Table 2. VIP and AUC values of synovial fluid metabolites to be used as potential biomarkers for discriminating Behçet's disease with arthritis from seronegative arthritis.
| Metabolite | BD vs. SNA | BD vs. SNRA | BD vs. SNSpA | ||||||
|---|---|---|---|---|---|---|---|---|---|
| VIP | AUC | P-value | VIP (rank) | AUC | P-value | VIP (rank) | AUC | P-value | |
| Glutamate | 2.68 | 0.870 | 0.001 | 2.01 (4) | 1.000 | 0.001 | 2.38 (1) | 0.821 | 0.010 |
| Citramalate | 2.55 | 0.861 | 0.002 | 1.93 (5) | 1.000 | 0.002 | 2.24 (2) | 0.808 | 0.017 |
| Valine | 2.34 | 0.833 | 0.006 | 1.79 (9) | 1.000 | 0.006 | 2.02 (3) | 0.769 | 0.034 |
| Leucine | 2.18 | 0.815 | 0.012 | 1.90 (5) | 0.769 | 0.048 | |||
| Methionine sulfoxide | 2.17 | 0.815 | 0.012 | 2.24 (1) | 1.000 | < 0.001 | |||
| Glycerate | 2.16 | 0.796 | 0.013 | 1.80 (8) | 0.967 | 0.006 | |||
| Phosphate | 2.08 | 0.815 | 0.017 | ||||||
| Lysine | 2.01 | 0.806 | 0.022 | 1.94 (4) | 0.782 | 0.043 | |||
| Isoleucine | 1.93 | 0.787 | 0.028 | ||||||
| Urea | 1.85 | 0.852 | 0.036 | ||||||
| Citrulline | 1.77 | 0.787 | 0.046 | ||||||
| Glutamine | 2.19 (2) | 1.000 | < 0.001 | ||||||
| Oxoproline | 2.11 (3) | 1.000 | < 0.001 | ||||||
| Threonine | 1.88 (6) | 1.000 | 0.003 | ||||||
| Methionine | 1.84 (7) | 0.900 | 0.004 | ||||||
| 3,6-anhdyro-D-galatose | 1.79 (10) | 0.967 | 0.006 | ||||||
| Capric acid | 1.75 (11) | 0.967 | 0.008 | ||||||
AUC, Area under the receiver operator characteristics curve; BD, Behcet’s disease with arthritis; SNA, Seronegative arthritis; SNRA, Seronegative rheumatoid arthritis; SNSpA, seronegative spondyloarthropathy; VIP, variable importance in projection. P-values were determined using the Wilcoxon-Mann-Whitney test.