Published Online: July 2, 2015
The incidence of anaphylaxis in Europe and the United States ranges from three to 300 per 100,000 persons per year, with a lifetime prevalence of 0.05 to two percent. The incidence of anaphylaxis has increased in westernized countries with hypersensitivity drug reactions (HDRs) being the most common cause. Epidemiologic data is limited for drug-induced anaphylaxis (DIA) in Latin America.
Jares et al, in a study published recently in The Journal of Allergy and Clinical Immunology: In Practice, sought to identify the drugs most commonly implicated in DIA in different Latin American countries, and to describe the clinical presentation and diagnostic testing performed to confirm DIA and the treatment provided for these reactions. The study was a cross-sectional study to assess the prevalence and characteristics of DIA using the European Network of Drug Allergy (ENDA) questionnaire, conducted in 22 allergy units from 11 Latin American countries. DIA was defined as a moderate or severe reaction occurring less than 24 hours after an implicated drug administration associated with urticaria and/or angioedema (U/A), and if there was at least one respiratory, gastrointestinal, and/or cardiovascular symptom. Patients with two or more of the following also qualified: respiratory compromise, persistent gastrointestinal symptoms, and/or cardiovascular (CV) symptoms. As each center used its own standard order of procedures to investigate drug reactions in their patients, this study illustrates an accurate depiction of which approaches Latin American allergists favored in establishing a diagnosis of DIA.
Among the 1,005 HDRs evaluated in our database, 264 (26.3%) patients met diagnostic criteria for DIA. There were no specific host risk factors identified for DIA. However, in contrast to previous reports, asthmatic and atopic patients presented with less severe DIA reactions. More than 15% of the patients in this study experienced a previous HDR with the same drug. Cutaneous and respiratory symptoms were the most common manifestations of DIA. Of note, more than 45% of the patients had CV involvement, which was more prevalent in elderly patients compared to children/adolescents and adult groups. NSAIDs were the most common drug group implicated in all age groups. Selective NSAID anaphylaxis accounted for about one third of all NSAID anaphylaxis cases. Physicians preferred drug provocation tests (DPTs) over other diagnostic approaches, and this was performed in more than 40% of cases, primarily to NSAIDs. Slightly more than 30% of DPT elicited positive reactions. Epinephrine was used in less than 30% of all cases to treat DIA and in approximately 40% of cases when there was CV involvement.
The results of this study emphasize the need to improve dissemination and implementation of anaphylaxis guidelines to primary care and emergency department physicians in Latin American countries.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.