Table 3.

Statistical analysis of 50 differential metabolites in urine identified from the comparison of HSPN (+) vs. HSPN (–).

Differential metabolites	Retention time (min)	Mass-to-charge ratio	VIP	Fold change	P-valuea	Adduct
10,20-Dihydroxyeicosanoic acid	10.71	362.3240	3.41	1.37	<0.001	M+NH4
7-Hydroxyoctadecanoic acid	10.63	318.3003	3.16	1.27	<0.001	M+NH4
Choline*	0.65	104.1070	3.15	1.44	<0.001	M+H
5-Ethenylbenzene-1,2,3-triolb	4.52	151.0406	2.84	0.58	0.002	M–H
Valyl-Leucine	4.48	231.1698	2.83	6.08	0.005	M+H
Dodecanedioic acid	7.23	231.1581	2.83	0.48	0.006	M+H
1,2,3,4-Tetrahydroisoquinoline	7.27	134.0961	2.71	0.67	0.008	M+H
Dihydroxy-1H-indole glucuronide Ib	2.94	324.0731	2.67	1.45	0.036	M–H
N-Acetyl-a-neuraminic acid	0.75	310.1136	2.55	1.29	0.014	M+H
Perillic acid	5.99	167.1063	2.41	0.57	0.007	M+H
Genistein 4′,7-O-diglucuronide	5.18	623.1245	2.37	0.31	<0.001	M+H
3-Phenylpropionylglycineb	4.31	206.0827	2.36	1.69	0.004	M–H
3-Hydroxytetradecanedioic acidb	6.91	273.1709	2.19	0.51	0.001	M–H
Cyclohexane	6.00	107.0838	2.15	0.71	0.039	M+Na
2,6-Dimethylheptanoyl carnitine	8.71	302.2325	2.10	0.62	0.008	M+H
Urocanic acidb	2.41	137.0355	2.06	1.28	0.003	M–H
(3-Phenyloxiran-2-yl) methanolb	7.46	149.0609	2.06	0.55	0.032	M–H
[N-acetylneuraminosyl (a2–6) lactosamine]	0.83	675.2462	2.05	1.19	0.027	M+H
5-Ethyl-3-methoxybenzene-1,2,4-triol	3.65	202.1068	2.03	0.78	0.037	M+NH4
Alpha-CEHC glucuronideb	7.58	453.1770	1.98	0.32	0.042	M–H
N-Acetylaminooctanoic acidb	6.41	200.1296	1.97	1.29	0.002	M–H
5′-Carboxy-gamma-chromanol	9.12	324.2163	1.91	0.64	0.023	M+NH4
Creatine riboside	0.75	264.1179	1.91	1.74	0.003	M+H
Pyruvic acidb*	0.56	87.00843	1.90	0.77	0.003	M–H
Vanillic acid 4-O-sulfateb	2.94	246.9922	1.85	0.61	0.010	M–H
Adenosine 2′,3′-cyclic phosphate	2.79	330.0597	1.84	0.74	0.017	M+H
Androsterone glucuronide	10.02	484.2900	1.82	0.64	0.049	M+NH4
L-Hexanoylcarnitine	5.93	260.1856	1.67	0.59	0.014	M+H
Adenosine*	2.60	268.1037	1.64	0.74	0.006	M+H
Tyrosyl-Proline	3.86	279.1333	1.62	0.66	0.018	M+H
6-Hydroxy-5-methoxyindole Glucuronide	4.65	340.1028	1.60	0.72	0.013	M+H
8-Hydroxy-7-methylguanine	2.89	182.0670	1.60	1.24	0.020	M+H
Threoninyl-Tyrosine	6.32	283.1282	1.59	0.76	0.021	M+H
3-Hydroxy-4-aminopyridine	0.74	111.0552	1.58	0.84	0.004	M+H
3-Furoic acidb	0.55	111.0082	1.58	0.83	0.032	M–H
Alpha-Carboxy-delta-decalactoneb	3.90	213.1135	1.55	0.67	0.017	M–H
4-Methoxybenzene-1,3-diolb	4.33	139.0403	1.53	0.71	0.004	M–H
4-Hydroxybenzaldehydeb	4.17	121.0294	1.50	1.74	0.007	M–H
Cis-vaccenic acid*	11.56	300.2875	1.48	1.10	0.028	M+NH4
(4-Ethyl-2,6-dihydroxyphenyl) Oxidanesulfonic acidb	5.20	233.0127	1.48	0.64	0.017	M–H
Phenylbutyrylglutamine	8.21	315.1326	1.41	0.78	0.040	M+Na
Pyrogallol-2-O-sulfateb	2.77	204.9817	1.39	0.67	0.002	M–H
But-2-enoic acidb	0.57	85.02898	1.39	0.87	0.024	M–H
Arginyl-Gamma-glutamate	3.85	320.2052	1.38	0.75	0.019	M+NH4
4-Ethylbenzaldehydeb	7.89	133.0658	1.37	0.69	0.011	M–H
Heptanoylcarnitine	7.10	274.2012	1.36	0.42	0.009	M+H
Pregnanediol-3-glucuronideb	9.36	495.2969	1.31	0.64	0.005	M–H
p-Cresolb	5.20	153.0557	1.21	0.72	0.011	M+FA–H
5-Decenoic acid	8.73	171.1369	1.21	0.75	0.045	M+H
11,12,15-Trihydroxyeicosatrienoic acid	8.75	372.2741	1.13	0.61	0.022	M+NH4

^*means that the metabolites were confirmed with reference compounds.

The metabolites were listed in a decreasing order based on VIP values.

Fold change with a value >1 indicates a relatively higher concentration present in the HSPN (+) patients.

^ap-values from Mann–Whitney U-test;

^bmeans that the metabolite was detected in negative ion mode.