Rates of Antibiotic-Associated Infections in Patients Following Removal of their Penicillin Allergy Label

RATIONALE: Most patients labeled with penicillin “allergy” are not in fact allergic. A 2014 study by Macy et al. found hospitalized patients labeled with penicillin allergy have increased rates of infections compared to controls for infections such as C difficile (2.9% vs 2.4%), MRSA (3.0% vs 2.6%), and VRE (0.6% vs 0.5%).

METHODS: We reviewed a database of patients from Parkland Memorial Hospital who had undergone inpatient penicillin skin testing and challenge as part of a proactive testing program. Patients with negative tests had their penicillin allergy removed from their charts. Rates of infection with C difficile, MRSA, and VRE up to 90 days after penicillin testing (highest rate of C difficile occurrence) was assessed by review of the EMR.

RESULTS: A total of 223 patients with negative penicillin tests were evaluated who had at least 90 days of follow-up data. Five patients (2.2%) developed C difficile infections in the 90 day period post testing; five patients (2.2%) developed MRSA infections, and another 5 patients (2.2%) developed VRE infections.

CONCLUSIONS: Rates of C. difficile and MRSA in hospitalized patients who had removal of their penicillin allergy are comparable to those reported in patients without penicillin allergy.