Table 1.
Differential characteristics between colonized and infected individuals, by A. baumannii (n=122)
| Parameter | Colonized patients (n=73) | Infected patients (n=49) | p univariant | Multivariant analysis
|
|
|---|---|---|---|---|---|
| Exp(B) (95% CI) | p | ||||
| Age (years), mean ± standard deviation | 65±15 | 55±18 | 0.002 | ||
| Sex (male), n (%) | 44 (60) | 39 (80) | 0.030 | ||
| Present admission at ICU, n (%) | 27 (37) | 32 (65) | 0.002 | 4.55 (1.79–11.53) | 0.001 |
| Previous admission at ICU, n (%) | 42 (57) | 43 (88) | <0.001 | ||
| Length of stay previous to isolation of A. baumannii (days) | 22±19 | 31±36 | 0.049 | 1.02 (1.01–1.04) | 0.012 |
| Presence of intrinsic risk factors (chronic underlying condition), n (%)a | 65 (89) | 30 (61) | 0.001 | ||
| McCabe classification, n (%) | 0.001 | ||||
| Non-fatal | 31 (43) | 37 (76) | 2.94 (1.26–2.89) | 0.013 | |
| Ultimately or rapidly fatal | 42 (58) | 12 (24) | |||
| Charlson index, mean ± standard deviation | 2.95±2.34 | 1.31±2.05 | <0.001 | ||
| APACHE II scoreb, mean ± standard deviation | 22±8 | 23±9 | 0.309 | ||
| Presence of extrinsic risk factors, n (%) | |||||
| Central venous catheter | 50 (69) | 40 (82) | 0.142 | ||
| Urinary catheter | 55 (75) | 43 (88) | 0.108 | ||
| Parenteral nutrition | 7 (10) | 2 (4) | 0.312 | ||
| Enteral nutrition | 27 (37.0) | 34 (69.4) | 0.001 | ||
| Mechanical ventilation | 25 (34.2) | 26 (53.1) | 0.042 | ||
| Tracheostomy | 6 (8.2) | 13 (26.5) | 0.010 | ||
| Major surgical procedure | 26 (35.6) | 13 (26.5) | 0.327 | ||
| Cerebrospinal fluid derivation | 5 (7) | 11 (22) | 0.402 | ||
| Digestive endoscopy in previous week | 0 | 2 (4) | 0.159 | ||
| Antibiotic therapy in the previous 90 days | 70 (96) | 46 (94) | 0.683 | ||
| Treatment with carbapenems in the previous 90 days | 29 (40) | 20 (41) | 1.000 | ||
| Isolation sites for A. baumannii, n (%) | <0.001 | ||||
| Sputum | 6 (8) | 7 (14) | |||
| Tracheal aspirate | 26 (36) | 36 (74) | |||
| Blood | 0 (0) | 3 (6) | |||
| Urine | 10 (14) | 0 (0) | |||
| Ascitic fluid | 2 (3) | 1 (2) | |||
| Surgical wound | 18 (25) | 1 (2) | |||
| Others | 11 (15) | 1 (2) | |||
| Resistance pattern, n (%) | 0.081 | ||||
| Susceptible | 3 (4) | 0 | |||
| Multidrug resistant | 18 (25) | 6 (12) | |||
| Extensively resistant | 52 (71) | 42 (86) | |||
| Pandrug resistant | 0 (0) | 1 (2) | |||
Notes:
a
The presence of cardiac (colonized, 30 [41%] patients; infected, seven [14%] cases; p=0.002) and respiratory (colonized, 21 [29%] patients; infected, four [8%] cases; p=0.006) chronic underlying conditions was significantly more frequent in colonized individuals. The rest of the intrinsic risk factors did not show significant differences between both groups.
b
APACHE II was measured only in patients in ICU (n=59; colonized, 27 cases; infected, 32 cases).
Abbreviations: A. baumannii, Acinetobacter baumannii; CI, confidence interval; ICU, intensive care unit; APACHE, Acute Physiology and Chronic Health Evaluation.