IgG Type III Delayed Hypersensitivity Reactions Clinical Relevance

Although still controversial in mainstream medicine, IgG food sensitivity testing is starting to accumulate research in support of its clinical utility. For example, 125 patients, identified by an allergist as likely having food allergies, were given blood tests for IgG food reactions. All positive foods were removed for a 6 month period. The allergist considered the treatment a success when a minimum 75% improvement in symptoms occurred. Of the 80 patients who completed the full course, 71% were successfully treated. In particular, there were 11 patients who had positive allergy symptoms, but had negative IgE test results. These patients were all successfully treated by eliminating the IgG food allergens. The allergist concluded that blood tests for IgG reactions to food were clinically useful and much more palatable to patients than the traditional skin prick and oral challenge tests. Although he acknowledged that the lack of blinding and randomization meant the results could be considered anecdotal, the allergist concluded that eliminating reactive foods was useful clinically. [Otolaryngol Head Neck Surg. 2000 ;123(1 Pt 1 ): 48-54].