Table 3.
Comparison of Biomarkers Among Individuals With and Without Bacterial Infection Detected
| Biomarkera | Bacterial Infection (n = 22), Median (IQR) | No Bacterial Infection Detected (n = 63), Median (IQR) | Rank Sum P Value |
Area Under the ROC Curve |
|---|---|---|---|---|
| Procalcitonin (ng/mL) | ||||
| Time 0 | 5.95 (0.16–36.31) | 0.65 (0.20–5.04) | .06 | .641 |
| 24 hours | 6.67 (0.76–33.61) | 1.61 (0.31–17.89) | .16 | .614 |
| 48 hours | 3.81 (0.29–39.27) | 1.25 (0.21–12.63) | .40 | .568 |
| 72 hours | 0.97 (0.22–11.39) | 1.61 (0.11–7.17) | .78 | .526 |
| C-reactive protein (mg/dL) | ||||
| Time 0 | 8.7 (3.5–15.3) | 2.2 (0.4–5.8) | <.001 | .766 |
| 24 hours | 9.2 (5.5–16.8) | 3.7 (1.2–7.9) | .002 | .745 |
| 48 hours | 6.1 (2.7–11.8) | 2.8 (0.9–7.8) | .05 | .658 |
| 72 hours | 3.0 (1.8–5.4) | 1.8 (0.5–4.5) | .18 | .620 |
| α2-macroglobulin (mg/dL) | ||||
| Time 0 | 137.3 (109.3–178.1) | 161.5 (123.6–199.7) | .11 | .384 |
| 24 hours | 120.3 (92.5–154.8) | 157.0 (120.7–171.7) | .04 | .337 |
| 48 hours | 116.4 (104.1–127.5) | 150.6 (112.7–185.7) | .004 | .267 |
| 72 hours | 143.1 (80.7–161.4) | 153.1 (122.7–191.6) | .09 | .351 |
| Ferritin (ng/mL) | ||||
| Time 0 | 62.9 (30.0–176.2) | 45.7 (19.0–98.4) | .23 | .587 |
| 24 hours | 79.1 (49.6–228.0) | 53.0 (32.9–117.9) | .09 | .637 |
| 48 hours | 63.8 (42.2–194.6) | 46.6 (27.4–85.0) | .17 | .611 |
| 72 hours | 43.4 (34.2–80.4) | 46.8 (23.3–92.4) | .80 | .523 |
| Haptoglobin (mg/dL) | ||||
| Time 0 | 219.3 (46.0–452.5) | 103.4 (39.2–372.7) | .14 | .606 |
| 24 hours | 369.6 (94.3–498.0) | 106.7 (79.2–402.7) | .09 | .635 |
| 48 hours | 402.6 (144.5–498.0) | 294.0 (38.7–409.6) | .14 | .618 |
| 72 hours | 387.6 (68.3–498.0) | 227.0 (49.7–402.7) | .26 | .602 |
| Serum amyloid A (µg/mL) | ||||
| Time 0 | 18.9 (12.3–26.2) | 11.1 (4.3–22.7) | .009 | .688 |
| 24 hours | 17.8 (12.4–31.5) | 11.4 (7.0–20.5) | .09 | .638 |
| 48 hours | 14.2 (12.7–19.1) | 11.6 (6.1–21.9) | .21 | .602 |
| 72 hours | 11.7 (8.2–18.9) | 7.3 (1.2–11.9) | .03 | .698 |
| Serum amyloid P (ng/mL) | ||||
| Time 0 | 29.2 (22.5–44.3) | 26.7 (19.6–37.3) | .27 | .579 |
| 24 hours | 36.0 (22.5–44.8) | 26.1 (19.1–41.3) | .18 | .608 |
| 48 hours | 36.6 (33.0–43.6) | 30.3 (24.8–36.3) | .05 | .656 |
| 72 hours | 38.6 (28.5–50.3) | 28.4 (21.1–40.7) | .05 | .673 |
| Tissue plasminogen activator (ng/mL) | ||||
| Time 0 | 4.2 (2.9–8.0) | 2.7 (1.6–4.8) | .02 | .671 |
| 24 hours | 3.6 (1.7–7.1) | 2.3 (1.5–3.8) | .07 | .646 |
| 48 hours | 3.2 (2.0–4.1) | 2.4 (1.4–3.3) | .18 | .610 |
| 72 hours | 2.9 (1.5–4.1) | 1.9 (1.1–3.7) | .15 | .630 |
Abbreviations: IQR, interquartile range; ROC, receiver operating characteristic.
aBiomarkers performed at each time point: Time 0 = 85 (80 for procalcitonin), 24 hours = 64 (61 for procalcitonin), 48 hours = 71 (70 for procalcitonin), 72 hours = 58 (57 for procalcitonin). Procalcitonin was performed less often due to limited availability of sample.