AN INCREASED risk of antibiotic-resistant infections, for up to 12 years, is associated with having a β-lactam allergy, according to recent research. β-lactam allergies are established risk factors for adverse drug events and antibiotic-resistant infections during inpatient healthcare encounters. However, the long-term outcomes of patients with this allergy are not well understood, therefore, this study aimed to expand on previous UK-based studies by evaluating additional outcomes in an American cohort, focusing on secondary outcomes like acute kidney injury and other antibiotic-resistant infections.
The researchers analysed electronic health records from a regional healthcare system in western Pennsylvania, USA. It included patients with an index encounter for sepsis, pneumonia, or urinary tract infection between 2007 and 2008. Follow-up continued until death or the end of 2018. The study included 20,092 patients, with a mean age of 62.9 years, of whom 60.9% were female. Among them, 4211 (21.0%) had a documented β-lactam allergy, whilst 15,881 (79.0%) did not. The primary outcome was all-cause mortality, derived from the Social Security Death Index. Secondary outcomes included infection with methicillin-resistant Staphylococcus aureus (MRSA), Clostridium difficile, vancomycin-resistant Enterococcus (VRE), and severity and occurrence of acute kidney injury (AKI).
Analysis showed that β-lactam allergies were not significantly associated with all-cause mortality (odds ratio [OR]:1.02; 95% confidence interval [CI]: 0.96-1.09). However, β-lactam allergies were linked to higher odds of MRSA infection (OR: 1.44; 95% CI: 1.36-1.53), VRE infection (OR: 1.18; 95% CI: 1.05-1.32), and a pooled rate of antibiotic-resistant infections (OR: 1.33; 95% CI: 1.30-1.36). There was no significant association with C. difficile infection (OR: 1.04; 95% CI: 0.94-1.16), stage 2 and 3 AKI (OR:1.02; 95% CI:0.96-1.10), or stage 3 AKI (OR: 1.06; 95% CI: 0.98-1.14).
Despite the lack of significant impact on mortality, the association with increased antibiotic-resistant infections highlights the substantial long-term clinical detriment of β-lactam allergies. Therefore, health systems should prioritise accurate allergy documentation and initiatives.
Katrina Thornber, EMJ
Reference
Gray PM et al. Long-Term Outcomes Associated With β-Lactam Allergies. JAMA Netw Open. 2024;7(5):e2412313.