Allergic clinical symptoms and distribution of stimulation index of drug lymphocyte stimulation test for local anesthetics

The Drug Lymphocyte Stimulation Test (DLST), recognized for its safety as an allergy diagnostic modality, has been acknowledged for its utility in diagnosing drug-induced pathological conditions. However, reports elucidating DLST outcomes concerning local anesthetics are notably scarce.

An exhaustive analysis was conducted on the DLST results pertaining to local anesthetics derived from 571 patients presenting with suspected allergies to these specific agents.

Remarkably, Stimulation Index (SI) > 1.8 was discerned in 11.4% and 7.8% of patients exhibiting hives or swelling subsequent to the administration of local anesthetics, surpassing the incidence observed in those experiencing post-injection discomfort. Additionally, SI > 3.0 was observed in 3 cases with lidocaine, 3 cases with prilocaine, and 1 case with mepivacaine. The distribution of SI exhibited a non-normal pattern for all three tested local anesthetics. Noteworthy is the case of a singular patient registering an SI of 1.84, who also yielded a positive challenge test, conclusively confirming an allergy to lidocaine.

The DLST, holding promise as a potentially invaluable tool in identifying the causative factors behind adverse reactions to dental local anesthetics, lacks sufficient evidence to substantiate its efficacy definitively at present.

DLST, coupled with intradermal testing and challenge testing, may be elucidated in patients exhibiting indicators of suspected local anesthetic allergy.