Letter: Analysis of ‘Faecal Biomarkers for Diagnosis and Prediction of Disease Course in Treatment-Naive Patients With IBD’

Abstract

We read with interest the study by Ling Lundström et al. [1] on the use of faecal biomarkers for diagnosing and predicting disease course in treatment-naïve patients with inflammatory bowel disease (IBD). While the research provided valuable insights, several aspects warrant further consideration.

First, the study highlighted faecal calprotectin (FC) as a key marker, but concerns about its specificity remain. FC levels can also be elevated in other inflammatory conditions such as diverticulitis or coeliac disease, complicating differentiation between IBD and other gastrointestinal conditions [2, 3]. A more rigorous approach to enhance specificity, possibly through combined biomarkers or additional diagnostic tools, is needed to prevent misdiagnosis.

Moreover, while the authors suggested FC's potential in predicting disease course, the study lacked long-term follow-up to confirm its prognostic value. Although FC correlates with disease activity at specific points, its utility in predicting long-term outcomes, including relapse, remains inconsistent [4, 5]. Future studies should include longitudinal monitoring to clarify the role of FC in guiding treatment strategies over time.

The article briefly mentioned faecal lactoferrin, but a more detailed comparison with FC is needed. Recent evidence indicates that lactoferrin may better correlate with neutrophilic infiltration in IBD [6]. Additionally, newer biomarkers, such as S100A12, have shown promise and should be explored further for more comprehensive disease monitoring [7].

Another key issue was the lack of attention to confounding factors. Variables like NSAID use, infections, or diet can affect biomarker levels, potentially leading to inaccurate results if not properly controlled for [8]. The study would have benefited from addressing how to distinguish between IBD-related elevations in biomarker levels and those caused by external factors.

Additionally, while the focus on treatment-naïve patients is valid, many patients with IBD are not treatment-naïve. Treatments such as corticosteroids and biologics can significantly alter biomarker profiles, potentially complicating their diagnostic and predictive value. Future research should examine how prior treatment affects faecal biomarkers in patients newly diagnosed and those relapsing.

Finally, the economic implications of routine faecal biomarker testing were not fully explored. Although less invasive than endoscopy, frequent biomarker testing can still become costly, particularly in resource-limited settings. A thorough cost–benefit analysis would help to determine the practicality of incorporating faecal biomarkers into standard IBD care.

In summary, while this study provided important insights into faecal biomarkers for diagnosing and predicting disease course in treatment-naïve patients with IBD, further research is needed to address concerns regarding specificity, long-term utility and cost-effectiveness.

Yuxiang Chen: writing – original draft. Wenjian Hu: writing – review and editing. Fengfeng Qin: conceptualization.

The authors declare no conflicts of interest.

This article is linked to Ling Lundström et al papers. To view these articles, visit https://doi.org/10.1111/apt.18154 and https://doi.org/10.1111/apt.18369.