Study on Patients Who Underwent Suspected Diagnosis of Allergy to Amide-Type Local Anesthetic Agents by the Leukocyte Migration Test

ABSTRACT Background: There are problems in diagnosis of allergy to amide-type local anesthetic agents (ALAs), because definitive diagnosis is not obtained by in vivo tests, which are used for the diagnosis. Consequently, patients may be exposed to risk. There are few diagnoses based on in vitro tests, and there are almost no relevant studies. Methods: Authors examined involvement of allergic reaction using the leukocyte migration test (LMT) through multiple standpoints in 43 patients who underwent suspected diagnosis of allergy to ALAs. Results: Rate of LMT-positives was 54%, and especially the positive rate of lidocaine hydrochloride preparations was significantly high. In 15 positives to lidocaine hydrochloride preparations, all cases were indicated as positive in a test with drugs containing antiseptic agent, but only 3 cases were indicated as positive in a test with lidocaine hydrochloride alone. In addition, test with paraben was conducted in 4 cases; 2 cases were confirmed as positive. In relevance of histories of drug or food allergies, development rates of ALAs-allergies were the highest in both allergies, and were 35% and 13%, respectively. Conclusions: There is a high possibility that these adverse reactions were caused by pseudoallergy to drug. Even by allergic reactions, it was assumed that 80% of them might be caused by antiseptic agents such as paraben. In addition, it was suggested that ALAs, especially lidocaine hydrochloride preparations have high antigenicity (sensitizing property). Furthermore, it was considered that patients with past history of drug or food allergies have a high potential for manifestation of the reactions.