Table 2.
Fifteen metabolites discriminating CAP from controls in the discovery cohort
| Metabolite/pathway | ESI mode | Mass (m/z) | RT (min) | VIP | FDR | FCa | CV%b |
|---|---|---|---|---|---|---|---|
| Sphingolipid metabolism | |||||||
| Phytosphingosine | Pos | 318.3003 | 3.7428 | 5.1690 | 2.99×10–18 | 0.2005 | 8.45 |
| Sphinganine | Pos | 302.3054 | 3.7117 | 3.5729 | 3.74×10–12 | 0.2276 | 10.90 |
| Palmitoyl sphingomyelin (SM(d18:1/16:0)) | Pos | 703.5754 | 5.9542 | 4.2044 | 1.31×10–5 | 1.6366 | 29.79 |
| Arginine and proline metabolism | |||||||
| Creatine | Pos | 132.0773 | 9.4855 | 2.6225 | 8.71×10–4 | 1.6254 | 9.13 |
| l-Arginine | Pos | 175.1195 | 11.6748 | 3.6558 | 1.18×10–6 | 1.3980 | 5.83 |
| Pyruvate metabolism | |||||||
| Lactate | Neg | 89.0239 | 6.9559 | 3.4407 | 1.04×10–3 | 1.3259 | 5.50 |
| Inositol phosphate metabolism | |||||||
| Myoinositol | Neg | 179.0561 | 8.2464 | 3.8451 | 6.54×10–5 | 1.4138 | 6.81 |
| 2-Hydroxy-3-methylbutyric acid | Neg | 117.0557 | 4.7190 | 3. 6752 | 1.63×10–6 | 2.0376 | 18.88 |
| Other metabolisms | |||||||
| 4-Hydroxybenzenesulfonic acid | Neg | 172.9914 | 0.7999 | 4.6749 | 1.19×10–4 | 0.3932 | 3.19 |
| Methoxyacetic acid | Neg | 89.0239 | 6.9220 | 3.4407 | 1.04×10–3 | 1.3259 | 5.50 |
| Ketoleucine | Neg | 129.0552 | 2.4610 | 6.8758 | 2.65×10–3 | 0.8778 | 7.01 |
| l-Acetylcarnitine | Pos | 204.1230 | 8.3173 | 3.9173 | 2.91×10–5 | 2.1304 | 27.89 |
| Glycerophosphocholine | Pos | 258.1101 | 10.8398 | 11.0112 | 6.98×10–7 | 0.2979 | 24.21 |
| DHEA-S | Neg | 367.1579 | 0.9317 | 3.6010 | 7.68×10–5 | 0.5623 | 4.65 |
| p-Cresol sulfate | Neg | 187.0065 | 0.7839 | 9.9153 | 1.18×10–2 | 0.5306 | 3.54 |
CAP community-acquired pneumonia, ESI election spray ionization, RT retention time, VIP variable importance in the projection, FDR false discovery rate, FC fold change, CV coefficient of variation, Pos positive, Neg negative, DHEA-S dehydroepiandrosterone sulfate
aRatio of relative high intensity present in CAP patients to controls
bCV% for quality control sample