← Issue №4/ week of Jul 26, 2026/IBD

"The role of red cell distribution width in inflammatory bowel disease evaluation: a comprehensive systematic review and meta-analysis".

From GI Signals issue №4: what this paper found, what it changes, and where it sits against the current standard of care, reviewed by Simon Mathews, MD.

IBD meta analysis · Jul 27, 2026 · BMC Gastro · IF 2.5

"The role of red cell distribution width in inflammatory bowel disease evaluation: a comprehensive systematic review and meta-analysis".

New evidencemeta-analysissystematic reviewbiomarkerCrohn's disease
Clinical takeawayConsider RDW as an adjunctive marker for IBD activity, especially in Crohn's disease, but do not replace CRP or fecal calprotectin with RDW alone. RDW's utility in UC remains less clear.
What it foundRDW >14% differentiates active Crohn's disease from remission with 86% sensitivity and 78% specificity (AUC 0.83). RDW levels were also significantly higher in active Crohn's disease compared to active ulcerative colitis (MD = 0.59, p < 0.005).
ContextConfirms RDW's association with IBD activity but does not establish superiority over existing markers like CRP or fecal calprotectin. RDW's role in UC requires further investigation.
Measured against the standard of care· AGA Clinical Practice Update on Inpatient Management of Adults With IBD (Gastroenterology 2026) / ACG UC Guideline Update 2025 / AGA Living Guideline, Moderate-to-Severe UC 2024 (panel review March 2026)

Decision at stakeusing biomarkers to assess disease activity in ulcerative colitis

No single passage of this standard matched the paper closely enough to quote, so none is shown. The standard is cited above.

Our full summary of this standard

Outpatient positioning is unchanged from the ACG 2025 UC guideline and the AGA living guideline for moderate-to-severe UC. Confirm UC with endoscopy showing continuous colonic inflammation from the rectum plus histology, after excluding infection with two-step C. difficile testing. Treat mild-moderate disease with 5-ASA chosen by route and extent: suppository for proctitis, enema for left-sided disease, oral plus rectal for extensive disease. If 5-ASA fails, treat as moderate-to-severe rather than stepping up gradually. Position advanced therapy by efficacy tier, not by an anti-TNF-first rule. Advanced-therapy-naive, higher efficacy: infliximab, vedolizumab, ozanimod, etrasimod, upadacitinib, risankizumab, guselkumab. Intermediate: golimumab, ustekinumab, tofacitinib, filgotinib, mirikizumab. Lower: adalimumab. Previously TNF-exposed, higher efficacy: tofacitinib, upadacitinib, ustekinumab. Lower: adalimumab, vedolizumab, ozanimod, etrasimod. After anti-TNF primary non-response, switch mechanism rather than cycling within the class. Treat to target (STRIDE-II): endoscopic improvement, Mayo endoscopic subscore 0-1. Begin CRC surveillance 8-10 years after diagnosis for extensive or left-sided disease; isolated proctitis follows average-risk screening. Inpatient care now follows the 2026 AGA Clinical Practice Update (13 best-practice statements). Admit for severe symptoms refractory to outpatient therapy, suspected complications (obstruction, abscess, toxic megacolon) or significant malnutrition, and identify acute severe UC by Truelove-Witts. Give every patient admitted with diarrhea two-step C. difficile testing. Test for CMV, with early endoscopy, if symptoms worsen, the patient is systemically toxic or disease is steroid-refractory. Give routine VTE prophylaxis with LMWH or fondaparinux unless contraindicated, and individualize post-discharge extension. Give IV methylprednisolone 60 mg/day or equivalent; the AGA living guideline says 40-60 mg/day, and higher doses add no benefit. Do not give adjunctive antibiotics without infection. Involve surgery early. Assess response by day 3 (72 h) using stool frequency and CRP (Oxford criteria); do not continue IV steroids beyond about 7 days without response. Rescue steroid non-responders with infliximab (accelerated or intensified dosing in selected patients with high inflammatory burden or protein-losing colopathy), cyclosporine, or a JAK inhibitor at standard or intensified dosing, or with colectomy. Before discharge, the response should be stable and a transition plan should be in place.

AGA Clinical Practice Update on Inpatient Management of Adults With IBD (Gastroenterology 2026) / ACG UC Guideline Update 2025 / AGA Living Guideline, Moderate-to-Severe UC 2024 (panel review March 2026) · reviewed 2026-10-11 ↗
Khalil Y … Abdelsamad A · BMC Gastroenterology · IF 2.5 · PubMed ↗Permalink
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