Impact of fecal occult blood on obscure gastrointestinal bleeding: Observational study

Table 1 Baseline of characteristics of the study patients (n = 202) n (%)

Characteristic
Age (yr)1	63.6 ± 14.0
Gender (Male/Female)	118 (58)/84 (42)
Indications of CE
Previous overt OGIB	96 (48)
Occult OGIB	106 (52)
FOBT
Positive FOBT	100 (50)
Negative FOBT	102 (50)
The time discrepancy between the FOBT and CE	8.5 (0-156) d
CE findings of the small bowel2
Ulcer	13 (6)
Erosion	37 (18)
Angiectasia	22 (11)
Tumor	8 (4)
Active bleeding	19 (9)
Daily using drugs
NSAIDs	18 (9)
Aspirin	44 (22)
% of capsule obtained cecum image	83%
Blood test1
Hemoglobin (g/dL)	10.6 ± 2.3
BUN (mg/dL)	17.5 ± 10.6
Creatinine (mg/dL)	1.25 ± 1.69
Serum iron (μg/dL)	65.7 ± 56.2
Ferritin (ng/mL)	95.4 ± 20.1

¹Mean ± SD;

²Number of patients. CE: Capsule endoscopy; OGIB: Obscure gastrointestinal bleeding; NSAIDs: Non-steroidal anti-inflammatory drugs; BUN: Blood urea nitrogen.

Table 2 Comparison of the clinical data between the study patients with positive and negative fecal occult blood test n (%)

	Positive FOBT(n = 100)	Negative FOBT(n = 102)	P value
Age (yr)1	65.3 ± 14.1	61.9 ± 13.8	0.08
Daily using drugs2
NSAIDs	7 (7)	11 (11)	0.35
Aspirin	24 (24)	20 (20)	0.45
Warfarin	14 (14)	11 (11)	0.49
Blood test1
Hemoglobin (g/dL)	10.4 ± 2.5	10.9 ± 2.1	0.17
BUN (mg/dL)	19.0 ± 12.1	16.2 ± 8.9	0.07
Creatinine (mg/dL)	1.46 ± 1.88	1.04 ± 1.48	0.08
Serum iron (μg/dL)	67.9 ± 57.1	63.5 ± 55.4	0.62
Ferritin (ng/mL)	88.8 ± 22.0	90.6 ± 17.7	0.58

¹Mean ± SD;

²Number of patients. FOBT: Fecal occult blood test; NSAIDs: Non-steroidal anti-inflammatory drugs; BUN: Blood urea nitrogen.

Table 3 Prevalence of small bowel diseases detected by capsule endoscopy in patients with positive and negative fecal occult blood test n (%)

	Positive FOBT(n = 100)	Negative FOBT(n = 102)	P value
Any small bowel lesions (n = 72)	46 (46)	25 (25)	0.002
Ulcer (n = 13)	11 (11)	2 (2)	0.009
Erosion (n = 37)	21 (21)	16 (16)	0.330
Angiectasia (n = 22)	14 (14)	8 (8)	0.160
Tumor (n = 8)	5 (5)	3 (3)	0.450
Active bleeding (n = 19)	15 (15)	4 (4)	0.007

FOBT: Fecal occult blood test.

Table 4 Prevalence of each small bowel disease detected by capsule endoscopy in patients with occult obscure gastrointestinal bleeding n (%)

	Positive FOBT patients with occult OGIB(n = 55)	Negative FOBT patients with occult OGIB(n = 51)	P value
Ulcer	4 (7)	0	0.049
Erosion	11 (20)	7 (14)	0.390
Angiectasia	9 (16)	4 (8)	0.180
Tumor	4 (7)	0	0.049
Active bleeding	7 (13)	0	0.008

FOBT; Fecal occult blood test; OGIB: Obscure gastrointestinal bleeding.

Table 5 Univariate analysis of predictive factors for small bowel diseases in patients with obscure gastrointestinal bleeding

Factor	OR	95%CI	P value
Age (yr)
> 64	1.2	0.67-2.2	0.52
≤ 64	1
Sex
Male	1
Female	1.1	0.61-2.0	0.75
FOBT
Positive	2.5	1.4-4.5	0.002
Negative	1
OGIB
Overt	1.4	0.78-2.5	0.27
Occult	1
Hemoglobin (g/dL)
≤ 10.6	1.5	0.81-2.6	0.21
> 10.6	1
Medication
NSAIDs	0.67	0.23-2.0	0.47
Aspirin and/or other anticoagulants	0.83	0.45-1.6	0.57

FOBT: Fecal occult blood test; OGIB: Obscure gastrointestinal bleeding; NSAIDs: Non-steroidal anti-inflammatory drugs; CI: Confidence interval.

Table 6 Multivariate analysis of predictive factors for small bowel diseases in patients with obscure gastrointestinal bleeding

Factor	OR	95%CI	P value
Positive FOBT	2.5	1.4-4.6	0.003
Overt OGIB	1.4	0.78-2.6	0.25
Hemoglobin level ≤ 10.6 g/dL	1.2	0.68-2.3	0.48

FOBT: Fecal occult blood test; OGIB: Obscure gastrointestinal bleeding; CI: confidence interval.