Antibiotic allergy labels and optimal antimicrobial stewardship

Area of Science:

• Clinical Pharmacy
• Infectious Diseases
• Health Outcomes Research

Background:

• Antimicrobial allergy labels (AAL) are frequently applied but rarely confirmed as true hypersensitivity.
• Inaccurate AAL can lead to the use of alternative, potentially less effective or more toxic, antimicrobial agents.
• Antimicrobial stewardship programs (ASPs) are well-positioned to evaluate AAL and optimize antimicrobial prescribing.

Purpose of the Study:

• To determine the prevalence of AAL in patients undergoing antimicrobial stewardship review.
• To assess the impact of AAL on antibiotic prescribing patterns, mortality, hospital length of stay, readmissions, and multidrug-resistant infections.

Main Methods:

• A retrospective analysis of adult patients referred for inpatient antimicrobial prospective audit and feedback rounds (PAFR) was conducted.
• Data from 630 patients over a 12-month period were analyzed, with outcomes followed for 36 months post-review.
• Electronic referral systems (eReferrals) were utilized for patient identification and data collection.

Main Results:

• 16% of patients reviewed had an AAL, with 13% reporting allergies to beta-lactam antibiotics.
• Patients with AAL were significantly less likely to receive guideline-recommended antimicrobial therapy (50% vs. 64%, P=0.0311).
• No significant differences were observed in mortality, hospital length of stay, readmission rates, or incidence of multidrug-resistant infections.

Conclusions:

• AAL is associated with reduced adherence to antibiotic guidelines.
• The study suggests limitations, including retrospective design and poor documentation, may have obscured associations with adverse outcomes.
• ASPs have a significant opportunity to integrate allergy assessment and de-labeling into their stewardship activities.