Table 4.
Bacterial culture and paired analysis
| Variable | MSU n = 31 |
CSU n = 31 |
Z | P | ||
|---|---|---|---|---|---|---|
| Number of species identified | ||||||
| No growth | 0 | – | 16 | (47.1) | ||
| 1 | 2 | (5.9) | 12 | (35.3) | ||
| 2 | 6 | (17.6) | 3 | (8.8) | −4.78 | <0.001* |
| 3 | 11 | (32.4) | 1 | (2.9) | ||
| 4 | 11 | (32.4) | 0 | – | ||
| 5 | 2 | (5.9) | 0 | – | ||
| Routine laboratory culturea | ||||||
| Screening culture negative | 13 | (40.6) | 28 | (87.5) | −3.66 | <0.001* |
| No significant growth | 6 | (18.8) | 1 | (3.1) | ||
| Mixed growth, uncertain significance | 3 | (9.4) | 0 | – | ||
| Growth × 104–105 | 1 | (3.1) | 0 | – | ||
| Growth × 105 | 8 | (25.0) | 0 | – | ||
| Growth, no bacterial count | 0 | – | 2 | (6.3) | ||
| Missing | 1 | (3.1) | 1 | (3.1) | ||
Data reported as n (%) or median (IQR) and paired analysis performed by Wilcoxon signed ranks test. MSU samples grew more bacteria on sediment culture and routine laboratory culture
aTreatment threshold by routine laboratory culture set at total cfu/ml ≥ 105