Prospective Study of BK Virus Infection in Patients with Inflammatory Bowel Disease

Table 1

Severity of the inflammatory bowel disease of the 53 patients included in the study according to the Harvey Bradshaw index and the Montreal classification.

(a) Patients with Crohn’s disease (𝑛=32)

Age at diagnosis	Location	Behavior	Perianal disease	Harvey bradshaw
A1: 3 (9.4%)	L1: 8 (25.0%)	B1: 13 (40.6%)	No: 21 (65.6%)	Remission: 8 (25.0%)
A2: 24 (75.0%)	L2: 8 (25.0%)	B2: 8 (25.0%)	Yes: 11 (34.4%)	Mild: 9 (28.1%)
A3: 5 (15.6%)	L3: 15 (46.8%)	B3: 11 (34.4%)		Moderate: 10 (31.2%)
	L4: 1 (3.2%)			Severe: 5 (15.7%)

(b) Patients with ulcerative colitis (𝑛=21)

Extension	Severity
E1: 5 (23.8%)	S0: 5 (23.8%)
E2: 7 (33.3%)	S1: 6 (28.6%)
E3: 9 (42.9%)	S2: 8 (38.1%)
	S3: 2 (9.5%)

A1: below 16 y; A2: 17–40 y; A3: above 40 y.
L1: ileal; L2: colonic; L3: ileocolonic; L4: isolated upper disease.
B1: nonstricturing, nonpenetrating; B2: stricturing; B3: penetrating.
E1: ulcerative proctitis. Involvement limited to the rectum.
E2: left-sided ulcerative colitis. Involvement limited to a proportion of the colorectum distal to the splenic flexure.
E3: extensive pancolitis. Involvement extends proximally to the splenic flexure.
S1: mild colitis; S2: moderate colitis; S3: severe colitis.