History-based preoperative evaluation of antibiotic-related allergies and design of an easy to use questionnaire.

Abstract

An unconfirmed history of antibiotic allergies may negatively influence prescribing patterns for preoperative antibiotic prophylaxis and increase rates of postoperative wound infections through unnecessary use of alternative antibiotics. After a literature search, we developed aquestionnaire for the structured collection of antibiotic allergy history in the anesthesia consultation center and tested it over 2 years at atertiary care hospital under everyday conditions as part of aquality assurance project. All data were evaluated completely anonymously in the context of standard care. After refining the questionnaire, we analyzed 4866 recorded optimized questionnaires, of which51 were incomplete. An antibiotic allergy was denied 4312times and affirmed 503times, which corresponds to 10% in our sample. The most frequent single substances or groups in the 503 respondents with apositive history of antibiotic allergy were penicillin in 271 (54%), amoxicillin in65 (13%), an unknown single agent in50 (10%) and multiple substances in25 (5%). The reported event occurred more than 10years ago in 192 (38%) of the respondents, less than 10years ago in 116 (23%), and 195 (39%) could not provide information. The time from exposure to symptom onset was less than 1h in96 (19%), between 1 and 24 h in75 (15%), more than 24 h in 106 (21%), and the remainder could not provide information. Allergy-specific treatment was recalled by75 (15%) respondents, 287 (57%) reported not having received specific treatment, and the remainder could not recall. Aspecific allergy test was reported by55 (11%) respondents, 337 (67%) said no allergy test had been made, and the rest could not recall. Asubstance-specific allergy passport was issued in80 (16%) respondents. According to expert assessment, symptoms compatible with an IgE-mediated reaction were present in96 (19%) of the respondents. An IgE-mediated reaction was considered possible in70 (14%) and could be excluded by history in 337 (67%) of respondents. Out of 503 respondents with apositive history 51(10%) could not remember the allergic substance but7 (14%) of the 51reported symptoms compatible with severe anaphylaxis or anaphylactic shock and6 of the51(12%) reported symptoms possibly related to an IgE-mediated reaction. Our survey revealed approximately 10% of respondents reporting an antibiotic allergy, which is in the upper range of data published in international literature and corresponds most closely to American data. Thus, the topic is also relevant to German anesthesia consultation centers, given the high rate of respondents who could have been "delabeled" based on the comprehensive assessment of their history. More expert allergy testing is needed in patients who report symptoms related or probably related to an IgE-mediated reaction. In our opinion, aspecial issue exists in those patients who did not remember the exact antibiotic but reported symptoms compatible with severe anaphylaxis putting them at high risk of unintended re-exposure.