The diagnostic value of the histamine release test in food allergy.

One hundred and nine patients were selected in this study. All had food allergies (Urticaria, Quincke's Oedema and Bronchial Asthma) diagnosed by either clinical history or skin test results later confirmed by oral challenge. Since many of these patients had multiple sensitivities to various food allergens, the study was performed on 175 blood samples classifying the results according to personal history and results of the skin test. The diagnostic value of histamine release in whole blood of a patient suffering from food allergy is optimally reliable. The study is complemented by providing a better understanding of the dynamics involved in the hypersensitivity response. The results from this comparative study with RAST, once again demonstrate the uselessness in using this technique in food allergy since the existence of other cytotropic antibodies, IgG4 capable of provoking the basophil to produce a clearly detectable and significant histamine release has been well demonstrated. Once again the importance of other antibodies which are not exactly cytotropic or anaphylactic (IgG, IgM, etc.) in nature in hypersensitivity response is brought to light. These are readily detected with a great degree of reliability (78%) using hemagglutination. This method is highly sensitive and is strongly recommended in the diagnoses of allergy because of its simplicity and affordability. The study of the parameters studied shows us once again that there are several mechanisms involved in the hypersensitivity response as well as a variation from one individual to another depending, of course on the class of antigen. Finally we must keep in mind the complexity of the antigen involved in food allergies which in many cases are haptenic.