Evaluation of fidaxomicin use in patients with a macrolide allergy/intolerance.

Abstract

Fidaxomicin, a macrolide antibiotic, has been shown to be non-inferior to oral vancomycin for the treatment of Clostridioides difficile infection (CDI) and is associated with lower recurrence rates.1 The 2021 update to the IDSA and Society of Healthcare Epidemiology of America CDI guidelines recommend fidaxomicin 200 mg orally twice daily for 10 days as a first-line treatment option for non-severe and severe CDI.2 However, the use of fidaxomicin in patients with a macrolide allergy may pose a challenge for clinicians given the potential structural similarities and risk for cross-reactivity.3 The product labelling also has a warning to use fidaxomicin with caution in patients with a history of a macrolide allergy because they may be at an increased risk for hypersensitivity reactions.4 While macrolide allergies are relatively rare, with an incidence of 0.4%–3%,3,5 clinicians may encounter this scenario in clinical practice. However, limited published reports are currently available to describe potential cross-reactivity and hypersensitivity reactions between fidaxomicin and other macrolides.3,6,7 Herein, we describe a small cohort of patients with a labelled macrolide allergy/intolerance who received fidaxomicin.