Evaluating all inpatient carbapenem-resistant Enterobacteriaceae (CRE) infections over a 1-year period, 47% were caused by carbapenemase-producing (CP) organisms. Compared with non-CP-CRE patients, patients with CP-CRE had an 18-fold greater odds of a recent stay in a foreign health care facility and a 3-fold greater odds of transfer from a post-acute care facility.

Evidence on pharmacokinetic/pharmacodynamic (PK/PD) alterations and clinical outcomes in obese patients with serious infections remains limited. This study aimed to evaluate predicted PK/PD indices of efficacy and observed clinical outcomes between obese and nonobese patients receiving cefepime or piperacillin-tazobactam for Enterobacteriaceae bacteremia.

This study quantified mortality associated with serious infections caused by carbapenem-resistant (CRE) and carbapenem-susceptible Enterobacteriaceae (CSE). A systematic literature review was conducted, evaluating outcomes in hospitalized patients with CRE infections from a blood, urinary, pulmonary, or intra-abdominal source. A meta-analysis (MA) calculating odds ratios (ORs) for mortality was performed. Twenty-two studies met the criteria for inclusion in the MA: 12 included mortality data for CRE vs CSE populations. Compared with CSE, CRE was associated with a significantly higher risk of overall mortality (OR, 3.39; 95% confidence interval [CI], 2.35-4.89), as was monotherapy (vs combination therapy) treatment of patients with CRE infections (OR, 2.19; 95% CI, 1.00-4.80). These results document the increased mortality associated with serious CRE infections compared with CSE infections among hospitalized adults. It will be important to reevaluate the mortality in CRE and CSE populations, especially among patients who receive early appropriate therapy, as new antibiotics become available.

Carbapenems are widely used for the management of bloodstream infections (BSIs) caused by extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE). However, the wide use of carbapenems has been associated with carbapenem-resistant Enterobacteriaceae development.

The role of cefepime for extended-spectrum β-lactamase (ESBL) bacteremia is unclear if susceptible in vitro. In a propensity score-matched study of patients with ESBL bacteremia, risk of death was 2.87 times higher for patients receiving cefepime compared with carbapenems (95% confidence interval [CI], .88-9.41). We compared 14-day mortality of patients with ESBL bacteremia receiving empiric cefepime versus empiric carbapenem therapy in a propensity score-matched cohort. There was a trend towards increased mortality in the cefepime group (hazard ratio, 2.87; 95% CI, .88-9.41), which enhances the existing literature suggesting that cefepime may be suboptimal for invasive ESBL infections.

Using published data, we sought to compare outcomes in patients transitioned to either oral fluoroquinolones (FQ) or trimethoprim-sulfamethoxazole (TMP-SMX) versus ß-lactams (BL's) after an initial intravenous (IV) course for gram-negative rod (GNR) bacteremia.

There is increasing demand for compounds to treat antimicrobial-resistant pathogens, and essential oils have gained interest. Moreover, previous studies have demonstrated antimicrobial activity of these nonpharmaceutical products. We investigated the activity of essential oils against multiresistant bacteria and other clinical isolates to evaluate the potential of their use topically and/or internally for treatment of bacterial infections.

Piperacillin-tazobactam-nonsusceptible (TZP-NS) Enterobacteriaceae are typically also resistant to ceftriaxone. We recently encountered bacteremias due to Escherichia coli (Ec) and Klebsiella pneumoniae (Kp) that were TZP-NS but ceftriaxone-susceptible (CRO-S).

In a multicenter study from Taiwan, we aimed to investigate the outcome of patients who received different antimicrobial therapy in carbapenem-resistant Enterobacteriaceae bloodstream infections and proposed a new definition for tigecycline use.

Background.  Carbapenem-resistant Enterobacteriaceae has increased dramatically in the last decade, resulting in infections that are difficult to treat and associated with high mortality rates. To prevent further antibacterial resistance, it is necessary to use carbapenem selectively. A combination of metronidazole with an antimicrobial agent active against aerobes is an alternative effective treatment for patients with complicated intra-abdominal infections (cIAIs). This study aimed to compare efficacy and safety of metronidazole combination therapies and carbapenem and to provide clinical evidence regarding the optimal treatment of cIAI. Methods.  A systematic review and a meta-analysis of randomized clinical trials in the treatment of cIAI were conducted. The systematic review with PubMed, Embase, and the Cochrane Database of Systematic Reviews followed the Cochrane Handbook's recommended methodology, and the meta-analysis used a Mantel-Haenszel random-effects model with RevMan, version 5.3. Primary endpoints were clinical success and bacteriological eradication, and secondary endpoints were all-cause mortality and drug-related adverse events. Results.  Eight studies comparing metronidazole combination therapies and carbapenem were included in the meta-analysis. No difference was found between combined therapy with metronidazole and carbapenem regarding clinical success (odds ratio [OR] = 1.31; 95% confidence interval [CI], .75-2.31), bacteriological eradication (OR = 1.27; 95% CI, .84-1.91), all-cause mortality (OR = 0.61; 95% CI, .37-1.00), or drug-related adverse events (OR = 0.58; 95% CI, .18-1.88). Sensitivity analyses found similar results. Conclusions.  Combined therapy with metronidazole is as effective and safe as carbapenem in treatment of cIAI. Therefore, combined therapy with metronidazole offers an effective alternative to carbapenem with low risk of drug resistance.

In 2010, the Clinical Laboratory and Standards Institute recommended a 3-fold lowering of ceftriaxone breakpoints to 1 mcg/mL for Enterobacteriaceae. Supportive clinical data at the time were from fewer than 50 patients. We compared the clinical outcomes of adults with Enterobacteriaceae bloodstream infections treated with ceftriaxone compared with matched patients (with exact matching on ceftriaxone minimum inhibitory concentrations [MICs]) treated with extended-spectrum agents to determine if ceftriaxone breakpoints could be increased without negatively impacting patient outcomes.

The optimal treatment for potential AmpC-producing Enterobacteriaceae, including Serratia, Providencia, Citrobacter, Enterobacter, and Morganella species, remains unknown. An updated systematic review and meta-analysis of studies comparing beta-lactam/beta-lactamase inhibitors with carbapenems in the treatment of bloodstream infections with these pathogens found no significant difference in 30-day mortality (OR, 1.13; 95% CI, 0.58 - 2.20).

Metagenomic next-generation sequencing (mNGS) provides innovative solutions for predicting complex infections. A comprehensive understanding of its strengths and limitations in real-world clinical settings is necessary to ensure that it is not overused or misinterpreted.