A penicillin allergy label has been associated with significantly higher rates of MRSA and VRE colonization and correspondingly, poorer clinical outcomes. However, there are limited data examining the association between any antibiotic label and colonization rates. We sought to evaluate for a relationship between patients with an antibiotic allergy and prevalence of MRSA or VRE colonization.
We retrospectively reviewed all patients with an MRSA surveillance culture between December 15, 2014 and January 31, 2015 or a VRE surveillance culture between January 1, 2013 and January 31, 2015 at our institution. Our primary objective was to evaluate the prevalence of MRSA or VRE colonization among patients with and without antibiotic allergies. Bivariate analysis included chi-square and student t-test to determine statistical significance for categorical and continuous variables, respectively.
RESULTS: We included a total of 1053 unique patients screened for MRSA and 290 unique patients screened for VRE. The rate of MRSA and VRE colonization was 6.0% (62/1053) and 32.4% (94/290) in our cohort. Antibiotic allergies were documented in approximately 1 out of 3 patients, 338 (32.1%) for the MRSA group and 94 (32.4%) for VRE group. There was a significant difference in MRSA colonization between patients with and without an antibiotic allergy (45.2% vs. 31.3%, p=0.034). In contrast, there was no significant difference in VRE colonization between patients with and without an antibiotic allergy (12% vs. 47%, p=0.10).
An antibiotic allergy label was associated with significantly higher rates of MRSA colonization but not with VRE colonization.