Urinary trypsinogens and trypsinogen activation peptide as biomarkers in pediatric acute pancreatitis: A prospective observational study

Table 1 Urinary biomarkers in patients with acute pancreatitis and controls, mean ± SD

Parameter	Patients with AP (n = 61)	Control group (n = 29)	P value
Trypsinogen-1 within 24 hours (ng/mL)	0.91 ± 0.80	0.86 ± 0.43	0.137
Trypsinogen-1 after 48 hours (ng/mL)	0.86 ± 0.59	0.86 ± 0.43	0.384
Trypsinogen-1 after 72 hours (ng/mL)	0.79 ± 0.49	0.86 ± 0.43	0.111
Trypsinogen-2 within 24 hours (ng/mL)	0.50 ± 0.86	0.30 ± 0.12	0.117
Trypsinogen-2 after 48 hours (ng/mL)	0.64 ± 1.19	0.30 ± 0.12	0.022
Trypsinogen-2 after 72 hours (ng/mL)	0.38 ± 0.19	0.30 ± 0.12	0.144
TAP within 24 hours (pg/mL)	52.91 ± 48.60	44.70 ± 22.08	0.963
TAP after 48 hours (pg/mL)	42.21 ± 39.74	44.70 ± 22.08	0.143
TAP after 72 hours (pg/mL)	42.79 ± 28.32	44.70 ± 22.08	0.503

P < 0.05 is statistically significant. AP: Acute pancreatitis; TAP: Trypsinogen activation peptide.

Table 2 Performance of urinary trypsinogen-2 after 48 hours in acute pancreatitis

Parameter	AUC (95%CI)	Cut-off	Se (%)	Sp (%)	PPV (%)	NPV (%)	LR+	LR-	DOR	P value
Trypsinogen-2 after 48 hours (ng/mL)	0.651 (0.535-0.767)	0.381	48.3	82.8	84.8	44.4	2.8	0.625	4.48	0.010

P < 0.05 is statistically significant. AUC: Area under the curve; DOR: Diagnostic odds ratio; LR: Likelihood ratio; NPV: Negative predictive value; PPV: Positive predictive value; Se: Sensitivity; Sp: Specificity.

Table 3 Urinary biomarkers at three time points in acute pancreatitis, mean ± SD

Parameter	Within 24 hours	After 48 hours	After 72 hours	P value
Trypsinogen-1 (ng/mL)	0.91 ± 0.80	0.86 ± 0.59	0.79 ± 0.49	0.164
Trypsinogen-2 (ng/mL)	0.50 ± 0.86	0.64 ± 1.19	0.38 ± 0.19	0.670
TAP (pg/mL)	52.91 ± 48.60	42.21 ± 39.74	42.79 ± 28.32	0.504

P < 0.05 is statistically significant. TAP: Trypsinogen activation peptide.

Table 4 Biomarkers in mild and moderately severe acute pancreatitis, mean ± SD

Parameter	Mild AP (n = 49)	Moderately severe AP (n = 12)	P value
Trypsinogen-1 within 24 hours (ng/mL)	0.86 ± 0.75	1.09 ± 1.00	0.973
Trypsinogen-1 after 48 hours (ng/mL)	0.85 ± 0.51	0.89 ± 0.85	0.484
Trypsinogen-1 after 72 hours (ng/mL)	0.82 ± 0.52	0.66 ± 0.35	0.411
Trypsinogen-2 within 24 hours (ng/mL)	0.52 ± 0.95	0.43 ± 0.15	0.256
Trypsinogen-2 after 48 hours (ng/mL)	0.70 ± 1.33	0.44 ± 0.28	0.803
Trypsinogen-2 after 72 hours (ng/mL)	0.37 ± 0.18	0.41 ± 0.24	0.632
TAP within 24 hours (pg/mL)	55.27 ± 52.30	42.25 ± 25.42	0.608
TAP after 48 hours (pg/mL)	37.84 ± 35.60	58.94 ± 51.11	0.043
TAP after 72 hours (pg/mL)	37.11 ± 26.81	64.58 ± 23.76	0.001
CRP at admission (mg/L)	12.41 ± 25.37	25.45 ± 50.61	0.468
CRP after 48 hours (mg/L)	16.54 ± 25.06	65.84 ± 54.73	0.002
CRP after 72 hours (mg/L)	18.53 ± 23.99	105.90 ± 83.61	< 0.001

P < 0.05 is statistically significant. AP: Acute pancreatitis; CRP: C-reactive protein; TAP: Trypsinogen activation peptide.

Table 5 Performance of biomarkers in predicting acute pancreatitis severity

Parameter	AUC (95%CI)	Cut-off	Se (%)	Sp (%)	PPV (%)	NPV (%)	LR+	LR-	DOR	P value
TAP after 48 hours (pg/mL)	0.692 (0.542-0.842)	25.412	83.3	54.3	32.3	92.6	1.825	0.307	5.945	0.012
TAP after 72 hours (pg/mL)	0.810 (0.692-0.928)	43.844	83.3	73.9	45.5	94.4	3.194	0.225	14.196	< 0.001
CRP after 48 hours (mg/L)	0.794 (0.642-0.946)	21.900	75.0	79.6	47.4	92.9	3.675	0.314	11.704	< 0.001
CRP after 72 hours (mg/L)	0.857 (0.717-0.998)	60.890	75.0	89.8	64.3	93.6	7.350	0.278	26.439	< 0.001

P < 0.05 is statistically significant. AUC: Area under the curve; CRP: C-reactive protein; DOR: Diagnostic odds ratio; LR: Likelihood ratio; NPV: Negative predictive value; PPV: Positive predictive value; Se: Sensitivity; Sp: Specificity; TAP: Trypsinogen activation peptide.

Table 6 Univariate logistic regression for predictors of acute pancreatitis severity

Parameter	OR	95%CI (OR)	P value
TAP after 48 hours	1.012	0.997-1.027	0.118
TAP after 72 hours	1.034	1.009-1.059	0.007
CRP after 48 hours	1.031	1.012-1.050	0.001
CRP after 72 hours	1.039	1.017-1.061	0.001

P < 0.05 is statistically significant. CRP: C-reactive protein; OR: Odds ratio; TAP: Trypsinogen activation peptide.