001413 - Approach to penicillin allergy

Beta-lactam (BL) antibiotics are frequently used as a first step of infection treatment all over the World. However, they can cause allergic reactions including anaphylaxis. Although history and examination are important in BL allergy, skin tests and oral provocation tests (OPT) are also performed for a definitive diagnosis. Herein, results of penicillin tests were revised to show their reliability.

A specific standardized skin test kit for penicillin (DAPR, Diater Laboratories, Spain) was performed to 43 patients with suspected penicillin allergy in Allergy Clinic of a University Hospital with intensive care settings.

Of 43 patients, 11.6% (n:5) showed positivity in DAP tests. In their history of these patients, 1 patient had anaphylaxis, 3 patients had urticaria, and 1 patient had angioedema. In 30 patients with negative DAP test results, oral provocation test (OPT) with amoxicillin were performed and in 2 (7.6%) patients OPT resulted positive with early reaction as anaphylaxis. In 75 patients OPT with alternative antibiotics to penicillin were done, since they had a history of anaphylaxis or generalised skin rash. Alternative antibiotics to penicillin in OPT were ciprofloxacin (Quinolone) for 45 patients, moxifloxacin (Quinolone) for 4 patients clarithromycin (Macrolide) for 48 patients, clindamycin (Lyncosamide) for 17 patients, azithromycin (Macrolide) for 7 patients which all results negative.

This study shows that DAP is a reliable test that can be used before OPT. However in a minor group with suspected penicillin allergy, OPT is still necessary to make a diagnosis. In cases with positive results to penicillin other groups of antibiotics as an alternative drug should be done.