promote sensitization to food antigens.
    • Dietary fiber and resistant starch serve as substrates for beneficial bacteria in the colon; these substrates favorably alter the intestinal microflora, improve short chain fatty acid production (SCFA), increase resistance to illness or infection and reduce colonic pH – all of which improve gut health. A daily intake of 25-30 grams of fiber is recommended, preferably from fiber-rich foods like whole grains and fresh fruits and vegetables.
    • Prebiotics – indigestible fibers that provide a fermentable substrate that allows specific, beneficial changes in the composition and/or activity of the gastrointestinal microflora.  Common pre-biotics include inulin, oligofructose, lactulose, galacto-oligosaccharides, transgalacto-oligosaccharides, psyllium, and whole grains. Evidence indicates that prebiotics may also improve gut barrier functions. 
  • Improve diet quality
    • Eliminate processed foods, trans-fats and known food antigens to reduce systemic and gastrointestinal inflammation.
    • Increase fruit and vegetable consumption and fiber intake to support gut microbiome and short-chain fatty acid production. Plant polyphenols, dietary fiber and resistant starch serve as substrates for beneficial bacteria in the colon.
    • Eliminate and rotate foods to reduce the likelihood of food sensitization or reactivity.

Gastrointestinal dysfunction and loss of gut microbiome diversity induce proinflammatory changes in the gut mucosal lining and immune reactivity. These changes increase the risk of IgE allergy, IgG or IgA food sensitivity, and compromise gut barrier functions. IgE allergy, IgA and IgG sensitivity and stool testing can provide guidance for therapeutic interventions to restore gut homeostasis and immune tolerance required for health and wellness.



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