Bedside score predicting retained common bile duct stone in acute biliary pancreatitis

Table 1 Demographics and laboratory characteristics of study cohort

Parameters	Group A (without stones)	Group B (with stones)
Number of patients	121	33
Age (yr) (mean ± SD)	54.8 ± 18.8	68.9 ± 14.3
Gender, n (%)
Male	57 (47)	11 (33.3)
Female	64 (53)	22 (66.7)
Alanine aminotransferase, U/L	171.9 ± 238.9	363.3 ± 347
Aspartate transaminase, U/L	170.7 ± 267.4	387.7 ± 290.5
Alkaline phosphatase, U/L	143.6 ± 122.1	246.7 ± 133.1
Gamma-glutamyltransferase, U/L	291.1 ± 284	594.4 ± 385.2
Total bilirubin, mg/dL	2.2 ± 5.2	3.4 ± 2.6
White blood cells (× 103/cm)	11.6 ± 4.5	12.7 ± 4.7
Common bile duct width by US (mm)	6.4 ± 1.6	7.3 ± 2.9

US: Ultrasound.

Table 2 Univariate analysis of parameters associated with common bile duct stones

Parameter	Odds ratio	Lower 95% confidence limit for odds ratio	Upper 95% confidence limit for odds ratio	P value
Age	1.048	1.021	1.076	0.0004
Gender, male vs female	0.573	0.258	1.276	0.1728
Aspartate transaminase	1.002	1.001	1.004	0.0015
Alkaline phosphatase	1.005	1.002	1.008	0.0005
Gamma-glutamyltransferase	1.003	1.001	1.004	0.0002
Total bilirubin	1.033	0.964	1.108	0.3515
White blood cells	1.052	0.970	1.142	0.2190
Common bile duct width by US (mm)	1.187	1.004	1.402	0.0445
Common bile duct dilation by US	4.032	1.601	10.153	0.0031

US: Ultrasound.

Table 3 Variables that were independently associated with common bile duct stones and their corresponding weight points given according to coefficient estimates

Parameters	Coefficient estimate	Odds ratio (95%CI)	P value	Weights appointed for the score
Age	0.05 ± 0.01	1.061 (1.026-1.097)	0.0005	× 0.5
Dilated common bile duct by US	1.3 ± 0.058	3.685 (1.160-11.711)	0.0270	× 10
Gamma-glutamyltransferase (U/L)	0.002 ± 0.0007	1.003 (1.001-1.004)	0.0003	× 0.02

US: Ultrasound.

Table 4 Equation generated cut-off points with their corresponding diagnostic statistics [age (yr) × 0.5 + gamma-glutamyl transferase (U/L) × 0.02 + common bile duct width by ultrasound (mm) × 10]

Score	Sensitivity	Specificity	PPV	NPV
51-74	20-46	90-100	65-100	77-83
41-51	52-79	70-88	50-61	83-90
9-41	82-100	58-69	47-50	91-100