Coronavirus disease-2019 (COVID-19) ranges from asymptomatic to severe. Several co-morbidities are associated with worse clinical outcomes. Antibiotic use is common in COVID-19 and penicillin (PCN) allergy can impact antibiotic choice and may influence COVID-19 outcomes.
To investigate the impact of PCN allergy label on COVID-19 outcomes.
For this retrospective, cohort study, a web-based tool for population cohort research, TriNetX, was used to identify adult COVID-19 patients with and without PCN allergy label. The two cohorts were matched using 1:1 propensity score matching (PSM) for baseline demographics and conditions associated with risk of severe COVID-19. The 30-day risks of hospitalization, acute respiratory failure, intensive care unit (ICU) requirement, mechanical ventilation requirement, and mortality were then compared between the two groups. As bacterial infection can drive alternative antibiotic regimens, additional analyses focused on patients without bacterial infection.
After PSM, each cohort consisted of 13,183 patients. COVID-19 patients with PCN allergy had higher risks of hospitalization (RR, 1.46; 95% CI, 1.41 to 1.52) acute respiratory failure (RR, 1.25; 95% CI, 1.19 to 1.31), ICU requirement (RR, 1.20; 95% CI, 1.08 to 1.34), and mechanical ventilation (RR, 1.17; 95% CI 1.03 to 1.32) when compared to patients without PCN allergy; however, there was no mortality difference (RR, 1.09; 95% CI 0.96 to 1.23). Although the bacterial infection risk was higher in PCN allergic COVID-19 patients, exclusion of patients with bacterial infections yielded similar results.
PCN allergic patients have higher risk of worse COVID-19 outcomes and should be considered for risk mitigation strategies.

Copyright © 2021. Published by Elsevier Inc.