Introduction
Materials and methods
Study design and participants
Data collection
Statistical analysis
Results
Clinical parameters of study population
Item | COVID-19 (n = 25) | non-COVID-19 (n = 96) | Mann-Whitney U-test /χ2 | P value |
---|---|---|---|---|
Age Median (IQR) (years) | 71.0 (51.0–79.5) | 66.0 (49.5–73.8) | -1.412 | 0.158 |
Gender, n (%) | 0.273 | 0.601 | ||
Male | 15 (60.0) | 52 (54.2) | ||
Female | 10 (40.0) | 44 (45.8) |
Kolmogorov-sminov test
Laboratory parameters
Item | COVID-19 (n = 25) | non-COVID-19 (n = 96) | Z | P value |
---|---|---|---|---|
CRP (mg/L) | 43.88 (7.76–148.80) | 87.69 (43.21–140.05) | -1.947 | 0.051 |
PCT (ng/mL) | 0.89 (0.10–74.21) | 3.12 (0.27–17.45) | -0. 490 | 0.624 |
TP (g/L) | 60.00 (53.05–64.20) | 61.00 (55.43–67.30) | -1.402 | 0.161 |
ALB (g/L) | 30.80 (28.50–33.95) | 32.05 (28.88–36.95) | -0.615 | 0.539 |
WBC (109/L) | 9.23 (7.24–11.75) | 8.51 (6.11–12.16) | -0.333 | 0.739 |
Neutrophiles (109/L) | 8.11 (4.17–11.11) | 6.48 (3.67–10.88) | -0.653 | 0.514 |
Lymphocytes (109/L) | 0.62 (0.34–1.33) | 0.89 (0.56–1.47) | -1.748 | 0.080 |
PLT (109/L) | 174.00 (103.50–273.00) | 170.50 (98.50–249.00) | -0.285 | 0.776 |
RDW (%) | 13.20 (12.70–15.00) | 14.00 (13.00–15.00) | -0.663 | 0.507 |
NLR | 12.18 (4.98–35.17) | 7.67 (3.48–14.38) | -1.620 | 0.105 |
Biomarkers in GP and GN bacterial infections
Item | GP (n = 49) | GN (n = 72) | Z | P value |
---|---|---|---|---|
CRP (mg/L) | 59.50 (10.41–125.26) | 90.82 (48.25–149.72) | -2.070 | 0.038 |
PCT (ng/mL) | 0.46 (0.15–6.80) | 8.08 (0.95–24.80) | -3.514 | < 0.001 |
TP (g/L) | 60.60 (55.55–65.60) | 60.65 (54.70–62.28) | -0.119 | 0.905 |
ALB (g/L) | 30.70 (28.60–34.30) | 32.25 (29.83–37.23) | -1.362 | 0.173 |
WBC (109/L) | 8.44 (5.46–11.92) | 9.26 (6.54–12.39) | -0.908 | 0.364 |
Neutrophiles (109/L) | 6.12 (3.32–10.20) | 7.89 (4.46–11.27) | -1.064 | 0.287 |
Lymphocytes (109/L) | 0.86 (0.51–1.34) | 0.86 (0.52–1.44) | -0.011 | 0.992 |
PLT (109/L) | 181.00 (110.00–293.50) | 167.00 (88.00–242.00) | -1.489 | 0.136 |
RDW (%) | 14.00 (13.00–16.00) | 14.00 (13.00–15.00) | -0.779 | 0.436 |
NLR | 7.52 (3.33–14.53) | 8.33 (3.69–16.85) | -0.808 | 0.419 |
Prediction of Gram-negative bacterial Infections
Item | PCT | CRP |
---|---|---|
Optimal cutoff | 1.03 ng/mL | 34.02 mg/L |
AUC (95% CI) | 0.689 (0.591–0.786) | 0.611 (0.505–0.717) |
Standard error | 0.050 | 0.054 |
Sensitivity, % (95% CI) | 75.00 (63.91–83.56) | 42.86 (30.02–56.73) |
Specificity, % (95% CI) | 61.22 (47.25–73.57) | 81.94 (71.52–89.13) |
Diagnostic accuracy, % (95% CI) | 69.42(57.16–79.51) | 58.69 (46.83–69.85) |
Positive predictive value, % (95% CI) | 73.97 (64.03–82.29) | 77.71 (60.77–88.46) |
Negative predictive value, % (95% CI) | 62.50 (47.12–75.28) | 49.39 (41.02–58.37) |
Positive likelihood ratio, (95% CI) | 1.93 (1.21–3.16) | 2.37 (1.05–5.22) |
Negative likelihood ratio, (95% CI) | 0.41 (0.22–0.76) | 0.70(0.49–0.98) |
Diagnostic odds ratio, (95% CI) | 4.73 (1.59–14.14) | 3.40 (1.08–10.75) |
Youden’s index (%) | 36.22 | 24.80 |
P value | < 0.001 | 0.039 |
Distribution of microorganisms
Microorganisms | COVID-19 (n = 25) | non-COVID-19 (n = 96) | Chi-square | P value | ||
---|---|---|---|---|---|---|
Gram-positive bacteria (%) | 13 (52.0) | 36 (37.5) | 1.731 | 0.188 | ||
1, Staphylococcus spp. | 9 (36.0) | 17 (17.7) | 3.934 | 0.047 | ||
Staphylococcus aureus | 1 | 6 | ||||
Staphylococcus hominis | 1 | 3 | ||||
Streptococcus mitis | 1 | 4 | ||||
Staphylococcus epidermidis | 6 | 4 | ||||
2, Streptococcus spp. | 2 (8.0) | 15 (15.6) | 0.428 | 0.513 | ||
Streptococcus pneumoniae | 6 | |||||
Streptococcus sanguinis | 1 | |||||
Streptococcus agalactiae | 1 | |||||
Neisseria gonorrhoeae | 1 | |||||
Streptococcus milleri | 1 | |||||
Streptococcus pyogenes | 1 | 2 | ||||
Streptococcus salivarius | 1 | |||||
Streptococcus intermedius | 2 | |||||
Streptococcus adjacens | 1 | 0 | ||||
3, Enterococcus spp. | 2 (8.0) | 4 (4.2) | - | 0.602* | ||
enterococcus faecium | 1 | 0 | ||||
Enterococcus faecalis | 1 | 4 | ||||
Gram-negative bacteria | 12 (48.0) | 60 (62.5) | ||||
4, | Escherichia coli | 10 (40.0) | 36 (37.5) | 0.053 | 0.819 | |
5, | Klebsiella pneumoniae | 2 (8.0) | 18 (18.8) | 0.974 | 0.324 | |
6, | Rare pathogens | 6 |
Bacteria | Number | PCT (IQR) (ng/mL) | Kruskal-Wallis H | P value |
---|---|---|---|---|
Staphylococcus spp. | 26 | 0.28 (0.14–2.61) | 21.959 | < 0.001 |
Streptococcus spp. | 17 | 2.85 (0.22–40.39) | ||
Enterococcus spp. | 6 | 0.29 (0.05–1.49) | ||
Escherichia coli | 46 | 9.43 (1.50–27.72) | ||
Klebsiella pneumoniae | 20 | 6.76 (1.06–23.91) | ||
Rare pathogens | 6 | 0.58 (0.13–35.83) |