The association between colonization with carbapenemase-producing enterobacteriaceae and overall ICU mortality: an observational cohort study.

OBJECTIVES: Infections caused by carbapenemase-producing Enterobacteriaceae are increasing worldwide, especially in ICUs, and have been associated with high mortality rates. However, unequivocally demonstrating causality of such infections to death is difficult in critically ill patients because of potential confounding and competing events. Here, we quantified the effects of carbapenemase-producing Enterobacteriaceae carriage on patient outcome in two Greek ICUs with carbapenemase-producing Enterobacteriaceae endemicity. DESIGN: Observational cohort study. SETTING: Two ICUs with carbapenemase-producing Enterobacteriaceae endemicity. PATIENTS: Patients admitted to the ICU with an expected length of ICU stay of at least 3 days were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Carbapenemase-producing Enterobacteriaceae colonization was established through screening in perineum swabs obtained at admission and twice weekly and inoculated on chromogenic plates. Detection of carbapenemases was performed phenotypically, with confirmation by polymerase chain reaction. Risk factors for ICU mortality were evaluated using cause-specific hazard ratios and subdistribution hazard ratios, with carbapenemase-producing Enterobacteriaceae colonization as time-varying covariate. One thousand seven patients were included, 36 (3.6%) were colonized at admission, and 96 (9.5%) acquired carbapenemase-producing Enterobacteriaceae colonization during ICU stay, and 301 (29.9%) died in ICU. Of 132 carbapenemase-producing Enterobacteriaceae isolates, 125 (94.7%) were Klebsiella pneumoniae and 74 harbored K. pneumoniae carbapenemase (56.1%), 54 metallo-ß-lactamase (40.9%), and four both (3.0%). Carbapenemase-producing Enterobacteriaceae colonization was associated with a statistically significant increase of the subdistribution hazard ratio for ICU mortality (subdistribution hazard ratio=1.79; 95% CI, 1.31-2.43), not explained by an increased daily hazard of dying (cause-specific hazard ratio for death=1.02; 95% CI, 0.74-1.41), but by an increased length of stay (cause-specific hazard ratio for discharge alive=0.73; 95% CI, 0.51-0.94). Other risk factors in the subdistribution hazard model were Acute Physiology and Chronic Health Evaluation II score (subdistribution hazard ratio=1.13; 95% CI, 1.11-1.15), female gender (subdistribution hazard ratio=1.29; 95% CI, 1.02-1.62), presence of solid tumor (subdistribution hazard ratio=1.54; 95% CI, 1.15-2.06), hematopoietic malignancy (subdistribution hazard ratio=1.61; 95% CI, 1.04-2.51), and immunodeficiency (subdistribution hazard ratio=1.59; 95% CI, 1.11-2.27). CONCLUSIONS: Patients colonized with carbapenemase-producing Enterobacteriaceae have on average a 1.79 times higher hazard of dying in ICU than noncolonized patients, primarily because of an increased length of stay.

Interventions to reduce colonisation and transmission of antimicrobial-resistant bacteria in intensive care units: an interrupted time series study and cluster randomised trial.

BACKGROUND: Intensive care units (ICUs) are high-risk areas for transmission of antimicrobial-resistant bacteria, but no controlled study has tested the effect of rapid screening and isolation of carriers on transmission in settings with best-standard precautions. We assessed interventions to reduce colonisation and transmission of antimicrobial-resistant bacteria in European ICUs. METHODS: We did this study in three phases at 13 ICUs. After a 6 month baseline period (phase 1), we did an interrupted time series study of universal chlorhexidine body-washing combined with hand hygiene improvement for 6 months (phase 2), followed by a 12-15 month cluster randomised trial (phase 3). ICUs were randomly assigned by computer generated randomisation schedule to either conventional screening (chromogenic screening for meticillin-resistant Staphylococcus aureus [MRSA] and vancomycin-resistant enterococci [VRE]) or rapid screening (PCR testing for MRSA and VRE and chromogenic screening for highly resistant Enterobacteriaceae [HRE]); with contact precautions for identified carriers. The primary outcome was acquisition of resistant bacteria per 100 patient-days at risk, for which we calculated step changes and changes in trends after the introduction of each intervention. We assessed acquisition by microbiological surveillance and analysed it with a multilevel Poisson segmented regression model. We compared screening groups with a likelihood ratio test that combined step changes and changes to trend. This study is registered with ClinicalTrials.gov, number NCT00976638. FINDINGS: Seven ICUs were assigned to rapid screening and six to conventional screening. Mean hand hygiene compliance improved from 52% in phase 1 to 69% in phase 2, and 77% in phase 3. Median proportions of patients receiving chlorhexidine body-washing increased from 0% to 100% at the start of phase 2. For trends in acquisition of antimicrobial-resistant bacteria, weekly incidence rate ratio (IRR) was 0·976 (0·954-0·999) for phase 2 and 1·015 (0·998-1·032) for phase 3. For step changes, weekly IRR was 0·955 (0·676-1·348) for phase 2 and 0·634 (0·349-1·153) for phase 3. The decrease in trend in phase 2 was largely caused by changes in acquisition of MRSA (weekly IRR 0·925, 95% CI 0·890-0·962). Acquisition was lower in the conventional screening group than in the rapid screening group, but did not differ significantly (p=0·06). INTERPRETATION: Improved hand hygiene plus unit-wide chlorhexidine body-washing reduced acquisition of antimicrobial-resistant bacteria, particularly MRSA. In the context of a sustained high level of compliance to hand hygiene and chlorhexidine bathings, screening and isolation of carriers do not reduce acquisition rates of multidrug-resistant bacteria, whether or not screening is done with rapid testing or conventional testing. FUNDING: European Commission.

Diagnosis and treatment of mucormycosis in patients with hematological malignancies: guidelines from the 3rd European Conference on Infections in Leukemia (ECIL 3).

Mucormycosis is an emerging cause of infectious morbidity and mortality in patients with hematologic malignancies. However, there are no recommendations to guide diagnosis and management. The European Conference on Infections in Leukemia assigned experts in hematology and infectious diseases to develop evidence-based recommendations for the diagnosis and treatment of mucormycosis. The guidelines were developed using the evidence criteria set forth by the American Infectious Diseases Society and the key recommendations are summarized here. In the absence of validated biomarkers, the diagnosis of mucormycosis relies on histology and/or detection of the organism by culture from involved sites with identification of the isolate at the species level (no grading). Antifungal chemotherapy, control of the underlying predisposing condition, and surgery are the cornerstones of management (level A II). Options for first-line chemotherapy of mucormycosis include liposomal amphotericin B and amphotericin B lipid complex (level B II). Posaconazole and combination therapy of liposomal amphotericin B or amphotericin B lipid complex with caspofungin are the options for second line-treatment (level B II). Surgery is recommended for rhinocerebral and skin and soft tissue disease (level A II). Reversal of underlying risk factors (diabetes control, reversal of neutropenia, discontinuation/taper of glucocorticosteroids, reduction of immunosuppressants, discontinuation of deferroxamine) is important in the treatment of mucormycosis (level A II). The duration of antifungal chemotherapy is not defined but guided by the resolution of all associated symptoms and findings (no grading). Maintenance therapy/secondary prophylaxis must be considered in persistently immunocompromised patients (no grading).

Incidence and risk factors for central vascular catheter-related bloodstream infections in a tertiary care hospital.

This study evaluated the incidence of colonization and infection related to Central Vascular Catheters (CVC) in a tertiary care Greek hospital, as well as risk factors associated with catheter-related bloodstream infection (CRBSI). A total of 340 CVCs, were studied in relation to patient clinical and epidemiological data, CVC characteristics, and microbiological culture results. Risk factors were assessed. Pulsed field gel electrophoresis was used for the investigation of the clonal relationship of the isolates. The incidence for CRBSI and catheter colonization (CC) was 11.47 and 19.49 per 1,000 catheter days, respectively. Risk factors independently associated with CRBSI were use of corticosteroids, diabetes mellitus, solid organ neoplasm, long duration of catheterization, and changing the CVC dressing at intervals of 48 hours or more. Risk factors for CC were diabetes mellitus, hospitalization in ICU, and prolonged hospitalization. The predominant microorganisms isolated from CRBSI episodes were coagulase-negative staphylococci. All patients with CVC require constant infection surveillance and appropriate care by trained medical staff. Use of CVC for the shortest time possible, good hand hygiene and change of CVC dressing at intervals of less than 48 hours are infection prevention practices that need to be followed.