Endoscopic management of intestinal strictures in Crohn’s disease: Current status and future perspectives

Table 3 Differentiating inflammatory vs fibrotic strictures[25]

	Inflammatory strictures	Fibrotic strictures	Notes/limitations
Symptoms	More acute/subacute flares; diarrhea; systemic signs; better medical response	Chronic progressive obstructive symptoms; poor medical response	Overlap is common; symptoms poorly correlate with the degree of fibrosis. Asymptomatic strictures are possible
Endoscopy	Ulcers, friability, erythema, edema; soft to touch	Pale, rigid, featureless narrowing; minimal ulcers; firm to touch	Endoscopy limited to accessible segments and mucosa only (misses submucosal/transmural fibrosis). Combination with imaging improves accuracy
Histology	Neutrophils, crypt abscesses, edema, and lymphoid aggregates	Dense collagen, smooth muscle hypertrophy, minimal inflammation	Transmural process - patchy; biopsies are superficial and underestimate fibrosis; scoring systems exist but are heterogeneous
Biomarkers	High CRP, ESR, fecal calprotectin	Often normal/low CRP/ESR/fecal calprotectin despite symptoms	No highly specific validated biomarker for fibrosis
Intestinal US (+/- elastography)	Wall thickening (> 3 mm), hypoechoic (loss of stratification), hypervascularity (high color Doppler/Limberg score), mesenteric fat stranding/lymph nodes. Lower stiffness. CEUS: Early hyperenhancement	Preserved stratification or hyperechoic, reduced vascularity. Higher stiffness on shear-wave elastography (e.g., higher kPa values)	Promising multiparametric approach (B-mode + Doppler + elastography + CEUS). Good for the terminal ileum; no radiation
CTE	Wall thickening + stratified/layered mucosal hyperenhancement, comb sign (mesenteric hypervascularity), fat stranding, lymphadenopathy, edema	Homogeneous or minimal enhancement, fatty submucosal infiltration, less mesenteric inflammation, prominent pre-stenotic dilation. Thickened wall with “featureless” appearance	Radiation exposure (avoid in young/repeat imaging). High accuracy for strictures but moderate for differentiation alone
MRE (preferred)	T2-hyperintense mural edema, stratified early hyperenhancement, DWI restriction (low ADC), comb sign, nodular luminal thickening	T2-hypointense/iso (low edema), homogeneous/delayed enhancement, less DWI restriction in pure fibrosis, pre-stenotic dilation, smooth luminal thickening, elevated magnetization transfer ratio	Best non-invasive test for characterization (sensitivity/specificity high for fibrosis)

CRP: C-reactive protein; ESR: Erythrocyte sedimentation rate; CEUS: Contrast-enhanced ultrasound; US: Ultrasound; CTE: Computed tomography enterography; MRE: Magnetic resonance enterography; ADC: Apparent diffusion coefficient; DWI: Diffusion-weighted imaging.