Fecal markers of inflammation used as surrogate markers for treatment outcome in relapsing inflammatory bowel disease

Table 1 Clinical data of the study population

	UC	CD
Number of subjects	27	11
Gender (female/male)	15/12	3/8
Age (yr, mean)	42.5 (21-66)	34.6 (21-70)
Disease duration (yr, mean)	9.3 (0-38)	5.6 (0-18)
Extent of disease:
Colon	91	8
Left side colitis	14	-
Proctitis	4	-
Ileocolitis	-	1
Prior surgery	1	1
Treatment at inclusion:
No treatment	7	4
5-ASA (topical/systemic)	19	4
Azathioprine	1	1
Prednisone (topical/systemic)	5	-
Metronidazole	-	1

¹Extensive colitis means disease extending from proximal to the splenic flexure.

Table 2 Study protocol

Procedure	Inclusion	4 wk	8 wk
Stool sample	Done	Done	Done
Clinical score	Done	Done	Done
Endoscopy and biopsy	Done1	Done2	Done3
Histopathology	Done1	Done2	Done3

¹Not done in 2 CD patients;

²Not done in 4 CD patients;

³Not done in 2 CD patients.

Table 3 FC levels (μg/g, mean, 10-90th percentile) in patients with a relapse of IBD at inclusion, and after 4 and 8 wk of treatment

	FC inclusion	FC 4 wk	FC 8 wk	P
All patients	5430 (151-14 170)	1920 (61-4150)	1720 (38-3390)	< 0.011
UC	5600 (210-14 170)	1730 (61-2620)	1820 (40-3390)	< 0.011
CD	5010 (151-9180)	2440 (124-7910)	1460 (36-5030)	= NS1

¹Friedmans Test for 3 variables.

Table 4 Correlation between fecal FC, MPO and EPX at inclusion, and after 4 and 8 wk of treatment in patients with UC and CD

Patients	Fecal marker	Inclusion	4 wk	8 wk
All	FC and MPO	R = 0.884, P < 0.01	R = 0.941, P < 0.01	R = 0.924, P < 0.01
All	FC and EPX	R = 0.592, P < 0.01	R = 0.724, P < 0.01	R = 0.642, P < 0.01
UC	FC and MPO	R = 0.868, P < 0.01	R = 0.927, P < 0.01	R = 0.940, P < 0.01
UC	FC and EPX	R = 0.556, P < 0.01	R = 0.762, P < 0.01	R = 0.602, P < 0.01
CD	FC and MPO	R = 0.936, P < 0.01	R = 0.818, P < 0.01	R = 0.903, P < 0.01
CD	FC and EPX	R = 0.654, P < 0.05	R = 0.636, P < 0.05	R = 0.854, P < 0.01

All: n = 38; UC: n = 27; CD: n = 11.

Table 5 PPV and NPV of a complete response after 8 wk of treatment in UC or CD calculated by using fecal marker levels above the 95th percentile as the cut-off value

Fecal marker	Patients	PPV (95% CI)	NPV (95% CI)
FC	All n = 371	30 (13-53)	100 (77-100)
FC	UC n = 27	38 (13-65)	100 (71-100)
FC	CD n = 101	14 (2-58)	100 (30-100)
MPO	All n = 371	23 (10-42)	100 (59-100)
MPO	UC n = 27	27 (10-50)	100 (48-100)
MPO	CD n = 101	12 (2-53)	100 (19-100)
EPX	All n = 371	22 (8-42)	90 (56-98)
EPX	UC n = 27	25 (8-49)	85 (42-98)
EPX	CD n = 101	14 (3-58)	100 (30-100)

¹One missing value. FC cut-off value 94.5 μg/g, MPO cut-off value 8.8 μg/g, EPX cut-off value 1.7 μg/g.