Table 2.

Performance of intestinal ultrasound in the assessment of disease activity in inflammatory bowel disease

Performance of IUS	Sensitivity %[95%CI]			Specificity %[95%CI]			PPV %[95%CI]			NPV %[95%CI]
	Total	UC	CD	Total	UC	CD	Total	UC	CD	Total	UC	CD
vs EAI
Overall	66.7 [41,86]	50.0 [17,83]	80.0 [44,97]	97.0[83,100]	100 [81,100]	91.7[60,100]	92.3[62,100]	100[40,100]	88.9 [51,99]	84.2 [68,93]	84 [63,95]	84.6 [54,97]
Per parameters
BWT	72.2 [46,89]	33.3 [2,88]	80.0 [44,97]	75.8 [57,88]	65.4 [44,82]	75.0 [43,93]	61.9 [39,81]	10.0 [1,46]	72.7 [39,93]	83.3 [65,94]	89.5 [66,98]	81.8 [48,97]
LWS	61.1 [36,82]	33.3 [2,88]	70.0 [35,92]	93.9 [78,99]	84.6 [64,95]	91.7[60,100]	84.6 [54,97]	20.0 [1,70]	87.5 [47,99]	81.6 [65,92]	91.7 [72,99]	78.6 [49,94]
MFP	50.0 [27,73]	33.3 [2,88]	60.0 [27,86]	100 [87,100]	92.3 [73,99]	100 [70,100]	100 [63,100]	33.3 [2,88]	100[52,100]	78.6 [63,89]	92.3 [73,99]	75.0 [47,92]
IV	50.0 [27,73]	33.3 [2,88]	60.0 [27,86]	97.0[83,100]	92.3 [73,99]	91.7[60,100]	90.0[54,100]	33.3 [2,88]	85.7 [42,99]	78.0 [62,89]	92.3 [73,99]	73.3 [45,91]
Per-bowel segment
Terminal ileum	40.0 [14,73]	0.0 [0,95]	44.4 [15,77]	97.6[86,100]	96.4[80,100]	100 [72,100]	80.0 [30,99]	0.0 [0,95]	100[40,100]	87.0 [73,95]	96.4[80,100]	72.2 [46,89]
Right colon	70.0 [35,92]	0.0 [0,95]	77.8 [40,96]	100 [89,100]	100 [85,100]	100 [72,100]	100 [56,100]	-	100[56,100]	93.2 [80,98]	96.6[80,100]	86.7 [58,98]
Transverse colon	100 [60,100]	100[31,100]	100[46,100]	95.3 [83,99]	100 [84,100]	88.2 [62,98]	80.0 [44,97]	100[31,100]	71.4 [30,95]	100 [89,100]	100 [84,100]	100[75,100]
Left colon	61.1 [36,82]	45.5 [18,75]	85.7 [42,99]	100 [87,100]	100 [78,100]	100 [75,100]	100 [68,100]	100[46,100]	100[52,100]	82.5 [67,92]	75.0 [53,89]	93.8[68,100]
Rectum	42.1 [21,66]	36.4 [12,68]	50.0 [17,83]	93.8 [78,99]	94.4[71,100]	92.9[64,100]	80.0 [44,97]	80.0 [30,99]	80.0 [30,99]	73.2 [57,85]	70.8 [49,87]	76.5 [50,92]
Correlation	r=0.698 (P<0.01)	r=0.648 (P<0.01)	r=0.726 (P<0.01)
vs CAI
Overall	70.0 [35,92]	33.3 [2,88]	85.7 [42,99]	85.4 [70,94]	88.5 [69,97]	80.0 [51,95]	53.8 [26,80]	25.0 [1,78]	66.7 [31,91]	92.1 [78,98]	92.0 [73,99]	92.3[62,100]
Correlation	r=0.504 (P<0.01)	r=0.192 (P=0.317)	r=0.623 (P=0.002)
vs biomarkers
Faecal calprotectin	r=0.489 (P=0.001)	r=0.461 (P=0.018)	r=0.511 (P=0.025)
C-reactive protein	r=0.604 (P<0.01)	r=0.475 (P=0.009)	r=0.647 (P=0.001)
vs CT/MRI
Correlation	r=0.661 (P=0.007)	-	r=0.745 (P=0.002)

IUS=intestinal ultrasound, PPV=positive predictive value, NPV=negative predictive value, CI=confidence interval, UC=ulcerative colitis, CD=Crohn’s disease, vs=versus, EAI=endoscopic activity index, BWT=bowel wall thickening, LWS=loss of wall stratification, MFP=mesenteric fatty proliferation, IV=increased vascularity, r=Pearson’s correlation coefficient, CAI=clinical activity index, CT=computed tomography, MRI=magnetic resonance imaging