Combination of serum gamma-glutamyltransferase and alkaline phosphatase in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis

Table 1 Baseline data of patients

Characteristic	Observation group, n = 151	Control group, n = 678	χ 2 / t-value	P-value
Age, yr	50.29 ± 10.07	48.57 ± 10.02	0.516	0.609
Gender
Male	72	310	0.191	0.662
Female	79	368
BMI	20.76 ± 4.51	20.03 ± 4.27	1.701	0.248
Complications
Hypertensive disease	20	68	1.346	0.246
Diabetes mellitus	31	119	0.739	0.390
Hyperlipidemia	16	60	0.452	0.501

BMI: Body mass index.

Table 2 Comparison of serum liver function indexes

Variable	Observation group, n = 151	Control group, n = 678	t-value	P-value
ALT, U/L	35.04 ± 9.18	33.22 ± 9.71	0.354	0.803
AST, U/L	38.96 ± 10.65	36.52 ± 10.33	0.289	0.834
TBIL, μmol/L	11.58 ± 2.87	9.99 ± 1.93	0.417	0.682
DBIL, μmol/L	5.56 ± 0.77	4.95 ± 0.64	0.392	0.786
GGT, U/L	154.56 ± 39.53	35.98 ± 8.19	35.721	0.000
ALP, U/L	171.51 ± 41.74	139.49 ± 36.64	7.317	0.000

ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; TBIL: Total bilirubin; DBIL: Direct bilirubin; GGT: Gamma-glutamyltransferase; ALP: Alkaline phosphatase.

Table 3 Analysis of receiver operating characteristic curve

Variable	Area	Std. Error	Asymptotic Sig	Asymptotic 95%CI	Cutoff value, U/L	Sensitivity	Specificity
GGT	0.881	0.026	0	0.830-0.932	95.5	0.908	0.836
ALP	0.647	0.033	0	0.583-0.711	151.5	0.651	0.598
GGT + ALP	0.923	0.016	0	0.892-0.953	-	0.935	0.851

GGT: Gamma-glutamyltransferase; ALP: Alkaline phosphatase.