Table 3. Comparison of the clinical features of the CA-APN patients with positive and negative blood cultures.
| Clinical characteristics | Positive Blood culture (N = 277) n (%) |
Negative Blood culture (N = 371) n (%) |
P-value |
|---|---|---|---|
| Age≥70 years | 111 (40.1) | 80 (21.6) | <0.001 |
| Past history | |||
| History of urinary tract infection within 1 years | 64/231(27.7) | 100/341(29.3) | 0.674 |
| History of admission within 1 year | 81/256 (31.6) | 72/345 (20.9) | 0.003 |
| History of antibiotics use within 1 year | 69/217 (31.8) | 117/323 (36.2) | 0.289 |
| Co-morbidities | |||
| Charlson comorbidity index ≥1 | 151 (54.5) | 117 (31.5) | <0.001 |
| Diabetes mellitus | 98 (35.4) | 81 (21.8) | <0.001 |
| Chronic renal disease | 25 (9.0) | 12 (3.2) | 0.002 |
| Clinical features | |||
| Pitt score ≥1a | 129 (46.6) | 105 (28.3) | <0.001 |
| Flank pain | 69 (24.9) | 97 (26.1) | 0.721 |
| Symptom of lower urinary tract infection | 164 (59.2) | 249 (67.1) | 0.038 |
| Costovertebral angle tenderness | 164 (59.2) | 242 (65.2) | 0.117 |
| Laboratory findings | |||
| WBC≥20,000/mm3 | 36 (13) | 24 (6.5) | 0.005 |
| CRP≥20 mg/dL | 100(36.1) | 93 (25.1) | 0.002 |
| Clinical outcomes | |||
| Discordant therapyb | 22 (7.9) | 20 (5.4) | 0.192 |
| Duration of hospitalization (days, mean ± SD) | 10.8 ± 7.2 | 8.1 ± 5.4 | <0.001 |
| Defervescence time (days, mean ± SD) | 3.2 ± 2.9 | 2.1 ± 2.5 | 0.014 |
| Hospital mortality | 9/251 (3.6) | 1/338 (0.3) | 0.003 |
| Final clinical failure | 20/251 (8.0) | 9/338 (2.7) | 0.003 |
a See method for calculation of Pitt scores.
bDiscordant therapy was defined as cases whose empirical antimicrobial therapy regimen was changed due to the drug resistance.
CA-APN, community-acquired acute pyelonephritis, WBC, white blood cell; CRP, C-reative protein; SD, standard deviation.