Prevention of nonsteroidal inflammatory drug-induced urticaria and/or angioedema.

BACKGROUND: Urticaria and/or angioedema (U/AE) are the most frequent and less severe forms of nonallergic hypersensitivity reactions to nonsteroidal anti-inflammatory drugs (NSAIDs). Management of NSAID-induced U/AE includes (1) the avoidance of the culprit drug and of cyclooxygenase (COX) 1 inhibitors, (2) the use of weak COX-2 inhibitors, and/or (3) desensitization to aspirin. Because these possibilities may have drawbacks, we tested the possibility of preventing NSAID-induced U/AE by the administration of antihistamines and/or a combination of antihistamines and leukotriene antagonists. OBJECTIVE: To test the preventive effect of antihistamines and/or leukotriene antagonists on the development of U/AE in patients with a history of NSAID hypersensitivity confirmed by a positive challenge result. METHODS: A single, placebo-controlled, oral challenge using the culprit NSAID was applied to 65 patients with a history of NSAID-induced U/AE. In the case of recurrence of the symptoms, another oral challenge was performed under premedication with antihistamines alone or combined antihistamines and leukotriene antagonists. RESULTS: A total of 59 of 65 patients (90%) tolerated a normal dose of NSAID, confirming previous data on the poor reproducibility of nonallergic hypersensitivity reactions to NSAIDs on challenge. Of the 6 patients who experienced recurrence of the U/AE on NSAID challenge, antihistamines and combined antihistamines and leukotriene antagonists prevented the hypersensitivity reactions in 2 and 3 of them, respectively. Only 1 patient still developed a moderate NSAID-induced urticaria despite the double premedication. CONCLUSION: Treatment with NSAIDs at normal doses is possible and well tolerated in patients who have experienced NSAID-induced U/AE, which could be prevented by the concomitant use of antihistamines and leukotriene antagonists.

Immediate allergic hypersensitivity to quinolones associates with neuromuscular blocking agent sensitization.

BACKGROUND: We identified a case of quinolone allergic hypersensitivity associated with quaternary ammonium (QA) sensitization, the allergic determinant of neuromuscular blocking agents (NMBAs). Concomitant sensitization to several chemically different drugs is rarely reported and raises the question of a nonfortuitous association. OBJECTIVE: We evaluated a potential association between quinolone immediate allergic hypersensitivity and NMBA sensitization. METHODS: QA-specific IgE detection was prospectively performed in 26 patients who presented an immediate hypersensitivity reaction to quinolones: 17 with a confirmed allergic hypersensitivity and 9 with allergic hypersensitivity not confirmed. We also included a control population of 88 outpatients without a history of quinolone or NMBA hypersensitivity. Patients with positive QA-specific IgE benefited from a NMBA allergologic workup. RESULTS: The prevalence of positive QA-specific IgE was significantly higher in patients with quinolone allergic hypersensitivity (9/17, 53%) compared with patients with allergic hypersensitivity not confirmed (1/9, 11%) than in controls (3/88, 3.4%). In the quinolone allergic population, ofloxacin elicited inhibition of the 4 positive QA-specific IgE sera tested, in a dose-response manner. Among the 9 patients with positive QA-specific IgE, the QA sensitization (positivity of specific IgE) was confirmed by positive skin tests and/or basophil activation tests to at least 1 NMBA in 5 of the 7 tested patients. CONCLUSION: We report here the first documentation of a high prevalence of QA sensitization in patients with quinolone allergic hypersensitivity. These results suggest a new way for NMBA sensitization. It thus seems appropriate to investigate NMBA sensitization when quinolone allergic hypersensitivity is diagnosed.