Table 2.
Clinical data of investigated adult bloodstream infection (BSI) cases due to Enterobacter cloacae (Ecl) isolates: difference between cases due to inducible (Ind-Ecl) and derepressed (Der-Ecl) isolates and factors associated with mortality.a,b
| Data | All BSI-Ecl cases | Ind-Ecl | Der-Ecl | P-value | No. deaths/no. cases |
P-value |
|---|---|---|---|---|---|---|
| Adult BSI cases analysedc | 43 | 26 | 17 | NA | 6 | NA |
| Female sex | 18 (41.9) | 6 (23.1) | 12 (70.6) | 0.004 | 4/18 (22.2) | NS |
| Age (years) (mean ± S.D.) | 59.5 ± 13.6 | 58.3 ± 11.9 | 61.4 ± 16.2 | NS | 65.3 | NS |
| McCabe–Jackson classification | ||||||
| Non-fatal | 20(46.5) | 10(38.5) | 10(58.8) | NSd | 2/20 (10.0) | NSd |
| Ultimately fatal | 22(51.2) | 15 (57.7) | 7 (41.2) | 3/22 (13.6) | ||
| Rapidly fatal | 1 (2.3) | 1 (3.8) | – | 1/1 (100) | ||
| Charlson weighted index (mean ± S.D.) | 4.3 ± 3.6 | 4.0 ± 3.8 | 4.6 ± 3.3 | NS | 9.5 ± 2.1 | 0.046 |
| Previous hospitalisation (during the last 12 months) | 28 (65.1) | 16 (61.5) | 12 (70.6) | NS | 4/28 (14.3) | NS |
| Hospital-acquired BSI | 29 (67.4) | 16 (61.5) | 13 (76.5) | NS | 4/29 (13.8) | NS |
| MLHS (days) (mean ± S.D.) | 30.2 ± 22.8 | 27.5 ± 24.5 | 34.3 ± 19.9 | 0.174 | 18.5 ± 2.1 | NS |
| MLHS before BSI diagnosis (days) (mean ± S.D.) | 12.4 ± 16.1 | 10.2 ± 17.8 | 15.7 ± 12.9 | 0.139 | 3.7 ± 6.4 | NS |
| MLHS after the BSI (days) (mean ± S.D.) | 17.7 ± 13.7 | 17.5 ± 14.4 | 18.1 ± 13.1 | NS | 15.3 ± 4.7 | NS |
| Ward of hospitalisation | ||||||
| ICU | 5 (11.6) | 4 (15.4) | 1 (5.9) | NS e | – | NS e |
| Medicine | 22(51.2) | 12(46.2) | 10 (58.8) | 5/22 (22.7) | ||
| Surgery | 16 (37.2) | 10 (38.5) | 6 (35.3) | 1/16 (6.3) | ||
| Severity of septicaemia | ||||||
| Sepsis | 32 (74.4) | 21 (80.8) | 11 (64.7) | NSf | 3/32 (9.4) | 0.164f |
| Severe sepsis | 10 (23.3) | 5 (19.2) | 5 (29.4) | 2/10 (20.0) | ||
| Septic shock | 1(2.3) | – | 1(5.9) | 1/1 (100) | ||
| Predisposing factors | ||||||
| Bladder catheter | 23 (53.5) | 12 (46.2) | 11 (64.7) | NS | 3/23 (13.0) | NS |
| Intravascular catheter | 31 (72.1) | 16 (61.5) | 15 (88.2) | 0.085 | 4/31 (12.9) | NS |
| Previous use of antibiotics | 29 (67.4) | 16 (61.5) | 13 (76.5) | NS | 4/29 (13.8) | NS |
| AMC | 15 (34.9) | 8 (30.8) | 7 (41.2) | NS | 2/15 (13.3) | |
| 3GCs | 3 (7.0) | 1 (3.8) | 2 (11.8) | NS | 1/3 (33.3) | |
| TZP | 5(11.6) | 3 (11.5) | 2 (11.8) | NS | – | |
| Cefepime | 7 (16.3) | 3 (11.5) | 4 (23.5) | NS | 1/7 (14.3) | |
| Carbapenems | 4 (9.3) | 2 (7.7) | 2 (11.8) | NS | – | |
| Other β-lactams | 4 (9.3) | 2 (7.7) | 2 (11.8) | NS | – | |
| Quinolones | 5 (11.6) | 2 (7.7) | 3 (17.6) | NS | – | |
| Aminoglycosides | – | – | – | – | – | |
| Anti-Gram-positivesg | 10 (23.3) | 7 (26.9) | 3 (17.6) | NS | – | |
| Metronidazole | 5 (11.6) | 3 (11.5) | 2 (11.8) | NS | – | |
| Immunosuppressive therapy | 18 (41.9) | 12 (46.2) | 6 (35.3) | NS | 2/18 (11.1) | NS |
| Previous surgery | 15 (34.9) | 7 (26.9) | 8 (47.1) | NS | 2/15 (13.3) | NS |
| Biopsies | 4 (9.3) | 2 (7.7) | 2 (11.8) | NS | – | NS |
| Dialysis | 6 (14.0) | 2 (7.7) | 4 (23.5) | 0.193 | 1/6 (16.7) | NS |
| Parenteral feeding | 14(32.6) | 10(38.5) | 4(23.5) | NS | 2/14 (14.3) | NS |
| Drainages | 8 (18.6) | 4 (15.4) | 4 (23.5) | NS | 1/8 (12.5) | NS |
| Mechanical ventilation | 11 (25.6) | 8 (30.8) | 3 (17.6) | NS | 2/11 (18.2) | NS |
| Oesophagogastroscopy | 8 (18.6) | 4 (15.4) | 4 (23.5) | NS | 1/8 (12.5) | NS |
| Neutropenia | 13 (30.2) | 9 (34.6) | 4 (23.5) | NS | 1/13 (7.7) | NS |
| Overall secondary BSI (only if culture positive) | 8 (18.6) | 6 (23.1) | 2 (11.8) | NS | – | |
| Urinary tract | 6 (14.0) | 5 (19.2) | 1 (5.9) | NS | – | |
| Lower respiratory tract | – | – | – | NS | – | |
| Intravenous catheter | 3 (7.0) | 2 (7.7) | 1 (5.9) | NS | – | |
| eGFR prior the BSI episode | ||||||
| ≥90 mL/min | 22 (52.4)h | 16 (64.0) | 6 (35.3) | 0.115h | 1/22 (4.5) | 0.087h |
| 51–89 mL/min | 15 (35.7)h | 8 (32.0) | 7 (41.2) | 3/15 (20.0) | ||
| ≤50 mL/min | 5 (11.9)h | 1 (4.0) | 4 (23.5) | 2/5 (40.0) | ||
| eGFR during the BSI episode | ||||||
| ≥90 mL/min | 15 (34.9) | 11 (42.3) | 4 (23.5) | NSh | 2/15 (13.3) | NSh |
| 51–89 mL/min | 10 (23.3) | 7 (26.9) | 3 (17.6) | – | ||
| ≤50 mL/min | 18 (41.9) | 8 (30.8) | 10 (58.8) | 4/18 (22.2) | ||
| Empirical treatment provided | 42 (97.7) | 26 (100) | 16 (94.1) | NS | 5/42 (11.9) | 0.140 |
| Not adequate | 17 (39.5) | 9 (34.6) | 8 (47.1) | NSi | 3/17 (17.6) | NSi |
| AMC | 3 (7.0) | 2 (7.7) | 1 (5.9) | 1/3 (33.3) | ||
| 3GCs | 10 (23.3) | 7 (26.9) | 3 (17.6) | 1/10 (10.0) | ||
| TZP | 3 (7.0) | – | 3 (17.6) | 1/3 (33.3) | ||
| Cefepime | 1(2.3) | – | 1 (5.9) | – | ||
| Adequate | 25 (58.1) | 17 (65.4) | 8 (47.1) | 3/25 (12.0) | ||
| Cefepime | 17 (39.5) | 10 (38.5) | 7 (41.2) | 2/17 (11.8) | ||
| TZP | 1 (2.3) | 1 (3.8) | – | – | ||
| Carbapenems | 5 (11.6) | 4 (15.4) | 1 (5.9) | 1/5 (20.0) | ||
| Quinolones | 1 (2.3) | 1 (3.8) | – | – | ||
| Aminoglycosides | 1 (2.3) | 1 (3.8) | – | – | ||
| Treatment after ID/AST results (i.e. directed treatment) | ||||||
| Non-adequate | 8 (18.6) | 4 (15.4) | 4 (23.5) | NSi | 3/8 (37.5) | 0.067i |
| Adequate | 35 (81.4) | 22 (84.6) | 13 (76.5) | 3/35 (8.6) | ||
| 28-day mortality | 6(14.0) | 1 (3.8) | 5 (29.4) | 0.028 | NA | NA |
| Mortality attributable to BSI | 2 (4.7) | – | 2 (11.8) | 0.151 | NA | NA |
NA, not applicable; NS, not significant (results reported only when P ≤ 0.200); S.D., standard deviation; MLHS, mean length of hospital stay; ICU, Intensive Care Unit; AMC, amoxicillin/clavulanic acid; 3GC, third-generation cephalosporins; TZP, piperacillin/tazobactam; eGFR, estimated glomerular filtration rate; ID, identification; AST, antimicrobial susceptibility testing.
BSI cases initially due to Ind-Ecl but then evolving to Der-Ecl (5, 30 and p45) and those simultaneously having Ind-Ecl and Der-Ecl isolates (3, 26 and 31) were included only in the group of Der-Ecl.
Data are expressed as n (%) of patients unless otherwise indicated; – indicates n = 0.
One adult patient had two BSIs (4 and 43). Three paediatric patients (p41, p45 and p48/p49) were excluded; cases due to unidentified (34 and 35) and ESBL-Ecl (6 and 23) were also excluded.
Calculated as patients with non-fatal versus those with ultimately fatal plus rapidly fatal diseases.
Calculated as ICU versus non-ICU patients (i.e. those from medicine plus surgery).
Calculated as patients with sepsis versus those with severe sepsis and septic shock.
Includes vancomycin, clindamycin, daptomycin and flucloxacillin.
Calculated as patients with eGFR ≥90 mL/min versus those with eGFR <90 mL/min (data for one case due to Ind-Ecl were not available).
Calculated as cases receiving non-adequate versus those receiving adequate treatment.