Carbapenem-resistant Klebsiella pneumoniae is associated with poor outcome in hemodialysis patients

BACKGROUND

Hemodialysis (HD) units have become a source of resistant bacteria. One of the most alarming developments is the emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP). Risk factors and outcomes of CRKP isolation in HD patients have not been previously studied.

METHODS

A nested case-control study was conducted in maintenance HD patients between January 1st 2006 and June 30th 2009. CRKP-positive patients were matched with randomly selected CRKP-negative HD patients. Demographics, clinical and laboratory data were collected for 24 months prior to the specimen collection. Multivariate analyses identified independent risk factors for CRKP. A prospective follow-up determined CRKP-associated outcome.

RESULTS

Demographics associated with CRKP acquisition in HD patients were age between 65 and 75 and having no living offspring. Clinical conditions associated with CRKP were previous hospitalization, temporary HD catheter and previous isolation of vancomycin-resistant enterococcus. CRKP-related outcome was poor: median survival of one month and a hazard ratio [95% CI] of 5.9 [3.2-11.0] for mortality.

CONCLUSIONS

Temporary HD catheters and previous treatment for VRE may predict subsequent CRKP isolation. A microbiological diagnosis of CRKP in HD patients is highly associated with imminent mortality. Meticulous measures to control the spread of CRKP bacteria among HD patients appear particularly warranted.

Broadening the spectrum of β-lactam antibiotics through inhibition of signal peptidase type I

The resistance of methicillin-resistant Staphylococcus aureus (MRSA) to all β-lactam classes limits treatment options for serious infections involving this organism. Our goal is to discover new agents that restore the activity of β-lactams against MRSA, an approach that has led to the discovery of two classes of natural product antibiotics, a cyclic depsipeptide (krisynomycin) and a lipoglycopeptide (actinocarbasin), which potentiate the activity of imipenem against MRSA strain COL. We report here that these imipenem synergists are inhibitors of the bacterial type I signal peptidase SpsB, a serine protease that is required for the secretion of proteins that are exported through the Sec and Tat systems. A synthetic derivative of actinocarbasin, M131, synergized with imipenem both in vitro and in vivo with potent efficacy. The in vitro activity of M131 extends to clinical isolates of MRSA but not to a methicillin-sensitive strain. Synergy is restricted to β-lactam antibiotics and is not observed with other antibiotic classes. We propose that the SpsB inhibitors synergize with β-lactams by preventing the signal peptidase-mediated secretion of proteins required for β-lactam resistance. Combinations of SpsB inhibitors and β-lactams may expand the utility of these widely prescribed antibiotics to treat MRSA infections, analogous to β-lactamase inhibitors which restored the utility of this antibiotic class for the treatment of resistant Gram-negative infections.

Structures of Staphylococcus aureus peptide deformylase in complex with two classes of new inhibitors

Peptide deformylase (PDF) catalyzes the removal of the formyl group from the N-terminal methionine residue in newly synthesized polypeptides, which is an essential process in bacteria. Four new inhibitors of PDF that belong to two different classes, hydroxamate/pseudopeptide compounds [PMT387 (7a) and PMT497] and reverse-hydroxamate/nonpeptide compounds [PMT1039 (15e) and PMT1067], have been developed. These compounds inhibited the growth of several pathogens involved in respiratory-tract infections, such as Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae, and leading nosocomial pathogens such as Staphylococcus aureus and Klebsiella pneumoniae with a minimum inhibitory concentration (MIC) in the range 0.1-0.8 mg ml(-1). Interestingly, the reverse-hydroxamate/nonpeptide compounds showed a 250-fold higher antimicrobial activity towards S. aureus, although the four compounds showed similar K(i) values against S. aureus PDF enzymes, with K(i) values in the 11-85 nM range. To provide a structural basis for the discovery of additional PDF inhibitors, the crystal structures of S. aureus PDF in complex with the four inhibitors were determined at resolutions of 1.90-2.30 Å. The inhibitor-bound structures displayed distinct deviations depending on the inhibitor class. The distance between the Zn(2+) ion and the carbonyl O atom of the hydroxamate inhibitors (or the hydroxyl O atom of the reverse-hydroxamate inhibitors) appears to be correlated to S. aureus inhibition activity. The structural information reported in this study should aid in the discovery of new PDF inhibitors that can be used as novel antibacterial drugs.

Costs of healthcare- and community-associated infections with antimicrobial-resistant versus antimicrobial-susceptible organisms

OBJECTIVE

We compared differences in the hospital charges, length of hospital stay, and mortality between patients with healthcare- and community-associated bloodstream infections, urinary tract infections, and pneumonia due to antimicrobial-resistant versus -susceptible bacterial strains.

METHODS

A retrospective analysis of an electronic database compiled from laboratory, pharmacy, surgery, financial, and patient location and device utilization sources was undertaken on 5699 inpatients who developed healthcare- or community-associated infections between 2006 and 2008 from 4 hospitals (1 community, 1 pediatric, 2 tertiary/quaternary care) in Manhattan. The main outcome measures were hospital charges, length of stay, and mortality among patients with antimicrobial-resistant and -susceptible infections caused by Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii.

RESULTS

Controlling for multiple confounders using linear regression and nearest neighbor matching based on propensity score estimates, resistant healthcare- and community-associated infections, when compared with susceptible strains of the same organism, were associated with significantly higher charges ($15,626; confidence interval [CI], $4339-$26,913 and $25,573; CI, $9331-$41,816, respectively) and longer hospital stays for community-associated infections (3.3; CI, 1.5-5.4). Patients with resistant healthcare-associated infections also had a significantly higher death rate (0.04; CI, 0.01-0.08).

CONCLUSIONS

With careful matching of patients infected with the same organism, antimicrobial resistance was associated with higher charges, length of stay, and death rates. The difference in estimates after accounting for censoring for death highlight divergent social and hospital incentives in reducing patient risk for antimicrobial resistant infections.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 36 countries, for 2004-2009

The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia).

Murine typhus in Cyprus: a 9-year survey

Epidemiological and clinical data of 193 human cases of murine typhus in Cyprus were recorded and analysed during a 9-year period (2000-2008). The incidence rate was estimated at 24.5 cases/100,000 population/year. The incidence rate varied considerably between rural, urban and semi-urban areas, with residents in rural areas accounting for 79.3% of the total cases. Most (72.5%) of the cases occurred in late summer (July and August) and early autumn (September to October) with a peak in September. Well-established persistent endemic foci with clusters of cases were identified and characterised as 'high risk' areas. Presence of or contact with rats and fleas, presence of domestic/peridomestic animals and residence in rural areas, especially locations near the 'green line' (a narrow zone patrolled by UN forces that separates the northern and southern parts of the island), increased the possibility of murine typhus infection. The results of the current study enhance the belief that murine typhus is a serious public health problem in Cyprus.

Overview of adverse events related to invasive procedures in the intensive care unit

BACKGROUND

This study was conducted to determine the frequency, predictors, and clinical impact of adverse events (AEs) related to invasive procedures in the intensive care unit (ICU).

METHODS

This was a prospective observational study of ICUs in a university hospital.

RESULTS

A total of 893 patients requiring invasive procedures were admitted over a 1-year period. Among these, 310 patients (34.7%) experienced a total of 505 AEs. The mean number of AEs per patient was 1.6 ± 1.1 (range, 1-7). Infectious AEs were significantly more frequent than mechanical AEs (60.4% vs 39.6%; P = .01). Factors independently associated with AE occurrence were isolation of multidrug-resistant bacteria at ICU admission, >5 invasive procedures, and ICU length of stay >8 days. Thirty-three AEs (6.5%) resulted in severe clinical impact, including 24 deaths. Ventilator-associated pneumonia (VAP) accounted for 62.5% of the deaths related to AEs.

CONCLUSIONS

One-third of critically ill patients experienced AEs related to invasive procedures. Severe AEs were associated with 11% of all ICU deaths. VAP was the most frequent AE related to death. An improved assessment of the risk-benefit balance before each invasive procedure and increased efforts to decrease VAP prevalence are needed to reduce AE-related mortality.

Risk factors, molecular epidemiology and outcomes of ertapenem-resistant, carbapenem-susceptible Enterobacteriaceae: a case-case-control study

Background

Increasing prevalence of ertapenem-resistant, carbapenem-susceptible Enterobacteriaceae (ERE) in Singapore presents a major therapeutic problem. Our objective was to determine risk factors associated with the acquisition of ERE in hospitalized patients; to assess associated patient outcomes; and to describe the molecular characteristics of ERE.

Methods

A retrospective case-case-control study was conducted in 2009 at a tertiary care hospital. Hospitalized patients with ERE and those with ertapenem-sensitive Enterobacteriaceae (ESE) were compared with a common control group consisting of patients with no prior gram-negative infections. Risk factors analyzed included demographics; co-morbidities; instrumentation and antibiotic exposures. Two parallel multivariate logistic regression models were performed to identify independent variables associated with ERE and ESE acquisition respectively. Clinical outcomes were compared between ERE and ESE patients.

Results

Twenty-nine ERE cases, 29 ESE cases and 87 controls were analyzed. Multivariate logistic regression showed that previous hospitalization (Odds ratio [OR], 10.40; 95% confidence interval [CI], 2.19–49.20) and duration of fluoroquinolones exposure (OR, 1.18 per day increase; 95% CI, 1.05–1.34) were unique independent predictors for acquiring ERE. Duration of 4^th-generation cephalosporin exposure was found to predict for ESE acquisition (OR, 1.63 per day increase; 95% CI, 1.05–2.54). In-hospital mortality rates and clinical response rates were significantly different between ERE and ESE groups, however ERE infection was not a predictor of mortality. ERE isolates were clonally distinct. Ertapenem resistance was likely to be mediated by the presence of extended-spectrum β-lactamases or plasmid-borne AmpC in combination with impermeability due to porin loss and/or efflux pumps.

Conclusion

Prior hospitalization and duration of fluoroquinolone treatment were predictors of ERE acquisition. ERE infections were associated with higher mortality rates and poorer clinical response rates when compared to ESE infections.

Staphylococcal response to oxidative stress

Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous oxidative and nitrosative stress are often due to the bacteria's interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, we summarize the cellular targets of oxidative stress, the mechanisms by which staphylococci sense oxidative stress and damage, oxidative stress protection and repair mechanisms, and regulation of the oxidative stress response. When possible, special attention is given to how the oxidative stress defense mechanisms help staphylococci control oxidative stress in the host.

Hand hygiene in medical students: performance, education and knowledge

BACKGROUND

Despite several guidelines on hand hygiene (HH), compliance especially in physicians is reported to be low which has huge implications for healthcare-associated infections. To evaluate performance of HH, influence of teaching and influence of monitoring the results in medical students, we conducted an observational study.

METHODS

Performance of hand disinfection was evaluated in first (N=28), third (N=193) and fifth (N=45) year medical students using fluorescent hand disinfectant. The influence of teaching and information about result control was assessed. The students perception of the impact of HH was also evaluated by a questionnaire.

RESULTS

Presence of disinfectant gaps was observed significantly more often in first year medical students compared to third year ones (82% vs, 60%; p=0.02). In additional, > 3 gaps were seen significantly more often in first year medical students compared to fifth year students (36% vs. 9%; p=0.007). Both information about teaching and monitoring the results improved outcome significantly. For example, gaps were present in 92% without information and without teaching, in 70% (RR: 1.3 (1.0-1.6); p=0.003) with information about result control only, and in only 18% (5.1 (3.0-8.5); p=0.0001) after teaching. Notably, the medical students ascribed HH to be of a great importance regardless of their level of education.

CONCLUSIONS

Performance of HH could be improved by practical training as evidenced by best HH performance being documented immediately after teaching and a training effect during the course of medical studies was also observed. Thus, we suggest implementing regular education and practical training on HH from early on in the medical studies curricula to improve overall quality of patient care. regular education and practical training on HH from early on in the medical studies curricula to improve overall quality of patient care.

Impact of a multidimensional approach on ventilator-associated pneumonia rates in a hospital of Shanghai: findings of the International Nosocomial Infection Control Consortium

PURPOSE

The aim of this study was to analyze the impact of a multidimensional infection control approach on the reduction of ventilator-associated pneumonia (VAP) in intensive care units (ICUs) patients of one hospital in China.

MATERIALS AND METHODS

We conducted a before-after study from January 2005 to July 2009, which was divided into baseline (phase 1) and intervention (phase 2) periods. During phase 1, active prospective outcome surveillance of VAP was performed by applying the definitions of the Centers for Disease Control and Prevention/National Health Safety Network, and the methodology of the International Nosocomial Infection Control Consortium. During phase 2, the multidimensional approach was implemented. Ventilator-associated pneumonia rates obtained in phases 1 and 2 were compared in yearly periods.

RESULTS

We recorded data from 16,429 patients hospitalized in 3 ICUs, for a total of 74,116 ICU bed days. The VAP baseline rate was 24.1 per 1000 ventilator-days. During phase 2, the VAP rate significantly decreased to 5.7 per 1000 ventilator-days in 2009 (2009 vs 2005: relative risk, 0.31; 95% confidence interval, 0.16-0.36; P = .0001), amounting to a 79% cumulative VAP rate reduction.

CONCLUSIONS

Implementing a multidimensional infection control intervention for VAP was associated with a significant cumulative reduction in the VAP rate in our ICUs.

Risk factors for acquisition of extended-spectrum β-lactamase-producing Escherichia coli in an urban county hospital

BACKGROUND

Better characterization of risk factors for extended-spectrum β-lactamase (ESBL)-producing bacteria is important for prevention, control, and treatment. This study aimed to identify risk factors for ESBL-producing Escherichia coli in a population of patients at an acute care urban teaching hospital.

METHODS

A matched case-control study was performed. Cases comprised adults with ESBL E coli isolated from any source and matched with controls on year of hospitalization. One control group included patients with non-ESBL E coli, and a second control group consisted of patients with another resistant bacterium with well-characterized risk factors, Pseudomonas aeruginosa.

RESULTS

There were 93 subjects in each group. Risk factors associated with ESBL cases compared with both control groups in a univariate model included sex, age, comorbidity, health care facility residence, recent hospitalization, and hemodialysis. In multivariate analysis, only Charlson comorbidity score remained significant between the cases and both control groups. Recent receipt of antibiotics was a risk factor for ESBL E coli versus non-ESBL E coli but not versus P aeruginosa.

CONCLUSIONS

Underlying comorbid illness appears to be a robust risk factor for acquisition of ESBL-producing E coli. Antibiotic use is a less clear risk factor and may be a surrogate for health care exposure in general.

Secondary peritonitis caused by Streptomyces viridis

Streptomyces organisms are soil inhabitants rarely causing nonmycetomic infections. We describe a case of secondary peritonitis caused by Streptomyces viridis in a chronic alcoholic patient who presented with fever, abdominal distension, and pain in the abdomen. The most likely source of infection was by inoculation through multiple paracenteses, done for treatment of ascites, before the patient came to our health care center. This is the second case report of Streptomyces peritonitis and the first case caused by Streptomyces viridis, which is usually found in the soil in our geographic region.

Economic analysis of a pediatric ventilator-associated pneumonia prevention initiative in nicaragua

We performed an economic analysis of an intervention to decrease ventilator-associated pneumonia (VAP) prevalence in pediatric intensive care units (PICUs) at two Nicaraguan hospitals to determine the cost of the intervention and how effective it needs to be in order to be cost-neutral. A matched cohort study determined differences in costs and outcomes among ventilated patients. VAP cases were matched by sex and age for children older than 28 days and by weight for infants under 28 days old to controls without VAP. Intervention costs were determined from accounting and PICU staff records. The intervention cost was approximately $7,000 for one year. If VAP prevalence decreased by 0.5%, hospitals would save $7,000 and the strategy would be cost-neutral. The finding that the intervention required only modest effectiveness to be cost-neutral and has potential to generate substantial cost savings argues for implementation of VAP prevention strategies in low-income countries like Nicaragua on a broader scale.

Influence of parenteral nutrition delivery system on the development of bloodstream infections in critically ill patients: an international, multicenter, prospective, open-label, controlled study--EPICOS study

BACKGROUND

Parenteral nutrition (PN) is associated with an increased risk of developing bloodstream infections (BSIs) but the impact of the PN delivery system upon BSI rates remains unclear. This was an international, multicenter, prospective, randomized, open-label, controlled trial that investigated the differences of BSIs associated with 2 different PN systems.

METHODS

Patients were randomly allocated in a 2:1:1 ratio to receive either PN delivered by a multichamber bag (MCB group), or by compounded PN made with olive oil (COM1 group) or with MCT/LCT (COM2 group). Blood cultures were performed to evaluate the incidence of BSIs, and catheter use data was collected to calculate CLAB and central venous catheter device use ratio (CVC-DUR). Secondary outcomes included the development of severe sepsis/septic shock, number of intensive care unit (ICU) and hospital days, and all-cause mortality at Day 28.

RESULTS

406 patients were included: 202 in the MCB group, 103 in the COM1 group, and 101 in the COM2 group. Baseline characteristics were well balanced between the 3 groups, BSIs were significantly higher in patients receiving compounded PN (46 BSIs for COM1+COM2 vs 34 BSIs for MCB; p = 0.03).CLAB was higher in patients receiving compounded PN (13.2 for COM1+COM2 vs 10.3 for MCB; p < 0.0001). No differences were observed for the secondary outcomes.

CONCLUSION

Compounded PN was associated with a higher incidence of BSIs and CLABs, suggesting that the use of MCB PN may play a role in reducing the incidence of BSIs in patients who receive PN.

TRIAL REGISTRATION NUMBER

NCT00798681.

Antimicrobial and anticoagulant activities of N-chlorotaurine, N,N-dichloro-2,2-dimethyltaurine, and N-monochloro-2,2-dimethyltaurine in human blood

The aim of this study was to determine the potential application of N-chlorotaurine (NCT), N,N-dichloro-2,2-dimethyltaurine (NVC-422), and N-monochloro-2,2-dimethyltaurine (NVC-612) as catheter lock solutions for the prevention of catheter blockage and catheter-related bloodstream infections by testing their anticoagulant and broad-spectrum antimicrobial activities in human blood. NCT, NVC-422, NVC-612, and control compounds were serially diluted in fresh human blood to evaluate the effects on prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, and direct thrombin inhibition. Quantitative killing assays against pathogens, including methicillin-resistant Staphylococcus aureus, Escherichia coli, and Candida albicans, were performed in the presence of heparin and human blood. NCT and NVC-612 (1.38 mM each) and 1.02 mM NVC-422 prolonged prothrombin time (Quick value, 17 to 30%), activated partial thromboplastin time 3- to 4-fold to 76 to 125 s, and thrombin time 2- to 4-fold to 34 to 68 s. Fibrinogen decreased from 258 to 283 mg/dl (range of controls) to <40 mg/dl. No direct thrombin inhibition was observed by NVC-422 or NVC-612. Heparin did not influence the bactericidal activity of NCT. The microbicidal activities of NCT, NVC-422, and NVC-612 were maintained in diluted human blood. NCT, NVC-612, and NVC-422 have broad-spectrum antimicrobial activity in blood and anticoagulant activity targeting both intrinsic and extrinsic pathways of the coagulation system. These properties support their application as catheter lock solutions.

Active and passive immunization protects against lethal, extreme drug resistant-Acinetobacter baumannii infection

Extreme-drug-resistant (XDR) Acinetobacter baumannii is a rapidly emerging pathogen causing infections with unacceptably high mortality rates due to inadequate available treatment. New methods to prevent and treat such infections are a critical unmet medical need. To conduct a rational vaccine discovery program, OmpA was identified as the primary target of humoral immune response after intravenous infection by A. baumannii in mice. OmpA was >99% conserved at the amino acid level across clinical isolates harvested between 1951 and 2009 from cerebrospinal fluid, blood, lung, and wound infections, including carbapenem-resistant isolates, and was ≥89% conserved among other sequenced strains, but had minimal homology to the human proteome. Vaccination of diabetic mice with recombinant OmpA (rOmpA) with aluminum hydroxide adjuvant markedly improved survival and reduced tissue bacterial burden in mice infected intravenously. Vaccination induced high titers of anti-OmpA antibodies, the levels of which correlated with survival in mice. Passive transfer with immune sera recapitulated protection. Immune sera did not enhance complement-mediated killing but did enhance opsonophagocytic killing of A. baumannii. These results define active and passive immunization strategies to prevent and treat highly lethal, XDR A. baumannii infections.

Empiric antibiotic selection strategies for healthcare-associated pneumonia, intra-abdominal infections, and catheter-associated bacteremia

Initial selection and early deployment of appropriate/adequate empiric antimicrobial therapy is critical to minimize the significant morbidity and mortality associated with hospital- or healthcare-associated infections (HAIs). Initial empiric therapy that inadequately covers the pathogen(s) causing a serious HAI has been associated with increased mortality, longer hospital stay, and elevated healthcare costs. Moreover, subsequent modification of initial inadequate therapy, later in the disease process when culture results become available, may not remedy the impact of the initial choice. Because of this, it is important that initial empiric therapy covers the most likely pathogens associated with infection in a particular patient, even if this initial regimen turns out to be unnecessarily broad, based on subsequent culture results. The current paradigm for management of serious HAIs is to initiate empiric therapy with a broad-spectrum regimen covering likely pathogens, based on local surveillance and susceptibility data, and presence of risk factors for involvement of a resistant microorganism. Subsequent modification (de-escalation) of the initial regimen becomes possible later, when culture results are available and clinical status can be better assessed, 2 to 4 days after initiation of empiric therapy. When possible, de-escalation and other steps to modify antimicrobial exposure are important for minimizing risk of antimicrobial resistance development. This article examines the general process for selection of initial empiric antibiotic therapy for patients with HAIs, illustrated through 3 case studies dealing with healthcare-associated pneumonia, complicated intra-abdominal infection, and catheter-associated bacteremia, respectively.

Identification of genotypes of plasmid-encoded AmpC beta-lactamases from clinical isolates and characterization of mutations in their promoter and attenuator regions

We investigated the occurrence of AmpC beta-lactamases among Escherichia coli and Klebsiella pneumoniae isolates and determined the genotype of plasmid-mediated AmpC beta-lactamases at a medical center. The AmpC beta-lactamase promoter and attenuator were amplified from chromosomal DNA of high AmpC-producing E. coli isolates and sequenced. Antibiotic screening and 3D extract tests showed the presence of AmpC beta-lactamase in 3.56% of K. pneumoniae and 1.88% of E. coli isolates. Ten isolates (six K. pneumoniae and four E. coli) were positive for extended spectrum beta-lactamase (ESBL) as indicated by the double disc diffusion method. DHA-1 plasmid-encoded AmpC beta-lactamase was present in 10 K. pneumoniae isolates and four E.coli isolates. E. coli chromosomal AmpC beta-lactamase carried polymorphisms in the -42, -32, and -18 bases of the promoter and in the +26 and +27 bases of the attenuator, which may play a role in antibiotic resistance. The observed mutations may have clinical implications for the management of antibiotic-resistant infections.

Is 27 really a dangerous age for famous musicians? Retrospective cohort study

OBJECTIVE

To test the "27 club" hypothesis that famous musicians are at an increased risk of death at age 27. Design Cohort study using survival analysis with age as a time dependent exposure. Comparison was primarily made within musicians, and secondarily relative to the general UK population.

SETTING

The popular music scene from a UK perspective.

PARTICIPANTS

Musicians (solo artists and band members) who had a number one album in the UK between 1956 and 2007 (n = 1046 musicians, with 71 deaths, 7%).

MAIN OUTCOME MEASURES

Risk of death by age of musician, accounting for time dependent study entry and the number of musicians at risk. Risk was estimated using a flexible spline which would allow a bump at age 27 to appear.

RESULTS

We identified three deaths at age 27 amongst 522 musicians at risk, giving a rate of 0.57 deaths per 100 musician years. Similar death rates were observed at ages 25 (rate = 0.56) and 32 (0.54). There was no peak in risk around age 27, but the risk of death for famous musicians throughout their 20s and 30s was two to three times higher than the general UK population.

CONCLUSIONS

The 27 club is unlikely to be a real phenomenon. Fame may increase the risk of death among musicians, but this risk is not limited to age 27.

Is screening patients for antibiotic-resistant bacteria justified in the Indian context?

Infection with multi-antibiotic-resistant bacteria is a common clinical problem in India. In some countries and centres, screening patients to detect colonisation by these organisms is used to determine specific interventions such as decolonisation treatment, prophylactic antibiotics prior to surgical interventions or for selection of empirical antibiotic therapy, and to isolate patients so that transmission of these difficult to treat organisms to other patients could be prevented. In India, there is no national guideline or recommendation for screening patients for multi-drug-resistant (MDR) bacteria such as MRSA (methicillin-resistant Staphylococcus aureus), VRE (vancomycin-resistant enterococcus), ESBL (extended spectrum beta-lactamase) or MBL (metallo-beta-lactamase) producers. The present article discusses the relevance of screening patients for multi-antibiotic-resistant bacteria in the Indian context. Literature has been reviewed about antibiotic resistance in India, screening methodology, economic debate about screening. The percentages of strains from various hospitals in India which were reported to be MRSA was between 8 and 71%, those for ESBL between 19 and 60% and carbapenem-resistant Gram-negative bacilli between 5.3 and 59%. There exists culture-based technology for the detection of these resistant organisms from patient samples. For some pathogens, such as MRSA and VRE Polymerase chain reaction-based tests are also becoming available. Screening for MDR bacteria is an option which may be used after appraisal of the resources available, and after exploring possibility of implementing the interventions that may be required after a positive screening test result.

Q-fever can simulate a lupus flare

Fever is a diagnostic challenge in the patient with lupus. Infections can mimic a lupus flare which further complicates the diagnostic approach. Moreover, immunosuppressive treatment of SLE may promote the development of infections and poor outcome. We report the case of a patient with SLE with an initial diagnosis of lupus flare, who was found to have Q fever showing an excellent response to treatment with doxycycline.

Emergence of New Delhi metallo-beta-lactamase (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC-2) in South Africa

This report documents emergence of New Delhi metallo-beta-lactamase (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC-2) in K. pneumoniae and Enterobacter cloacae in South Africa. NDM-1 producers have not been described in South Africa, and this is the first instance that KPC producers have been identified in Africa. The two patients infected with these carbapenemase-producing bacteria demised.

When and how to cover for resistant gram-negative bacilli in severe sepsis and septic shock

In the 80s and 90s, increasing antibiotic resistance was met by the introduction of new effective agents with broader antibacterial spectra for the empirical treatment of severe infections. In recent years, however, few novel antimicrobials have been developed, and this has critically weakened our strength in the fight against resistant bacteria, especially Gram-negative bacilli. It has been well proven that mortality increases if initial empirical antibiotic treatment for severe infection is inappropriate due to resistance of the pathogen. Physicians are already faced with the increasing challenge of untreatable or almost untreatable Gram-negative infections due to antibiotic resistance. Empirical treatment with broader spectra and high antibiotic pressure both in- and outside hospital is the driving force behind resistance. Since new efficient drugs against Gram-negative bacilli will not be available for some time, the best we can do to stop infections caused by multidrug-resistant bacteria is to improve infection control and choice of antibiotics, which should be based on surveillance of local antibiotic consumption and resistance. We must learn more about the revived antibacterial agents colistin and fosfomycin, and the few next generation Gram-negative antibiotics that have been developed. The aim of this review is to give an update on present therapeutic options in the fight against multidrug-resistant Gram-negative bacteria.

Time-dependent analysis of extra length of stay and mortality due to ventilator-associated pneumonia in intensive-care units of ten limited-resources countries: findings of the International Nosocomial Infection Control Consortium (INICC)

Ventilator-associated pneumonias (VAPs) are a worldwide problem that significantly increases patient morbidity, mortality, and length of stay (LoS), and their effects should be estimated to account for the timing of infection. The purpose of the study was to estimate extra LoS and mortality in an intensive-care unit (ICU) due to a VAP in a cohort of 69,248 admissions followed for 283,069 days in ICUs from 10 countries. Data were arranged according to the multi-state format. Extra LoS and increased risk of death were estimated independently in each country, and their results were combined using a random-effects meta-analysis. VAP prolonged LoS by an average of 2·03 days (95% CI 1·52-2·54 days), and increased the risk of death by 14% (95% CI 2-27). The increased risk of death due to VAP was explained by confounding with patient morbidity.

Hand hygiene in pediatric and neonatal intensive care unit patients: daily opportunities and indication- and profession-specific analyses of compliance

BACKGROUND

Hand hygiene is considered to be the single most effective tool to prevent health care-associated infections. Daily hand hygiene opportunities and compliance for pediatric/neonatal intensive care units (ICU) are currently unknown.

METHODS

This was a prospective observational study in pediatric and neonatal ICU patients with analyses of hand hygiene behavior in relation to profession, indication, and shift and correlation with disinfectant usage.

RESULTS

Hand hygiene opportunities were significantly higher for pediatric (321/24 hours) than neonatal (194/24 hours; P = .024) patients. Observed compliance rates were 53% (pediatric) and 61% (neonatal) and found to be significantly higher in nurses (57%; 66%) than in physicians (29%, 52%, respectively; P < .001; P = .017, respectively). For neonates, compliance rates were significantly higher before patient contact and aseptic tasks (78%) than after patient, patient body fluid, or patients' surrounding contact (57%; P < .001). Calculating disinfectant usage revealed a 3-fold lower compliance rate of 17%.

CONCLUSION

This study provides the first data on opportunities for and compliance with hand hygiene in pediatric/neonatal patients encompassing the whole day and night activities and including a comparison of observed and calculated compliance rates. Observation revealed high compliance especially in nurses and in situations of greatest impact. The data provide a detailed characterization of hand hygiene performance in the neonatal/pediatric ICU setting.

[Factors that contribute to health care associated infections: how to prevent them]

OBJECTIVE

To determine the patient and medical care characteristics of Health Care-Associated Infections (HCAI) and to determine whether or not there are any differences between those that may be avoidable.

METHOD

A retrospective cohort study, based on three Spanish cohort studies of Adverse Events associated with hospitalization. The medical records were reviewed to assess whether or not the health care was the causing factor of the HCAI. We carried out the analyses using the same methodology as the National Study on the Adverse Effects associated with hospitalization (ENEAS). After reviewing the patient medical records to identify the HCAI associated factors, the reviewers gave a valued judgment on how likely the health care was the cause of the infection (HCAI) and whether there was evidence that they could have been avoided.

RESULTS

A total of 2.3% the patients in the study had one or more HCAI, with 60.2% of them being avoidable. The patients who had an HCAI were older and had a greater number of intrinsic and extrinsic risk factors. There was a significant difference in the presence of some intrinsic risk factor between patients who had an HCAI and those with an avoidable HCAI, but there were no differences as regards medical care extrinsic risk factors. The factors that best explained the HCAI were different for each one of the most common infection locations. Generally, the factors which best explained the HCAI were: urinary catheter (OR=2.4), nasogastric tube (OR=1.9) or central venous catheter (OR=1.8). Similarly, hospital admissions through a surgery department or a hospital stay longer than a week were identified as main factors, (OR=1.6), (OR=7.5), respectively. The best strategies to avoid an HCAI were: proper management of any aseptic technique and use of catheter (25.5%), a proper follow-up of the bladder catheterisation protocols (20%) and a proper health care follow-up of vulnerable patients (16.5%).

CONCLUSION

Patients with an HCAI showed significant different characteristics from those who did not have an HCAI. The preventability is an independent valued judgment from the causality, and is associated to whether the proper protocol has been implemented or not. To identify these weaknesses enables us to establish strategies to improve the quality of medical care.

Effectiveness of a hand hygiene promotion strategy using alcohol-based handrub in 6 intensive care units in Colombia

BACKGROUND

Hand hygiene is an effective strategy for the prevention of health care-associated infection (HAI). We investigated the effect of a hand hygiene promotion strategy introducing alcohol-based handrub (AHBR) on the incidence of HAI in a university hospital in Colombia.

METHODS

A Prospective cohort study was performed in 6 intensive care units from January 2001 to December 2005. HAI were identified using standard US Centers for Disease Control and Prevention definitions. Alcohol-based handrub dispensers were installed between February and June 2002.

RESULTS

Total ABHR consumption was 5,794 L (mean, 28.9 L per 1,000 patient-days) and significantly increased over time (+9.2% per year; P < .001). Of 14,516 patients cumulating 166,498 patient-days, 2,398 (16.5%) acquired a total of 3,490 HAI episodes (20.9 per 1,000 patient-days). Incidence densities for central line-associated bloodstream infection (CLABSI), ventilator-associated pneumonia, and urinary tract infections were 7.7, 10.6, and 3.6 episodes per 1,000 device-days, respectively. A significant decrease was observed for CLABSI (-12.7% per year; P < .001) with low nurse-to-patient ratio independently associated with infection (odds ratio, 1.11; 95% confidence interval: 1.07-1.16; P < .001).

CONCLUSION

Improved hand hygiene measured by increased ABHR consumption resulted in CLABSI reduction. Low nurse-to-patient ratio is independently associated with HAI in an upper-middle income country.

Socioeconomic impact on device-associated infections in limited-resource neonatal intensive care units: findings of the INICC

PURPOSE

To evaluate the impact of country socioeconomic status and hospital type on device-associated healthcare-associated infections (DA-HAIs) in neonatal intensive care units (NICUs).

METHODS

Data were collected on DA-HAIs from September 2003 to February 2010 on 13,251 patients in 30 NICUs in 15 countries. DA-HAIs were defined using criteria formulated by the Centers for Disease Control and Prevention. Country socioeconomic status was defined using World Bank criteria.

RESULTS

Central-line-associated bloodstream infection (CLA-BSI) rates in NICU patients were significantly lower in private than academic hospitals (10.8 vs. 14.3 CLA-BSI per 1,000 catheter-days; p < 0.03), but not different in public and academic hospitals (14.6 vs. 14.3 CLA-BSI per 1,000 catheter-days; p = 0.86). NICU patient CLA-BSI rates were significantly higher in low-income countries than in lower-middle-income countries or upper-middle-income countries [37.0 vs. 11.9 (p < 0.02) vs. 17.6 (p < 0.05) CLA-BSIs per 1,000 catheter-days, respectively]. Ventilator-associated-pneumonia (VAP) rates in NICU patients were significantly higher in academic hospitals than in private or public hospitals [13.2 vs. 2.4 (p < 0.001) vs. 4.9 (p < 0.001) VAPs per 1,000 ventilator days, respectively]. Lower-middle-income countries had significantly higher VAP rates than low-income countries (11.8 vs. 3.8 per 1,000 ventilator-days; p < 0.001), but VAP rates were not different in low-income countries and upper-middle-income countries (3.8 vs. 6.7 per 1,000 ventilator-days; p = 0.57). When examined by hospital type, overall crude mortality for NICU patients without DA-HAIs was significantly higher in academic and public hospitals than in private hospitals (5.8 vs. 12.5%; p < 0.001). In contrast, NICU patient mortality among those with DA-HAIs was not different regardless of hospital type or country socioeconomic level.

CONCLUSIONS

Hospital type and country socioeconomic level influence DA-HAI rates and overall mortality in developing countries.

Molecular evidence for Anaplasma phagocytophilum in Ixodes ricinus ticks from Greece

Human granulocytic anaplasmosis is increasingly being recognized in the United States and Europe. Ixodes ricinus tick is considered the primary vector of the causative pathogen, Anaplasma phagocytophilum, in Europe. Although previous studies in humans support the presence of A. phagocytophilum in Greece, detection of A. phagocytophilum DNA in I. ricinus ticks has been not yet reported. A total of 405 I. ricinus ticks (45 pools) collected from goats in eight prefectures of northern Greece were tested for the presence of A. phagocytophilum DNA. Four pools of ticks collected in three prefectures revealed a sequence with 99%-100% similarity to known A. phagocytophilum sequences, providing the first molecular evidence for the circulation of A. phagocytophilum in I. ricinus ticks in Greece.

Q fever: a new ocular manifestation

Q Fever is a zoonosis caused by Coxiella burnetii. Ocular manifestations are rare in this infection. We describe the case of a man complaining of an intense retro-orbital headache, fever, arthralgia, and bilateral loss of vision, who showed an anterior uveitis accompanied by exudative bilateral inferior retinal detachment and optic disk edema. At the beginning, a Vogt-Koyanagi-Harada (VKH) syndrome was suspected, but the patient was diagnosed with Q fever and treatment with doxycycline was initiated, with complete resolution after 2 weeks. We wondered if Q fever could unleash VKH syndrome or simulate a VKH syndrome by a similar immunological process.

Editorial: Transforming global health, global health education, infectious disease, and chronic conditions in the 21st century

Chronic and infectious diseases, including health care-associated infections and tropical diseases, represent a large portion of the global health burden. Solutions need to be found while addressing other health priorities identified by the Millennium Development Goals. A number of organizations and initiatives have been created to meet this need. Developing countries in Latin America and several African countries are taking a larger role in the development of robust health systems, capacity building, and education. Integrated, efficient, and equitable health systems that incorporate primary, secondary, and tertiary care models with a research focus are critically needed to fill this void.

Further increases in carbapenem-, amikacin-, and fluoroquinolone-resistant isolates of Acinetobacter spp. and P. aeruginosa in Korea: KONSAR study 2009

PURPOSE

The increasing prevalence of antimicrobial resistant bacteria has become a serious worldwide problem. The aim of this study was to analyze antimicrobial resistance data generated in 2009 by hospitals and commercial laboratories participating in the Korean Nationwide Surveillance of Antimicrobial Resistance program.

MATERIALS AND METHODS

Susceptibility data were collected from 24 hospitals and two commercial laboratories. In the analysis, resistance did not include intermediate susceptibility. Duplicate isolates were excluded from the analysis of hospital isolates, but not from the commercial laboratory isolates.

RESULTS

Among the hospital isolates, methicillin-resistant Staphylococcus aureus, penicillin G-nonsusceptible Streptococcus pneumoniae based on meningitis breakpoint, and ampicillin- resistant Enterococcus faecium remained highly prevalent. The proportion of vancomycin-resistant E. faecium gradually increased to 29%. Ceftazidime-resistant Escherichia coli and Klebsiella pneumoniae increased to 17% and 33%, respectively, and fluoroquinolone-resistant K. pneumoniae, Acinetobacter spp. and Pseudomonas aeruginosa increased to 33%, 67% and 39%, respectively. Amikacin-resistant Acinetobacter spp. increased to 48%. Imipenem-resistant Acinetobacter spp. and P. aeruginosa increased to 51% and 26%, respectively. Higher resistance rates were observed in intensive care unit (ICU) isolates than in non-ICU isolates among the isolates from hospitals. Resistance rates were higher in hospital isolates than in clinic isolates among the isolates from commercial laboratories.

CONCLUSION

Among the hospital isolates, ceftazidime-resistant K. pneumoniae and fluoroquinolone- resistant K. pneumoniae, Acinetobacter spp., and P. aeruginosa further increased. The increase in imipenem resistance was slight in P. aeruginosa, but drastic in Acinetobacter spp. The problematic antimicrobial-organism combinations were much more prevalent among ICU isolates.

Device-associated infections rates in adult, pediatric, and neonatal intensive care units of hospitals in the Philippines: International Nosocomial Infection Control Consortium (INICC) findings

BACKGROUND

This study investigated the rate of device-associated health care-associated infection (DA-HAI), microbiological profiles, bacterial resistance, length of stay (LOS), and mortality rate in 9 intensive care units (ICUs) of 3 hospital members of the International Nosocomial Infection Control Consortium (INICC) in the Philippines.

METHODS

This was an open-label, prospective cohort, active DA-HAI surveillance study of adult, pediatric, and newborn patients admitted to 9 tertiary care ICUs in the Philippines between January 2005 and December 2009, implementing methodology developed by the INICC. Data collection was performed in the participating ICUs, and data were uploaded and analyzed at the INICC headquarters using proprietary software. DA-HAI rates were registered based on definitions promulgated by the Centers for Disease Control and Prevention's National Healthcare Safety Network.

RESULTS

Over a 5-year period, 4952 patients hospitalized in ICUs for a total of 40,733 days acquired 199 DA-HAIs, for an overall rate of 4.9 infections per 1,000 ICU-days. Ventilator-associated pneumonia posed the greatest risk (16.7 per 1,000 ventilator-days in the adult ICUs, 12.8 per 1,000 ventilator-days in the pediatric ICU, and 0.44 per 1,000 ventilator-days in the neonatal ICUs), followed by central line-associated bloodstream infections (4.6 per 1,000 catheter-days in the adult ICUs, 8.23 per 1,000 ventilator-days in the pediatric ICU, and 9.6 per 1,000 ventilator-days in the neonatal ICUs) and catheter-associated urinary tract infections (4.2 per 1,000 catheter-days in the adult ICUs and 0.0 in the pediatric ICU).

CONCLUSION

DA-HAIs pose far greater threats to patient safety in Philippine ICUs than in US ICUs. The establishment of active infection control programs that involve infection surveillance and implement guidelines for prevention can improve patient safety and should become a priority.

Guideline-adherent initial intravenous antibiotic therapy for hospital-acquired/ventilator-associated pneumonia is clinically superior, saves lives and is cheaper than non guideline adherent therapy

INTRODUCTION

Hospital-acquired pneumonia (HAP) often occurring as ventilator-associated pneumonia (VAP) is the most frequent hospital infection in intensive care units (ICU). Early adequate antimicrobial therapy is an essential determinant of clinical outcome. Organisations like the German PEG or ATS/ IDSA provide guidelines for the initial calculated treatment in the absence of pathogen identification. We conducted a retrospective chart review for patients with HAP/VAP and assessed whether the initial intravenous antibiotic therapy (IIAT) was adequate according to the PEG guidelines.

MATERIALS AND METHODS

We collected data from 5 tertiary care hospitals. Electronic data filtering identified 895 patients with potential HAP/VAP. After chart review we finally identified 221 patients meeting the definition of HAP/VAP. Primary study endpoints were clinical improvement, survival and length of stay. Secondary endpoints included duration of mechanical ventilation, total costs, costs incurred on the intensive care unit (ICU), costs incurred on general wards and drug costs.

RESULTS

We found that 107 patients received adequate initial intravenous antibiotic therapy (IIAT) vs. 114 with inadequate IIAT according to the PEG guidelines. Baseline characteristics of both groups revealed no significant differences and good comparability. Clinical improvement was 64% over all patients and 82% (85/104) in the subpopulation with adequate IIAT while only 47% (48/103) inadequately treated patients improved (p< 0.001). The odds ratio of therapeutic success with GA versus NGA treatment was 5.821 (p<0.001, [95% CI: 2.712-12.497]). Survival was 80% for the total population (n = 221), 86% in the adequately treated (92/107) and 74% in the inadequately treated subpopulation (84/114) (p = 0.021). The odds ratio of mortality for GA vs. NGA treatment was 0.565 (p=0.117, [95% CI: 0.276-1.155]). Adequately treated patients had a significantly shorter length of stay (LOS) (23.9 vs. 28.3 days; p = 0.022), require significantly less hours of mechanical ventilation (175 vs. 274; p = 0.001), incurred lower total costs (EUR 28,033 vs. EUR 36,139, p = 0.006) and lower ICU-related costs (EUR 13,308 vs. EUR 18,666, p = 0.003). Drug costs for the hospital stay were also lower (EUR 4,069 vs. EUR 4,833) yet not significant. The most frequent types of inadequate therapy were monotherapy instead of combination therapy, wrong type of penicillin and wrong type of cephalosporin.

DISCUSSION

These findings are consistent with those from other studies analyzing the impact of guideline adherence on survival rates, clinical success, LOS and costs. However, inadequately treated patients had a higher complicated pathogen risk score (CPRS) compared to those who received adequate therapy. This shows that therapy based on local experiences may be sufficient for patients with low CPRS but inadequate for those with high CPRS. Linear regression models showed that single items of the CPRS like extrapulmonary organ failure or late onset had no significant influence on the results.

CONCLUSION

Guideline-adherent initial intravenous antibiotic therapy is clinically superior, saves lives and is less expensive than non guideline adherent therapy. Using a CPRS score can be a useful tool to determine the right choice of initial intravenous antibiotic therapy. The net effect on the German healthcare system per year is estimated at up to 2,042 lives and EUR 125,819,000 saved if guideline-adherent initial therapy for HAP/VAP were established in all German ICUs.

Effectiveness of comprehensive implementation of individualized bundling infection control measures for prevention of health care-associated infections in general medical wards

BACKGROUND

The prevalence of health care-associated infections (HAIs) in general medical wards at Siriraj Hospital in Bangkok, Thailand remains at 10% even after infection control measures were launched. The present study aimed to determine the effectiveness of comprehensive individualized bundling infection control measures in reducing HAIs and to identify the lowest possible rate of HAIs in general medical wards.

METHODS

This was a cluster randomized controlled study conducted in 8 general medical wards (4 control wards and 4 intervention wards) at Siriraj Hospital. The patients hospitalized in the control wards received regular health care, as well as regular measures for preventing HAIs. The patients hospitalized in the intervention wards received additional measures. Each patient in the intervention wards was visited by the infection control team once a day until he or she left the hospital. The infection control team identified risk factors for developing HAI in each patient, coordinated with the local health care team to eliminate or minimize such risk factors, and encouraged responsible personnel to comply with the appropriate infection control measures for each patient.

RESULTS

Between January and April 2009, there were 954 patients (9,650 hospitalization-days) in the intervention wards and 920 patients (9,777 hospitalization-days) in the control wards. The patient characteristics were comparable in the 2 groups. The prevalence of HAI was significantly lower in the intervention wards compared with the control wards (5.6% vs. 9.2%; P = .003). Six episodes of HAI in patients in the intervention wards could have been avoided.

CONCLUSION

Comprehensive individualized bundling infection control measures were effective in reducing the prevalence of HAIs in general medical wards. The target overall prevalence of HAIs in general medical wards should not exceed 4.9%.