Drug Hypersensitivity Reactions in Patients with Clonal Mast Cells Disorders

Abstract

S U N D A Y 393 Drug Hypersensitivity Reactions in Patients with Clonal Mast Cells Disorders Carla Lombardo, Patrizia Bonadonna, MD, CME, Roberta Zanotti, Gianenrico Senna, MD, Giovanni Passalacqua, MD; Allergy Unit, Azienda ospedale Universit a di Verona, Italy, Allergy Unit of Azienda Ospedaliera Universitaria Integrata Allergy Unit, Verona, Italy, Department of Clinical and Experimental Medicine, Haematology Section, University of Verona, Italy, Allergy Unit, Verona, Italy, University of Genoa, Genoa, Italy. RATIONALE: The occurrence and characteristics of drug-induced anaphylaxis in patients with clonal mast cell disorders (CMD) is largely unknown. In this single-center study we assessed the prevalence of drug hypersensitivity in a population of mastocytosis patients. METHODS: All patients with ascertained CMD, followed in our clinic were asked to fill a questionnaire about previous adverse drug reactions. Patients with drug hypersensitivity underwent to oral challenge tests (OCT) with alternatives drug. RESULTS: 158 patients were enrolled; 89 (56.3%) male, mean age 52614 years. In 58.9% of patients the diagnosis of CMD was done after hymenoptera sting anaphylaxis, and in 7% after drug anaphylaxis. Fiftyone (32.3%) patients reported a total number of 78 drug hypersensitivity reactions, 16 (31.4%) had 2 or more episodes and 7 (13.7%) with different drug classes. The most frequently involved drugs were NSAIDs (54.9% of patients, 43 episodes), and antibiotics (41.2% of patients, 25 episodes). Anaphylaxis occurred in 11/28 (39%) patients with NSAIDs reactions and in 10/21 (47.6%) patients with antibiotics, mostly amoxicillin (66.7%). Thirty-eight OCTwith alternative NSAIDs (13 nimesulide, 14 etoricoxib, 6 meloxicam, 3 paracetamol and 2 aspirin) were performed and only 1 patient had rhinitis during aspirin challenge. Thirty-seven OCTs with antibiotics (15 clarithromycin, 13 ciprofloxacin, 2 clindamycin, 2 doxyciclin, 2 amoxicillin and 3 cefuroxime) were performed without adverse reactions. CONCLUSIONS: In our population the prevalence of self reported drug hypersensitivity was 32.3%, that is higher than in general population. The most involved drugs are antibiotics and NSAIDs. OCT with alternative drugs are safe and useful tools for a diagnosis.