Evaluation of the Potential Risk Factors for Drug-Induced Anaphylaxis in Adult Patients.

Aim: To investigate the potential risk factors in patients who have experienced anaphylaxis from drugs.

Method: The study included 281 adult patients (median age 40 years; 76.5% female) who experienced immediate types of hypersensitivity reaction to a drug. The patients were divided into an anaphylaxis group and a nonanaphylaxis group. The anaphylaxis group was diagnosed according to the criteria of the World Allergy Organization. Skin testing with culprit drugs was performed. In the nonanaphylaxis group, drug provocation tests were performed with culprit drugs, including aspirin or diclofenac, to determine nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity. Atopy was determined by skin prick tests with the common inhalant allergens. Patients' demographics, clinical features, and baseline tryptase and total IgE levels were compared between the 2 groups.

Results: The median interval between the last reaction in the patient's history and the study evaluation was 7 months (range 1-120 months). In 52.3% of the patients, reactions were defined as anaphylaxis. The most common culprit drugs were NSAIDs (56.9%) and β-lactams (34.7%). The culprit drugs were used parenterally in 13.2% of the patients. 34.9% of the patients had comorbid diseases and 24.6% used additional drugs, the most common being antihypertensives (10%). Atopy was determined in 28.8% and 28.1% of the patients were smokers. The median serum level of baseline tryptase and total IgE was 3.5 µg/L and 77 kU/L, respectively. In 46.3% of the patients, skin tests with culprit drugs were positive and the positivity ratio was higher in the anaphylaxis group (p = 0.002). Anapyhlaxis was more common in patients who were: hypertensive, atopic, using angio-tensin-converting enzyme inhibitors/angiotensin receptor blockers, and received the culprit drug parenterally (p = 0.034, p = 0.04, p = 0.03, p = 0.035, p = 0.013, and p < 0.001). In the multivariate analysis, it was observed that the parenteral usage of the drug and the presence of atopy were significantly higher in the anaphylaxis group (p < 0.001, odds ratio [OR] = 20.05, confidence interval [CI] 4.75-88.64; p = 0.012, OR = 2.1, CI 1.17-3.74). Age, smoking, family history, and serum levels of baseline tryptase and total IgE did not differ between groups.

Conclusion: The parenteral route and atopy increase the risk of drug-induced anaphylaxis. IgE-mediated sensitivity to the culprit drug seems to facilitate anaphylaxis.