Effect of a dietary supplement composed of hydrolyzed milk proteins and vanillin on the reduction of infection and oxidative stress induced by chemotherapy

This study evaluates the antioxidant and antibacterial activity of a mixture of lactoferrin hydrolysate (LfH), whey protein hydrolysate (WPH) and vanillin in vitro and in vivo to design a chemoprotective supplement for reducing the infection and oxidative stress induced by chemotherapy. The designed supplement showed significant antibacterial activity against E. coli. The supplement with the highest concentration exhibited considerable antioxidant activity in (2,2-diphenyl-1-picrylhydrazyl) DPPH free radicals, (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) ABTS, and reducing power assays. In the biochemical analysis of liver homogenate, the supplement 3 increased the level of enzymes Catalase (CAT), Glutathione peroxidase (GPx), Superoxide dismutase (SOD), and also the Ferric Reducing Ability of Plasma (FRAP) while decreased thiobarbituric acid reactive substances (TBARS) in comparison to paclitaxel group, indicative of activity against oxidative stress. Antibacterial and antioxidant activity of the designed supplement makes it a good candidate for use as a functional food to reduce the side effects of chemotherapy. PRACTICAL APPLICATIONS: A dietary supplement composed of lactoferrin hydrolysate (LfH), whey protein hydrolysate (WPH) and vanillin showed antibacterial activity against E. coli and S. aureus in vitro. The studied supplement also exhibited significant antioxidant properties in the model system and anti-oxidative stress activity in mice exposed to paclitaxel. This supplement has a potential for use in the food matrix to reduce the chemotherapy side effects and to act as a chemoprotective agent.

Factors favouring the evolution of multidrug resistance in bacteria

The evolution of multidrug antibiotic resistance in commensal bacteria is an important public health concern. Commensal bacteria such as Escherichia coli, Streptococcus pneumoniae or Staphylococcus aureus, are also opportunistic pathogens causing a large fraction of the community-acquired and hospital-acquired bacterial infections. Multidrug resistance (MDR) makes these infections harder to treat with antibiotics and may thus cause substantial additional morbidity and mortality. Here, we develop an evolutionary epidemiology model to identify the factors favouring the evolution of MDR in commensal bacteria. The model describes the evolution of antibiotic resistance in a commensal bacterial species evolving in a host population subjected to multiple antibiotic treatments. We combine statistical analysis of a large number of simulations and mathematical analysis to understand the model behaviour. We find that MDR evolves more readily when it is less costly than expected from the combinations of single resistances (positive epistasis). MDR frequently evolves when bacteria are in contact with multiple drugs prescribed in the host population, even if individual hosts are only treated with a single drug at a time. MDR is favoured when the host population is structured in different classes that vary in their rates of antibiotic treatment. However, under most circumstances, recombination between loci involved in resistance does not meaningfully affect the equilibrium frequency of MDR. Together, these results suggest that MDR is a frequent evolutionary outcome in commensal bacteria that encounter the variety of antibiotics prescribed in the host population. A better characterization of the variability in antibiotic use across the host population (e.g. across age classes or geographical location) would help predict which MDR genotypes will most readily evolve.

Nosocomial infections due to multidrug-resistant bacteria in cancer patients: a six-year retrospective study of an oncology Center in Western China

BACKGROUND

Bacterial infections are the most frequent complications in patients with malignancy, and the epidemiology of nosocomial infections among cancer patients has changed over time. This study aimed to evaluate the characteristics, antibiotic resistance patterns, and prognosis of nosocomial infections due to multidrug-resistant (MDR) bacteria in cancer patients.

METHODS

This retrospective observational study analyzed cancer patients with nosocomial infections caused by MDR from August 2013 to May 2019. The extracted clinical data were recorded in a standardized form and compared based on the survival status of the patients after infection and during hospitalization. The data were analyzed using independent samples t-test, Chi-square test, and binary logistic regression. P-values < 0.05 were considered significant.

RESULTS

One thousand eight patients developed nosocomial infections during hospitalization, with MDR strains detected in 257 patients. Urinary tract infection (38.1%), respiratory tract infection (26.8%), and bloodstream infection (BSI) (12.5%) were the most common infection types. Extended-spectrum β-lactamase producing Enterobacteriaceae (ESBL-PE) (72.8%) members were the most frequently isolated MDR strains, followed by Acinetobacter baumannii (11.7%), and Stenotrophomonas maltophilia (6.2%). The results of multivariate regression analysis revealed that smoking history, intrapleural/abdominal infusion history within 30 days, the presence of an indwelling urinary catheter, length of hospitalization, and hemoglobin were independent factors for in-hospital mortality in the study population. The isolated MDR bacteria exhibited high rates of sensitivity to amikacin, meropenem, and imipenem.

CONCLUSIONS

The burden of nosocomial infections due to MDR bacteria is considerably high in oncological patients, with ESBL-PE being the most predominant causative pathogen. Our findings suggest that amikacin and carbapenems actively against more than 89.7% of MDR isolates. The precise management of MDR bacterial infections in cancer patients may improve the prognosis of these individuals.

Prevalence of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae Causing Bloodstream Infections in Cancer Patients from Southwest of Iran

Introduction

This study aimed to evaluate the frequency rate of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) causing bloodstream infections (BSIs) in cancer patients referred to one of the major referral hospitals in Ahvaz city, southwest Iran.

Materials and Methods

In this study, 1700 blood cultures were collected from 610 cancer patients suspected to have BSI from October 2016 to August 2017 referred to the Shafa cancer hospital, Ahvaz, southwest of Iran. The blood culture bottles were incubated aerobically at 35-37ºC for 24 hours and then sub-cultured on routine microbiology culture media. The bacterial colonies were identified using standard tests. The antibiotic susceptibility testing was achieved by the disc-diffusion method. The phenotypic detection of ESBLs was carried out by the combination disc-diffusion test (CDDT). Finally, the polymerase chain reaction (PCR) was performed to investigate the presence of bla _TEM, bla _CTX, bla _SHV, and bla _PER genes.

Results

The prevalence of BSI in cancer patients was 16.4% (100/610). Gram-negative rods with rate of 74% (74/100) were the most prevalent bacteria. The frequency of Enterobacteriaceae family was 21% including Escherichia coli (n: 8), Klebsiella pneumoniae (n: 6), Enterobacter spp. (n: 5), Citrobacter freundii (n: 1), and Serratia marcescens (n: 1). All isolates were multidrug-resistant (resistance to three or more antibiotics). The results of CDDT showed that 42.8% (9/21) of Enterobacteriaceae isolates had a positive ESBL test of which 100% (9/9) indicated positive band for at least one of the ESBL genes by PCR method. The bla _CTX-M and bla _TEM genes were detected in 38% (8/21) and 23.8% (5/21) of isolates, respectively, while the bla _SHV and bla _PER were not detected in any isolates.

Conclusion

Based on the results, surveillance, and antibiotic stewardship programs should be implemented for cancer patients to prevent the spread of more ESBL-PE that have limited therapeutically choices.

Multicenter Evaluation of the BD Phoenix CPO Detect Test for Detection and Classification of Carbapenemase-Producing Organisms in Clinical Isolates

Limited treatment options contribute to high morbidity/mortality rates with carbapenem-resistant, Gram-negative bacterial infections. New approaches for carbapenemase-producing organism (CPO) detection may help inform clinician decision-making on patient treatment and infection control. BD Phoenix CPO detect (CPO detect) detects and classifies carbapenemases in Enterobacterales, Acinetobacter baumannii, and Pseudomonas aeruginosa during susceptibility testing.

Limited treatment options contribute to high morbidity/mortality rates with carbapenem-resistant, Gram-negative bacterial infections. New approaches for carbapenemase-producing organism (CPO) detection may help inform clinician decision-making on patient treatment and infection control. BD Phoenix CPO detect (CPO detect) detects and classifies carbapenemases in Enterobacterales, Acinetobacter baumannii, and Pseudomonas aeruginosa during susceptibility testing. The clinical performance of CPO detect is reported here. Enterobacterales, Acinetobacter baumannii, and Pseudomonas aeruginosa isolates were evaluated across three sites using CPO detect and a composite reference method (RM); the latter was comprised of the modified carbapenem inactivation method and a MIC screen for ertapenem, imipenem, and meropenem. Multiplex PCR testing was also utilized for Ambler class determination. Positive and negative percentages of agreement (PPA and NPA, respectively) between CPO detect and the RM were determined. The PPA and NPA for Enterobacterales were 98.5% (confidence intervals, 96.6%, 99.4%) and 97.2% (95.8%, 98.2%), respectively. The A. baumannii PPA and NPA, respectively, were 97.1% (90.2%, 99.2%) and 97.1% (89.9%, 99.2%). The P. aeruginosa PPA and NPA, respectively, were 95.9% (88.6%, 98.6%) and 92.3% (86.7%, 95.6%). The PPA values for carbapenemase class designations for all organisms combined and Enterobacterales alone, respectively, were 95.3% (90.2%, 97.8%) and 94.6% (88.8%, 97.5%) for class A, 94.0% (88.7%, 96.6%) and 96.4% (90.0%, 98.8%) for class B, and 95.0% (90.1%, 97.6%) and 99.0% (94.4%, 99.8%) for class D carbapenemases. NPA values for all organisms and Enterobacterales alone ranged from 98.5% to 100%. CPO detect provided accurate detection and classification of CPOs for the majority of isolates of Enterobacterales, Acinetobacter baumannii, and Pseudomonas aeruginosa tested.

Combating antibiotic resistance using guidelines and enhanced stewardship in Kenya: a protocol for an implementation science approach

INTRODUCTION

Antimicrobial resistance (AMR) is a growing problem globally especially in Sub-Saharan Africa including Kenya. Without any intervention, lower/middle-income countries (LMICs) will be most affected due to already higher AMR levels compared with higher income countries and due to the far higher burden of diseases in the LMICs. Studies have consistently shown that inappropriate use of antimicrobials is the major driver of AMR. To address this challenge, hospitals are now implementing antibiotic stewardship programmes (ASPs), which have been shown to achieve reduced antibiotic usage, to decrease the prevalence of resistance and lead to significant economic benefits. However, the implementation of the guideline is highly dependent on the settings in which they are rolled out. This study, employing an implementation science approach, aims to address the knowledge gap in this area and provide critical data as well as practical experiences when using antibiotic guidelines and stewardship programmes in the public health sector. This will provide evidence of ASP performance and potentially contribute to the county, national and regional policies on antibiotics use.

METHODS AND ANALYSIS

The study will be conducted in three geographically diverse regions, each represented by two hospitals. A baseline study on antibiotic usage, resistance and de-escalation, duration of hospital stay, rates of readmission and costs will be carried out in the preimplementation phase. The intervention, that is, the use of antibiotic guidelines and ASPs will be instituted for 18 months using a stepwise implementation strategy that will facilitate learning and continuous improvement of stewardship activities and updating of guidelines to reflect the evolving antibiotic needs.

ETHICS AND DISSEMINATION

Approvals to carry out the study have been obtained from the National Commission for Science, Technology and Innovation and the Mount Kenya University Ethics Review Committee. The approvals from the two institutions were used to obtain permission to conduct the study at each of the participating hospitals. Study findings will be presented to policy stakeholders and published in peer-reviewed scientific journals. It is anticipated that the findings will inform the appropriate antibiotic use guidelines within our local context.

Clinical Predictive Model of Multidrug Resistance in Neutropenic Cancer Patients with Bloodstream Infection Due to Pseudomonas aeruginosa

We aimed to assess the rate and predictive factors of bloodstream infection (BSI) due to multidrug-resistant (MDR) Pseudomonas aeruginosa in neutropenic cancer patients. We performed a multicenter, retrospective cohort study including oncohematological neutropenic patients with BSI due to P. aeruginosa conducted across 34 centers in 12 countries from January 2006 to May 2018. A mixed logistic regression model was used to estimate a model to predict the multidrug resistance of the causative pathogens. Of a total of 1,217 episodes of BSI due to P. aeruginosa, 309 episodes (25.4%) were caused by MDR strains. The rate of multidrug resistance increased significantly over the study period (P = 0.033). Predictors of MDR P. aeruginosa BSI were prior therapy with piperacillin-tazobactam (odds ratio [OR], 3.48; 95% confidence interval [CI], 2.29 to 5.30), prior antipseudomonal carbapenem use (OR, 2.53; 95% CI, 1.65 to 3.87), fluoroquinolone prophylaxis (OR, 2.99; 95% CI, 1.92 to 4.64), underlying hematological disease (OR, 2.09; 95% CI, 1.26 to 3.44), and the presence of a urinary catheter (OR, 2.54; 95% CI, 1.65 to 3.91), whereas older age (OR, 0.98; 95% CI, 0.97 to 0.99) was found to be protective. Our prediction model achieves good discrimination and calibration, thereby identifying neutropenic patients at higher risk of BSI due to MDR P. aeruginosa The application of this model using a web-based calculator may be a simple strategy to identify high-risk patients who may benefit from the early administration of broad-spectrum antibiotic coverage against MDR strains according to the local susceptibility patterns, thus avoiding the use of broad-spectrum antibiotics in patients at a low risk of resistance development.

Sepsis in cancer patients residing in Zimbabwe: spectrum of bacterial and fungal aetiologies and their antimicrobial susceptibility patterns

Background

Cancer and sepsis comorbidity is a major public health problem in most parts of the world including Zimbabwe. The microbial aetiologies of sepsis and their antibiograms vary with time and locations. Knowledge on local microbial aetiologies of sepsis and their susceptibility patterns is critical in guiding empirical antimicrobial treatment choices.

Methods

This was a descriptive cross-sectional study which determined the microbial aetiologies of sepsis from blood cultures of paediatric and adult cancer patients obtained between July 2016 and June 2017. The TDR-X120 blood culture system and TDR 300B auto identification machine were used for incubation of blood culture bottles and identification plus antimicrobial susceptibility testing, respectively.

Results

A total of 142 participants were enrolled; 50 (35.2%) had positive blood cultures, with 56.0% Gram positive, 42.0% Gram-negative bacteria and 2.0% yeast isolated. Common species isolated included coagulase negative Staphylococcus spp. (CoNS) (22.0%), E. coli (16.0%), K. pneumoniae (14.0%), E. faecalis (14.0%) and S. aureus (8.0%). Gram-negative isolates exhibited high resistance to gentamicin (61.9%) and ceftriaxone (71.4%) which are the empiric antimicrobial agents used in our setting. Amikacin and meropenem showed 85.7 and 95.2% activity respectively against all Gram-negative isolates, whilst vancomycin and linezolid were effective against 96.2 and 100.0% of all Gram-positive isolates respectively. We isolated 10 (66.7%) extended spectrum β-lactamase (ESBL) amongst the E. coli and K. pneumoniae isolates. Ten (66.7%) of the Staphylococcus spp. were methicillin resistant.

Conclusions

CoNS, E. coli, K. pneumoniae, E. faecalis and S. aureus were the major microbial drivers of sepsis amongst cancer patients in Zimbabwe. Most isolates were found to be resistant to commonly used empirical antibiotics, with isolates exhibiting high levels of ESBL and methicillin resistance carriage. A nationwide survey on microbial aetiologies of sepsis and their susceptibility patterns would assist in the guidance of effective sepsis empiric antimicrobial treatment among patients with cancer.

Clinical, laboratory features and prognosis of children receiving IgM-enriched immunoglobulin (3 days vs. 5 days) as adjuvant treatment for serious infectious disease in pediatric intensive care unit: a retrospective single-center experience (PIGMENT study)

Introduction

Although there are studies about sepsis treatment in different age groups, data on immunoglobulin-M (IgM)-enriched intravenous immunoglobulin use in pediatric intensive care units (PICUs) are limited. The aim of this study was to evaluate the clinical features and prognoses of children receiving IgM-enriched intravenous immunoglobulin to treat sepsis, septic shock, and multi-organ failure.

Method

We extracted data from the medical records of 254 children who received IgM-enriched intravenous immunoglobulin infusion (104 children for 3 days, 150 children for 5 days) in addition to standard treatment between 2010 and 2017.

Results

When the 5-day vs. 3-day IgM-enriched immunoglobulin treatments were compared, the mortality rate was shown to be lower in patients who received the longer duration of treatment (p < .001). Better outcomes were observed among children with septic shock (p < .01).

Conclusion

Our clinical work with 5-days IgM-enriched intravenous immunoglobulin may reveal a survival benefit of this treatment for children with septic shock.

A Randomized, Double-Blind, Placebo-Controlled Trial (TAURCAT Study) of Citrate Lock Solution for Prevention of Endoluminal Central Venous Catheter Infection in Neutropenic Hematological Patients

Infection of long-term central venous catheters (CVCs) remains a challenge in the clinical management of cancer patients. We aimed to determine whether a lock solution with taurolidine-citrate-heparin would be more effective than placebo for preventing nontunneled CVC infection in high-risk neutropenic hematologic patients. We performed a prospective, multicenter, randomized (1:1), double-blind, parallel, superiority, placebo-controlled trial involving 150 hematological patients with neutropenia carrying nontunneled CVCs who were assigned to receive CVC lock solution with taurolidine-citrate-heparin or heparin alone. The primary endpoint was bacterial colonization of the CVC hubs. Secondary endpoints were the incidence of catheter-related bloodstream infection (CRBSI), CVC removal, adverse events related to the lock solution, and the 30-day case fatality rate. CVC lock solution with taurolidine-citrate-heparin was associated with less colonization of the CVC hubs than that with placebo, with no statistically significant differences: 4.1%, versus 10.1% (relative risk [RR] = 0.41, 95% confidence interval [CI] = 0.11 to 1.52), with a cumulative incidence of 4.17 (95% CI = 0.87 to 11.70) and 10.14 (95% CI = 4.18 to 19.79), respectively. There were no significant differences regarding the secondary endpoints. Only three episodes of CRBSI occurred during the study period. No adverse events related to the administration of the lock solution occurred. In this trial involving high-risk patients carrying nontunneled CVCs, the use of taurolidine-citrate-heparin did not show a benefit over the use of placebo. Nevertheless, the safety of this prevention strategy and the trend toward less hub colonization in the taurolidine-citrate-heparin group raise the interest in assessing its efficacy in centers with higher rates of CRBSI. (This study has been registered in ISRCTN under identifier ISRCTN47102251.).

Impact of neutropenia on the clinical outcomes of Staphylococcus aureus bacteremia in patients with hematologic malignancies: a 10-year experience in a tertiary care hospital

Staphylococcus aureus bacteremia is one of the most serious bacterial infections and may lead to worse clinical outcomes in patients with prolonged severe neutropenia. However, clinical data on S. aureus bacteremia in neutropenic patients with hematologic malignancies are limited. We conducted two case-control studies using a 10-year prospective cohort of patients with S. aureus bacteremia. Neutropenic and non-neutropenic hematologic malignancy patients were compared on clinical characteristics and treatment outcomes. An additional matched case-control study using solid tumor patients was conducted. Risk factors for 12-week mortality were analyzed. Of 1643 patients with S. aureus bacteremia, 64 (3.9%) neutropenic and 108 (6.6%) non-neutropenic patients with hematologic malignancies were included in the study. There were no significant differences in the incidence of metastatic infection between the two groups (17.2% vs. 17.6%, p = 0.95), in contrast with a previous study that observed no metastatic infection in neutropenic patients. Twelve-week mortality in neutropenic patients with hematologic malignancies tended to be lower than in non-neutropenic patients with hematologic malignancies (15.6% vs. 26.9%, p = 0.09) and was significantly lower than in neutropenic patients with solid tumors (15.6% vs. 45.8%, p = 0.003). Independent risk factors for mortality in hematologic malignancy patients with S. aureus bacteremia were high Charlson comorbidity score, high APACHE II score, and skin and soft tissue infection. Neutropenia was not independently associated with mortality. Our findings suggest that neutropenia in hematologic malignancies may not affect the incidence of metastatic infection or 12-week mortality of S. aureus bacteremia.

Contribution of specific pathogens to bloodstream infection mortality in neutropenic patients with hematologic malignancies: Results from a multicentric surveillance cohort study

Bloodstream infection (BSI) remains a serious complication in patients with hematologic malignancies and neutropenia. The risk factors for mortality after BSI and the contributions of BSI pathogens to mortality remain incompletely understood. We evaluated first BSI among adult neutropenic patients undergoing high-dose chemotherapy for hematologic malignancies in the setting of (a) an early disease stage of autologous (auto-HSCT) or allogeneic (allo-HSCT) hematopoietic stem cell transplantation or (b) for acute leukemia. Risk factors for intensive care admission and all-cause mortality were analyzed by multivariable logistic regression 7 and 30 days after onset of the first BSI in the first neutropenic episode. Between 2002 and 2015, 9080 patients met the study inclusion criteria, and 1424 (16%) developed BSIs, most of them during the first week of neutropenia. Mortality during neutropenia within 7 days and 30 days after BSI onset was 2.5% and 5.1%, respectively, and differed considerably between BSI pathogens. Both 7-day and 30-day mortalities were highest for Pseudomonas aeruginosa BSI (16.7% and 26.7%, respectively) and lowest for BSI due to coagulase-negative Staphylococcus spp. (CoNS) and Streptococcus spp. BSI pathogens were independently associated with 7-day mortality included P aeruginosa, Klebsiella spp., Enterobacter spp., Serratia spp., and enterococci. Only gram-negative BSI and candidemia were associated with admission to intensive care within 7 days after BSI onset. BSI caused by P aeruginosa continues to carry a particularly poor prognosis in neutropenic patients. The unexpected association between enterococcal BSI and increased mortality needs further study.

Clinical effectiveness of carbapenems versus alternative antibiotics for treating ESBL-producing Enterobacteriaceae bacteraemia: a systematic review and meta-analysis

Objectives

The widespread administration of carbapenems to patients with ESBL-producing Enterobacteriaceae bacteraemia (ESBL-B) has accelerated the emergence of carbapenem-resistant Enterobacteriaceae. This study aimed to systematically review recently published data to evaluate the clinical effectiveness of carbapenems, compared with other antibiotics, in the treatment of ESBL-B.

Methods

We searched the Ovid-Medline, Ovid-Embase, Cochrane Library and five Korean local databases until January 2016. We selected studies that reported overall mortality in patients with ESBL-B who had been treated with carbapenems and alternatives. Overall mortality was assessed as the primary outcome and sepsis-related mortality and adverse events were analysed as secondary outcomes.

Results

Thirty-five publications fulfilled the inclusion criteria. Regarding empirical therapy, there were no significant differences between the groups that received carbapenems and those that received non-carbapenems in relation to overall mortality. Regarding definitive therapy, overall mortality was lower for patients administered carbapenems compared with those administered non-carbapenems [risk ratio (RR) 0.78, 95% CI 0.61-0.98], non-β-lactam/β-lactamase inhibitor combinations (non-BL/BLI) (RR 0.71, 95% CI 0.56-0.90) and cephalosporins (RR 0.56, 95% CI 0.42-0.74). There were no differences between the carbapenems and the other antibiotics, namely BL/BLIs, quinolones and aminoglycosides.

Conclusions

This meta-analysis showed that BL/BLIs may be promising alternative antibiotics for definitive therapy in patients with ESBL-B. However, the lack of robust data derived from randomized controlled trials limits the conclusions and inferences from the pooled data.

Predictors of multidrug-resistant Pseudomonas aeruginosa in neutropenic patients with bloodstream infection

OBJECTIVES

To assess risk factors for multidrug-resistant Pseudomonas aeruginosa (MDR-PA) infection in neutropenic patients.

METHODS

Single-centre retrospective analysis of consecutive bloodstream infection (BSI) episodes (2004-2017, Barcelona). Two multivariate regression models were used at BSI diagnosis and P. aeruginosa detection. Significant predictors were used to establish rules for stratifying patients according to MDR-PA BSI risk.

RESULTS

Of 661 Gram-negative BSI episodes, 190 (28.7%) were caused by P. aeruginosa (70 MDR-PA). Independent factors associated with MDR-PA among Gram-negative organisms were haematological malignancy (OR 3.30; 95% CI 1.15-9.50), pulmonary source of infection (OR 7.85; 95% CI 3.32-18.56), nosocomial-acquired BSI (OR 3.52; 95% CI 1.74-7.09), previous antipseudomonal cephalosporin (OR 13.66; 95% CI 6.64-28.10) and piperacillin/tazobactam (OR 2.42; 95% CI 1.04-5.63), and BSI occurring during ceftriaxone (OR 4.27; 95% CI 1.15-15.83). Once P. aeruginosa was identified as the BSI aetiological pathogen, nosocomial acquisition (OR 7.13; 95% CI 2.87-17.67), haematological malignancy (OR 3.44; 95% CI 1.07-10.98), previous antipseudomonal cephalosporin (OR 3.82; 95% CI 1.42-10.22) and quinolones (OR 3.97; 95% CI 1.37-11.48), corticosteroids (OR 2.92; 95% CI 1.15-7.40), and BSI occurring during quinolone (OR 4.88; 95% CI 1.58-15.05) and β-lactam other than ertapenem (OR 4.51; 95% CI 1.45-14.04) were independently associated with MDR-PA. Per regression coefficients, 1 point was assigned to each parameter, except for nosocomial-acquired BSI (3 points). In the second analysis, a score >3 points identified 60 (86.3%) out of 70 individuals with MDR-PA BSI and discarded 100 (84.2%) out of 120 with non-MDR-PA BSI.

CONCLUSIONS

A simple score based on demographic and clinical factors allows stratification of individuals with bacteraemia according to their risk of MDR-PA BSI, and may help facilitate the use of rapid MDR-detection tools and improve early antibiotic appropriateness.

The Gut Microbiota in Causation, Detection, and Treatment of Cancer

The gut microbiota has emerged as an important consideration in clinical oncology. The role of the microbiome in cancer extends beyond causation and cancer risk. It is now known that the microbiome not only acts at a local epithelial level in the gut but also modifies immune responses within intestinal and extraintestinal tumors. Microbial signaling influences the clinical course of cancer including the efficacy, bioavailability, and toxicity of chemotherapeutic and immunotherapy agents. This has focused research on microbiota profiling in different cancer states with an aim of developing prognostic biomarkers of risk. The potential value of microbiome manipulation with live biotherapeutics or microbial transplantation has also become a realistic consideration. Maintenance of microbial diversity in patients with cancer is a variable challenge given the modifying influences of the tumor itself, chemotherapy, nutritional status, and sporadic antimicrobial therapy. Here, we address current evidence for the role of the microbiome in cancer therapy.

Impact of antibiotic resistance on outcomes of neutropenic cancer patients with Pseudomonas aeruginosa bacteraemia (IRONIC study): study protocol of a retrospective multicentre international study

INTRODUCTION

Pseudomonas aeruginosa (PA) has historically been one of the major causes of severe sepsis and death among neutropenic cancer patients. There has been a recent increase of multidrug-resistant PA (MDRPA) isolates that may determine a worse prognosis, particularly in immunosuppressed patients. The aim of this study is to establish the impact of antibiotic resistance on the outcome of neutropenic onco-haematological patients with PA bacteraemia, and to identify the risk factors for MDRPA bacteraemia and mortality.

METHODS AND ANALYSIS

This is a retrospective, observational, multicentre, international study. All episodes of PA bacteraemia occurring in neutropenic onco-haematological patients followed up at the participating centres from 1 January 2006 to 31 May 2018 will be retrospectively reviewed. The primary end point will be overall case-fatality rate within 30 days of onset of PA bacteraemia. The secondary end points will be to describe the following: the incidence and risk factors for multidrug-resistant and extremely drug-resistant PA bacteraemia (by comparing the episodes due to susceptible PA with those produced by MDRPA), the efficacy of ceftolozane/tazobactam, the rates of persistent bacteraemia and bacteraemia relapse and the risk factors for very early (48 hours), early (7 days) and overall (30 days) case-fatality rates.

ETHICS AND DISSEMINATION

The Clinical Research Ethics Committee of Bellvitge University Hospital approved the protocol of the study at the primary site. To protect personal privacy, identifying information of each patient in the electronic database will be encrypted. The processing of the patients' personal data collected in the study will comply with the Spanish Data Protection Act of 1998 and with the European Directive on the privacy of data. All data collected, stored and processed will be anonymised. Results will be reported at conferences and in peer-reviewed publications.

Multidrug-resistant bacterial infections in patients with decompensated cirrhosis and with acute-on-chronic liver failure in Europe

BACKGROUND & AIMS

Antibiotic resistance has been increasingly reported in patients with decompensated cirrhosis in single-center studies. Prospective investigations reporting broad epidemiological data are scarce. We aimed to analyze epidemiological changes in bacterial infections in patients with decompensated cirrhosis.

METHODS

This was a prospective evaluation of 2 series of patients hospitalized with decompensated cirrhosis. The Canonic series included 1,146 patients from Northern, Southern and Western Europe in 2011. Data on epidemiology, clinical characteristics of bacterial infections, microbiology and empirical antibiotic schedules were assessed. A second series of 883 patients from Eastern, Southern and Western Europe was investigated between 2017-2018.

RESULTS

A total of 455 patients developed 520 infections (39.7%) in the first series, with spontaneous bacterial peritonitis, urinary tract infections and pneumonia the most frequent infections. Nosocomial episodes predominated in this series. Nearly half of the infections were culture-positive, of which 29.2% were caused by multidrug-resistant organisms (MDROs). MDR strains were more frequently isolated in Northern and Western Europe. Extended-spectrum beta-lactamase-producing Enterobacteriaceae were the most frequent MDROs isolated in this series, although prevalence and type differed markedly among countries and centers. Antibiotic resistance was associated with poor prognosis and failure of antibiotic strategies, based on third-generation cephalosporins or quinolones. Nosocomial infection (odds ratio [OR] 2.74; p < 0.001), intensive care unit admission (OR 2.09; p = 0.02), and recent hospitalization (OR 1.93; p = 0.04) were identified as independent predictors of MDR infection. The prevalence of MDROs in the second series (392 infections/284 patients) was 23%; 38% in culture-positive infections. A mild increase in the rate of carbapenem-resistant Enterobacteriaceae was observed in this series.

CONCLUSIONS

MDR bacterial infections constitute a prevalent, growing and complex healthcare problem in patients with decompensated cirrhosis and acute-on-chronic liver failure across Europe, negatively impacting on prognosis. Strategies aimed at preventing the spread of antibiotic resistance in cirrhosis should be urgently evaluated.

LAY SUMMARY

Infections caused by bacteria resistant to the main antibiotic families are prevalent in patients with cirrhosis. This study demonstrates that this healthcare problem is increasing and extends through all European regions. Infections caused by these difficult to treat bacteria resolve less frequently and often cause the death of the patient. The type of resistant bacteria varies markedly among different hospitals.

Procalcitonin as a marker of Gram-negative bloodstream infections in hematological patients with febrile neutropenia

The aim of this study was to explore the predictive value of procalcitonin (PCT) in Gram-negative bloodstream infections (BSIs) in hematological patients with febrile neutropenia. A total of 1466 samples (396 blood culture (BC)-positive, 1052 BC-negative, and 18 contaminated specimens) were included, comprising 268 Gram-negative, 88 Gram-positive, 19 fungal, and 21 polymicrobial BSIs. Median PCT value (0.72 ng/mL; IQR: 0.23-3.87) was significantly higher in Gram-negative than Gram-positive (0.34 ng/mL; IQR: 0.14-2.23; p < .01), or fungal (0.27 ng/mL; IQR: 0.13-0.40; p < .01) BSIs. In mono-microbial BSIs, the best PCT cutoff distinguishing Gram-negative BSIs from all other fever causes was 0.56 ng/ml, with a specificity of 76.8%. PCT levels were significantly higher in BSIs from multidrug-resistant (MDR) Gram-negative strains than from non-MDR (p < .01). This study confirms that elevated PCT may predict Gram-negative BSIs in hematological patients with febrile neutropenia, and demonstrates higher PCT levels in MDR Gram-negative BSIs in these patients.

Colonization with multidrug resistant organisms determines the clinical course of patients with acute myeloid leukemia undergoing intensive induction chemotherapy

Introduction

The global spread of multidrug-resistant organisms (MDRO) complicates treatment and isolation measures in hospitals and has shown to increase mortality. Patients with disease- or therapy-related immunodeficiency are especially at risk for fatal infections caused by MDRO. The impact of MDRO colonization on the clinical course of AML patients undergoing intensive induction chemotherapy—a potentially curative but highly toxic treatment option—has not been systematically studied.

Materials & methods

312 AML patients undergoing intensive induction chemotherapy between 2007 and 2015 were examined for MDRO colonization. Patients with evidence for MDRO before or during the hospital stay of induction chemotherapy were defined as colonized, patients who never had a positive swab for MDRO were defined as noncolonized.

Results

Of 312 AML patients 90 were colonized and 130 were noncolonized. Colonized patients suffered from significantly more days with fever, spent more days on the intensive care unit and had a higher median C-reactive protein value during the hospital stay. These findings did not result in a prolonged length of hospital stay or an increased mortality rate for colonized patients. However, in a subgroup analysis, patients colonized with carbapenem-resistant enterobacteriaceae (CRE) had a significantly reduced 60- and 90-day, as well as 1- and 2-year survival rates when compared to noncolonized patients.

Conclusion

Our analysis highlights the importance of intensive MDRO screening especially in patients with febrile neutropenia since persisting fever can be a sign of MDRO-colonization. CRE-colonized patients require special surveillance, since they seem to be at risk for death.

Early discontinuation of antibiotics for febrile neutropenia versus continuation until neutropenia resolution in people with cancer

BACKGROUND

People with cancer with febrile neutropenia are at risk of severe infections and mortality and are thus treated empirically with broad-spectrum antibiotic therapy. However, the recommended duration of antibiotic therapy differs across guidelines.

OBJECTIVES

To assess the safety of protocol-guided discontinuation of antibiotics regardless of neutrophil count, compared to continuation of antibiotics until neutropenia resolution in people with cancer with fever and neutropenia, in terms of mortality and morbidity. To assess the emergence of resistant bacteria in people with cancer treated with short courses of antibiotic therapy compared with people with cancer treated until resolution of neutropenia.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 10) in the Cochrane Library, MEDLINE, Embase, and LILACS up to 1 October 2018. We searched the metaRegister of Controlled Trials and the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov for ongoing and unpublished trials. We reviewed the references of all identified studies for additional trials and handsearched conference proceedings of international infectious diseases and oncology and haematology conferences.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared a short antibiotic therapy course in which discontinuation of antibiotics was guided by protocols regardless of the neutrophil count to a long course in which antibiotics were continued until neutropenia resolution in people with cancer with febrile neutropenia. The primary outcome was 30-day or end of follow-up all-cause mortality.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed all studies for eligibility, extracted data, and assessed risk of bias for all included trials. We calculated risk ratios (RRs) with 95% confidence intervals (CIs) whenever possible. For dichotomous outcomes with zero events in both arms of the trials, we conducted meta-analysis of risk differences (RDs) as well. For continuous outcomes, we extracted means with standard deviations (SD) from the studies and computed mean difference (MD) and 95% CI. If no substantial clinical heterogeneity was found, trials were pooled using the Mantel-Haenszel fixed-effect model.

MAIN RESULTS

We included eight RCTs comprising a total of 662 distinct febrile neutropenia episodes. The studies included adults and children, and had variable design and criteria for discontinuation of antibiotics in both study arms. All included studies but two were performed before the year 2000. All studies included people with cancer with fever of unknown origin and excluded people with microbiological documented infections.We found no significant difference between the short-antibiotic therapy arm and the long-antibiotic therapy arm for all-cause mortality (RR 1.38, 95% CI 0.73 to 2.62; RD 0.02, 95% CI -0.02 to 0.05; low-certainty evidence). We downgraded the certainty of the evidence to low due to imprecision and high risk of selection bias. The number of fever days was significantly lower for people in the short-antibiotic treatment arm compared to the long-antibiotic treatment arm (mean difference -0.64, 95% CI -0.96 to -0.32; I² = 30%). In all studies, total antibiotic days were fewer in the intervention arm by three to seven days compared to the long antibiotic therapy. We found no significant differences in the rates of clinical failure (RR 1.23, 95% CI 0.85 to 1.77; very low-certainty evidence). We downgraded the certainty of the evidence for clinical failure due to variable and inconsistent definitions of clinical failure across studies, possible selection bias, and wide confidence intervals. There was no significant difference in the incidence of bacteraemia occurring after randomisation (RR 1.56, 95% CI 0.91 to 2.66; very low-certainty evidence), while the incidence of any documented infections was significantly higher in the short-antibiotic therapy arm (RR 1.67, 95% CI 1.08 to 2.57). There was no significant difference in the incidence of invasive fungal infections (RR 0.86, 95% CI 0.32 to 2.31) and development of antibiotic resistance (RR 1.49, 95% CI 0.62 to 3.61). The data on hospital stay were too sparse to permit any meaningful conclusions.

AUTHORS' CONCLUSIONS

We could make no strong conclusions on the safety of antibiotic discontinuation before neutropenia resolution among people with cancer with febrile neutropenia based on the existing evidence and its low certainty. Results of microbiological outcomes favouring long antibiotic therapy may be misleading due to lower culture positivity rates under antibiotic therapy and not true differences in infection rates. Well-designed, adequately powered RCTs are required that address this issue in the era of rising antibiotic resistance.

An in-depth analysis of nosocomial bloodstream infections due to Gram-negative bacilli: clinical features, microbiological characteristics and predictors of mortality in a 1 year, prospective study in a large tertiary care Italian hospital

BACKGROUND

Bloodstream infections (BSI) due to Gram negative bacilli (GNB) represent a major concern among nosocomial infections, since they are noticeably associated with a high mortality rates, increase of healthcare costs and prolongation of hospital stay.

METHODS

Over a 12-month period (2014-2015) all the adult patients admitted to a university-based Italian hospital were monitored for development of BSIs due to GNB. Multiple logistics regression models were performed to assess the impact of patients' risk factors on the in-hospital and 14-day mortality.

RESULTS

During the study period 208 patients were diagnosed with at least a BSI due to a Gram negative species for an incidence rate of 12.8 cases/1,000 admissions (95%CI: 11.2-14.7). Multivariate analyses showed that multiple organ dysfunctions along with immune deficit and inadequate therapy in the first 48hrs were associated with a higher risk of death.

CONCLUSIONS

A thorough evaluation of both immune status and organ dysfunction at the onset of septic events, along with adequate antimicrobial therapy appear to be the most reliable factors in predicting the outcome in these infections. SOFA score can be efficaciously substituted to the single organ dysfunctions analysis in predicting mortality after these events.

Genomes of Escherichia coli bacteraemia isolates originating from urinary tract foci contain more virulence-associated genes than those from non-urinary foci and neutropaenic hosts

Objectives

Escherichia coli is the leading cause of bacteraemia. In an era of emerging multi-drug-resistant strains, development of effective preventative strategies will be informed by knowledge of strain diversity associated with specific infective syndromes/patient groups. We hypothesised that the number of virulence factor (VF) genes amongst bacteraemia isolates from neutropaenic patients would be lower than isolates from immunocompetent patients.

Methods

Immunocompetent and neutropaenic adults with E. coli bacteraemia were recruited prospectively and the source of bacteraemia determined. VF gene profiles were established in silico following whole genome sequencing.

Results

Isolates from individual patients were monoclonal. Strains from immunocompetent patients with urinary tract infective foci (UTIF) harboured more VF genes (median number of VF genes 16, range 8–24) than isolates from both immunocompetent patients with non-UTIF (10, 2–22, p = 0.0058) and neutropaenic patients with unknown focus of infection (NPUFI) (8, 3–13, p < 0.0001). Number of VF genes (OR 1.21, 95% CIs 1.01–1.46, p = 0.039) and urinary catheter/recurrent urinary tract infection (OR 12.82, 95% CIs 1.24–132.65, p = 0.032) were independent predictors of bacteraemia secondary to UTIF vs. non-UTIF in immunocompetent patients. papA, papC, papE/F, papG, agn43, tia, iut, fyuA, kpsM and sat were significantly more prevalent amongst UTIF- vs non-UTIF-originating isolates amongst immunocompetent patients, while papC, papE/F, papG, agn43, tia, fyuA, hlyA, usp and clb were significantly more prevalent amongst UTIF- vs NPUFI-associated isolates.

Conclusions

Bacteraemia-associated E. coli strains originating from UTIF have distinct VF gene profiles from strains associated with non-UTIF- and NPUFI. This diversity must be addressed in the design of future vaccines to ensure adequate coverage of strains responsible for site-specific disease.

Microbial spectrum and drug-resistance profile of isolates causing bloodstream infections in febrile cancer patients at a referral hospital in Addis Ababa, Ethiopia

Background

The spectrum of pathogens causing bloodstream infections (BSIs) in cancer patients has shown significant fluctuations in different geographical areas and time. We studied the microbial spectrum and drug-resistance profile of pathogens causing BSIs in febrile cancer patients at a referral hospital in Ethiopia.

Methods

This cross-sectional study was conducted between December 2011 and June 2012 at Tikur Anbessa Hospital in Addis Ababa. Blood cultures from febrile cancer patients (n=107) were performed. Bacterial and fungal pathogens were identified and antimicrobial susceptibility testing done for the bacterial isolates using the Kirby-Bauer disk diffusion method.

Results

A total of 82 pathogens were isolated from 112 blood culture tests of the 76 patients: 71 (86.6%) of the isolates were bacteria and 11 (13.4%) were fungi. The majority (60.5% [43 of 71]) of the isolates were Gram-positive bacteria, where Staphylococcus aureus was predominant (72% [31 of 43]), and 68% of S. aureus isolates were resistant to ceftriaxone and oxacillin. Gram-negative bacteria accounted for 39.5% (28 of 71) of the isolates. Stenotrophomonas maltophilia (17.9% [five of 28]) was the most frequent Gram-negative isolate. In Gram-negative bacteria, the highest rates of resistance were observed in amoxicillin-clavulanic acid (80% [12 of 15]), followed by ceftriaxone (73.3%) and trimethoprim-sulfamethoxazole (73.3%). Multidrug resistance (resistance to three or more types of antibiotics, in this case to ceftriaxone, tetracycline, and trimethoprim-sulfamethoxazole) was observed in 26.3% (13 of 43) of Gram-positive and 40% (six of 16) of Gram-negative bacteria. Neutropenia was an independent risk factor for BSIs (P=0.02).

Conclusion

Gram-positive bacteria were the predominant etiologic agents of BSIs in Ethiopian patients with cancer. Both Gram-positive and Gram-negative bacteria showed an increasing level of resistance for most of the antibiotics used for empiric therapy. Routine bacterial surveillance and study of their resistance patterns must be an essential component of cancer-related infection control and care in our setting.

Update on infection control practices in cancer hospitals

Therapies in oncology have evolved rapidly over the last years. At the same pace, supportive care for patients receiving cancer therapy has also evolved, allowing patients to safely receive the newest advances in treatment in both an inpatient and outpatient basis. The recognition of the role of infection control and prevention (ICP) in the outcomes of patients living with cancer has been such that it is now a requirement for hospitals and involves multidisciplinary groups. Some unique aspects of ICP for patients with cancer that have gained momentum over the past few decades include catheter-related infections, multidrug-resistant organisms, community-acquired viral infections, and the impact of the health care environment on the horizontal transmission of organisms. Furthermore, as the potential for infections to cross international borders has increased, alertness for outbreaks or new infections that occur outside the area have become constant. As the future approaches, ICP in immunocompromised hosts will continue to integrate emerging disciplines, such as antibiotic stewardship and the microbiome, and new techniques for environmental cleaning and for controlling the spread of infections, such as whole-genome sequencing. CA Cancer J Clin 2018;000:000-000. © 2018 American Cancer Society.

Current time-to-positivity of blood cultures in febrile neutropenia: a tool to be used in stewardship de-escalation strategies

OBJECTIVES

We aimed to describe the current time-to-positivity (TTP) of blood cultures in individuals with onco-haematological diseases with febrile neutropenia. We assessed the probability of having a multidrug-resistant Gram-negative bacilli (MDR-GNB) bloodstream infection (BSI) 24 h after cultures were taken, to use this information for antibiotic de-escalation strategies.

METHODS

BSI episodes were prospectively collected (2003-2017). When a patient experienced more than one BSI, only one episode was randomly chosen. Time elapsed from the beginning of incubation to a positive reading was observed; TTP was recorded when the first bottle had a positive result.

RESULTS

Of the 850 patient-unique episodes, 323 (38%) occurred in acute leukaemia, 185 (21.8%) in non-Hodgkin's lymphoma and 144 (16.9%) in solid neoplasms. Coagulase-negative staphylococci (225; 26.5%), Escherichia coli (207; 26.1%), Pseudomonas aeruginosa (136; 16%), Enterococcus spp. (81; 9.5%) and Klebsiella pneumoniae (67; 7.9%), were the most frequent microorganisms isolated. MDR-GNB were documented in 126 (14.8%) episodes. Median TTP was 12 h (interquartile range 9-16.5 h). Within the first 24 h, 92.1% of blood cultures were positive (783/850). No MDR-GNB was positive over 24 h. Of the 67 (7.9%) episodes with a TTP ≥24 h, 25 (37.3%) occurred in patients who were already receiving active antibiotics against the isolated pathogen. Most common isolations with TTP ≥24 h were coagulase-negative staphylococci, candidaemia and a group of anaerobic GNB.

CONCLUSIONS

Currently, the vast majority of BSI in individuals with onco-haematological diseases with febrile neutropenia have a TTP <24 h, including all episodes caused by MDR-GNB. Our results support reassessing empiric antibiotic treatment in neutropenic patients at 24 h, to apply antibiotic stewardship de-escalation strategies.

Risk for subsequent infection and mortality after hospitalization among patients with multidrug-resistant gram-negative bacteria colonization or infection

Background

Risks for subsequent multidrug-resistant gram-negative bacteria (MDRGNB) infection and long-term outcome after hospitalization among patients with MDRGNB colonization remain unknown.

Methods

This observational study enrolled 817 patients who were hospitalized in the study hospital in 2009. We defined MDRGNB as a GNB resistant to at least three different antimicrobial classes. Patients were classified into MDRGNB culture-positive (MDRGNB-CP; 125 patients) and culture-negative (MDRGNB-CN; 692 patients) groups based on the presence or absence of any MDRGNB identified from either active surveillance or clinical cultures during index hospitalization. Subsequent MDRGNB infection and mortality within 12 months after index hospitalization were recorded. We determined the frequency and risk factors for subsequent MDRGNB infection and mortality associated with previous MDRGNB culture status.

Results

In total, 129 patients had at least one subsequent MDRGNB infection (MDRGNB-CP, 48.0%; MDRGNB-CN, 10.0%), and 148 patients died (MDRGNB-CP, 31.2%; MDRGNB-CN, 15.9%) during the follow-up period. MDR Escherichia coli and Acinetobacter baumannii were the predominant colonization microorganisms; patients with Proteus mirabilis and Pseudomonas aeruginosa had the highest hazard risk for developing subsequent infection. After controlling for other confounders, MDRGNB-CP during hospitalization independently predicted subsequent MDRGNB infection (hazard ratio [HR], 5.35; 95% confidence interval [CI], 3.72–7.71), all-cause mortality (HR, 2.42; 95% CI, 1.67–3.50), and subsequent MDRGNB infection-associated mortality (HR, 4.88; 95% CI, 2.79–8.52) after hospitalization.

Conclusions

Harboring MDRGNB significantly increases patients’ risk for subsequent MDRGNB infection and mortality after hospitalization, justifying the urgent need for developing effective strategies to prevent and eradicate MDRGNB colonization.

De-escalation and discontinuation strategies in high-risk neutropenic patients: an interrupted time series analyses of antimicrobial consumption and impact on outcome

Febrile neutropenia (FN) is the main reason for antibiotic prescription in hematology wards where, on the other hand, antibiotic stewardship (AS) is poorly explored. The objectives of the present study were to evaluate (1) the impact of an AS intervention on antibiotic consumption and (2) the applicability and acceptance rate of the intervention and its clinical impact. A persuasive AS intervention based on European Conference on Infection in Leukaemia (ECIL) guidelines for FN was implemented in a high-risk hematology ward in a tertiary referral public university hospital. This included the creation and diffusion of flow charts on de-escalation and discontinuation of antibiotics for FN, and the introduction in the team of a doctor dedicated to the implementation of flow charts and to antibiotic prescription revision. All consecutive patients receiving antibiotics during hospitalization were included. A segmented linear regression model was performed for the evaluation of antibiotic consumption, taking into account 1-year pre-intervention period and 6-month intervention period. Overall, 137 consecutive antibiotic prescriptions were re-evaluated, 100 prescriptions were for FN. A significant reduction of the level of carbapenem consumption was observed during the intervention period (level change (estimate coefficient ± standard error) = - 135.28 ± 59.49; p = 0.04). Applicability and acceptability of flow charts were high. No differences in terms of intensive care unit transfers, bacteremia incidence, and mortality were found. A persuasive AS intervention in hematology significantly reduced carbapenem consumption without affecting outcome and was well accepted. This should encourage further applications of ECIL guidelines for FN.

Risk factors for mortality in patients with acute leukemia and bloodstream infections in the era of multiresistance

Objectives

We assess the epidemiology and risk factors for mortality of bloodstream infection (BSI) in patients with acute leukemia (AL).

Methods

Prospectively collected data of a cohort study from July 2004 to February 2016. Multivariate analyses were performed.

Results

589 episodes of BSI were documented in 357 AL patients, 55% caused by gram-positive bacteria (coagulase-negative staphylococci 35.7%, Enterococcus spp 10.8%) and 43.5% by gram-negative bacteria (E. coli 21%, PA 12%). We identified 110 (18.7%) multidrug-resistant (MDR) microorganisms, especially MDR-Pseudomonas aeruginosa (7%) and extended-spectrum beta-lactamase producing Enterobacteriaceae (7%). The 30-day mortality was 14.8%. Age (OR 3.1; 95% CI 1.7–5.7); chronic lung disease (4.8; 1.1–21.8); fatal prognosis according to McCabe index (13.9; 6.4–30.3); shock (3.8; 1.9–7.7); pulmonary infection (3.6; 1.3–9.9); and MDR-PA infections with inappropriate treatment (12.8; 4.1–40.5) were related to mortality. MDR-PA BSI was associated to prior antipseudomonal cephalosporin use (9.31; 4.38–19.79); current use of betalactams (2.01; 1.01–4.3); shock (2.63; 1.03–6.7) and pulmonary source of infection (9.6; 3.4–27.21).

Conclusions

MDR organisms were commonly isolated in BSI in AL. Inappropriate empiric antibiotic treatment for MDR-PA is the primary factor related to mortality that can be changed. New treatment strategies to improve the coverage of MDR-PA BSI should be considered in those patients with risk factors for this infection.

Bloodstream infection in patients with head and neck cancer: a major challenge in the cetuximab era

PURPOSE

To assess the impact of bloodstream infection (BSI) in patients with head and neck cancer (HNC) in the cetuximab era.

METHODS

We prospectively analysed the epidemiology, microbiology and outcomes of 51 BSI episodes occurring in 48 patients with HNC (2006-2017). We performed a retrospective matched-cohort study (1:2) to determine the risk factors for BSI. Finally, we compared patients who died with those who survived to identify risk factors for mortality.

RESULTS

The most frequent HNC localization was the oropharynx (43%), and pneumonia was the most frequent source (25%). Gram-positive BSI occurred in 55% cases, mainly due to Streptococcus pneumoniae (21%), and among Gram-negatives, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae were the most frequent. Hypoalbuminemia (OR 8.4; 95% CI, 3.5-19.9), previous chemotherapy (OR, 3.2; 95% CI, 1.3-7.4) and cetuximab therapy (OR, 2.8; 95% CI, 1.6-6.7) were significant risk factors for BSI. Patients with BSI had a higher overall case-fatality rate than patients without BSI (OR, 4.4; 95% CI, 1.7-11.8). Hypoalbuminemia was an independent risk factor for the early (7 day) and overall (30 day) case-fatalities, with ORs of 0.8 (95% CI, 0.6-0.9) and 0.8 (95% CI, 0.7-0.97), respectively. The presence of comorbidities (OR, 7; 95% CI, 1.4-34) was also an independent risk factor for overall case-fatality.

CONCLUSIONS

BSI causes high mortality in patients with HNC and is most often secondary to pneumonia. It occurs mainly among patients with hypoalbuminemia who receive treatment with cetuximab or chemotherapy. The development of BSI in patients with HNC impairs their outcome, especially in the presence of hypoalbuminemia and comorbidities.

Administration of taurolidine-citrate lock solution for prevention of central venous catheter infection in adult neutropenic haematological patients: a randomised, double-blinded, placebo-controlled trial (TAURCAT)

Background

Catheter-related bloodstream infection (CRBSI) is one of the most frequent complications in patients with cancer who have central venous catheters (CVCs) implanted and is associated with substantial morbidity and mortality. Taurolidine is a non-antibiotic agent with broad-spectrum antimicrobial activity, which has been used as a lock solution to prevent CRBSI in some settings. However, little is known about its usefulness in high-risk adult neutropenic patients with cancer. This prospective randomised clinical trial aims to test the hypothesis that taurolidine-citrate lock solution is more effective than placebo for preventing catheter infection in neutropenic haematological patients.

Methods

This study is a prospective, multicentre, randomised, double-blinded, parallel, superiority, placebo-controlled trial. Patients with haematological cancer who are expected to develop prolonged neutropenia (> 7 days) and who have a non-tunnelled CVC implanted will be randomised to receive prophylactic taurolidine-citrate-heparin solution using a lock technique (study group) or heparin alone (placebo group). The primary endpoint will be bacterial colonisation of the CVC hubs. The secondary endpoints will be the incidence of CRBSI, CVC removal, adverse events, and 30-day case-fatality rate.

Discussion

The lock technique is a preventive strategy that inhibits bacterial colonisation in the catheter hubs, which is the initial step of endoluminal catheter colonisation and the development of infection. Taurolidine is a nontoxic agent that does not develop antibiotic resistance because it acts as an antiseptic rather than an antibiotic. Taurolidine has shown controversial results in the few trials conducted in cancer patients. These studies have important limitations due to the lack of data on adult and/or high-risk neutropenic patients, the type of catheters studied (tunnelled or ports), and the lack of information regarding the intervention (e.g. dwelling of the solution, time, and periodicity of the lock technique). If our hypothesis is proven, the study could provide important solid evidence on the potential usefulness of this preventive procedure in a population at high risk of CRBSI, in whom this complication may significantly impair patient outcome.

Trial registration

ISRCTN, ISRCTN47102251. Registered on 9 September 2015.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2647-y) contains supplementary material, which is available to authorized users.

Changes in bacterial epidemiology and antibiotic resistance among veterans with spinal cord injury/disorder over the past 9 years

OBJECTIVE

Patients with spinal cord injury and disorder (SCI/D) have an increased risk of infection with multidrug-resistant (MDR) bacteria. We described bacterial epidemiology and resistance in patients with SCI/D at Veterans Affairs Medical Centers (VAMCs) for the past 9 years.

DESIGN

Retrospective cohort.

SETTING

One hundred thirty VAMCs.

PARTICIPANTS

Veterans with SCI/D and bacterial cultures with antibiotic susceptibility testing performed between 1/1/2005-12/31/2013. Single cultures with contaminants and duplicate isolates within 30 days of initial isolates were excluded.

INTERVENTIONS

None.

OUTCOMES

Trends in microbial epidemiology and antibiotic resistance.

RESULTS

Included were 216,504 isolates from 19,421 patients. Urine was the most common source and Gram-negative bacteria (GNB) were isolated most often, with 36.1% of GNB being MDR. Logistic regression models clustered by patient and adjusted for location at an SCI/D center and geographic region showed increased odds over time of vancomycin resistance in Enterococcus [adjusted odds ratio (aOR) 1.67, 95% confidence interval (CI) 1.30-2.15], while methicillin resistance in Staphylococcus aureus remained unchanged (aOR 0.90, 95% CI 0.74-1.09). There were also increased odds of fluoroquinolone resistance (aOR 1.39, 95% CI 1.31-1.47) and multidrug resistance (aOR 1.46, 95% CI 1.38-1.55) in GNB, with variability in the odds of MDR bacteria by geographic region.

CONCLUSIONS

GNB are isolated frequently in Veterans with SCI/D and have demonstrated increasing resistance over the past 9 years. Priority should be given to controlling the spread of resistant bacteria in this population. Knowledge of local and regional epidemiologic trends in antibiotic resistance in patients with SCI/D may improve appropriate antibiotic prescribing.

A fresh look at polymicrobial bloodstream infection in cancer patients

Objectives

To assess the current incidence, clinical features, risk factors, aetiology, antimicrobial resistance and outcomes of polymicrobial bloodstream infection (PBSI) in patients with cancer.

Methods

All prospectively collected episodes of PBSI in hospitalised patients were compared with episodes of monomicrobial bloodstream infection (MBSI) between 2006 and 2015.

Results

We identified 194 (10.2%) episodes of PBSI and 1702 MBSI (89.8%). The presence of cholangitis, biliary stenting, neutropenia, corticosteroids, neutropenic enterocolitis and other abdominal infections were identified as risk factors for PBSI. Overall, Gram-negative organisms were the most frequent aetiology, but Enterococcus spp. were especially frequent causes of Gram-positive PBSI (30.8%). Multidrug-resistant (MDR) organisms were more commonly found in PBSI than in MBSI (20.6% vs 12.9%; p = 0.003). Compared to patients with MBSI, those with PBSI presented with higher early (15% vs 1.4%; p = 0.04) and overall (32% vs 20.9%; p<0.001) case-fatality rates. Risk factors for overall case-fatality were a high-risk MASCC (Multinational Association of Supportive Care in Cancer) index score, corticosteroid use, persistent bacteraemia and septic shock.

Conclusions

PBSI is a frequent complication in patients with cancer and is responsible for high mortality rates. Physicians should identify patients at risk for PBSI and provide empiric antibiotic therapy that covers the most frequent pathogens involved in these infections, including MDR strains.

Prevalence and risk factors of Gram-negative bacilli causing blood stream infection in patients with malignancy

Objectives:

To evaluate the epidemiology, risk factors, and antibiotic resistance of Gram negative bacteria (GNB) in patients with hematologic or solid organ malignancies.

Methods:

This is a retrospective study of 61 episodes of GNB bacteremia occurring in 56 patients with malignancy admitted to the Oncology Units in King Khalid University Hospital, Riyadh. Kingdom of Saudi Arabia during the period from January 2013 to October 2015. Data were retrieved from the computerized database of the microbiology laboratory and the patient’s medical records.

Results:

Hematological malignancies accounted for 30 (54%) and solid tumors accounted for 26 (46%). The most common hematological malignancies were leukemia 23 (77%), followed by lymphoma 6 (20%). Among solid tumors, colorectal cancer 9 (34.6) and breast cancer 6 (23%) were the most common. The most predominant pathogen was Escherichia coli (E. coli) (29.5%) followed by Acinetobacter baumannii (A. baumannii) (18%). The extended-spectrum beta-lactamases producers rate of E. coli and Klebsiella pneumonia was (34.6%). Imipenem resistance among Pseudomonas aeruginosa/A. baumannii was high (52.4%). The multi-resistant organisms rate was (43.5%). Risk factors associated with the bacteremia were ICU admission (32.1%), post-surgery (23.2%), and placement of central line (21.4%). The overall 30-day mortality rate of the studied population was high (32.1%).

Conclusion:

In light of the high resistant rate among the GNB isolated from malignancy patients from our institution, careful selection of antimicrobial treatment based on antimicrobial susceptibility testing is recommended.

Epidemiology and management of healthcare-associated bloodstream infections in non-neutropenic immunosuppressed patients: a review of the literature

Advancements in medicine have led to a considerable increase in the proportion of patients living with severe chronic diseases, malignancies, and HIV infections. Most of these conditions are associated with acquired immune-deficient states and treatment-related immunosuppression. Although infections as a result of neutropenia have long been recognized and strategies for management were developed, non-neutropenic immunosuppression has been overlooked. Recently, community-acquired infections in patients with frequent, significant exposure to healthcare settings and procedures have been classified as 'healthcare-associated infections' since they are more similar to hospital-acquired infections. Most of the non-neutropenic immunosuppressed patients have frequent contact with the healthcare system due to their chronic and severe diseases. In this review, we focus on the healthcare-associated bloodstream infections in the most common non-neutropenic immunosuppressive states and provide an update of the recent evidence for the management of these infections.

Risk factors for cefepime nonsusceptible Gram-negative infections in allogeneic hematopoietic cell transplant recipients

Purpose

Allogeneic hematopoietic cell transplant recipients undergo myelosuppressive chemotherapy to allow engraftment of stem cells and are at particularly high risk for bacterial infections and adverse outcomes. Patients undergoing hematopoietic cell transplant are at increased risk for healthcare-associated infections, including infections with multidrug-resistant pathogens. Cefepime is a commonly prescribed antibiotic for empiric therapy in hematopoietic cell transplant patients, but there is minimal data describing cefepime resistance rates, risk factors for resistance, and clinical outcomes associated with cefepime-resistant infections.

Methods

Adult (≥18 years old) allogeneic hematopoietic cell transplant recipients with a culture positive for a gram-negative rod between January 2010 and January 2016 were spilt into two groups: cefepime susceptible and cefepime nonsusceptible . The primary objective of this study was to identify risk factors for cefepime nonsusceptible through multivariable logistic regression.

Results

A total of 107 patients were included (27 cefepime nonsusceptible, 80 cefepime-susceptible), yielding a 25.2% nonsusceptibility rate. Multivariable analysis yielded age >60 years old, Klebsiella spp. infection, Acinetobacter spp. infection, healthcare exposures within 90 days, acute gastrointestinal graft-vs-host-disease, and chronic graft-vs-host-disease at multiple locations as significant risk factors for cefepime nonsusceptible. The receiver operating characteristic area under the curve of the model was 0.851. Thirty-day all-cause mortality (29.6% versus 16.3%, p = 0.13) and length of hospitalization (19 versus 12.5 days, p = 0.0650) were numerically higher in the cefepime nonsusceptible group.

Conclusions

Hematopoietic cell transplant patients with acute gastrointestinal graft versus host disease, extensive chronic graft-vs-host-disease, advanced age, previous healthcare exposures, or infections with Klebsiella and Acinetobacter are at increased risk for cefepime nonsusceptible. Patients infected with cefepime nonsusceptible pathogens may have higher rates of mortality and length of hospitalization.

Risk factors and outcomes for multidrug-resistant Gram-negative bacilli bacteremia

Background

The incidence of multidrug-resistant (MDR) organisms is increasing along with mortality. Identifying risk factors for the development of MDR Gram-negative bacilli (GNB) bacteremia could greatly impact patient care and management.

Methods

Data from the electronic health record of patients with GNB over 13-month period were collected at a single university medical center. Baseline demographic data, risk factor, microbiological data, recurrence of bacteremia, and mortality were recorded.

Results

A total of 177 patients were included in the analysis. MDR GNB occurred in 46 patients (26%). The mortality rate in the MDR group was 34.8% compared to 13.7% in non-MDR group (p = 0.002). In multivariate analysis, diabetes mellitus [DM; odds ratio (OR): 2.8, 95% confidence interval (CI): 1-4.88], previous antibiotic use (OR: 2.93, 95% CI: 1.25-6.87), and urinary catheter as a source of infection (OR 5.96, 95% CI: 1.78-19.94) were significant risk factors for the development of MDR GNB. In addition, end-stage liver disease (OR: 3.64, 95% CI: 1.07-12.3), solid organ malignancy (OR: 3.64, 95% CI: 1.25-10.56), intra-abdominal source of infection (OR: 3.66, 95% CI: 1.14-11.73), inappropriate empiric antibiotics (OR 7.59, 95% CI: 1.68-34.34) and urinary catheter as a source of infection (OR 5.68, 95% CI: 1.37-23.5) were significant factors for mortality in patients with MDR GNB.

Conclusion

Our study provides important information about the risk factors for the development of MDR GNB bacteremia and helps prognosticate patient with MDR GNB.

Pre-Engraftment Bloodstream Infections after Allogeneic Hematopoietic Cell Transplantation: Impact of T Cell-Replete Transplantation from a Haploidentical Donor

Bloodstream infections (BSIs) are frequent and important infectious complications after hematopoietic cell transplantation (HCT). The aim of this study was to analyze the incidence, risk factors, and outcome of pre-engraftment BSIs after allogeneic HCT. We retrospectively analyzed data from 553 consecutive patients who underwent HCT between 2010 and 2016. Sixty percent of the patients received T cell-replete unmanipulated haploidentical bone marrow with high-dose post-transplantation cyclophosphamide. The BSI rate was 30%; among isolated 213 pathogens, 54% were Gram-positive, 43% were Gram-negative, and 3% were fungi. Independent risk factors for pre-engraftment BSI were transplantation from a haploidentical donor or from cord blood (P < .001), active disease (P = .002), age (P = .04), and myeloproliferative disorders or aplastic anemia (P < .001). Transplantation from a haploidentical donor was an independent risk factor for both Gram-positive and Gram-negative BSI. The 7-day mortality after any BSI was 5% (9 of 178), and in multivariate analysis, BSI etiology was the sole risk factor, with increased mortality in carbapenem-resistant Gram-negative BSI (P < .001). Nonrelapse mortality at day +60 after HCT was 3.8% (21 of 553); independent predictors were active disease (P = .045), year of HCT (P = .027), nonengraftment (P = .001), and pre-engraftment BSI (P < .001), with significantly higher risk in BSI due to Gram-negative pathogens compared with Gram-positive pathogens, and BSI due to carbapenem-resistant Gram-negative pathogens compared with susceptible pathogens. Pre-engraftment BSI is a frequent complication after HCT from a haploidentical donor or cord blood. Because the negative impact of pre-engraftment BSI on 60-day nonrelapse mortality was caused mainly by carbapenem-resistant Gram-negative pathogens, particular attention should be given to appropriate empiric therapy and management of patients at high risk for Gram-negative BSI.

Antibiotic-Resistant Infections and Treatment Challenges in the Immunocompromised Host

This article reviews antibiotic resistance and treatment of bacterial infections in the growing number of patients who are immunocompromised: solid organ transplant recipients, the neutropenic host, and persons with human immunodeficiency virus and AIDS. Specific mechanisms of resistance in both gram-negative and gram-positive bacteria, as well as newer treatment options are addressed elsewhere, and are only briefly discussed in the context of the immunocompromised host.

Efficacy of β-Lactam/β-Lactamase Inhibitor Combinations for the Treatment of Bloodstream Infection Due to Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae in Hematological Patients with Neutropenia

β-Lactam/β-lactamase inhibitors (BLBLIs) were compared to carbapenems in two cohorts of hematological neutropenic patients with extended-spectrum-β-lactamase (ESBL) bloodstream infection (BSI): the empirical therapy cohort (174 patients) and the definitive therapy cohort (251 patients). The 30-day case fatality rates and other secondary outcomes were similar in the two therapy groups of the two cohorts and also in the propensity-matched cohorts. BLBLIs might be carbapenem-sparing alternatives for the treatment of BSI due to ESBLs in these patients.

Antimicrobial resistance patterns, clinical features, and risk factors for septic shock and death of nosocomial E coli bacteremia in adult patients with hematological disease: A monocenter retrospective study in China

The aim of this retrospective analysis was to evaluate the antimicrobial resistance, clinical features, and risk factors for septic shock and death of nosocomial E coli bacteremia in adult patients in a single hematological center in China. A retrospective case-control study of 157 adult hematological patients with 168 episodes of E coli bacteremia was initiated from April 2012 to July 2015. Antimicrobial susceptibility as well as antimicrobial co-resistance rates were analyzed. Clinical features and outcomes were also studied. In addition, risk factors for septic shock and death were investigated. Among the 553 positive blood isolates during the study period, the prevalence of E coli was 33.3% and ESBL production strains represented 61.9% of those examined. In all the E coli strains isolated, 85.6% were multidrug-resistance (MDR), 2.4% were extensive drug resistance (XDR), and 6.0% were resistant to carbapenems. More MDR phenotype was noted in ESBL-EC strains (98.6% vs 62.8%, P<.001) and isolates from neutropenic patients (98.6% vs 62.8%, P < .001). In the antimicrobial susceptibility test, carbapenems and amikacin exhibited not only higher in vitro activity against E coli (94.0% and 92.0%, respectively), but lower co-resistance rates to other antibiotics. Carbapenem resistant strains retained full sensitivity to tigecycline and 60% to amikacin. Piperacillin/tazobatam was the third sensitive drug to both ESBL-EC (77.1%) and non-ESBL-EC (86.0%). In our series, 81.6% episodes received appropriate initial antibiotic treatment and no significant decrease in it was found in bacteremia due to ESBL E coli and patients with neutropenia, septic shock. Septic shock was noted in 15.5% patients and the overall 30-day mortality rate was 21.7%. Multivariate analysis revealed that induction chemotherapy (OR 2.126; 95% CI 1.624-11.332; P = .003) and polymicrobial infection (OR 3.628; 95% CI 1.065-21.219; P = .041) were risk factors for septic shock, whereas male (OR 2.223; 95% CI 1.132-12.022; P < .01) and septic shock (OR 52.359; 95% CI 19.951-292.690; P = .030) were risk factors for death.In the hematology department, ESBL-producing and MDR are widely prevalent in E coli bacteremia which is still a major life-threatening problem, especially for patients with septic shock. For empirical antimicrobial therapy, combination based on aminoglycoside, especially amikacin, will be helpful to increase the antimicrobial coverage against ESBL-EC while combining tigecycline with aminoglycoside should be considered for seriously carbapenem-resistant infectious patients.

Bacteraemia due to AmpC β-lactamase-producing Escherichia coli in hospitalized cancer patients: risk factors, antibiotic therapy, and outcomes

AmpC β-lactamase-producing Escherichia coli (AmpC-EC) is one of the main antimicrobial resistant pathogens in patients with cancer. A cohort study was performed to evaluate the risk factors, antibiotic therapy, and outcomes of AmpC-EC bacteraemia in hospitalized cancer patients from September 2012 through December 2015. Two hundred forty-eight cases of E. coli bacteraemia were documented in cancer patients, 51 (20.6%) were caused by AmpC-EC and 197 (79.4%) were caused with non-AmpC-EC. Prior exposure to cephalosporins (OR 2.786; 95% CI: 1.094-7.091; P=0.032), carbapenems (OR 2.296; 95% CI: 1.054-5.004; P=0.036), and invasive procedures (OR 4.237; 95% CI: 1.731-10.37; P=0.002) were identified as independent risk factors for AmpC-EC. The time to positivity (TTP) of patients with AmpC-EC bacteraemia tended to be significantly shorter than that of non-AmpC-EC (8.33±2.18h versus 9.48±3.82h; P=0.006), and had a higher 30-day mortality rate in AmpC-EC compared with non-AmpC-EC (25.5% versus 12.2%; P=0.018). Metastasis (OR=2.778, 95% CI: 1.078-7.162; P=0.034), the presence of septic shock (OR=4.983, 95% CI: 1.761-14.10; P=0.002), and organ failure (OR=24.51 95% CI: 9.884-60.81; P<0.001) were independently associated with the overall mortality. The mortality rate showed a gradual increase when appropriate antibiotic therapy (AAT) was delayed more than 48h as determined by the trend test (P<0.001). In conclusion, this study showed that prevalence of AmpC-EC was high in hospitalized cancer patients of our area. Thus, it is necessary to apply appropriate therapeutic approaches and improve outcomes based on the analysis of risk factors for the acquisition of AmpC-EC.

Antimicrobial Activities of Ceftazidime-Avibactam and Comparator Agents against Clinical Bacteria Isolated from Patients with Cancer

A total of 521 unique clinical isolates from cancer patients with primarily (>90%) bloodstream infections were tested for susceptibility to ceftazidime-avibactam and comparators using broth microdilution methods. Ceftazidime-avibactam inhibited 97.8% of all Enterobacteriaceae (n = 321) at the susceptibility breakpoint of ≤8/4 μg/ml (there were 7 nonsusceptible strains). It was also active against Pseudomonas aeruginosa (91.7% isolates susceptible, n = 121), including many isolates not susceptible to meropenem, cefepime, ceftazidime, piperacillin-tazobactam, or other comparators.