Growth and geographic variation in hospitalizations with resistant infections, United States, 2000-2005

The Prevalence and Molecular Biology of Staphylococcus aureus Isolated from Healthy and Diseased Equine Eyes in Egypt

This work aimed to characterize S. aureus isolates from the eyes of healthy and clinically affected equines in the Kafrelsheikh Governorate, Egypt. A total of 110 animals were examined for the presence of S. aureus, which was isolated from 33 animals with ophthalmic lesions and 77 healthy animals. We also investigated the antimicrobial resistance profile, oxacillin resistance mechanism, and the major virulence factors implicated in many studies of the ocular pathology of pathogenic S. aureus. The association between S. aureus eye infections and potential risk factors was also investigated. The frequency of S. aureus isolates from clinically affected equine eyes was significantly higher than in clinically healthy equids. A significant association was found between the frequency of S. aureus isolation from clinically affected equine eyes and risk factors including age and season but not with sex or breed factors. Antimicrobial resistance to common antibiotics used to treat equine eyes was also tested. Overall, the isolates showed the highest sensitivity to sulfamethoxazole (100%) and the highest resistance to cephalosporin (90.67%) and oxacillin (90.48%). PCR was used to demonstrate that mecA was present in 100% of oxacillin- and β-lactam-resistant S. aureus strains. The virulence factor genes Spa (x region), nuc, and hlg were identified in 62.5%, 100%, and 56%, of isolates, respectively, from clinically affected equines eyes. The severity of the eye lesions increased in the presence of γ-toxin-positive S. aureus. The phylogenetic tree of the Spa (x region) gene indicated a relationship with human reference strains isolated from Egypt as well as isolates from equines in Iran and Japan. This study provides insight into the prevalence, potential risk factors, clinical pictures, zoonotic potential, antimicrobial resistance, and β-lactam resistance mechanism of S. aureus strains that cause eye infection in equines from Egypt.

Economic Burden of Urinary Tract Infections From Antibiotic-Resistant Escherichia coli Among Hospitalized Adult Patients in Lebanon: A Prospective Cohort Study

OBJECTIVES

The rising incidence of urinary tract infections (UTIs) attributable to Escherichia coli resistant isolates is becoming a serious public health concern. Although global rates of infection vary considerably by region, the growing prevalence of this uropathogen has been associated with a high economic burden and health strain. This study aims: (1) to estimate the differences in clinical and economic outcomes between 2 groups of adult hospitalized patients with UTIs from E. coli resistant and susceptible bacteria and (2) to investigate drivers of this cost from a payer's perspective.

METHODS

A prospective multicenter cohort study was conducted in 10 hospitals in Lebanon. The cost analysis followed a bottom-up microcosting approach; a linear regression was constructed to evaluate the predictors of hospitalization costs and a Cox proportional hazards model was used to estimate the impact of resistance on length of stay (LOS) and in-hospital mortality.

RESULTS

Out of 467 inpatients, 250 cases were because of resistant E. coli isolates. Results showed that patients with resistant uropathogens had 29% higher mean total hospitalization costs ($3429 vs $2651; P = .004), and an extended median LOS (6 days vs 5 days; P = .020) compared with susceptible cohorts. The selection of resistant bacteria and the Charlson comorbidity index predicted higher total hospitalization costs and in-hospital mortality.

CONCLUSION

In an era of increased pressure for cost containment, this study showed the burden of treating UTIs resulting from resistant bacteria. The results can inform cost-effectiveness analyses that intend to evaluate the benefit of a national action plan aimed at decreasing the impact of antibiotic resistance.

Improving Care and Outcomes for Pediatric Musculoskeletal Infections

BACKGROUND

Pediatric musculoskeletal infection (MSKI) is a common cause of hospitalization with associated morbidity. To improve the care of pediatric MSKI, our objectives were to achieve 3 specific aims within 24 months of our quality improvement (QI) interventions: (1) 50% reduction in peripherally inserted central catheter (PICC) use, (2) 25% reduction in sedations per patient, and (3) 50% reduction in empirical vancomycin administration.

METHODS

We implemented 4 prospective QI interventions at our tertiary children's hospital: (1) provider education, (2) centralization of admission location, (3) coordination of radiology-orthopedic communication, and (4) implementation of an MSKI infection algorithm and order set. We included patients 6 months to 18 years of age with acute osteomyelitis, septic arthritis, or pyomyositis and excluded patients with complex chronic conditions or ICU admission. We used statistical process control charts to analyze outcomes over 2 general periods: baseline (January 2015-October 17, 2016) and implementation (October 18, 2016-April 2019).

RESULTS

In total, 224 patients were included. The mean age was 6.1 years, and there were no substantive demographic or clinical differences between baseline and implementation groups. There was an 81% relative reduction in PICC use (centerline shift 54%-11%; 95% confidence interval 70-92) and 33% relative reduction in sedations per patient (centerline shift 1.8-1.2; 95% confidence interval 21-46). Empirical vancomycin use did not change (centerline 20%).

CONCLUSIONS

Our multidisciplinary MSKI QI interventions were associated with a significant decrease in the use of PICCs and sedations per patient but not empirical vancomycin administration.

Economic Burden of Urinary Tract Infections From Antibiotic-Resistant Escherichia coli Among Hospitalized Adult Patients in Lebanon: A Prospective Cohort Study

OBJECTIVES

The rising incidence of urinary tract infections (UTIs) attributable to Escherichia coli resistant isolates is becoming a serious public health concern. Although global rates of infection vary considerably by region, the growing prevalence of this uropathogen has been associated with a high economic burden and health strain. This study aims: (1) to estimate the differences in clinical and economic outcomes between 2 groups of adult hospitalized patients with UTIs from E. coli resistant and susceptible bacteria and (2) to investigate drivers of this cost from a payer's perspective.

METHODS

A prospective multicenter cohort study was conducted in 10 hospitals in Lebanon. The cost analysis followed a bottom-up microcosting approach; a linear regression was constructed to evaluate the predictors of hospitalization costs and a Cox proportional hazards model was used to estimate the impact of resistance on length of stay (LOS) and in-hospital mortality.

RESULTS

Out of 467 inpatients, 250 cases were because of resistant E. coli isolates. Results showed that patients with resistant uropathogens had 29% higher mean total hospitalization costs ($3429 vs $2651; P = .004), and an extended median LOS (6 days vs 5 days; P = .020) compared with susceptible cohorts. The selection of resistant bacteria and the Charlson comorbidity index predicted higher total hospitalization costs and in-hospital mortality.

CONCLUSION

In an era of increased pressure for cost containment, this study showed the burden of treating UTIs resulting from resistant bacteria. The results can inform cost-effectiveness analyses that intend to evaluate the benefit of a national action plan aimed at decreasing the impact of antibiotic resistance.

Methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci co-colonization in patients: A meta-analysis

BACKGROUND

Co-colonization of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) may result in the transfer of drug-resistant genes. The aim of this meta-analysis was to estimate the pooled co-colonization prevalence of MRSA and VRE.

METHODS

We searched PubMed, Embase, and Web of Science databases. The co-colonization prevalence of MRSA and VRE was assessed by calculating the proportion and 95% confidence intervals (CI). The random-effects model was used to calculate the pooled prevalence.

RESULTS

Eleven eligible studies were included in this meta-analysis. The pooled co-colonization prevalence of MRSA and VRE in patients was 7% (95% CI, 5.0%-9.0%). The results of regression analysis showed that co-colonization prevalence of MRSA and VRE was related to study design, setting, screening sites, and detection methods. We found that male patients (odds ratio [OR], 1.58; 95% CI, 1.09-2.28), patients with comorbid conditions such as diabetes mellitus (OR, 1.37; 95% CI, 1.05-1.78), chronic obstructive pulmonary disease (OR, 1.88; 95% CI, 1.27-2.79), and use of indwelling devices (OR, 4.08; 95% CI, 2.21-7.53) were risk factors for co-colonization by MRSA and VRE.

CONCLUSIONS

The co-colonization prevalence of MRSA and VRE in the patients was common. Appropriate measures should be adopted to limit the horizontal transmission of MRSA and VRE to minimize the future potential for co-colonization and the transfer of resistance genes among these pathogens.

IL-17-producing γδ T cells protect against Clostridium difficile infection

Colitis caused by Clostridium difficile infection is a growing cause of human morbidity and mortality, especially after antibiotic use in health care settings. The natural immunity of newborn infants and protective host immune mediators against C. difficile infection are not fully understood, with data suggesting that inflammation can be either protective or pathogenic. Here, we show an essential role for IL-17A produced by γδ T cells in host defense against C. difficile infection. Fecal extracts from children with C. difficile infection showed increased IL-17A and T cell receptor γ chain expression, and IL-17 production by intestinal γδ T cells was efficiently induced after infection in mice. C. difficile-induced tissue inflammation and mortality were markedly increased in mice deficient in IL-17A or γδ T cells. Neonatal mice, with naturally expanded RORγt+ γδ T cells poised for IL-17 production were resistant to C. difficile infection, whereas elimination of γδ T cells or IL-17A each efficiently overturned neonatal resistance against infection. These results reveal an expanded role for IL-17-producing γδ T cells in neonatal host defense against infection and provide a mechanistic explanation for the clinically observed resistance of infants to C. difficile colitis.

Comparing the efficacy and safety of faecal microbiota transplantation with bezlotoxumab in reducing the risk of recurrent Clostridium difficile infections: a systematic review and Bayesian network meta-analysis of randomised controlled trials

OBJECTIVES

The risk of recurrent Clostridium difficile infections (RCDIs) is high when treated with standard antibiotics therapy (SAT) alone. It is suggested that the addition of faecal microbiota transplantation (FMT) or bezlotoxumab after SAT reduces the risk of RCDI. In the absence of head-to-head randomised controlled trials (RCTs), this review attempts to compare the efficacy and safety of bezlotoxumab with FMT in reducing the risk of RCDI in hospitalised patients.

DESIGN

A systematic review and Bayesian network meta-analysis.

DATA SOURCE

A comprehensive search from inception to 30 February 2019 was conducted in four databases (Medline/PubMed, Embase, Scopus, ClinicalTrials.gov).

ELIGIBILITY CRITERIA

RCTs reporting the resolution of diarrhoea associated with RCDI without relapse for at least 60 days after the end of treatments as the primary outcome.

DATA EXTRACTION AND SYNTHESIS

We extracted author, year of publication, study design and binomial data that represented the resolution of diarrhoea or adverse events of monoclonal antibodies and FMT infusion. Random-effects models were used for resolution rate of RCDI and adverse events. The Cochrane Risk of Bias tool was used to assess the quality of included RCTs.

RESULTS

Out of 1003 articles identified, seven RCTs involving 3043 patients contributed to the review. No difference was reported between single or multiple infusions of FMT and bezlotoxumab in resolving RCDI, (OR 1.53, 95% credible interval (CrI) 0.39 to 5.16) and (OR 2.86, 95% CrI 1.29 to 6.57), respectively. Patients treated with SAT alone or bezlotoxumab with SAT showed significantly lower rates of diarrhoea than FMT (OR 0, 95% CrI 0 to 0.09) and (OR 0, 95% CrI 0 to 0.19), respectively. There was no difference in terms of other adverse events.

CONCLUSIONS

This is the first network meta-analysis that has compared the recently Food and Drug Administration-approved monoclonal antibody bezlotoxumab with FMT for resolving RCDI. The quality of the included RCTs was variable. The findings of this study suggested no difference between single or multiple infusions of FMT and bezlotoxumab. However, FMT was associated with a higher rate of non-serious diarrhoea as opposed to SAT used alone or in combination with bezlotoxumab.

Trends in Incidence and Outcomes of Clostridium difficile Colitis in Hospitalized Patients of Febrile Neutropenia: A Nationwide Analysis

INTRODUCTION

Clostridium difficile infection (CDI) has been attracting attention lately as the most common hospital acquired infection. Patients with neutropenia because of malignancy seem to be at an increased risk for developing CDI. There is currently limited data that assesses the national burden and outcomes of CDI in Febrile Neutropenia (FN).

METHODS

We analyzed the National Inpatient Sample (NIS) database for all subjects with discharge diagnosis of FN with or without CDI (ICD-9 codes 288.00, 288.03,780.60, and 008.45) as primary or secondary diagnosis during the period from 2008 to 2014. All analyses were performed with SAS, version 9.4 (SAS Institute).

RESULTS

From 2008 to 2014 there were total 19422 discharges of FN patients with CDI. There was a rising incidence of CDI in patients with FN from 4.11% (in 2008) to 5.83% (in 2014). The In-hospital mortality showed a decreasing trend from 7.79% (in 2008) to 5.32% (in 2014), likely because of improvements in diagnostics and treatment. The overall mortality (6.37% vs. 4.61%), length of stay >5 days (76.45% vs. 50.98%), hospital charges >50,000 dollars (64.43% vs. 40.29%), colectomy and colostomy (0.35% vs. 0.15%), and discharge to skilled nursing facility (10.47% vs. 6.43%) was significantly more in FN patients with CDI versus without CDI over 7 years (2008 to 2014). Age above 65 years, Hispanic race, hematological malignancies, urban hospital settings, and sepsis were significant predictors of mortality in febrile neutropenia patients with CDI.

DISCUSSION

Despite the significant decrease in mortality, the incidence of CDI is rising in hospitalized FN patients with underlying hematological malignancies. Risk factor modification, with the best possible empiric antibiotic regimen is imperative for reducing mortality and health care costs in this cohort.

Burden of hospitalizations over time with invasive aspergillosis in the United States, 2004-2013

Background

Using aggregated data available on the interactive website from the Agency for Healthcare Research and Quality’s Healthcare Cost and Utilization Project Network (HCUPnet), we examined the annual volume of invasive aspergillosis (IA)-related hospitalizations in the US.

Methods

This was a population study. Age-adjusted volumes were derived through population incidence calculated using year-specific censal and intercensal US population estimates available from the US Census Bureau. We additionally examined IA as the principal diagnosis and its associated outcomes in patients with ICD-9-CM codes 117.3, 117.9 and 484.6.

Results

The age-adjusted number of annual hospitalizations with IA grew from 35,968 cases in 2004 to 51,870 in 2013, a 44.2% overall increase, 4.4% per annum. Regionally, the South contributed the plurality of the cases (40%), and the Northeast the fewest (17%). While IA as principal diagnosis dropped, from 14.4 to 9.3%, mortality rose from 10 to 12%. Despite mean hospital length of stay decreasing from 13.3 (standard error [SE] 0.07) to 11.5 (SE 0.6) days, the corresponding mean hospital charges rose from $71,164 (SE $5248) to $123,005 (SE $9738). The aggregate US inflation-adjusted hospital charges for IA principal diagnosis rose from $436,074,445 in 2004 to $592,358,369 in 2013.

Conclusions

Given the substantial volume and rate of growth in IA-related hospitalizations in the US between 2004 and 2013, an increase in mortality and high costs, IA may represent an attractive target for intensive preventive efforts.

Modeling Clostridium difficile in a hospital setting: control and admissions of colonized and symptomatic patients

BACKGROUND

Clostridium difficile (C. difficile) infection is an important cause of healthcare-associated diarrhea. Several factors such as admission of colonized patients, levels of serum antibodies in patients, and control strategies may involve in determining the prevalence and the persistence of C. difficile in a hospital unit.

METHODS

We develop mathematical models based on deterministic and stochastic frameworks to investigate the effects of control strategies for colonized and symptomatic patients and admissions of colonized and symptomatic patients on the prevalence and the persistence of C. difficile.

RESULTS

Our findings suggest that control strategies and admissions of colonized and symptomatic patients play important roles in determining the prevalence and the persistence of C. difficile. Improving control of C. difficile in colonized and symptomatic patients may generally help reduce the prevalence and the persistence of C. difficile. However, if admission rates of colonized and symptomatic patients are high, the prevalence of C. difficile may remain high in a patient population even though strict control policies are applied.

CONCLUSION

Control strategies and admissions of colonized and symptomatic patients are important determinants of the prevalence and the persistence of C. difficile.

Epidemiological and genomic characterization of community-acquired Clostridium difficile infections

BACKGROUND

Clostridium difficile infection (CDI) is a major cause of morbidity and mortality in North America and Europe. The aim of this study was to identify epidemiologically-confirmed cases of community-acquired (CA)-CDI in a large North American urban center and analyze isolates using multiple genetic and phenotypic methods.

METHODS

Seventy-eight patients testing positive for C. difficile from outpatient clinics were further investigated by telephone questionnaire. CA-CDI isolates were characterized by antibiotic susceptibility, pulsed-field gel electrophoresis and whole genome sequencing. CA-CDI was defined as testing positive greater than 12 weeks following discharge or no previous hospital admission in conjunction with positive toxin stool testing.

RESULTS

51.3% (40/78) of the patients in this study were found to have bona fide CA-CDI. The majority of patients were female (71.8% vs. 28.2%) with 50-59 years of age being most common (21.8%). Common co-morbidities included ulcerative colitis (1/40; 2.5%), Crohn's disease (3/40; 7.5%), celiac disease (2/40; 5.0%) and irritable bowel syndrome (8/40; 20.0%). However, of 40 patients with CA-CDI, 9 (29.0%) had been hospitalized between 3 and 6 months prior and 31 (77.5%) between 6 and 12 months prior. The hypervirulent North American Pulostype (NAP) 1-like (9/40; 22.5%) strain was the most commonly identified pulsotype. Whole genome sequencing of CA-CDI isolates confirmed that NAP 1-like pulsotypes are commonplace in CA-CDI. From a therapeutic perspective, there was universal susceptibility to metronidazole and vancomycin.

CONCLUSIONS

All CA-CDI cases had some history of hospitalization if the definition were modified to health care facility exposure in the last 12 months and is supported by the genomic analysis. This raises the possibility that even CA-CDI may have nosocomial origins.

Antibiotic Resistance Rates by Geographic Region Among Ocular Pathogens Collected During the ARMOR Surveillance Study

Introduction

The Antibiotic Resistance Monitoring in Ocular micRoorganisms (ARMOR) study is an ongoing nationwide surveillance program that surveys in vitro antibiotic resistance rates and trends among ocular bacterial pathogens. We report resistance rates by geographic region for isolates collected from 2009 through 2016.

Methods

Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Streptococcus pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa isolates from ocular infections were collected at clinical centers across the US and categorized by geographic region based on state. Minimum inhibitory concentrations (MICs) for various antibiotics were determined at a central laboratory, and isolates were classified as susceptible or resistant based on established breakpoints. Geographic differences in methicillin resistance among staphylococci were evaluated by χ² test with multiple comparisons, whereas geographic differences in mean percentage antibiotic resistance were evaluated by one-way analyses of variance and Tukey’s test.

Results

Overall, 4829 isolates (Midwest, 1886; West, 1167; Northeast, 1143; South, 633) were evaluated. Across all regions, azithromycin resistance was high among S. aureus (49.4–67.8%), CoNS (61.0–62.8%), and S. pneumoniae (22.3–48.7%), whereas fluoroquinolone resistance ranged from 26.1% to 47.8% among S. aureus and CoNS. Across all regions, all staphylococci were susceptible to vancomycin; besifloxacin MICs were similar to those of vancomycin. Geographic differences were observed for overall mean resistance among S. aureus, S. pneumoniae, and P. aeruginosa isolates (p ≤ 0.005); no regional differences were found among CoNS and H. influenzae isolates. Methicillin resistance in particular was higher among S. aureus isolates from the South and CoNS isolates from the Midwest (p ≤ 0.006).

Conclusion

This analysis of bacterial isolates from the ARMOR study demonstrated geographic variation in resistance rates among ocular isolates, with greater in vitro resistance apparent in the South and Midwest for some organisms. These data may inform clinicians in selecting appropriate treatment options for ocular infections.

Funding

Bausch & Lomb, Inc.

Validation of a Clinical Decision Rule to Identify Risk Factors Associated With Multidrug-Resistant Urinary Pathogens in the Emergency Department

BACKGROUND

Antimicrobial resistance remains a significant obstacle for clinicians when treating patients presenting to the emergency department (ED) with urinary tract infections.

OBJECTIVE

The goal of the proposed study was to validate a previously developed clinical decision rule identifying risk factors for multidrug-resistant (MDR) urinary pathogens.

METHODS

We conducted a validation study of a previously published clinical decision rule to identify patients with MDR urinary pathogens using a cohort from an urban academic center ED with annual census over 80 000. Using our previously identified clinical risk factors, we determined the sensitivity, specificity, positive likelihood ratio (+LR), and negative LR (-LR) to estimate measures of precision of our clinical decision rule in the validation cohort.

RESULTS

Factors associated with MDR urinary pathogen included sex, recent hospitalization, nursing home residency, and catheter placement. Using our previously defined threshold of greater than 1 risk factor, the adjusted model in the validation cohort identified that only nursing home residency was associated with positive MDR pathogen (adjusted odds ratio = 4.13; 95% CI = 1.95-8.77). The clinical decision rule in the validation cohort yielded a sensitivity of 56.4%, specificity of 66.3%, +LR of 1.7, and -LR of 0.7. Conclusion and Relevance: Our clinical decision rule to identify patients at risk for MDR urinary pathogens was unable to be validated in the setting of different antimicrobial resistance patterns. Future studies should evaluate an improved clinical decision rule identifying risk factors associated with MDR pathogens that performs well in varying patient populations.

Trends in Methicillin-Resistant Staphylococcus aureus Hospitalizations in the United States, 2010-2014

Data from the National Inpatient Sample show that the decrease in hospitalizations related to methicillin-resistant Staphylococcus aureus (MRSA) infections between 2010 and 2014 primarily reflected declines in skin and soft tissue infections. Hospitalizations related to invasive MRSA remained largely unchanged.

Safety and efficacy of encapsulated fecal microbiota transplantation for recurrent Clostridium difficile infection: a systematic review

BACKGROUND AND AIMS

Fecal microbial transplantation (FMT) has been shown to be effective for the treatment of recurrent clostridium difficile infection (CDI). The efficacy and safety of freeze-dried encapsulated FMT for the treatment of recurrent CDI is unclear. We performed a systematic review to evaluate and analyze the current evidence in this respect.

MATERIALS AND METHODS

A systematic literature search was performed using the PubMed, Embase, and Medline databases until December 2017 to identify all original studies that investigated the role of administration of encapsulated FMT in recurrent CDI. The study included patients of all ages. Two independent reviewers extracted data and assessed the quality of publications; a third investigator resolved any discrepancies.

RESULTS

A total of six studies, five case series and one randomized-controlled trial, were included in this review. Overall, 341 patients completed treatment with encapsulated FMT. Only three major adverse events were reported and no deaths occurred directly related to FMT. In all, 285 patients responded to the first treatment, with no recurrence during the specified follow-up period set to meet the primary endpoint. Forty-two patients underwent a second treatment, with resolution of symptoms in 28 patients. At least five patients were reported to undergo a third treatment, with resolution in three of them. Only one patient was reported to have received four treatments without long-term resolution of symptoms.

CONCLUSION

Low-quality to moderate-quality evidence showed that encapsulated FMT is safe and cost-effective for the treatment and prevention of recurrent CDI. Its efficacy is not inferior to FMT performed through the nonoral route. Randomized-controlled trials are necessary to compare its efficacy with oral antimicrobial drugs and also to evaluate the potential adverse effects associated with the treatment.

Role of intestinal Clostridium in pathogenesis and treatment of diarrhea

Clostridium is a group of facultative anaerobic bacteria in the intestinal tract and is closely related to many diseases. By producing toxins and gas, Clostridium difficile and Clostridium perfringens can induce diarrhea. Clostridium butyricum, Faecalibacterium prausnitzii and other probiotics, Clostridium toxin vaccine, antibiotics, fecal bacteria transplantation, and other means are the main methods which are clinically used to inhibit the proliferation of harmful Clostridium and restore the balance of intestinal flora. In this paper, we will review the role of intestinal Clostridium in the pathogenesis and treatment of diarrhea to promote the exploration of new therapeutic methods for diarrhea caused by intestinal Clostridium infection.

Antifungal Activity of SCY-078 and Standard Antifungal Agents against 178 Clinical Isolates of Resistant and Susceptible Candida Species

SCY-078 in vitro activity was determined for 178 isolates of resistant or susceptible Candida albicans, Candida dubliniensis, Candida glabrata, Candida krusei, Candida lusitaniae, and Candida parapsilosis, including 44 Candida isolates with known genotypic (FKS1 or FKS2 mutations), phenotypic, or clinical resistance to echinocandins. Results were compared to those for anidulafungin, caspofungin, micafungin, fluconazole, and voriconazole. SCY-078 was shown to have excellent activity against both wild-type isolates and echinocandin- and azole-resistant isolates of Candida species.

Colonization With Vancomycin-Resistant Enterococci and Risk for Bloodstream Infection Among Patients With Malignancy: A Systematic Review and Meta-Analysis

Background

Vancomycin-resistant enterococci (VRE) cause severe infections among patients with malignancy, and these infections are usually preceded by gastrointestinal colonization.

Methods

We searched the PubMed and EMBASE databases (up to May 26, 2016) to identify studies that reported data on VRE gastrointestinal colonization among patients with solid or hematologic malignancy.

Results

Thirty-four studies, reporting data on 8391 patients with malignancy, were included in our analysis. The pooled prevalence of VRE colonization in this population was 20% (95% confidence interval [CI], 14%–26%). Among patients with hematologic malignancy, 24% (95% CI, 16%–34%) were colonized with VRE, whereas no studies reported data solely on patients with solid malignancy. Patients with acute leukemia were at higher risk for VRE colonization (risk ratio [RR] = 1.95; 95% CI, 1.17–3.26). Vancomycin use or hospitalization within 3 months were associated with increased colonization risk (RR = 1.92, 95% CI = 1.06–3.45 and RR = 4.68, 95% CI = 1.66–13.21, respectively). Among the different geographic regions, VRE colonization rate was 21% in North America (95% CI, 13%–31%), 20% in Europe (95% CI, 9%–34%), 23% in Asia (95% CI, 13%–38%), and 4% in Oceania (95% CI, 2%–6%). More importantly, colonized patients were 24.15 (95% CI, 10.27–56.79) times more likely to develop a bloodstream infection due to VRE than noncolonized patients.

Conclusions

A substantial VRE colonization burden exists among patients with malignancy, and colonization greatly increases the risk for subsequent VRE bloodstream infection. Adherence to antimicrobial stewardship is needed, and a re-evaluation of the use of vancomycin as empiric therapy in this patient population may be warranted.

Incidence and Outcomes Associated With Infections Caused by Vancomycin-Resistant Enterococci in the United States: Systematic Literature Review and Meta-Analysis

BACKGROUND

Information about the health and economic impact of infections caused by vancomycin-resistant enterococci (VRE) can inform investments in infection prevention and development of novel therapeutics.

OBJECTIVE

To systematically review the incidence of VRE infection in the United States and the clinical and economic outcomes.

METHODS

We searched various databases for US studies published from January 1, 2000, through June 8, 2015, that evaluated incidence, mortality, length of stay, discharge to a long-term care facility, readmission, recurrence, or costs attributable to VRE infections. We included multicenter studies that evaluated incidence and single-center and multicenter studies that evaluated outcomes. We kept studies that did not have a denominator or uninfected controls only if they assessed postinfection length of stay, costs, or recurrence. We performed meta-analysis to pool the mortality data.

RESULTS

Five studies provided incidence data and 13 studies evaluated outcomes or costs. The incidence of VRE infections increased in Atlanta and Detroit but did not increase in national samples. Compared with uninfected controls, VRE infection was associated with increased mortality (pooled odds ratio, 2.55), longer length of stay (3-4.6 days longer or 1.4 times longer), increased risk of discharge to a long-term care facility (2.8- to 6.5-fold) or readmission (2.9-fold), and higher costs ($9,949 higher or 1.6-fold more).

CONCLUSIONS

VRE infection is associated with large attributable burdens, including excess mortality, prolonged in-hospital stay, and increased treatment costs. Multicenter studies that use suitable controls and adjust for time at risk or confounders are needed to estimate the burden of VRE infections.

Infect Control Hosp Epidemiol. 2017;38:203–215

Ursodeoxycholic Acid Inhibits Clostridium difficile Spore Germination and Vegetative Growth, and Prevents the Recurrence of Ileal Pouchitis Associated With the Infection

GOALS

To test whether ursodeoxycholic acid (UDCA) is inhibitory to Clostridium difficile and can be used in the treatment of C. difficile-associated ileal pouchitis.

BACKGROUND

The restoration of secondary bile metabolism may be the key mechanism for fecal microbiota transplantation (FMT) in treating recurrent C. difficile infections (RCDI). Therefore, it is possible that exogenous administration of inhibitory bile acids may be used directly as nonantibiotic therapeutics for this indication. The need for such a treatment alternative is especially significant in patients with refractory C. difficile-associated pouchitis, where the efficacy of FMT may be limited.

STUDY

We measured the ability of UDCA to suppress the germination and the vegetative growth of 11 clinical isolate strains of C. difficile from patients treated with FMT for RCDI. In addition, we used oral UDCA to treat a patient with RCDI pouchitis that proved refractory to multiple antibiotic treatments and FMT.

RESULTS

UDCA was found to be inhibitory to the germination and the vegetative growth of all C. difficile strains tested. Fecal concentrations of UDCA from the patient with RCDI pouchitis exceeded levels necessary to inhibit the germination and the growth of C. difficile in vitro. The patient has remained infection free for over 10 months after the initiation of UDCA.

CONCLUSIONS

UDCA can be considered as a therapeutic option in patients with C. difficile-associated pouchitis. Further studies need to be conducted to define the optimal dose and duration of such a treatment. In addition, bile acid derivatives inhibitory to C. difficile that are able to achieve high intracolonic concentrations may be developed as therapeutics for RCDI colitis.

Synthetic Lipoteichoic Acid Glycans Are Potential Vaccine Candidates to Protect from Clostridium difficile Infections

Infections with Clostridium difficile increasingly cause morbidity and mortality worldwide. Bacterial surface glycans including lipoteichoic acid (LTA) were identified as auspicious vaccine antigens to prevent colonization. Here, we report on the potential of synthetic LTA glycans as vaccine candidates. We identified LTA-specific antibodies in the blood of C. difficile patients. Therefore, we evaluated the immunogenicity of a semi-synthetic LTA-CRM₁₉₇ glycoconjugate. The conjugate elicited LTA-specific antibodies in mice that recognized natural LTA epitopes on the surface of C. difficile bacteria and inhibited intestinal colonization of C. difficile in mice in vivo. Our findings underscore the promise of synthetic LTA glycans as C. difficile vaccine candidates.

Rising Vancomycin-Resistant Enterococcus Infections in Hospitalized Children in the United States

OBJECTIVE

Vancomycin-resistant Enterococcus (VRE) is an emerging drug-resistant organism responsible for increasing numbers of nosocomial infections in adults. Few data are available on the epidemiology and impact of VRE infections in children. We hypothesized a significant increase in VRE infections among hospitalized children. Additionally, we predicted that VRE infection would be associated with certain comorbid conditions and increased duration and cost of hospitalization.

METHODS

A retrospective study of inpatient pediatric patients was performed using data on hospitalizations for VRE from the Healthcare Cost and Utilization Project Kids' Inpatient Database from 1997 to 2012. We used a multivariable logistic regression model to establish factors associated with VRE infection and a high-dimensional propensity score match to evaluate death, length of stay, and cost of hospitalization.

RESULTS

Hospitalizations for VRE infection showed an increasing trend, from 53 hospitalizations per million in 1997 to 120 in 2012 (P < .001). Conditions associated with VRE included Clostridium difficile infection and other diagnoses involving immunosuppression and significant antibiotic and health care exposure. Patients with VRE infection had a significantly longer length of stay (attributable difference [AD] 2.1 days, P < .001) and higher hospitalization costs (AD $8233, P = .004). VRE infection was not associated with an increased risk of death (odds ratio 1.03; 95% confidence interval 0.73-1.47).

CONCLUSIONS

VRE infections among hospitalized children are increasing at a substantial rate. This study demonstrates the significant impact of VRE on the health of pediatric patients and highlights the importance of strict adherence to existing infection control policies and VRE surveillance in certain high-risk pediatric populations.

Comparative Evaluation of the BD Phoenix Yeast ID Panel and Remel RapID Yeast Plus System for Yeast Identification

Becton Dickinson Phoenix Yeast ID Panel was compared to the Remel RapID Yeast Plus System using 150 recent clinical yeast isolates and the API 20C AUX system to resolve discrepant results. The concordance rate between the Yeast ID Panel and the RapID Yeast Plus System (without arbitration) was 93.3% with 97.3% (146/150) and 95.3% (143/150) of the isolates correctly identified by the Becton Dickinson Phoenix and the Remel RapID, respectively, with arbitration.

Evaluating state-specific antibiotic resistance measures derived from central line-associated bloodstream infections, national healthcare safety network, 2011

DISCLOSURE The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention or the Agency for Toxic Substances and Diseases Registry. OBJECTIVE Describe the impact of standardizing state-specific summary measures of antibiotic resistance that inform regional interventions to reduce transmission of resistant pathogens in healthcare settings. DESIGN Analysis of public health surveillance data. METHODS Central line-associated bloodstream infection (CLABSI) data from intensive care units (ICUs) of facilities reporting to the National Healthcare Safety Network in 2011 were analyzed. For CLABSI due to methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum cephalosporin (ESC)-nonsusceptible Klebsiella species, and carbapenem-nonsusceptible Klebsiella species, we computed 3 state-level summary measures of nonsusceptibility: crude percent nonsusceptible, model-based adjusted percent nonsusceptible, and crude infection incidence rate. RESULTS Overall, 1,791 facilities reported CLABSIs from ICU patients. Of 1,618 S. aureus CLABSIs with methicillin-susceptibility test results, 791 (48.9%) were due to MRSA. Of 756 Klebsiella CLABSIs with ESC-susceptibility test results, 209 (27.7%) were due to ESC-nonsusceptible Klebsiella, and among 661 Klebsiella CLABSI with carbapenem susceptibility test results, 70 (10.6%) were due to carbapenem-nonsusceptible Klebsiella. All 3 state-specific measures demonstrated variability in magnitude by state. Adjusted measures, with few exceptions, were not appreciably different from crude values for any phenotypes. When linking values of crude and adjusted percent nonsusceptible by state, a state's absolute rank shifted slightly for MRSA in 5 instances and only once each for ESC-nonsusceptible and carbapenem-nonsusceptible Klebsiella species. Infection incidence measures correlated strongly with both percent nonsusceptibility measures. CONCLUSIONS Crude state-level summary measures, based on existing NHSN CLABSI data, may suffice to assess geographic variability in antibiotic resistance. As additional variables related to antibiotic resistance become available, risk-adjusted summary measures are preferable.

Trends in Antibiotic Use and Nosocomial Pathogens in Hospitalized Veterans With Pneumonia at 128 Medical Centers, 2006-2010

BACKGROUND

In 2005, pneumonia practice guidelines recommended broad-spectrum antibiotics for patients with risk factors for nosocomial pathogens. The impact of these recommendations on the ability of providers to match treatment with nosocomial pathogens is unknown.

METHODS

Among hospitalizations with a principal diagnosis of pneumonia at 128 Department of Veterans Affairs medical centers from 2006 through 2010, we measured annual trends in antibiotic selection; initial blood or respiratory cultures positive for methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Acinetobacter species; and alignment between antibiotic coverage and culture results for MRSA and P. aeruginosa, calculating sensitivity, specificity, and diagnostic odds ratio using a 2 × 2 contingency table.

RESULTS

In 95 511 hospitalizations for pneumonia, initial use of vancomycin increased from 16% in 2006 to 31% in 2010, and piperacillin-tazobactam increased from 16% to 27%, and there was a decrease in both ceftriaxone (from 39% to 33%) and azithromycin (change from 39% to 36%) (P < .001 for all). The proportion of hospitalizations with cultures positive for MRSA decreased (from 2.5% to 2.0%; P < .001); no change was seen for P. aeruginosa (1.9% to 2.0%; P = .14) or Acinetobacter spp. (0.2% to 0.2%; P = .17). For both MRSA and P. aeruginosa, sensitivity increased (from 46% to 65% and 54% to 63%, respectively; P < .001) and specificity decreased (from 85% to 69% and 76% to 68%; P < .001), with no significant changes in diagnostic odds ratio (decreases from 4.6 to 4.1 [P = .57] and 3.7 to 3.2 [P = .95], respectively).

CONCLUSIONS

Between 2006 and 2010, we found a substantial increase in the use of broad-spectrum antibiotics for pneumonia despite no increase in nosocomial pathogens. The ability of providers to accurately match antibiotic coverage to nosocomial pathogens remains low.

Shifting trends in the incidence of Pseudomonas aeruginosa septicemia in hospitalized adults in the United States from 1996-2010

BACKGROUND

Pseudomonas aeruginosa septicemia (PAS) is associated with high mortality rates and substantial resource utilization; however, the burden of PAS in the United States in recent years is unknown.

METHODS

This was a retrospective analysis of the U.S. National Hospital Discharge Surveys from 1996-2010. Adult patients with an ICD-9-CM code for PAS (038.43) were included. Incidence, in-hospital mortality, and hospital length of stay (LOS) for PAS discharges were reported. Incidence was calculated as PAS discharges per 10,000 total adult discharges.

RESULTS

Overall, 213,553 patients had a PAS discharge diagnosis during the study period. Patients had a median (interquartile range [IQR]) age of 69 (55-78) years and were predominately men (61%) and white (75%). PAS incidence declined from 6.5 per 10,000 in 1996 to 3.1 per 10,000 in 2001 and then increased to 6.5 per 10,000 in 2010. PAS incidence was highest in the Northeast (7.6 per 10,000) and lowest in the South (6.2 per 10,000). The overall mortality rate was 16%, but this ranged from 10%-26% over the study period. Median LOS was 10 (IQR, 6-19) days, and this varied over the study period (8-13 days).

CONCLUSIONS

The incidence of PAS has increased among hospitalized adults in the United States since 2001, with little evidence of improvement in mortality or LOS.

Regional and seasonal variation in Clostridium difficile infections among hospitalized patients in the United States, 2001-2010

BACKGROUND

This study identified national regional and seasonal variations in Clostridium difficile infection (CDI) incidence and mortality among hospitalized patients in the United States over a 10-year period.

METHODS

This was a retrospective cohort study of the U.S. National Hospital Discharge Survey from 2001-2010. Eligible cases had an ICD-9-CM discharge diagnosis code for CDI (008.45). Data weights were used to derive national estimates. CDI incidence and mortality were presented descriptively. Regions were as defined by the U.S. Census Bureau. Seasons included the following: winter (December-February), spring (March-May), summer (June-August), and fall (September-November).

RESULTS

These data represent 2.3 million CDI discharges. Overall, CDI incidence was highest in the Northeast (8.0 CDIs/1,000 discharges) and spring (6.2 CDIs/1,000 discharges). CDI incidence was lowest in the West (4.8 CDIs/1,000 discharges) and fall (5.6 CDIs/1,000 discharges). Peak CDI incidence among children occurred in the West (1.7 CDI/1,000 discharges) and winter (1.5 CDI/1,000 discharges). Mortality among all CDI patients was highest in the Midwest (7.3%) and during the winter (7.9%).

CONCLUSION

The region and season with the highest CDI incidence rates among patients hospitalized in U.S. hospitals were the Northeast and spring, respectively. The highest CDI mortality rates were seen in the Midwest and winter. Children exhibited different regional and seasonal CDI variations compared with adults and older adults.

Strategies to prevent Clostridium difficile infections in acute care hospitals: 2014 update

Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their Clostridium difficile infection (CDI) prevention efforts. This document updates “Strategies to Prevent Clostridium difficile Infections in Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.

Pediatric vancomycin dosing: Trends over time and the impact of therapeutic drug monitoring

Monitoring of vancomycin trough concentrations is recommended for pediatric patients in the product label and by several professional societies. However, among a network of freestanding children's hospitals vancomycin therapeutic drug monitoring (TDM) practices were reported to be highly variable. In this study, we sought to evaluate whether trends in vancomycin use and TDM changed across a large healthcare delivery system in Utah and Idaho from 2006 to 2012. Children ≤18 years who received ≥2 vancomycin doses were included. Overall, vancomycin TDM was performed during 5,035 (80%) of 6,259 hospital encounters, in which 85,442 doses were administered and 7,935 concentrations were obtained. Across this time period, the median trough concentration increased from 10.9 to 13.7 µg/mL (P < .001), which temporally coincided with recommendations published by the Infectious Disease Society of America that recommend targeting higher trough concentrations. Two or more abnormally low trough concentrations were accompanied by an increase in the dose 75% of the time. Similarly, ≥2 abnormally high trough concentrations were followed by a decrease in the dose 35% of the time. In aggregate, these data suggest that vancomycin TDM is commonly performed among children and the majority of abnormal trough concentrations were associated with an appropriate modification to the dosing regimen.

Regional data analysis of Candida non-albicans strains collected in United States medical sites over a 6-year period, 2006-2011

Limited data are available on temporal and geographic variation of occurrence and antifungal resistance of non-C. albicans Candida species (non-CA-CSP) from the USA. The objective of this study was to evaluate the occurrence and antifungal resistance of 1694 isolates of non-CA-CSP collected during the period 2006-2011. Isolates were recovered in 33 hospitals located in four regions: Northcentral, North-east, South-east and West and tested using CLSI reference broth microdilution methods. Non-CA-CSP represented 55.6% of all Candida. C. glabrata was most predominant (39-42% of non-CA-CSP). Infections due to C. glabrata, C. krusei and C. dubliniensis increased over the 6 years. Anidulafungin (3.6%) and caspofungin (5.7%) resistance were prominent among C. glabrata from the North-east and West regions respectively. Resistance to micafungin was detected in 2.0% and 2.9% of C. glabrata from the West and North-east regions respectively. Echinocandin resistance was low, except for C. dubliniensis. Azole resistance was most prominent among C. glabrata from the South-east (13.6% fluconazole R) and the West (18.0%). Cross-resistance among three tested azoles was observed in C. glabrata from all regions. Whereas differences in species distribution and antifungal R varied across geographic regions, there was little evidence of temporal increase in resistance to azoles or echinocandins in the monitored non-CA-CSP.

Epidemiology of Clostridium difficile infection

There has been dramatic change in the epidemiology of Clostridium difficile infection (CDI) since the turn of the 21st century noted by a marked increase in incidence and severity, occurring at a disproportionately higher frequency in older patients. Historically considered a nosocomial infection associated with antibiotic exposure, CDI has now also emerged in the community in populations previously considered low risk. Emerging risk factors and disease recurrence represent continued challenges in the management of CDI. The increased incidence and severity associated with CDI has coincided with the emergence and rapid spread of a previously rare strain, ribotype 027. Recent data from the United States and Europe suggest that the incidence of CDI may have reached a crescendo in the recent years and is perhaps beginning to plateau. The acute care direct costs of CDI were estimated to be US$4.8 billion in 2008. However, nearly all the published studies have focused on CDI diagnosed and treated in the acute care hospital setting and fail to measure the burden outside the hospital, including recently discharged patients, outpatients, and those in long-term care facilities. Enhanced surveillance methods are needed to monitor the incidence, to identify populations at risk, and to characterize the molecular epidemiology of strains causing CDI.

Natural history of colonization with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE): a systematic review

Background

No published systematic reviews have assessed the natural history of colonization with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE). Time to clearance of colonization has important implications for patient care and infection control policy.

Methods

We performed parallel searches in OVID Medline for studies that reported the time to documented clearance of MRSA and VRE colonization in the absence of treatment, published between January 1990 and July 2012.

Results

For MRSA, we screened 982 articles, identified 16 eligible studies (13 observational studies and 3 randomized controlled trials), for a total of 1,804 non-duplicated subjects. For VRE, we screened 284 articles, identified 13 eligible studies (12 observational studies and 1 randomized controlled trial), for a total of 1,936 non-duplicated subjects. Studies reported varying definitions of clearance of colonization; no study reported time of initial colonization. Studies varied in the frequency of sampling, assays used for sampling, and follow-up period. The median duration of total follow-up was 38 weeks for MRSA and 25 weeks for VRE. Based on pooled analyses, the model-estimated median time to clearance was 88 weeks after documented colonization for MRSA-colonized patients and 26 weeks for VRE-colonized patients. In a secondary analysis, clearance rates for MRSA and VRE were compared by restricting the duration of follow-up for the MRSA studies to the maximum observed time point for VRE studies (43 weeks). With this restriction, the model-fitted median time to documented clearance for MRSA would occur at 41 weeks after documented colonization, demonstrating the sensitivity of the pooled estimate to length of study follow-up.

Conclusions

Few available studies report the natural history of MRSA and VRE colonization. Lack of a consistent definition of clearance, uncertainty regarding the time of initial colonization, variation in frequency of sampling for persistent colonization, assays employed and variation in duration of follow-up are limitations of the existing published literature. The heterogeneity of study characteristics limits interpretation of pooled estimates of time to clearance, however, studies included in this review suggest an increase in documented clearance over time, a result which is sensitive to duration of follow-up.

Community-acquired Clostridium difficile infection: an increasing public health threat

There has been a startling shift in the epidemiology of Clostridium difficile infection over the last decade worldwide, and it is now increasingly recognized as a cause of diarrhea in the community. Classically considered a hospital-acquired infection, it has now emerged in populations previously considered to be low-risk and lacking the traditional risk factors for C. difficile infection, such as increased age, hospitalization, and antibiotic exposure. Recent studies have demonstrated great genetic diversity for C. difficile, pointing toward diverse sources and a fluid genome. Environmental sources like food, water, and animals may play an important role in these infections, apart from the role symptomatic patients and asymptomatic carriers play in spore dispersal. Prospective strain typing using highly discriminatory techniques is a possible way to explore the suspected diverse sources of C. difficile infection in the community. Patients with community-acquired C. difficile infection do not necessarily have a good outcome and clinicians should be aware of factors that predict worse outcomes in order to prevent them. This article summarizes the emerging epidemiology, risk factors, and outcomes for community-acquired C. difficile infection.

Epidemiology of Clostridium difficile infection

There has been dramatic change in the epidemiology of Clostridium difficile infection (CDI) since the turn of the 21st century noted by a marked increase in incidence and severity, occurring at a disproportionately higher frequency in older patients. Historically considered a nosocomial infection associated with antibiotic exposure, CDI has now also emerged in the community in populations previously considered low risk. Emerging risk factors and disease recurrence represent continued challenges in the management of CDI. The increased incidence and severity associated with CDI has coincided with the emergence and rapid spread of a previously rare strain, ribotype 027. Recent data from the United States and Europe suggest that the incidence of CDI may have reached a crescendo in the recent years and is perhaps beginning to plateau. The acute care direct costs of CDI were estimated to be US$4.8 billion in 2008. However, nearly all the published studies have focused on CDI diagnosed and treated in the acute care hospital setting and fail to measure the burden outside the hospital, including recently discharged patients, outpatients, and those in long-term care facilities. Enhanced surveillance methods are needed to monitor the incidence, to identify populations at risk, and to characterize the molecular epidemiology of strains causing CDI.

Increasing burden of methicillin-resistant Staphylococcus aureus hospitalizations at US academic medical centers, 2003-2008

OBJECTIVE

The incidence of invasive methicillin-resistant Staphylococcus aureus (MRSA) infections in the United States decreased during 2005-2008, but noninvasive community-associated MRSA (CA-MRSA) infections also frequently lead to hospitalization. We estimated the incidence of all MRSA infections among inpatients at US academic medical centers (AMCs) per 1,000 admissions during 2003-2008.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Hospitalized patients at 90% of nonprofit US AMCs during 2003-2008.

METHODS

Administrative data on MRSA infections from a hospital discharge database (University HealthSystem Consortium [UHC]) were adjusted for underreporting of the MRSA V09.0 International Classification of Diseases, Ninth Revision, Clinical Modification code and validated using chart reviews for patients with known MRSA infections in 2004-2005, 2006, and 2007.

RESULTS

The mean sensitivity of administrative data for MRSA infections at the University of Chicago Medical Center in three 12-month periods during 2004-2007 was 59.1%. On the basis of estimates of billing data sensitivity from the literature and the University of Chicago Medical Center, the number of MRSA infections per 1,000 hospital discharges at US AMCs increased from 20.9 (range, 11.1-47.7) in 2003 to 41.7 (range, 21.9-94.0) in 2008. At the University of Chicago Medical Center, among infections cultured more than 3 days prior to hospital discharge, CA-MRSA infections were more likely to be captured in the UHC billing-derived data than were healthcare-associated MRSA infections.

CONCLUSIONS

The number of hospital admissions for any MRSA infection per 1,000 hospital admissions overall increased during 2003-2008. Use of unadjusted administrative hospital discharge data or surveillance for invasive disease far underestimates the number of MRSA infections among hospitalized patients.

Clostridium difficile infection: the scope of the problem

Clostridium difficile infection (CDI) is increasingly common, and it is associated with significant morbidity, mortality, and cost burden for patients and the healthcare system. The severity and rates of recurrent CDI and associated mortality are also increasing. This article is an overview of the changes in CDI epidemiology that have occurred since the turn of the century and the current scope of the problem. The 3 articles that follow in this supplement address the diagnosis and treatment of initial and recurrent CDI, and current practice guidelines for the prevention and control of CDI in the hospital setting.

Ventilator-associated pneumonia due to meticillin-resistant Staphylococcus aureus: risk factors and outcome in a large general hospital

BACKGROUND

Data about risk factors and impact on outcome of methicillin-resistant S. aureus (MRSA) in unselected patients with ventilator-associated pneumonia (VAP) are limited.

AIM

To assess predisposing factors and outcome of VAP due to MRSA in a large teaching institution.

METHODS

Prospective study carried out over four years in the three adult ICUs of our hospital. Patients with MRSA-VAP were compared with those with bacterial VAP due to other microorganisms.

FINDINGS

Overall, 474 episodes of bacterial VAP were collected. Significant differences between MRSA-VAP (111) and VAP due to other microorganisms (363) were found for median age (68 vs. 62 years), median APACHE II score (12 vs. 11), neurosurgery (5.4% vs. 13.8%), abdominal surgery (35% vs. 19%), prior treatment with any antibiotic (82.9% vs. 64.5%) and with imipenem (24% vs. 11%) at present admission before VAP, and pleural effusion (12% vs. 5%). Multivariate analysis adjusted for confounding factors showed that higher APACHE II score, prior treatment with any antibiotic and pleural effusion were independent risk factors for MRSA. As for treatment and outcome, the differences between MRSA-VAP and other VAP were inadequate empiric treatment (70% vs. 53%), median cost of antibiotics per episode (€974 vs. €726), and in-hospital mortality (60% vs. 47%). At multivariate analysis, however, MRSA was not found to be an independent risk factor for mortality.

CONCLUSION

MRSA is a common cause of VAP. Underlying conditions predispose to its high mortality.

Pathology consultation on detection of Clostridium difficile

Laboratory methods for detecting Clostridium difficile have undergone considerable evolution since the organism's etiologic association with antibiotic-associated diarrhea and colitis was established. Clearly, familiarity with the advantages and shortcomings of the various assays is essential for the laboratory director when choosing among these tests. For the consulting pathologist, furthermore, an understanding of the laboratory's role in securing a diagnosis of C difficile infection (CDI) is also required to identify requests for unnecessary testing that may be costly and potentially misleading. The purpose of this article is to highlight the major differences in laboratory test methods for CDI and to review a few commonly encountered provider ordering scenarios.

Body mass index and outcomes from pancreatic resection: a review and meta-analysis

INTRODUCTION

There are 1.6 billion adults worldwide who are overweight, with body mass indices (BMI) between 25 and 30, while more than 400 million are obese (BMI >30). Obesity predicts the incidence of and poor outcomes from pancreatic cancer. Obesity has also been linked to surgical complications in pancreatectomy, including increased length of hospital stay, surgical infections, blood loss, and decreased survival. However, BMI's impact on many complications following pancreatectomy remains controversial.

METHODS

We performed a MEDLINE search of all combinations of "BMI" with "pancreatectomy," "pancreatoduodenectomy," or "pancreaticoduodenectomy." From included studies, we created pooled and weighted estimates for quantitative and qualitative outcomes. We used the PRISMA criteria to ensure this project's validity.

RESULTS

Our primary cohort included 2,736 patients with BMI <30, 1,682 with BMI >25, and 546 with BMI between 25 and 30. Most outcomes showed no definitive differences across BMIs. Pancreatic fistula (PF) rates ranged from 4.7% to 31.0%, and four studies found multivariate association between BMI and PF (range odds ratio 1.6-4.2). Pooled analyses of PF by BMI showed significant association (p < 0.05).

CONCLUSION

BMI increases the operative complexity of pancreatectomy. However, with aggressive peri- and post-operative care, increases in BMI-associated morbidity and mortality may be mitigated.

Validity of ICD-9-CM coding for identifying incident methicillin-resistant Staphylococcus aureus (MRSA) infections: is MRSA infection coded as a chronic disease?

BACKGROUND AND OBJECTIVE

Investigators and medical decision makers frequently rely on administrative databases to assess methicillin-resistant Staphylococcus aureus (MRSA) infection rates and outcomes. The validity of this approach remains unclear. We sought to assess the validity of the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code for infection with drug-resistant microorganisms (V09) for identifying culture-proven MRSA infection.

DESIGN

Retrospective cohort study.

METHODS

All adults admitted to 3 geographically distinct hospitals between January 1, 2001, and December 31, 2007, were assessed for presence of incident MRSA infection, defined as an MRSA-positive clinical culture obtained during the index hospitalization, and presence of the V09 ICD-9-CM code. The κ statistic was calculated to measure the agreement between presence of MRSA infection and assignment of the V09 code. Sensitivities, specificities, positive predictive values, and negative predictive values were calculated.

RESULTS

There were 466,819 patients discharged during the study period. Of the 4,506 discharged patients (1.0%) who had the V09 code assigned, 31% had an incident MRSA infection, 20% had prior history of MRSA colonization or infection but did not have an incident MRSA infection, and 49% had no record of MRSA infection during the index hospitalization or the previous hospitalization. The V09 code identified MRSA infection with a sensitivity of 24% (range, 21%-34%) and positive predictive value of 31% (range, 22%-53%). The agreement between assignment of the V09 code and presence of MRSA infection had a κ coefficient of 0.26 (95% confidence interval, 0.25-0.27).

CONCLUSIONS

In its current state, the ICD-9-CM code V09 is not an accurate predictor of MRSA infection and should not be used to measure rates of MRSA infection.