The quantitation of the allergen specific IgE, which circulates freely in the serum, is a convenient way to diagnose IgE-mediated or immediate type allergies. AIT utilizes the Ala-Stat EIA system to expand the selection of the specific allergens, and to increase the specificity and sensitivity. Their sensitivity is excellent, especially when the total IgE is high (>100 IU/ml), but below that level this test may underestimate the degree of sensitivity or fail to diagnose the allergy. We include a quantitiave total IgE test to aid in the interpretation of the results upon request at a discount. An FDA approved Latex allergen was added to our schedule recently.

Incompletely digested food antigens may gain access to the systemic circulation either through the microvilli by endocytosis or through the intercellular spaces of the gut mucosa in such conditions as the inflammatory bowel disease, coeliac disease, gastroenteritis or the immature mucosa of the infant. IgG type antibodies may be produced against these food antigens without any health consequences or they may form complexes with newly absorbed antigens and can lead to tissue damage when deposited in various organs.

At times, the clinical assessment of IgE-mediated allergies cannot be confirmed by RAST test because of the low level of free IgE in the serum. In those cases testing for the receptor-bound or cell-bound IgE may by utilized as an indispensable diagnostic tool. The Basophil Histamine Release (BHR) assay is performed by challenging living basophil leukocytes in whole blood with serial dilutions of allergens, thereby obtaining a dose response curve of histamine release (response for each allergen). The BHR has excellent correlation with skin test, bronchial and oral challenge tests. The choice of allergens is unlimited. Even small molecules (drug, sodium metabisulfite, etc.) can be tested by this technique, as well as non-IgE-mediated histamine releasers, such as radiographic contrast media.

Some companies offer quantitative tests for some of the mediators released into the blood and tissues during an allergic, anaphylactic and anaphylactoid reaction. Histamine is released from basophils and mast cell quickly and metabolizes rapidly. Elevated histamine level in the plasma, obtained a few minutes after an event confirms the anaphylactic nature of the reaction. Urine, collected within a few hours, may also show elevated histamine.

Auto antibodies are produced against “self” antigens and have an immunopathologic role in many important disease entities. The appearance of certain autoantibodies, like those produced against the beta islet cells of the pancreas, precede the development of insulin-dependent diabetes mellitus by years – as it reflects the destruction of the islet cells. Screening of blood relatives for anti-islet cell antibodies is good preventive medicine. IAA and ICA tests identify the prediabetic state. Hemoglobin AIC is useful for detecting diabetes and monitoring carbohydrate control.

An elevation in the level of the IgG, IgM and IgA antibodies specific to the cytoplasmic protein of the pathogenic fungus Candida Albicans is an indication of either an infection by C. albicans, or the overgrowth of the fungus in the intestine to the point where C. albicans antigens enter the circulation.

Helicobacter pylori has been shown on histological sections to colonize in the gastric and duodenal mucosa in association with antral (type B) gastritis and duodenal ulcers. At the same time there are elevated levels of H. pylori-specific IgM and IgA antibodies in active disease and IgG indicating past exposure. The detection of these antibodies can be a useful test for chronic gastritis and peptic ulcers.