Methods: This was a cross-sectional study assessing all patients admitted to a tertiary referral teaching hospital over a 5-month period in 2016. All newly admitted patients were prospectively screened for the presence of an antibiotic allergy documented in their electronic medical record. Unless unable to participate, patients were interviewed regarding the detailed nature of their antibiotic allergy. Information regarding allergy documentation, medical condition and antibiotic use was obtained from medical records.
Results: 3855 patients were screened, 553 (14.35%) had an AAL, and 352 were interviewed. There were 426 allergies, 276 (64.8%) towards a penicillin. Only 52% of patients had a convincing history consistent with antibiotic allergy, and 48% of these were mild cutaneous reactions. It was felt that de-labelling and direct re-challenge would be relatively safe in 70% (298/42) of AALs (if the mild cutaneous allergic group were included). In patients who were prescribed antibiotics during study admission, 25.6% (41/160) of antibiotic prescriptions in our cohort were found to be inappropriate in patients with AALs.
Conclusion: Direct re-challenge based upon clinical grounds appears to be a feasible clinical option in many patients with AALs and would allow de-labelling of these patients. The major barriers continue to be patient acceptance and risk of severe adverse reactions. Our study also found that major improvements could be made in the specific documentation of allergy and also in selection of guideline-recommended alternate antibiotics.
- Joint Task Force on Practice Parameters. Drug Allergy: An Updated Practice Parameter. Ann Allergy Asthma Immunol. 2010; 105(4): p. 259-273.