TOPLINE:

Soluble transferrin receptor (sTfR) levels appeared to function as an inflammation-independent marker of iron status in patients with inflammatory bowel disease (IBD) and may help distinguish true iron deficiency from inflammation-related changes in iron parameters.

METHODOLOGY:

• Researchers conducted a cross-sectional study to evaluate the utility of sTfR levels in assessing iron status in patients with IBD and identifying iron deficiency without anaemia (IDWA).
• They included 411 patients with IBD, of whom 130 had ulcerative colitis (UC; median age, 44 years; 61.24% women) and 281 had Crohn's disease (median age, 41 years; 46.98% women); they also included 178 healthy control individuals, and outcomes were compared between groups.
• IDWA was defined using ferritin thresholds (< 30 ng/mL without inflammation or < 100 ng/mL with inflammation, which was defined as having C-reactive protein [CRP] levels ≥ 3 mg/L or faecal calprotectin [FCAL] levels > 250 μg/g) and a stricter definition that also required transferrin saturation < 16%.

TAKEAWAY:

• Soluble transferrin receptor levels showed no correlation with CRP or FCAL levels in either patients with UC or those with Crohn's disease, supporting its role as an inflammation-independent marker of iron status.
• An inverse correlation was observed between sTfR and transferrin saturation in control individuals (correlation coefficient [r], -0.42; P < .001), patients with UC (r, -0.31; P < .001), and patients with Crohn's disease (r, -0.23; P < .001) as well as between sTfR and ferritin levels in control individuals (r, -0.28; P < .001), patients with UC (r, -0.21; P = .017), and patients with Crohn's disease (r, -0.15; P = .015).
• Patients with UC and IDWA had higher median sTfR levels (1.20 vs 1.05 mg/L; P = .013) than those without IDWA, whereas among patients with Crohn's disease, sTfR did not differ between those with and without IDWA.
• Among patients with Crohn's disease, median sTfR levels were higher in those with anaemia than in those without IDWA (1.16 vs 1.03 mg/L; P = .003), indicating increased iron demand associated with anaemia.

IN PRACTICE:

"Overall, sTfR should be regarded as a complementary parameter to conventional markers for iron assessment across both IBD subtypes," the authors of the study concluded.

SOURCE:

This study was led by Francisco Portela, MD, Portuguese Inflammatory Bowel Disease Study Group (GEDII), Porto, Portugal. It was published online on May 09, 2026, in Inflammatory Bowel Diseases.

LIMITATIONS:

The cross-sectional design precluded the assessment of temporal changes in iron status or inflammatory activity, limiting establishing a causal inference. The absence of a gold standard for diagnostic confirmation, lack of systematic data on endoscopic mucosal activity, and incomplete information on coexisting conditions may have restricted certainty about true iron deficiency in borderline cases.

DISCLOSURES:

This study was funded by GEDII and Vifor Pharma. Some authors reported receiving honoraria and serving as speakers for various companies including AbbVie, Pfizer, Lilly, Merck Sharp & Dohme, and Takeda.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.