Related Experiment Video
Updated: Mar 8, 2026
Recurrent Escherichia coli Urinary Tract Infection Triggered by Gardnerella vaginalis Bladder Exposure in Mice
Published on: December 4, 2020
Risk factors for relapse or persistence of bacteraemia caused by Enterobacter spp.: a case-control study
Patrick N A Harris1, Anna M Peri2, Anita M Pelecanos3
1University of Queensland, UQ Centre for Clinical Research, Royal Brisbane and Women's Hospital, Building 71/918 Royal Brisbane & Women's Hospital Campus, 4029 Herston, QLD Australia.
Background:
Enterobacter spp. possess chromosomal AmpC beta-lactamases that may be expressed at high levels. Previous studies have demonstrated a risk of relapsed bacteraemia following therapy with third generation cephalosporins (3GCs). What additional factors predict microbiological failure in Enterobacter bacteraemia is unclear. We aimed to determine factors associated with microbiological failure in Enterobacter bacteraemia.
Methods:
We retrospectively identified cases of bacteraemia caused by Enterobacter spp. occurring in four hospitals. Using a case-control design, we determined clinical risk factors for persistence or relapse defined as repeated positive blood cultures collected between 72 hours and up to 28 days post initial positive blood culture.
Results:
During the study period a total of 922 bacteraemia events caused by Enterobacter spp. in adults were identified. The overall risk of relapsed or persisting bacteraemia at 28 days was low (31 of 922, 3.4%), with only 2 patients experiencing emergent resistance to 3GCs. A total of 159 patients were included in the case-control study. Using multivariate logistic regression, independent predictors for relapse were a line-associated source of infection (OR 3.87; 95% CI 1.56-9.60, p = 0.004) and the presence of immunosuppression (OR 2.70; 95% CI 1.14-6.44, p = 0.02). On univariate analysis definitive therapy with a broad-spectrum beta-lactam-beta-lactamase inhibitor (BLBLI, e.g. piperacillin-tazobactam) was not associated with relapse (OR 1.83; 95% CI 0.64-5.21, p = 0.26) although the proportion of patients receiving a BLBLI as definitive therapy was relatively small (21/159, 13.2%).
Conclusions:
The risk of relapsed or persistent Enterobacter bacteraemia appears to be low in Australia. A line-associated source of infection and immunocompromise were significant independent predictors for relapse. Larger, preferably randomized, studies are needed to address whether BLBLIs represent an effective carbapenem-sparing option for Enterobacter bacteraemia.
Insights
Relapsed Enterobacter bacteraemia is uncommon. Risk factors for relapse include line-associated infections and immunosuppression, guiding future treatment strategies for this common bloodstream infection.
Area of Science:
- Infectious Diseases
- Clinical Microbiology
- Antimicrobial Resistance
Background:
- Enterobacter species possess AmpC beta-lactamases, potentially leading to high-level expression.
- Previous research indicates a risk of relapsed bacteraemia after third-generation cephalosporin (3GC) therapy.
- Factors predicting microbiological failure in Enterobacter bacteraemia require further clarification.
Purpose of the Study:
- To identify clinical factors associated with microbiological failure in patients with Enterobacter bacteraemia.
- To investigate predictors of persistent or relapsed Enterobacter bacteraemia.
Main Methods:
- Retrospective case-control study of Enterobacter bacteraemia cases across four hospitals.
- Defined microbiological failure as repeated positive blood cultures within 28 days of initial detection.
- Utilized multivariate logistic regression to identify independent risk factors.
Main Results:
- The overall risk of relapsed or persistent Enterobacter bacteraemia was low (3.4%).
- Independent predictors for relapse included line-associated infection (OR 3.87) and immunosuppression (OR 2.70).
- Emergent resistance to 3GCs was rare (2/922 patients).
Conclusions:
- Relapsed or persistent Enterobacter bacteraemia is infrequent in Australia.
- Line-associated infection and immunocompromise are significant predictors of relapse.
- Further research, including randomized trials, is needed to evaluate broad-spectrum beta-lactam-beta-lactamase inhibitors (BLBLIs) as a carbapenem-sparing option.
More Related Videos
07:25High-throughput Screening of Chemical Compounds to Elucidate Their Effects on Bacterial Persistence
Published on: February 23, 2021
07:44Time-Lapse Epifluorescence Microscopy Imaging of Pseudomonas aeruginosa and Staphylococcus aureus Heterogeneous Phenotypes
Published on: February 14, 2025
Related Concept Videos
01:30Development of Antibiotic Resistance
01:26Factors Affecting the Risk of Infection
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin...
01:26Healthcare Associated Infections I: Iatrogenic, Exogenic and Endogenic
HAIs significantly increase the cost of health care. Extended stays in healthcare institutions, increased disability, increased costs of medications, including specialized antibiotics, and prolonged recovery times add to the patient's expenses and the healthcare institution and funding bodies.
01:25Urinary Tract Infection II: Pathophysiology
01:22Healthcare Associated Infections II: Preventive Measures
The best practices for preventing healthcare-associated infections include hand hygiene, patient risk...
01:20Infection
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...