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Published on: August 30, 2018
The Penicillin Allergy Delabeling Program: A Multicenter Whole-of-Hospital Health Services Intervention and
Kyra Y L Chua1, Sara Vogrin2, Susan Bury1,3
1Department of Infectious Diseases and Centre for Antibiotic Allergy and Research, Austin Health, Heidelberg, Australia.
Insights
Hospitalized patients with low-risk penicillin allergies can be safely delabeled through direct assessment or oral challenges. This improves antibiotic prescribing, increasing narrow-spectrum penicillin use and reducing restricted antibiotic utilization.
Area of Science:
- Infectious Diseases
- Clinical Pharmacy
- Health Services Research
Background:
- Penicillin allergies are linked to poorer patient outcomes and antimicrobial stewardship.
- A whole-of-hospital program was implemented to evaluate inpatient penicillin allergy delabeling for low-risk cases.
Purpose of the Study:
- To assess the efficacy of inpatient delabeling for low-risk penicillin allergies.
- To evaluate the impact of delabeling on antibiotic utilization and prescribing patterns.
Main Methods:
- Adult patients with low-risk penicillin allergies were offered direct delabeling or a single-dose oral penicillin challenge.
- The primary endpoint was the proportion of patients successfully delabeled.
- Secondary endpoints included antibiotic utilization pre- and post-delabeling.
Main Results:
- 355 out of 1225 patients with penicillin allergies were delabeled.
- Oral penicillin challenges were safe, with 97% of patients testing negative.
- Delabeled patients showed increased narrow-spectrum penicillin use and appropriate prescribing, with reduced restricted antibiotic use.
Conclusions:
- A combined approach of direct delabeling and oral penicillin challenge effectively impacts antibiotic prescribing.
- This program improved the use of preferred antibiotics and enhanced appropriate prescribing practices.
Background:
Penicillin allergies are associated with inferior patient and antimicrobial stewardship outcomes. We implemented a whole-of-hospital program to assess the efficacy of inpatient delabeling for low-risk penicillin allergies in hospitalized inpatients.
Methods:
Patients ≥ 18 years of age with a low-risk penicillin allergy were offered a single-dose oral penicillin challenge or direct label removal based on history (direct delabeling). The primary endpoint was the proportion of patients delabeled. Key secondary endpoints were antibiotic utilization pre- (index admission) and post-delabeling (index admission and 90 days).
Results:
Between 21 January 2019 and 31 August 2019, we assessed 1791 patients reporting 2315 antibiotic allergies, 1225 with a penicillin allergy. Three hundred fifty-five patients were delabeled: 161 by direct delabeling and 194 via oral penicillin challenge. Ninety-seven percent (194/200) of patients were negative upon oral penicillin challenge. In the delabeled patients, we observed an increase in narrow-spectrum penicillin usage (adjusted odds ratio [OR], 10.51 [95% confidence interval {CI}, 5.39-20.48]), improved appropriate antibiotic prescribing (adjusted OR, 2.13 [95% CI, 1.45-3.13]), and a reduction in restricted antibiotic usage (adjusted OR, 0.38 [95% CI, .27-.54]). In the propensity score analysis, there was an increase in narrow-spectrum penicillins (OR, 10.89 [95% CI, 5.09-23.31]) and β-lactam/β-lactamase inhibitors (OR, 6.68 [95% CI, 3.94-11.35]) and a reduction in restricted antibiotic use (OR, 0.52 [95% CI, .36-.74]) and inappropriate prescriptions (relative risk ratio, 0.43 [95% CI, .26-.72]) in the delabeled group compared with the group who retained their allergy label.
Conclusions:
This health services program using a combination of direct delabeling and oral penicillin challenge resulted in significant impacts on the use of preferred antibiotics and appropriate prescribing.
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