Which comorbid conditions should we be analyzing as risk factors for healthcare-associated infections?

OBJECTIVETo determine which comorbid conditions are considered causally related to central-line associated bloodstream infection (CLABSI) and surgical-site infection (SSI) based on expert consensus.DESIGNUsing the Delphi method, we administered an iterative, 2-round survey to 9 infectious disease and infection control experts from the United States.METHODSBased on our selection of components from the Charlson and Elixhauser comorbidity indices, 35 different comorbid conditions were rated from 1 (not at all related) to 5 (strongly related) by each expert separately for CLABSI and SSI, based on perceived relatedness to the outcome. To assign expert consensus on causal relatedness for each comorbid condition, all 3 of the following criteria had to be met at the end of the second round: (1) a majority (&gt;50%) of experts rating the condition at 3 (somewhat related) or higher, (2) interquartile range (IQR)≤1, and (3) standard deviation (SD)≤1.RESULTSFrom round 1 to round 2, the IQR and SD, respectively, decreased for ratings of 21 of 35 (60%) and 33 of 35 (94%) comorbid conditions for CLABSI, and for 17 of 35 (49%) and 32 of 35 (91%) comorbid conditions for SSI, suggesting improvement in consensus among this group of experts. At the end of round 2, 13 of 35 (37%) and 17 of 35 (49%) comorbid conditions were perceived as causally related to CLABSI and SSI, respectively.CONCLUSIONSOur results have produced a list of comorbid conditions that should be analyzed as risk factors for and further explored for risk adjustment of CLABSI and SSI.Infect Control Hosp Epidemiol 2017;38:449–454</jats:sec

The effect of adding comorbidities to current centers for disease control and prevention central-line–associated bloodstream infection risk-adjustment methodology

BACKGROUNDRisk adjustment is needed to fairly compare central-line–associated bloodstream infection (CLABSI) rates between hospitals. Until 2017, the Centers for Disease Control and Prevention (CDC) methodology adjusted CLABSI rates only by type of intensive care unit (ICU). The 2017 CDC models also adjust for hospital size and medical school affiliation. We hypothesized that risk adjustment would be improved by including patient demographics and comorbidities from electronically available hospital discharge codes.METHODSUsing a cohort design across 22 hospitals, we analyzed data from ICU patients admitted between January 2012 and December 2013. Demographics and International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) discharge codes were obtained for each patient, and CLABSIs were identified by trained infection preventionists. Models adjusting only for ICU type and for ICU type plus patient case mix were built and compared using discrimination and standardized infection ratio (SIR). Hospitals were ranked by SIR for each model to examine and compare the changes in rank.RESULTSOverall, 85,849 ICU patients were analyzed and 162 (0.2%) developed CLABSI. The significant variables added to the ICU model were coagulopathy, paralysis, renal failure, malnutrition, and age. The C statistics were 0.55 (95% CI, 0.51–0.59) for the ICU-type model and 0.64 (95% CI, 0.60–0.69) for the ICU-type plus patient case-mix model. When the hospitals were ranked by adjusted SIRs, 10 hospitals (45%) changed rank when comorbidity was added to the ICU-type model.CONCLUSIONSOur risk-adjustment model for CLABSI using electronically available comorbidities demonstrated better discrimination than did the CDC model. The CDC should strongly consider comorbidity-based risk adjustment to more accurately compare CLABSI rates across hospitals.Infect Control Hosp Epidemiol 2017;38:1019–1024</jats:sec

Treatment Options for Carbapenem-Resistant Enterobacteriaceae Infections

This article provides a comprehensive review of currently available treatment options for infections due to carbapenem-resistant Enterobacteriaceae (CRE). Antimicrobial resistance in Gram-negative bacteria is an emerging and serious global public health threat. Carbapenems have been used as the “last-line” treatment for infections caused by resistant Enterobacteriaceae, including those producing extended spectrum ß-lactamases. However, Enterobacteriaceae that produce carbapenemases, which are enzymes that deactivate carbapenems and most other ß-lactam antibiotics, have emerged and are increasingly being reported worldwide. Despite this increasing burden, the most optimal treatment for CRE infections is largely unknown. For the few remaining available treatment options, there are limited efficacy data to support their role in therapy. Nevertheless, current treatment options include the use of older agents, such as polymyxins, fosfomycin, and aminoglycosides, which have been rarely used due to efficacy and/or toxicity concerns. Optimization of dosing regimens and combination therapy are additional treatment strategies being explored. Carbapenem-resistant Enterobacteriaceae infections are associated with poor outcomes and high mortality. Continued research is critically needed to determine the most appropriate treatment

The impact of obesity and timely antiviral administration on severe influenza outcomes among hospitalized adults

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141541/1/jmv24946.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141541/2/jmv24946_am.pd

Clinical and Financial Outcomes Due to Methicillin Resistant Staphylococcus aureus Surgical Site Infection: A Multi-Center Matched Outcomes Study

The clinical and financial outcomes of SSIs directly attributable to MRSA and methicillin-resistance are largely uncharacterized. Previously published data have provided conflicting conclusions.We conducted a multi-center matched outcomes study of 659 surgical patients. Patients with SSI due to MRSA were compared with two groups: matched uninfected control patients and patients with SSI due to MSSA. Four outcomes were analyzed for the 90-day period following diagnosis of the SSI: mortality, readmission, duration of hospitalization, and hospital charges. Attributable outcomes were determined by logistic and linear regression.In total, 150 patients with SSI due to MRSA were compared to 231 uninfected controls and 128 patients with SSI due to MSSA. SSI due to MRSA was independently predictive of readmission within 90 days (OR = 35.0, 95% CI 17.3-70.7), death within 90 days (OR = 7.27, 95% CI 2.83-18.7), and led to 23 days (95% CI 19.7-26.3) of additional hospitalization and $61,681 (95$24,113 (95% 4,521-43,704) of additional charges.The attributable impact of S. aureus and methicillin-resistance on outcomes of surgical patients is substantial. Preventing a single case of SSI due to MRSA can save hospitals as much as $60,000

Fluoroquinolones Protective against Cephalosporin Resistance in Gram-negative Nosocomial Pathogens

In a matched case-control study, we studied the effect of prior receipt of fluoroquinolones on isolation of three third-generation cephalosporin-resistant gram-negative nosocomial pathogens. Two hundred eighty-two cases with a third-generation cephalosporin-resistant pathogen (203 with Enterobacter spp., 50 with Pseudomonas aeruginosa, and 29 with Klebsiella pneumoniae) were matched on length of stay to controls in a 1:2 ratio. Case-patients and controls were similar in age (mean 62 years) and sex (54% male). Variables predicting third-generation cephalosporin resistance were surgery (p = 0.005); intensive care unit stay (p < 0.001); and receipt of a β-lactam/β-lactamase inhibitor (p < 0.001), a ureidopenicillin (p = 0.002), or a third-generation cephalosporin (p < 0.001). Receipt of a fluoroquinolone was protective against isolation of a third-generation cephalosporin-resistant pathogen (p = 0.005). Interventional studies are required to determine whether replacing third-generation cephalosporins with fluoroquinolones will be effective in reducing cephalosporin resistance and the effect of such interventions on fluoroquinolone resistance

The Impact of Multidrug-Resistant Organisms on Outcomes in Patients with Diabetic Foot Infections

Background. Multidrug-resistant organisms (MDROs) are important diabetic foot infection (DFI) pathogens. This study evaluated the impact of DFIs associated with MDRO pathogens (DFI-MDRO) on clinical outcomes. Methods. Adults admitted to Detroit Medical Center from January 2012 to December 2015 with culture-positive DFI were included. Associations between outcomes and DFI-MDRO (evaluated as a single group that included methicillin-resistant Staphylococcus aureus [MRSA], vancomycin-resistant enterococci, Enterobacteriaceae resistant to third-generation cephalosporin [3GCR-EC], Acinetobacter baumannii, and Pseudomonas aeruginosa) were analyzed. Outcomes included above- and below-knee lower extremity amputation (LEA), readmissions, and mortality within a year after DFI. A propensity score predicting the likelihood of having DFI-MDRO was computed by comparing patients with DFI-MDRO with patients with DFI with non-MDRO pathogens (DFI-non-MDRO). Using conditional logistic regression, DFI-MDRO was analyzed as an independent variable after patients in the MDRO and non-MDRO groups were matched by propensity score. Results. Six hundred forty-eight patients were included, with a mean age ± SD of 58.4 ± 13.7. Most patients in the cohort presented with chronic infection (75%). DFI-MDRO occurred in greater than one-half of the cohort (n = 364, 56%), and MRSA was the most common MDRO (n = 224, 62% of the DFI-MDRO group). In propensity-matched analyses, DFI-MDRO was not associated with 1-year LEA or readmissions, but was associated with recurrent DFI episodes (odds ratio, 2.1; 95% confidence interval, 1.38–3.21). Conclusions. DFI-MDRO was associated with a 2-fold increased risk of recurrent DFI compared with patients with DFI-non-MDRO

In Vitro Assessment of Combined Polymyxin B and Minocycline Therapy against Klebsiella pneumoniae Carbapenemase (KPC)-Producing K. pneumoniae

ABSTRACT The multidrug resistance profiles of Klebsiella pneumoniae carbapenemase (KPC) producers have led to increased clinical polymyxin use. Combination therapy with polymyxins may improve treatment outcomes, but it is uncertain which combinations are most effective. Clinical successes with intravenous minocycline-based combination treatments have been reported for infections caused by carbapenemase-producing bacteria. The objective of this study was to evaluate the in vitro activity of polymyxin B and minocycline combination therapy against six KPC-2-producing K. pneumoniae isolates (minocycline MIC range, 2 to 32 mg/liter). Polymyxin B monotherapy (0.5, 1, 2, 4, and 16 mg/liter) resulted in a rapid reduction of up to 6 log in bactericidal activity followed by regrowth by 24 h. Minocycline monotherapy (1, 2, 4, 8, and 16 mg/liter) showed no reduction of activity of >1.34 log against all isolates, although concentrations of 8 and 16 mg/liter prolonged the time to regrowth. When the therapies were used in combination, rapid bactericidal activity was followed by slower regrowth, with synergy (60 of 120 combinations at 24 h, 19 of 120 combinations at 48 h) and additivity (43 of 120 combinations at 24 h, 44 of 120 combinations at 48 h) against all isolates. The extent of killing was greatest against the more susceptible polymyxin B isolates (MICs of ≤0.5 mg/liter) regardless of the minocycline MIC. The pharmacodynamic activity of combined polymyxin B-minocycline therapy against KPC-producing K. pneumoniae is dependent on polymyxin B susceptibility. Further in vitro and animal studies must be performed to fully evaluate the efficacy of this drug combination

Gram-Negative Bacteremia upon Hospital Admission: When Should Pseudomonas aeruginosa Be Suspected?

Background. Pseudomonas aeruginosa is an uncommon cause of community-acquired bacteremia among patients without severe immunodeficiency. Because tension exists between the need to limit unnecessary use of anti-pseudomonal agents and the need to avoid a delay in appropriate therapy, clinicians require better guidance regarding when to cover empirically for P. aeruginosa. We sought to determine the occurrence of and construct a model to predict P. aeruginosa bacteremia upon hospital admission. Methods. A retrospective study was conducted in 4 tertiary care hospitals. Microbiology databases were searched to find all episodes of bacteremia caused by gram-negative rods (GNRs) ⩽48 h after hospital admission. Patient data were extracted from the medical records of 151 patients with P. aeruginosa bacteremia and of 152 randomly selected patients with bacteremia due to Enterobacteriaceae. Discriminative parameters were identified using logistic regression, and the probabilities of having P. aeruginosa bacteremia were calculated. Results. P. aeruginosa caused 6.8% of 4114 unique patient episodes of GNR bacteremia upon hospital admission (incidence ratio, 5 cases per 10,000 hospital admissions). Independent predictors of P. aeruginosa bacteremia were severe immunodeficiency, age >90 years, receipt of antimicrobial therapy within past 30 days, and presence of a central venous catheter or a urinary device. Among 250 patients without severe immunodeficiency, if no predictor variables existed, the likelihood of having P. aeruginosa bacteremia was 1:42. If ⩾2 predictors existed, the risk increased to nearly 1:3. Conclusions. P. aeruginosa bacteremia upon hospital admission in patients without severe immunodeficiency is rare. Among immunocompetent patients with suspected GNR bacteremia who have ⩾2 predictors, empirical anti-pseudomonal treatment is warrante