Location-based prediction model for Crohn’s disease regarding a novel serological marker, anti-chitinase 3-like 1 autoantibodies

Table 1 Clinical characteristics of inflammatory bowel disease patients, n (%)

	CD (n = 266)	UC (n = 187)
Age at presentation (yr), median (IQR)	25 (19-33)	33 (23-43)
Male/female (n)	112/154	86/101
Follow-up (mo) from, median (IQR)
Diagnosis1	143 (99-214)	135 (84-213)
Time of serum collection, median (IQR)	97 (77-118)	78 (51-102)
Location/extent at diagnosis
L1	58 (21.8%)	E1 30 (16.0%)
L2	86 (32.3%)	E2 104 (55.6%)
L3	121 (45.5%)	E3 53 (28.3%)
L4 only	1 (0.4%)
Behavior at diagnosis/last follow up
B1	213 (80.1%)/117 (44.8%)
B2	32 (12.0%)/54 (20.7%)
B3	21 (7.9%)/90 (34.5%)
Perianal disease
At diagnosis/last follow-up1	48 (18.0%)/100 (38.3%)
Extraintestinal manifestations
PSC	8 (3.0%)	8 (4.3%)
Arthritis	49 (18.4%)	26 (13.9%)
Skin	35 (13.2%)	16 (8.6%)
Ocular	65 (24.4%)	12 (6.4%)
Smoking habits
Never	215 (80.8%)	167 (89.3%)
Yes	46 (17.3%)	18 (9.6%)
Previous	5 (1.9%)	2 (1.1%)
Familial IBD	12 (4.4%)	6 (3.2%)
Frequent relapse	52 (20.9%)
Cumulative exposure of medication and surgeries during follow-up
Steroid use/refractory	219 (82.3%)/30 (13.7%)	117 (63.9%)/11 (7.6%)
Azathioprine use	198 (74.4%)	70 (38.3%)
Biological use	112 (42.1%)	25 (13.4%)
Resective surgery/multiple in CD	117 (44.8%)/ 33 (12.6%)
Colectomy in UC		11 (6.0%)
Surgery due to perianal complication/multiple	61 (23.4%)/33 (12.6%)

¹261 Crohn’s disease and 183 ulcerative colitis patients had follow-up.

Location: L1: Ileal, L2: Colonic, L3: Ileocolonic, L4: Upper gastrointestinal disease. Behavior: B1: Inflammatory (non stricturing/non penetrating), B2: Stenosing (stricturing), B3: Penetrating. Disease extent: E1: Proctitis; E2: Left sided colitis; E3: Extensive colitis. Surgery: Crohn’s disease-related abdominal surgery and colectomy in ulcerative colitis. CD: Crohn’s disease; IQR: Interquartile range; UC: Ulcerative colitis; PSC: Primary sclerosing cholangitis; IBD: Inflammatory bowel disease.