Table 1.

Cohort characteristics

IUS examinations	n = 345
CD patients	n = 242
Examinations in CD patients; n	n = 280
Male; n [%]	92 [38.0%]
Age at IUS; median [range], years	37 [27–52]
Disease duration at time of IUS in median years [IQR]	10 [4–19]
Montreal classification in CD patients
A1 [<16 years]	45 [18.6%]
A2 [17–40 years]	164 [67.8%]
A3 [>40 years]	33 [13.6%]
L1 [ileum]	106 [43.8%]
L2 [colon]	36 [14.9%]
L3 [ileocolonic]	99 [40.9%]
+ L4 [upper GI]	1 [5.8%]
L4 only	1 [0.4%]
B1 [non stricturing, non-penetrating]	138 [57.0%]
B2 [stricturing]	58 [24.0%]
B3 [penetrating]	46 [19.0%]
P [perianal disease]	66 [27.3%]
Previous surgical resection at time of IUS
ICR and ileal re-resections	113 [40.4%]
[partial] colonic resection	31 [11.1%]
Medication use at time of IUS	112 [40.0%]
Biologics [infliximab, adalimumab, vedolizumab, ustekinumab]	64 [22.9%]
Immunomodulators [thiopurines/methotrexate]	48 [17.1%]
Corticosteroids [oral/topical] 5-ASA [oral/topical]	10 [3.6%]
UC patients	n = 59
IUS examinations in UC patients; n	65
Male; n [%]	22 [37.3%]
Age at IUS; median [range], years	40 [27–51]
Disease duration at time of IUS in median years [IQR]	7 [5–13]
Disease extent
E1 [proctitis]	5 [8.5%]
E2 [left-sided]	19 [32.2%]
E3 [pancolitis]	35 [59.3%]
Previous surgical resection at IUS	0 [0%]
Medication use at time of IUS	25 [38.5%]
Biologics	17 [26.2%]
Immunomodulators	13 [20.0%]
Corticosteroids [oral/topical]	38 [58.5%]
5-ASA   Tofacitinib	3 [4.6%]

CD, Crohn’s disease; IUS, intestinal ultrasound; IQR, interquartile range; GI, gastrointestinal; 5-ASA, 5-aminosalicylate; UC, ulcerative colitis; ICR, ileocaecal resection.