Role of intestinal ultrasound in ulcerative colitis: A systematic review

Table 11 Summary of studies on intestinal ultrasound in pediatric inflammatory bowel disease

Ref.	Study type	Number of patients	Follow-up duration	Gold standard	Comparator	Results
Borthne et al[48]	Prospective	43 children with suspected IBD	3 wk	Endoscopy	Endoscopy	Sensitivity and accuracy of IUS compared to endoscopy: 93.3%
Bremner et al[49]	Prospective	12 UC (25 CD, 1 indeterminate colitis, 6 normal)	Cross-sectional	ileo-colonoscopy	Ileo-colonoscopy	Colonic BWT > 2.9: Sensitivity for moderate/severe disease: 48%, specificity: 93%, PPV: 83%; ileal BWT > 2.5 mm: Sensitivity for moderate/severe disease: 75%, specificity: 92%, PPV: 88%
Haber et al[47]	Prospective	21 UC pediatrics (26 CD, controls)	Cross-sectional	Ileo-colonoscopy	Ileo-colonoscopy	Sensitivity and specificity of IUS as compared to endoscopy: 77% and 83%, respectively
Ziech et al[8]	Prospective	28 suspected IBD pediatrics	Cross-sectional	Ileocolonoscopy and endoscopy	MR colonography	Sensitivity IUS: 55%; MR colonography: 57%. Specificity IUS: 100%; MR colonography: 75%; cannot effectively differentiate UC and CD unless terminal ileum is involved
Barber et al[71]	Retrospective	53 children	Cross-sectional	Combined consensus score based imaging and clinical scores	MRE	Clinical correlation of IUS score (0.657) > MRE score (0.598); agreement for IUS scoring: Coefficient 0.95
Chavannes et al[72]	Cross-sectional, single centre	33 children with suspected IBD (1 UC)	Cross-sectional	Ileo-colonoscopy	Ileo-colonoscopy	Colonic BWT > 1.9 mm: AUC 0.743, sensitivity: 64%. specificity: 76% to detect inflamed bowel. Agreement with colonoscopy: Prediction of IBD: 69.7%, kappa = 0.52; distribution of disease: 45.5%, kappa = 0.48
Dell'Era et al[7]	Retrospective	113 suspected pediatric IBD	1 year	Ileo-colonoscopy and 1 year follow-up	Ileo-colonoscopy	IUS bowel pattern, mesenteric hypertrophy, and BWT > 3; all 3 sensitivity: 57.5%; specificity: 100%
Scarallo et al[35]	Single centre, retrospective	25 acute severe UC patients	Cross-sectional	NA	PUCAI > 45 at day 3; PUCAI > 65 day 5	At day 3 BWT > 3.4 mm and loss of BWS are independent predictors of steroid failure; BWT > 3.4 mm 92% sensitivity and 52% specificity for steroid resistance; PUCAI > 45 at day 3: 80.6% sensitivity and 45.5% specificity; PUCAI > 65 at day 5: 33.3% sensitivity and 90% specificity
van Wassenaer et al[68]	Prospective cross-sectional	22 UC	Cross-sectional	Ileo-colonoscopy	Physicians vs radiologists	Moderate inter-observer agreement for disease activity in terminal ileum (kappa = 0.58), descending colon (kappa = 0.52), and transverse colon (kappa = 0.49) between radiologists (AUC: 0.67-0.79) and gastroenterologists (AUC: 0.71-0.81)
Hudson et al[69]	Cross-sectional study	35 CD,15 UC,4 IBD	Cross-sectional	SES-CD, Mayo endoscopic score	MRE and endoscopy	High patient and caregiver satisfaction. Preferred over MRE and colonoscopy. No concern about IUS findings in those with co-existing anxiety
van Wassenaer et al[64]	Prospective cross-sectional	35 UC (pediatric)	Cross-sectional	Mayo endoscopic score	Endoscopy	UC-IUS score better than Civitelli index for both sensitivity (88-100% vs 65%-80%) and specificity (84%-87% vs 89%-93%) (MES ≥ 2); higher AUC in ascending colon (0.82 vs 0.76) and transverse colon (0.88 vs 0.77). No difference in descending colon (both 0.84)
Mohamed et al[74]	Prospective	40 IBD	Cross-sectional	Clinical and fecal calprotectin	Clinical activity	Combined gray scale ultrasound, color Doppler, and shear wave elastography increase accuracy (92%) with 100% accuracy
Otani et al[73]	Retrospective	40 UC	Cross-sectional	Colonoscopy and fecal calprotectin	Fecal calprotectin	Accuracy of sum of adjusted bowel wall thickness was higher than fecal calprotectin for detecting moderate colonic inflammation (Mayo endoscopic score 2)
Spyropoulou et al[70]	Prospective	32 UC	cross-sectional	Colonoscopy	Colon capsule endoscopy, fecal calprotectin	Sensitivity, specificity, PPV, and NPV of US are 85%, 92%, 94%, and 79%, respectively. Noninvasive approach combining CCE, FCP, and IUS better tolerated than colonoscopic monitoring

CD: Crohn’s disease; UC: Ulcerative colitis; TI: Terminal ileum; IUS: Intestinal ultrasound; HRUS: High resolution ultrasound; MRI: Magnetic resonance imaging; MRE: Magnetic resonance enterography; BWT: Bowel wall thickness; PCD: Pediatric Crohn’s disease; UC-IUS: Ulcerative colitis intestinal ultrasound score; PCDAI: Paediatric Crohn Disease Activity; CCE: Colon capsule endoscopy; FCP: Fecal calprotectin; AUC: Area under curve; IBD: Inflammatory bowel disease; PUCAI: Pediatric ulcerative colitis activity index, PPV: Positive predictive value; NPV: Negative predictive value.