Antimicrobial resistance is not increasing in subsequent cases of ischaemic foot infections, a single-centre cohort from 2012 to 2021

We read with keen interest the article titled “Antimicrobial resistance is not increasing in subsequent cases of ischaemic foot infections: a single-centre cohort from 2012 to 2021” by Salm et al., published in your esteemed journal.¹ This study addresses a significant aspect of infectious disease management by examining the link between antibiotic therapy and antimicrobial resistance (AMR) in recurring episodes of ischemic foot infections (IFI). However, several methodological considerations and limitations warrant further discussion to enhance the study's impact and validity:

Firstly, the study's statistical power is intrinsically tied to the sample size. The relatively small sample size used in this research may undermine the robustness of the findings, leading to an increased margin of error and reduced reliability of the conclusions.² Cohort studies require a sufficiently large sample to ensure the precision and generalizability of the results.

Secondly, retrospective cohort studies, such as this one, are prone to various biases. Incomplete recording of medical and laboratory data in patient files poses a significant risk. Moreover, the study did not adjust for critical confounding variables such as patient comorbidities and previous antimicrobial use, which could significantly impact the outcomes. A more rigorous adjustment for these factors is essential to accurately assess the relationship between antibiotic therapy and AMR.

Another notable limitation is the short follow-up period for monitoring antimicrobial resistance, which was confined to the duration of hospital stays. This approach fails to capture the long-term dynamics of AMR development and the recurrence of IFI post-discharge. Including follow-up data after patients are discharged would provide a more comprehensive understanding of AMR trends over time.

The findings of this study are crucial given the current global trends in AMR. However, the methodological limitations outlined above restrict the broader applicability of the results. Addressing these limitations in future research is essential to develop more effective strategies for managing IFI and combating AMR.

In conclusion, despite these limitations, the study by Salm et al. offers valuable insights into AMR patterns in IFI cases. Addressing the highlighted methodological issues would significantly bolster the robustness and applicability of the findings for future research and clinical practice. We urge the authors and the journal to consider these concerns and integrate feasible solutions in subsequent studies.

The authors declare no conflicts of interest.