Table 3.
Procalcitonin cutoffs (0.1 and 0.25 μg/L) for risk prediction in different clinical settings and in various acute respiratory infection subgroups a
| Cutoff (μg/L) | 0.1 μg/L | 0.25 μg/L | ||||||
|---|---|---|---|---|---|---|---|---|
| Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | |
| (95% CI) | (95% CI) | (95% CI) | (95% CI) | (95% CI) | (95% CI) | (95% CI) | (95% CI) | |
| PC | ||||||||
| Treatment failure | 19.8 (15.6, 24.6) | 81.3 (78.2, 84.1) | 33.3 (26.7, 40.5) | 68.2 (64.9, 71.4) | 3.41 (1.71, 6.01) | 98.1 (96.8, 99.0) | 45.8 (25.6, 67.2) | 68.3 (65.2, 71.2) |
| ED | ||||||||
| Treatment failure | 86.1 (82.4, 89.3) | 26.1 (24.2, 28.0) | 17.9 (16.2, 19.7) | 90.9 (88.4, 93.1) | 65.6 (60.8, 70.2) | 53.1 (51.0, 55.2) | 20.8 (18.6, 23.1) | 89.2 (87.4, 90.8) |
| Mortality | 92.5 (86.2, 96.5) | 25.0 (23.3, 26.7) | 5.63 (4.65, 6.74) | 98.6 (97.3, 99.3) | 72.5 (63.6, 80.3) | 51.2 (49.3, 53.2) | 6.71 (5.4, 8.2) | 97.5 (96.5, 98.3) |
| ICU | ||||||||
| Mortality | 95.2 (89.8, 98.2) | 4.21 (2.43, 6.75) | 24.6 (20.9, 28.7) | 72.7 (49.8, 89.3) | 80.8 (72.8, 87.3) | 18.9 (15.1, 23.3) | 24.7 (20.6, 29.2) | 75.0 (65.1, 83.3) |
| Total lower ARI | ||||||||
| Treatment failure | 76.4 (72.9, 79.6) | 28.2 (26.5, 29.9) | 19.6 (18.1, 21.2) | 83.9 (81.4, 86.1) | 57.4 (53.5, 61.3) | 52.8 (51.0, 54.7) | 21.8 (19.9, 23.9) | 84.4 (82.6, 86.0) |
| Mortality | 94.5 (90.8, 97.0) | 28.9 (27.4, 30.5) | 8.89 (7.8, 10.1) | 98.6 (97.7, 99.3) | 78.1 (72.2, 83.2) | 53.0 (51.3, 54.8) | 10.9 (9.42, 12.4) | 97.1 (96.2, 97.8) |
| Bronchitis | ||||||||
| Treatment failure | 28.6 (20.2, 38.2) | 68.0 (63.3, 72.4) | 18.1 (12.5, 24.8) | 79.4 (74.9, 83.4) | 3.81 (1.05, 9.47) | 92.5 (89.5, 94.8) | 11.1 (3.11, 26.1) | 79.6 (75.7, 83.0) |
| Mortality | 100 (15.8, 100) | 68.9 (64.8, 72.9) | 1.20 (0.15, 4.28) | 100 (99.0, 100) | 0.00 (0.00, 84.2) | 93.2 (90.7, 95.2) | 0.00 (0.00, 9.74) | 99.6 (98.5, 100) |
| ECOPD | ||||||||
| Treatment failure | 60.0 (48.4, 70.8) | 49.8 (45.3, 54.3) | 16.0 (12.0, 20.6) | 88.7 (84.4, 92.1) | 27.5 (18.1, 38.6) | 85.9 (82.5, 88.8) | 23.7 (15.5, 33.6) | 88.1 (84.9, 90.9) |
| Mortality | 82.4 (56.6, 96.2) | 49.4 (45.2, 53.6) | 4.67 (2.57, 7.71) | 98.9 (96.9, 99.8) | 47.1 (23.0, 72.2) | 85.0 (81.7, 87.8) | 8.60 (3.79, 16.2) | 98.2 (96.5, 99.2) |
| CAP | ||||||||
| Treatment failure | 92.5 (89.5, 94.8) | 12.1 (10.5, 13.8) | 22.2 (20.3, 24.2) | 85.5 (80.2, 89.9) | 77.1 (72.8, 81.0) | 35.0 (32.6, 37.4) | 24.3 (22.1, 26.7) | 84.9 (81.9, 87.6) |
| Mortality | 94.9 (90.9, 97.5) | 11.8 (10.3, 13.4) | 10.6 (9.20, 12.1) | 95.5 (91.8, 97.8) | 81.2 (75.1, 86.4) | 33.9 (31.7, 36.1) | 11.9 (10.2, 13.8) | 94.2 (92.2, 95.9) |
aARI, Acute respiratory tract infection; CAP, Community-acquired pneumonia; CI, Confidence interval; ECOPD, Exacerbated chronic obstructive pulmonary disease; ED, Emergency department; ICU, Intensive care unit; NA, Not applicable due to small sample size; NPV, Negative predictive value; PC, Primary care; PCT, Procalcitonin; PPV, Positive predictive value.