Long-Term Outcomes Associated With β-Lactam Allergies

Area of Science:

• Infectious Diseases
• Clinical Pharmacology
• Health Services Research

Background:

• Beta-lactam (BL) allergies are common but often misdiagnosed, posing risks for adverse drug events and antibiotic resistance.
• Understanding the long-term health outcomes for patients with BL allergies is limited.

Purpose of the Study:

• To evaluate the long-term clinical outcomes, including mortality and antibiotic-resistant infections, in patients with documented beta-lactam allergies.

Main Methods:

• A longitudinal retrospective cohort study analyzed electronic health records of over 20,000 patients with sepsis, pneumonia, or UTI from 2007-2008.
• Patients were followed until 2018, with outcomes including all-cause mortality, methicillin-resistant Staphylococcus aureus (MRSA), Clostridium difficile, vancomycin-resistant Enterococcus (VRE), and acute kidney injury (AKI).
• Generalized estimating equations were used to compare outcomes between patients with and without documented BL allergies.

Main Results:

• Documented BL allergies were not significantly associated with increased all-cause mortality (OR, 1.02).
• BL allergies were associated with higher odds of MRSA (OR, 1.44) and VRE (OR, 1.18) infections, and pooled antibiotic-resistant infections (OR, 1.33).
• No significant association was found between BL allergies and Clostridium difficile infection or acute kidney injury.

Conclusions:

• Documented beta-lactam allergies are not linked to long-term mortality but are associated with increased risk of antibiotic-resistant infections.
• Healthcare systems should prioritize accurate allergy documentation and minimize unnecessary avoidance of beta-lactam antibiotics.