CDI
Image credit: Unsplash
A recent study aims to compare the effectiveness of vancomycin and metronidazole in achieving event-free survival (EFS) after an initial Clostridioides difficile (C difficile) infection (CDI), using data from a multicenter cohort study conducted in Germany. The findings support recent guideline updates, emphasizing that vancomycin is more effective than metronidazole across all infection severity levels.1
The study included 489 patients with a first episode of CDI between August 2017 and September 2020. Of these, 118 (24%) were treated with metronidazole and 371 (76%) with vancomycin. Among patients receiving metronidazole, 78 of 118 (66.1%) achieved EFS, compared to 247 of 371 (66.6%) in the vancomycin group. EFS was defined as a response to treatment within ten days, with no recurrence or death within 90 days post-treatment.1
The IBIS multicenter cohort study included patients with a first episode of CDI between August 2017 and September 2020. EFS was the primary endpoint, defined as a response to treatment with metronidazole or vancomycin within ten days, with no recurrence or death from any cause up to 90 days post-treatment.1
Main Takeaways
1. Vancomycin is more effective than metronidazol for achieving event-free survival in CDI, according to a German multicenter study.
2. The study supports updated guidelines recommending vancomycin as the preferred treatment for CDI across all infection severity levels.
3. Reduced vancomycin susceptibility in some C difficile strains underscores the need for regular susceptibility testing and consideration of alternative treatments, such as fidaxomicin.
In the non-severe infection subgroup, 74 of 293 patients (25.3%) received metronidazole, and 219 of 293 (74.7%) received vancomycin. Of these, 33 of 74 (44.6%) in the metronidazole group and 150 of 219 (68.5%) in the vancomycin group achieved EFS. The Cox proportional hazards model indicated that vancomycin was associated with better EFS outcomes compared to metronidazole, with hazard ratios of .46 for all severity levels (95% CI .33-.65), .39 for non-severe infections (95% CI .24-.60), and .52 for severe infections (95% CI .28-.95).1
The study utilized a Cox proportional hazards model with inverse probability of treatment weighting to assess treatment effectiveness and analyzed data separately for severe and non-severe infections.1
A related study published in March further supports these findings by examining the impact of CDI treatment on graft-versus-host disease (GVHD) and overall survival in allo-HCT patients. It notes that vancomycin, compared to metronidazole, is associated with lower treatment failure rates and improved outcomes, including reduced rates of GVHD and gastrointestinal GVHD (GI-GVHD). This reinforces the recommendation to use vancomycin or other more effective agents, such as fidaxomicin, as the first-line treatment for CDI.2
In summary, both studies highlight the superior efficacy of vancomycin over metronidazole in treating CDI, with implications for better patient outcomes and fewer complications.
On the contrary, recent research highlights a concerning trend of reduced vancomycin susceptibility in C difficile isolates, impacting patient outcomes negatively. Approximately 34% of isolates showed diminished susceptibility, notably the Ribotype 027 strain. Patients with these less susceptible strains experienced lower rates of sustained clinical response (SCR) and initial cure compared to those with vancomycin-susceptible strains. Specifically, 76% of patients with reduced susceptibility achieved 30-day SCR versus 86% with susceptible strains, and 89% versus 96% for 14-day initial cure.3
The study, conducted from 2016 to 2021, underscores the need for vancomycin susceptibility testing and strain typing in managing C difficile infections. Ongoing surveillance and exploration of patient-specific factors influencing reduced susceptibility to guide treatment strategies amidst rising antimicrobial resistance.3
In conclusion, the German multicenter study confirms that vancomycin is more effective than metronidazole in achieving event-free survival for C difficile infections across all infection severities. Despite these findings, reduced vancomycin susceptibility in some C difficile strains highlights the need for regular susceptibility testing and the consideration of alternative treatments, such as fidaxomicin, to address antimicrobial resistance issues.
References
-
Conrad J, Giesbrecht K, Cruz Aguilar R, et al. Comparative effectiveness of vancomycin and metronidazole on event-free survival after initial infection in patients with Clostridioides difficile – a German multicentre cohort study (IBIS). Clin Microbiol Infect. Published online August 8, 2024. Accessed August 22, 2024. doi: 10.1016/j.cmi.2024.08.003
-
Piekarska A, Sadowska-Klasa A, Mensah-Glanowska P, et al. Effective treatment of Clostridioides difficile infection improves survival and affects graft-versus-host disease: a multicenter study by the Polish Adult Leukemia Group. Sci Rep 14, 5947 (2024). Accessed August 22, 2024. https://doi.org/10.1038/s41598-024-56336-3
-
Eubank T, Dureja C, Garey K, et. al. Reduced Vancomycin Susceptibility in Clostridioides difficile Is Associated With Lower Rates of Initial Cure and Sustained Clinical Response. Clinical Infectious Diseases. February 21, 2024. Accessed August 22, 2024. doi: https://doi.org/10.1093/cid/ciae087
