Table 1.
Studies describing mortality in intensive care unit patients with infections caused by multi-drug resistant bacteria vs susceptible
| Ref. | Study design | No. of cases | Type of infection | Isolates/resistance definition | Results/comments |
| Blot et al[35] | Retrospective, cohort study | 328 | BSI | Variable/ceftazidime-resistance | Antibiotic resistance does not affect the outcome |
| Peres-Bota et al[36] | Prospective | 186 | Variable infections | Variable2/at least to ceftazidime, animoglycosides, carbapenems or quinolones | No difference in mortality |
| Ortega et al[37] | Single center prospective study | 53 | Colonization and infection | P. aeruginosa/resistant at least to two classes of antibiotics | No difference in mortality |
| Combes et al[38] | Secondary analysis of a large prospective cohort study | 115 | VAP | P. aeruginosa/resistance to piperacillin | 28-d mortality not associated with piperacillin resistance |
| Kwa et al[39] | Retrospective cohort study | 129 | VAP | Variable MDR bacteria/resistance to all available systemic antibiotics | MDR was associated with a higher likelihood of infection-attributed mortality |
| Playford et al[9] | Retrospective case-control study | 197 | Variable (including colonization) | A. baumannii/susceptible only to amikacin and colisin | Positive association with increased hospital mortality |
| Daniels et al[40] | Retrospective, propensity-matched cohort study | 84 | Variable infections | A. baumannii/resistance to 3 or more classes of antibiotics | No difference in 28-d mortality |
| Parker et al[41] | Secondary analysis of a randomized trial | 739 | VAP | P. aeruginosa or variable MDR bacteria2/resistance to 2 or more classes of antibiotics | Higher 28-d ICU and hospital mortality |
| Pinheiro et al[42] | Retrospective case–control study | 131 | Variable infections | P. aeruginosa/multi- or pandrug resistant | No association with mortality |
| Katsaragakis et al[43] | Prospective observational study in a surgical ICU | 60 | Variable infections | A. baumannii/susceptibility only to colistin | Multi- resistance not associated with mortality |
| Routsi et al[44] | Prospective observational study | 96 | BSI | A. baumannii/carbapenem resistance | No association with mortality |
| Mouloudi et al[45] | Double case -control study | 59 | BSI | K. pneumoniae/carbapenem resistance | Positive association between KPC producing K. pneumoniae and mortality |
| Michalopoulos et al[46] | Retrospective case-control study | 84 | Primary BSIs | K. pneumoniae, A. baumanni, P. aeruginosa/resistance to at least 4 out of 7 antibiotic classes | Higher hospital mortality, compared to controls |
| (78% ICU-acquired, 22% ward-acquired) | |||||
| Lambert et al[47] | Multicenter prospective cohort study | 119699 | Pneumonia, | E.coli, A. baumannii, P. aeruginosa, S. aureus/resistance to 3rd generation cephalosporins, ceftazidime, and oxacillin, respectively | The additional effect of the most common antimicrobial resistance patterns on mortality is comparatively low |
| Tabah et al[48] | Prospective multicentre cohort study | 1156 | BSI BSI | Multiple isolates2/according to the ESCMID | Resistance is associated with increased 28-d mortality |
| Patel et al[49] | Prospective cohort matched case- control | 298 | Variable infections | A. baumannii, K. pneumoniae, P. aeruginosa/susceptible to ≤ 1 antimicrobial agent | Resistance not associated with mortality |
| Zilberberg et al[50] | Single center retrospective cohort study | 1076 | BSI | Variable gram-negative/Paeruginosa resistant to at least 3 antimicrobials, ESBL, CPE | Impact of MDR on inappropriate therapy/indirect effect on increased hospital mortality |
| Shorr et al[51] | Retrospective cohort study | 131 | BSI | A. baumannii/carbapenem resistance | Impact of carbapenem resistance on inappropriate therapy/indirect effect on mortality |
| Papadimitriou–Olivgeris et al[52] | Single center study | 273 | Variable infections | K. pneumoniae/resistance to gentamicin, colistin and/or tigecycline | Positive association with mortality |
| Dabar et al[53] | 3-center, prospective cohort study | 120 | Variable infections | Variable pathogens/MDR P. aeruginosa: Resistance to at least 3 of the following: Pseudomonas acting beta-lactams, carbapenems, aminoglycosides, and quinolones | MDR P. aeruginosa infection was independent risk factor for mortality |
| Dautzenberg et al[30]1 | 2-center prospective cohort study | 132 | Colonization | CPE | Higher hazard of dying (primarily because of an increased LOS) |
| Bass et al[54] | Prospective case-control study | 168 | BSI | Gram-negative bacteria/carbapenem resistance | Increased mortality/combination therapy was associated with improve survival rate |
| Vardakas et al[55] | Retrospective | 140 | Variable infections | K. pneumonia/carbapenem resistance | No difference in mortality |
| Cohort study | |||||
| Martin-Loeches et al[56] | Prospective observetional study | VAP and HAP | Variable/according to CDC/ECDC | Patients with MDR bacteria had a higher mortality than those with no-MDR |
1
Colonization only;
2
Gram–positive included. BSI: Blood stream infection; VAP: Ventilator associated pneumonia; MDR: Multidrug-resistant; ESCMID: European Society of Clinical Microbiology and Infectious Diseases; CPE: Carbapenem – producing enterobactaeriacae; ESBL: Extended spectrum beta lactamases; HAP: Hospital acquired pneumonia; ECDC: European Centre for Disease Prevention and Control; CDC: Centers for Disease Control and Prevention.