Laboratory test variables useful for distinguishing upper from lower gastrointestinal bleeding

Table 1 Diseases that caused upper gastrointestinal bleeding

Diseases	No. of patients
Gastric ulcer	31
Gastric cancer	28
Duodenal ulcer	7
Acute gastric mucosal lesion	4
Esophageal ulcer	2
Esophageal varix	2
Esophagitis	1
Gastric invasion of pancreatic cancer	1
Total	76

Table 2 Diseases that caused lower gastrointestinal bleeding

Diseases	No. of patients
Colorectal cancer	47
Ulcerative colitis	6
Colitis	4
Ulcer	4
Diverticulum	1
Hemorrhoid	1
Proctitis	1
Unknown	1
Total	65

Table 3 Comparison of variables between patients with upper and lower gastrointestinal bleeding

Characteristics	Upper group	Lower group	P value
Age (yr)	70.4 ± 12.3	71.5 ± 11.9	0.6016
WBC count (102/μL)	8.792 ± 11.751	7.033 ± 3.438	0.2773
Hb (g/dL)	10.1 ± 3.2	11.3 ± 2.6	0.0230
CRP (mg/dL)	1.4 ± 1.5	2.0 ± 4.0	0.3220
Plt (104/μL)	27.4 ± 11.2	26.5 ± 11.1	0.6633
TP (g/dL)	6.0 ± 0.85	6.7 ± 0.8	0.0002
Alb (g/dL)	3.4 ± 0.6	3.5 ± 0.9	0.5958
T-Bil (mg/dL)	0.69 ± 0.57	0.70 ± 0.38	0.9236
ALP (IU/L)	236 ± 138	306 ± 218	0.2074
AST (IU/L)	25.3 ± 20.7	22.3 ± 10.0	0.3515
ALT (IU/L)	20.2 ± 18.2	16.9 ± 10.9	0.2422
γ-GTP (IU/L)	56.3 ± 88.1	32.1 ± 20.8	0.319
LDH (IU/L)	189.2 ± 51.7	243.7 ± 114.3	0.009
UA (mg/dL)	5.3 ± 2.0	5.8 ± 1.5	0.3541
BUN (mg/dL)	21.1 ± 15.8	14.1 ± 5.5	0.0065
Cre (mg/dL)	0.93 ± 0.35	0.84 ± 0.25	0.1153
T-Chol (mg/dL)	158.4 ± 45.8	175.4 ± 41.9	0.1966
TG (mg/dL)	100.7 ± 49.6	127.0 ± 79.7	0.4095
HDL (mg/dL)	45.4 ± 10.0	55.7 ± 18.2	0.1404
LDL (mg/dL)	90.6 ± 32.2	116.9 ± 40.7	0.1094
BS (mg/dL)	132.8 ± 57.5	117 ± 26.9	0.1979
HbA1c (%)	5.8 ± 0.8	6.6 ± 0.7	0.0379
BMI	21.6 ± 4.2	21.4 ± 3.4	0.9126
CEA (ng/mL)	13.6 ± 25.9	217.5 ± 753.5	0.2884
CA19-9 (U/mL)	784 ± 3.017	159.9 ± 450.5	0.3429

Plt: Platelet; TP: Total protein; Alb: Albumin; T-Bil: Total bilirubin; ALP: Alkaline phosphatase; ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; BG: Blood glucose; BMI: Body mass index; BUN: Blood urea nitrogen; CA19-9: Carbohydrate antigen 19-9; CEA: Carcinoembryonic antigen; Cre: Creatinine; CRP: C-reactive protein; γ-GTP: γ-glutamyl transpeptidase; Hb: Hemoglobin; HbA1c: Hemoglobin A1c; HDL: High-density lipoprotein cholesterol; LDH: Lactate dehydrogenase; LDL: Low-density lipoprotein cholesterol; T-Chol: Total cholesterol; TG: Triglyceride; UA: Uric acid; WBC: White blood cell count.

Table 4 Results of logistic regression analysis

	χ2	Odds	Odds (95%CI)	P value
Hb	0.04	1.045994	0.669624-1.717491	0.8446
TP	1.03	2.221154	0.514904-13.65946	0.3100
LDH	1.05	1.015110	0.987842-1.049002	0.3057
BUN	2.38	0.879782	0.697744-0.980732	0.1232

Hb: Hemoglobin; TP: Total protein; LDH: Lactate dehydrogenase; BUN: Blood urea nitrogen.

Table 5 Results of the likelihood ratio test

	Likelihoodχ2	P value
Hb	0.03883460	0.8438
TP	1.12378238	0.2891
LDH	1.13905685	0.2859
BUN	6.62036996	0.0101

Hb: Hemoglobin; TP: Total protein; LDH: Lactate dehydrogenase; BUN: Blood urea nitrogen.

Table 6 Results of receiver-operator characteristic analysis

	AUC	Threshold value	Sensitivity	Specificity
Hb	0.61894	8.7 (g/dL)	42.7%	80.7%
TP	0.71197	6.3 (g/dL)	62.8%	81.3%
LDH	0.71515	191 (IU/L)	64.4%	77.32%
BUN	0.61459	21 (mg/dL)	36.4%	93.0%

Hb: Hemoglobin; TP: Total protein; LDH: Lactate dehydrogenase; BUN: Blood urea nitrogen.