TABLE 1.
Comparative analysis of cases with MDR and non-MDR bloodstream infections caused by P. aeruginosa
| Variablee | Totala,d | MDRb | Non-MDRc | P |
|---|---|---|---|---|
| Median age (IQR) | 66.0 (55.0–77.0) | 63.0 (55.0–73.0) | 67.0 (55.0–78.0) | 0.079 |
| No. (%) of males | 161 (66.3) | 56 (60.2) | 105 (70.0) | 0.153 |
| Comorbidity | ||||
| Charlson comorbidity index | 2 (2–3) | 2 (2–4) | 2 (1–3) | 0.513 |
| No. diabetes mellitus (%) | 63 (25.9) | 31 (33.3) | 32 (21.3) | 0.054 |
| No. end-stage renal disease (%) | 41 (16.9) | 12 (12.9) | 29 (19.3) | 0.261 |
| No. solid malignancy (%) | 50 (20.6) | 19 (20.4) | 31 (20.7) | 0.965 |
| No. hematological malignancy (%) | 62 (25.5) | 31 (33.3) | 31 (20.7) | 0.040 |
| No. severe neutropenia (%) | 58 (23.9) | 30 (32.3) | 28 (18.7) | 0.024 |
| No. transplant (%) | 52 (21.4) | 19 (20.4) | 33 (22.0) | 0.897 |
| No. prior MDR colonization (%) | 34 (13.9) | 31 (33.3) | 3 (2.0) | <0.001 |
| No. ICU admission in previous 3 mo. (%) | 44 (18.1) | 17 (18.3) | 27 (18.0) | 0.956 |
| Prior invasive procedures | ||||
| No. venous catheter (%) | 146 (60.1) | 70 (75.3) | 76 (50.7) | <0.001 |
| No. urinary catheter (%) | 107 (44.0) | 41 (44.1) | 66 (44.0) | 0.989 |
| No. mechanical ventilation (%) | 36 (14.8) | 17 (18.3) | 19 (12.7) | 0.312 |
| No. surgery in previous mo. (%) | 81 (33.3) | 37 (39.8) | 44 (29.3) | 0.124 |
| No. antimicrobial therapy in previous mo. (%) | 170 (69.9) | 82 (88.2) | 88 (58.7) | <0.001 |
| No. carbapenems (%) | 54 (22.2) | 36 (38.7) | 18 (12.0) | <0.001 |
| No. fluoroquinolones (%) | 52 (21.4) | 29 (31.2) | 23 (15.3) | 0.006 |
| Acquisition type | ||||
| No. nosocomial (%) | 137 (56.4) | 71 (76.3) | 66 (44.0) | <0.001 |
| No. healthcare-associated (%) | 82 (33.7) | 22 (23.7) | 60 (40.0) | 0.013 |
| No. community (%) | 24 (9.9) | 0 (0) | 24 (16.0) | <0.001 |
| Ward of admission | ||||
| No. medical (%) | 120 (49.4) | 29 (31.2) | 91 (60.7) | <0.001 |
| No. onco-hematological (%) | 51 (21.0) | 28 (30.1) | 23 (15.3) | 0.009 |
| No. surgical (%) | 29 (11.9) | 14 (15.1) | 15 (10.0) | 0.328 |
| No. critical care (%) | 43 (17.7) | 22 (23.7) | 21 (14.0) | 0.081 |
| Primary source of infection | ||||
| No. high-risk source (%) | 150 (61.7) | 67 (72.0) | 83 (55.3) | 0.014 |
| No. unknown (%) | 26 (10.7) | 8 (8.6) | 18 (12.0) | 0.536 |
| No. respiratory (%) | 55 (22.6) | 33 (35.5) | 22 (14.7) | <0.001 |
| No. abdominal (%) | 50 (20.6) | 21 (22.6) | 29 (19.3) | 0.656 |
| No. soft tissue (%) | 19 (7.8) | 5 (5.4) | 14 (9.3) | 0.330 |
| Low-risk source | 93 (38.3) | 26 (27.9) | 67 (44.7) | 0.014 |
| No. urinary (%) | 67 (27.6) | 18 (19.4) | 49 (32.7) | 0.035 |
| No. vascular catheter (%) | 23 (9.5) | 7 (7.5) | 16 (10.7) | 0.557 |
| No. other (%) | 3 (1.2) | 1 (1.1) | 2 (1.3) | 1.000 |
| Clinical presentation | ||||
| No. Pitt bacteremia score ≥2 (%) | 135 (55.6) | 60 (64.5) | 75 (50.0) | 0.038 |
| No. septic shock (%) | 66 (27.2) | 32 (34.4) | 34 (22.7) | 0.064 |
| No. inadequate empiric antibiotic (%) | 85 (34.9) | 55 (59.1) | 30 (20.0) | <0.001 |
| Carbapenemase type/ST | ||||
| No. VIM-2/ST175 (%) | 43 (17.7) | 43 (46.2) | 0 (0) | <0.001 |
| No. GES-5/ST235 (%) | 33 (13.6) | 33 (35.5) | 0 (0) | <0.001 |
| TTSS genotype | ||||
| No. exoU+/exoS− (%) | 50 (20.6) | 33 (35.5) | 17 (11.3) | <0.001 |
| No. exoU−/exoS+ (%) | 185 (76.1) | 59 (63.4) | 126 (84.0) | <0.001 |
| No. exoU−/exoS− (%) | 8 (3.3) | 1 (1.1) | 7 (4.7) | 0.001 |
| O-antigen serotype | ||||
| No. O1 (%) | 38 (15.6) | 8 (8.6) | 30 (20.0) | 0.028 |
| No. O4 (%) | 50 (20.6) | 44 (47.3) | 6 (4.0) | <0.001 |
| No. O6 (%) | 38 (15.6) | 6 (6.5) | 32 (21.3) | <0.001 |
| No. O11 (%) | 37 (15.2) | 29 (31.2) | 8 (5.3) | <0.001 |
| No. other O-types (%) | 80 (32.9) | 6 (6.5) | 74 (49.3) | <0.001 |
| Median TTP (hours) of blood culture (IQR)f | 16.0 (12.0–19.0) | 16.0 (12.0–19.0) | 15.0 (12.0–18.0) | 0.553 |
| Outcome | ||||
| No. 5-day mortality (early mortality) (%) | 49 (20.2) | 32 (34.4) | 17 (11.3) | <0.001 |
| No. 30-day mortality (late mortality) (%) | 81 (33.3) | 49 (52.7) | 32 (21.3) | <0.001 |
a
Total cases; n = 243, 100%.
b
Cases with MDR infections; n = 93, 38.3%.
c
Cases with non-MDR infections; n = 150, 61.7%.
d
Data are expressed as n (%) or median (IQR).
e
MDR, multidrug-resistant; ICU, intensive care unit; ST, sequence type; TTSS, type III secretion system; TTP, time to positivity.
f
Time from the start of incubation to the alert signal in the blood culture system.