In-depth analysis of T2Bacteria positive results in patients with concurrent negative blood culture: a case series.

BACKGROUND: T2Bacteria assay uses T2 magnetic resonance (T2MR) technology for the rapid diagnosis of bacterial bloodstream infections (BSIs). This FDA cleared technology can detect 5 of the most prevalent pathogens causing bacteremia (Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Enterococcus faecium). Because the significance of discordant results between the T2Bacteria assay and blood culture (BC) remains a challenge, in this case series we reviewed the medical records of patients who had a positive T2Bacteria test and a concurrent negative BC. METHODS: Among 233 participants, we identified 20 patients with 21 (9%) discordant T2Bacteria-positive/BC-negative (T2+/BC-) results. We classified these results based on clinical cultures and clinical evidence. RESULTS: When we analyzed these 21 discordant results in-depth, 11 (52.5%) fulfilled criteria for probable BSI, 4 (19%) for possible BSI, and 6 (28.5%) were presumptive false positives. Among the probable/possible BSIs, discordant results were often associated with patients diagnosed with closed space and localized infections [pyelonephritis (n = 7), abscess (n = 4), pneumonia (n = 1), infected hematoma (n = 1), and osteomyelitis (n = 1)]. Also, within the preceding 2 days of the T2+/BC- blood sample, 80% (16/20) of the patients had received at least one dose of an antimicrobial agent which was active against the T2Bacteria-detected pathogen. CONCLUSIONS: In the majority of discrepant results, the T2Bacteria assay detected a plausible pathogen that was supported by clinical and/or microbiologic data. Discrepancies appear to be associated with closed space and localized infections and the recent use of effective antibacterial agents. The clinical significance and potential implications of such discordant results should be further investigated.

A Systematic Review and Meta-analysis of Antibiotic Treatment Duration for Bacteremia Due to Enterobacteriaceae.

The duration of antibiotic therapy for bacteremia due to Enterobacteriaceae is not well defined. We sought to evaluate the clinical outcomes with shorter- versus longer-course treatment. We performed a systematic search of the PubMed and EMBASE databases through May 2018. Studies presenting comparative outcomes between patients receiving antibiotic treatment for ≤10 days ("short-course") and those treated for >10 days ("long-course") were considered eligible. Four retrospective cohort studies and one randomized controlled trial comprising 2,865 patients met the inclusion criteria. The short- and long-course antibiotic treatments did not differ in 30-day all-cause mortality (1,374 patients; risk ratio [RR] = 0.99; 95% confidence interval [CI], 0.69 to 1.43), 90-day all-cause mortality (1,750 patients; RR = 1.16; 95% CI, 0.81 to 1.66), clinical cure (1,080 patients; RR = 1.02; 95% CI, 0.96 to 1.08), or relapse at 90 days (1,750 patients; RR = 1.08; 95% CI, 0.69 to 1.67). In patients with bacteremia due to Enterobacteriaceae, the short- and long-course antibiotic treatments did not differ significantly in terms of clinical outcomes. Further well-designed studies are needed before treatment for 10 days or less is adopted in clinical practice.

Systematic Review and Meta-analysis of the Efficacy of Short-Course Antibiotic Treatments for Community-Acquired Pneumonia in Adults.

The duration of therapy for community-acquired pneumonia (CAP) remains undefined. We sought to investigate whether short-course antibiotic treatment for CAP is associated with favorable clinical outcomes in adult patients. We systematically searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for studies comparing the effectiveness and safety between treatment regimens administered for ≤6 days and ≥7 days. We defined treatment for ≤6 days as short-course treatment and treatment for ≥7 days as long-course treatment. Twenty-one clinical trials (4,861 clinically evaluable patients) were included, and 19 out of 21 trials were randomized. Clinical cure was similar between the compared groups (4,069 patients, risk ratio [RR] = 0.99 [95% confidence interval {CI}, 0.97 to 1.01]), irrespective of patient setting (RR = 0.98 [95% CI, 0.96 to 1.00] for the outpatient setting and RR = 1.00 [95% CI, 0.92 to 1.09] for the inpatient setting) or severity of pneumonia (RR = 1.05 [95% CI, 0.96 to 1.14]). Also, relapses were similar between the short- and long-course treatment groups (1,923 patients, RR = 0.67 [95% CI, 0.30 to 1.46]). Short-course treatment was associated with fewer serious adverse events (1,923 patients, RR = 0.73 [95% CI, 0.55 to 0.97]) and, importantly, resulted in lower mortality than long-course treatment (2,802 patients, RR = 0.52 [95% CI, 0.33 to 0.82]). In CAP, short-course antibiotic treatment (≤6 days) is as effective as and potentially superior to, in terms of mortality and serious adverse events, longer-course treatment.

Impact of oseltamivir use on the reduction of complications in patients with influenza: a prospective study.

To evaluate the factors associated with oseltamivir prescription and to study the effectiveness of oseltamivir in reducing influenza-related complications. A prospective cohort study using the SOS Doctors (a network of physicians who perform house-call visits in Attica, Greece). Patients with confirmed or clinically suspected influenza were followed up to 14 days during the 2011-2012 influenza period. 410 patients with confirmed or suspected influenza were included. Healthy adults were mainly enrolled, with a median age of 44 years. Influenza diagnosis was mainly based on clinical criteria (65.8 % of patients). Oseltamivir was prescribed for 45.4 % of them. In a multivariate analysis, prescription of oseltamivir was associated with the attending physician (p < 0.001), positive influenza test (p < 0.001) and diabetes (p = 0.027). Data on complications were available for 351 patients, and 50 (15.8 %) of them reported at least one. Seven patients required hospitalization. Types of complications (pneumonia, bronchitis, etc.) were not significantly different between patients receiving and those not receiving oseltamivir. In the multivariate analysis, higher oseltamivir prescription rate was associated with fewer complications (p < 0.001). Bearing in mind the limitations of a non-randomized study, in a real-life setting, oseltamivir prescription and the rate of complications in patients with influenza were associated with the attending physician, underlying diseases and diagnostic tests. Overall, when the frequency of oseltamivir prescription increased, the influenza-related complications decreased.

Hepatitis B vaccine alone or with hepatitis B immunoglobulin in neonates of HBsAg+/HBeAg- mothers: a systematic review and meta-analysis.

OBJECTIVES: The cost-effectiveness of augmenting immunization against hepatitis B infection with hepatitis B immunoglobulin (HBIG) remains controversial, particularly for the subpopulation of babies of HBsAg+/HBeAg- mothers that are considered as low-infective. We aimed to evaluate the effectiveness of vaccine alone compared with vaccine plus HBIG for the immunization of babies of HBsAg+/HBeAg- mothers. METHODS: We searched PubMed, Scopus and Cochrane Central Register of Controlled Trials databases to identify studies comparing the effectiveness of combined immunization (vaccine plus HBIG) with vaccine alone in neonates of HBsAg+/HBeAg- mothers. A systematic review and meta-analysis of eligible studies was performed. RESULTS: A total of nine eligible studies were identified (four randomized controlled trials). No difference was found regarding the primary outcome of our meta-analysis, namely occurrence of hepatitis B infection, between neonates who received vaccine only, compared with those who received both vaccine and HBIG (four studies, 3426 patients, OR=0.82, 95% CI=0.41-1.64). This finding was consistent with regards to seroprotection rate (four studies, 1323 patients, OR=1.24, 95% CI=0.97-1.58). Safety data were not reported in the included studies. CONCLUSIONS: The available limited published evidence suggests that vaccine alone seems to be equally effective to the combination of HBIG and hepatitis B vaccine for neonates of HBsAg+/HBeAg- mothers in preventing infection. Further studies are needed in order to clarify the potential benefit of combined immunization to this specific subgroup of patients.

Deaths attributable to carbapenem-resistant Enterobacteriaceae infections.

We evaluated the number of deaths attributable to carbapenem-resistant Enterobacteriaceae by using studies from around the world published before April 9, 2012. Attributable death was defined as the difference in all-cause deaths between patients with carbapenem-resistant infections and those with carbapenem-susceptible infections. Online databases were searched, and data were qualitatively synthesized and pooled in a metaanalysis. Nine studies met inclusion criteria: 6 retrospective case-control studies, 2 retrospective cohort studies, and 1 prospective cohort study. Klebsiella pneumoniae was the causative pathogen in 8 studies; bacteremia was the only infection in 5 studies. We calculated that 26%-44% of deaths in 7 studies were attributable to carbapenem resistance, and in 2 studies, which included bacteremia and other infections, -3% and -4% of deaths were attributable to carbapenem resistance. Pooled outcomes showed that the number of deaths was significantly higher in patients with carbapenem-resistant infections and that the number of deaths attributable to carbapenem resistance is considerable.

Antibiotic treatment of infections due to carbapenem-resistant Enterobacteriaceae: systematic evaluation of the available evidence.

We sought to evaluate the effectiveness of the antibiotic treatment administered for infections caused by carbapenemase-producing Enterobacteriaceae. The PubMed and Scopus databases were systematically searched. Articles reporting the clinical outcomes of patients infected with carbapenemase-producing Enterobacteriaceae according to the antibiotic treatment administered were eligible. Twenty nonrandomized studies comprising 692 patients who received definitive treatment were included. Almost all studies reported on Klebsiella spp. In 8 studies, the majority of infections were bacteremia, while pneumonia and urinary tract infections were the most common infections in 12 studies. In 10 studies, the majority of patients were critically ill. There are methodological issues, including clinical heterogeneity, that preclude the synthesis of the available evidence using statistical analyses, including meta-analysis. From the descriptive point of view, among patients who received combination treatment, mortality was up to 50% for the tigecycline-gentamicin combination, up to 64% for tigecycline-colistin, and up to 67% for carbapenem-colistin. Among the monotherapy-treated patients, mortality was up to 57% for colistin and up to 80% for tigecycline. Certain regimens were administered to a small number of patients in certain studies. Three studies reporting on 194 critically ill patients with bacteremia showed individually significantly lower mortality in the combination arm than in the monotherapy arm. In the other studies, no significant difference in mortality was recorded between the compared groups. Combination antibiotic treatment may be considered the optimal option for severely ill patients with severe infections. However, well-designed randomized studies of specific patient populations are needed to further clarify this issue.

Proportion of extended-spectrum ß-lactamase (ESBL)-producing isolates among Enterobacteriaceae in Africa: evaluation of the evidence--systematic review.

OBJECTIVES: Extended-spectrum ß-lactamases (ESBLs) have become widespread around the world. We sought to evaluate the proportion of ESBL-producing isolates among Enterobacteriaceae in Africa. METHODS: A systematic search in the PubMed and Scopus databases was performed in order to identify studies providing the proportion of ESBL-producing isolates among patients either infected or colonized with Enterobacteriaceae. In an effort to incorporate contemporary data, only studies published from 2005 onwards and, among them, only those including isolates that were recovered from 2000 onwards were eligible. RESULTS: Twenty-six studies (409 ,215 isolates) from 13 African countries met the inclusion criteria. The proportion of ESBL-producing isolates among 13 studies reporting on isolates from a urinary source varied from 1.5% to 22.8%. Four other studies evaluated various clinical samples from different hospitals, showing that the proportion varied from 12.8% to 21.1%. Last, the proportions were 0.7%, 14%, 15.2% and 75.8%, respectively, in four studies evaluating patients with bloodstream infection. In particular, the proportion was 0.7% in a study from Malawi where ceftriaxone was the only available cephalosporin and was 75.8% in a study from Egypt that included only patients from intensive care units. In total, the proportion of ESBL-producing isolates was <15% in 16 out of 26 studies. CONCLUSIONS: Data originating from a small number of African countries suggest that the proportion of ESBL-producing isolates among Enterobacteriaceae may not be high in Africa, but is certainly not negligible. Further studies are needed from countries where no or limited relevant data are available.

Clinical outcomes with extended or continuous versus short-term intravenous infusion of carbapenems and piperacillin/tazobactam: a systematic review and meta-analysis.

We sought to study whether the better pharmacokinetic and pharmacodynamic (PK/PD) properties of carbapenems and piperacillin/tazobactam, when the duration of infusion is longer, were associated with lower mortality. PubMed and Scopus were searched for studies reporting on patients treated with extended (≥3 hours) or continuous (24 hours) versus short-term duration (20-60 minutes) infusions of carbapenems or piperacillin/tazobactam. Fourteen studies were included (1229 patients). Mortality was lower among patients receiving extended or continuous infusion of carbapenems or piperacillin/tazobactam compared to those receiving short-term (risk ratio [RR], 0.59; 95% confidence interval [CI], .41-.83). Patients with pneumonia who received extended or continuous infusion had lower mortality than those receiving short-term infusion (RR, 0.50; 95% CI, 0.26-0.96). Data for other specific infections were not available. The available evidence from mainly nonrandomized studies suggests that extended or continuous infusion of carbapenems or piperacillin/tazobactam was associated with lower mortality. Well-designed randomized controlled trials are warranted to confirm these findings before such approaches become widely used.

Evaluation of antimicrobial susceptibility of Enterobacteriaceae causing urinary tract infections in Africa.

Our objective was to evaluate the antimicrobial susceptibility of Enterobacteriaceae causing urinary tract infections (UTIs) in adults in Africa. The PubMed database was systematically searched to identify relevant studies published after 2000. Google, World Health Organization, and African Field Epidemiology networks were also searched. Twenty-eight studies, accounting for 381,899 urine isolates from 14 African countries, met the inclusion criteria. Escherichia coli, Klebsiella spp., and Proteus spp. were the most commonly encountered uropathogens. Cefotaxime, imipenem, fosfomycin, and ciprofloxacin were the antibiotics with the highest activity against E. coli isolates from outpatients, with susceptibility being 92 to 99, 100, 100, and 68 to 91%, respectively. The susceptibility among Klebsiella spp. isolates from outpatients varied from 80 to 100% for amikacin and from 53 to 100% for ciprofloxacin, while susceptibility was 74 to 78, 97, and 77% for ciprofloxacin, amikacin, and fosfomycin, respectively, among Klebsiella species isolates from inpatients or patients with hospital-acquired UTIs. With regard to Proteus spp., the highest activity was observed among fluoroquinolones; 71 to 100% of the P. mirabilis isolates were susceptible to ciprofloxacin in four studies, and 74 to 100% of the P. vulgaris isolates were susceptible to ofloxacin in two studies. The currently available evidence suggests that the antimicrobial susceptibility patterns of Enterobacteriaceae uropathogens in African countries were similar to those in countries of southeast Europe. Further original studies are warranted from African countries for which there is limited published data.

A prospective study of characteristics and outcomes of bacteremia in patients with solid organ or hematologic malignancies.

OBJECTIVE: To study the epidemiology and outcomes of bacteremia in patients with hematologic or solid organ malignancies cared for at the University Hospital of Heraklion, Greece. METHODS: This prospective study was conducted during a 4-year period (2007-2011). Patients with bacterial and fungal blood stream infections were followed until discharge. Mortality was the primary outcome, while duration of hospitalization, relapses, time to relapse, and defervescence were the secondary outcomes. RESULTS: Ninety-nine patients with neoplasia (104 episodes) were included. Bacteremia developed mainly in patients with hematologic malignancies (56%). Secondary bacteremias due to respiratory and urinary tract infections were most commonly identified. Gram-negative bacteria were the predominantly isolated pathogens (65%); Pseudomonas spp. was the most common cause (19%), followed closely by E. coli (18%) and Klebsiella pneumoniae (17%). In-hospital mortality was 26.2%. No differences in mortality were seen among patients in different subgroups according to isolated bacteria (according to Gram's stain, species, or number of isolated bacteria in positive cultures), hematologic or solid organ malignancy, neutropenia, and primary or secondary bacteremia. However, patients with bacteremia due to extensively drug resistant bacteria had higher mortality than patients with bacteremia due to multidrug resistant or susceptible pathogens. Patients required a prolonged period of hospitalization (21.8 ± 14.9 days), which was complicated with relapses or reinfections in another body site in 27 % of them. CONCLUSION: Gram-negative bacteria were the predominantly isolated pathogens from patients with cancer in our population. The overall mortality remains high.

Genomic reconstruction and directed interventions in a multidrug-resistant Shigellosis outbreak in Seattle, WA, USA: a genomic surveillance study.

BACKGROUND: Shigella spp have been associated with community-wide outbreaks in urban settings. We analysed a sustained shigellosis outbreak in Seattle, WA, USA, to understand its origins and mechanisms of antimicrobial resistance, define ongoing transmission patterns, and optimise strategies for treatment and infection control. METHODS: We did a retrospective study of all Shigella isolates identified from stool samples at the clinical laboratories at Harborview Medical Center and University of Washington Medical Center (Seattle, WA, USA) from May 1, 2017, to Feb 28, 2022. We characterised isolates by species identification, phenotypic susceptibility testing, and whole-genome sequencing. Demographic characteristics and clinical outcomes of the patients were retrospectively examined. FINDINGS: 171 cases of shigellosis were included. 78 (46%) patients were men who have sex with men (MSM), and 88 (52%) were people experiencing homelessness (PEH). Although 84 (51%) isolates were multidrug resistant, 100 (70%) of 143 patients with data on antimicrobial therapy received appropriate empirical therapy. Phylogenomic analysis identified sequential outbreaks of multiple distinct lineages of Shigella flexneri and Shigella sonnei. Discrete clonal lineages (ten in S flexneri and nine in S sonnei) and resistance traits were responsible for infection in different at-risk populations (ie, MSM, PEH), enabling development of effective guidelines for empirical treatment. The most prevalent lineage in Seattle was probably introduced to Washington State via international travel, with subsequent domestic transmission between at-risk groups. INTERPRETATION: An outbreak in Seattle was driven by parallel emergence of multidrug-resistant strains involving international transmission networks and domestic transmission between at-risk populations. Genomic analysis elucidated not only outbreak origin, but directed optimal approaches to testing, treatment, and public health response. Rapid diagnostics combined with detailed knowledge of local epidemiology can enable high rates of appropriate empirical therapy even in multidrug-resistant infection. FUNDING: None.

Impact of antibiotic MIC on infection outcome in patients with susceptible Gram-negative bacteria: a systematic review and meta-analysis.

The objective of this study was to analyze the impact of MIC values within the susceptible range of antibiotics on the outcomes of patients with Gram-negative infections. The PubMed and Scopus electronic databases were searched. We identified 13 articles (1,469 patients) that studied the impact of antibiotic MICs on the outcomes of infections; ß-lactams were studied in 10 of them. Infections due to Salmonella enterica strains with high fluoroquinolone MICs were associated with more treatment failures than those due to strains with low MICs (relative risk [RR], 5.75; 95% confidence interval [CI], 1.77 to 18.71). Among non-Salmonella enterobacteriaceae, there was no difference in treatment failures depending on the MIC value (RR, 1.18; 95% CI, 0.71 to 1.97); however, a higher all-cause mortality was observed for patients infected with strains with high MICs (RR, 2.03; 95% CI, 1.05 to 3.92). More treatment failures were observed for patients infected with nonfermentative Gram-negative bacilli when strains had high MICs (RR, 5.54; 95% CI, 2.72 to 11.27). The mortality rate for patients with infections with Gram-negative nonfermentative bacilli with high MICs was also higher than for those with low MICs (RR, 2.39; 95% CI, 1.19 to 4.81). The limited available data suggest that there is an association between high MICs, within the susceptible range, and adverse outcomes for patients with Gram-negative infections.

Carbapenems versus alternative antibiotics for the treatment of bacteraemia due to Enterobacteriaceae producing extended-spectrum ß-lactamases: a systematic review and meta-analysis.

OBJECTIVES: To study the comparative mortality associated with carbapenems and alternative antibiotics for the treatment of patients with extended-spectrum ß-lactamase (ESBL)-positive Enterobacteriaceae bacteraemia. METHODS: We searched systematically PubMed and Scopus databases for studies providing data for mortality among patients treated with carbapenems, ß-lactam/ß-lactamase inhibitor combinations (BL/BLIs) or non-BL/BLIs (mainly cephalosporins and fluoroquinolones), preferably as monotherapy. Studies focusing on patients of all ages with community- and healthcare-associated bacteraemia were eligible. Data were pooled using the technique of meta-analysis. RESULTS: Twenty-one articles, studying 1584 patients, were included. Escherichia coli and Klebsiella pneumoniae were the most commonly studied bacteria. Delay in appropriate treatment up to 6 days was reported. Carbapenems were used mainly as definitive therapy. Carbapenems were associated with lower mortality than non- BL/BLIs for definitive [risk ratio (RR) 0.65, 95% CI 0.47-0.91] and empirical (RR 0.50, 95% CI 0.33-0.77) treatment. No statistically significant differences in mortality were found between carbapenems and BL/BLIs administered as definitive (RR 0.52, 95% 0.23-1.13) or empirical (RR 0.91, 95% CI 0.66-1.25) treatment. BL/BLIs were not associated with lower mortality than non-BL/BLIs administered either definitively (RR 1.59, 95% 0.83-3.06) or empirically (RR 0.82, 95% 0.48-1.41). Data regarding subgroups according to the setting, comorbidity and bacterial species could not be extracted. CONCLUSIONS: Based on data from non-randomized studies, carbapenems may be considered the treatment of choice for empirical treatment of patients with ESBL-producing Enterobacteriaceae bacteraemia. The role of BL/BLIs should be further evaluated for definitive treatment. Further research should focus on faster identification of ESBL-positive pathogens and potential differences in the treatment of each bacterial species.

A Closer Look at the Laboratory Impact of Utilizing ePlex Blood Culture Identification Panels: a Workflow Analysis Using Rapid Molecular Detection for Positive Blood Cultures.

Rapid identification of pathogens is critical in bloodstream infections. We evaluated the diagnostic performance of the GenMark Dx ePlex blood culture identification (BCID) panels and the adoption of the ePlex system into the clinical laboratory workflow. Nonduplicate remnant specimens of positive blood cultures were prospectively tested using ePlex panels between January and March 2020. A total of 313 unique positive blood culture specimens were tested. The identified organisms consisted of 98 Gram-negative rods (GNR), 90 Gram-positive cocci (GPC) in clusters, 62 GPC in chains, 21 Gram-positive rods, and 20 yeasts; 22 organisms were off panel. The positive percent agreement was 100% across all organisms tested after discordancy resolution, while the negative percent agreement was 100% across all targets except Corynebacterium spp., where it was 99.7%. The ePlex BCID panels accurately detected 5 pan targets and 42 antimicrobial resistance gene markers, including 31 mecA, 4 vanA, 6 CTX-M, and 1 KPC gene. The median times to result were calculated as 2.5 h for Xpert MRSA/SA in GPC in clusters, 9.5 h for Accelerate Pheno (identification and susceptibility) in GNR, 6 h for peptide nucleic acid fluorescent in situ hybridization [PNA-FISH] in yeasts, 27 h for the latex agglutination test in S. aureus, 29 h for Lancefield serotyping in GPC in chains, and 29 h for Vitek-MS in GNR. In our laboratory, the ePlex panels could substantially reduce the time to result for bloodstream infection (BSI) caused by Streptococcus spp., Enterococcus spp., and Candida spp. The highly accurate ePlex panels can help streamline laboratory efficiency in the blood bench workflow, reducing the time to result for identification of BSI pathogens. IMPORTANCE Sepsis is a leading cause of morbidity and mortality worldwide. Rapid identification of the causative agent is of critical importance for the prompt initiation of the appropriate antibiotic treatment. In this study, we evaluated the diagnostic performance of the GenMark Dx ePlex blood culture identification (BCID) panels and their adoption into the clinical laboratory workflow. We prospectively tested 313 blood culture isolates and found that ePlex BCID panels had a positive percent agreement of 100% across all organisms tested after discordancy resolution. The negative percent agreement was 100% across all targets except Corynebacterium spp., where it was 99.7%. This new rapid technology (turnaround time of ~90 min) can help streamline laboratory efficiency in the blood bench workflow, reducing the time to result for identification of BSI pathogens. Adoption should be individualized based on the needs of the patient population and capabilities of the laboratory.

Diagnostic Accuracy of Presurgical Staphylococcus aureus PCR Assay Compared with Culture and Post-PCR Implementation Surgical Site Infection Rates.

Nasal colonization with Staphylococcus aureus is a well-referenced risk factor for postoperative surgical site infections (SSIs). Our health care system that performs >40,000 surgeries per year assessed both the diagnostic accuracy of the BD MAX StaphSR assay (MAX StaphSR), a PCR-based test that detects and differentiates S. aureus and methicillin-resistant S. aureus (MRSA), compared with our standard of care culture and the subsequent clinical impact on SSIs 1 year after implementation. In addition, residual specimens were tested by broth-enriched culture. Performance parameters for all methods were determined using latent class analysis. Direct culture was the least sensitive for S. aureus (85.1%) and MRSA (76.7%), whereas the MAX StaphSR assay and broth-enriched culture had similar sensitivities (96.7%) for MRSA. Prospective assessment using MAX StaphSR during a 1-year, postimplementation period revealed a lower rate of SSIs per 100 targeted surgeries (0.3) compared with MRSA-only screening (1.10) and no screening (2.28) (P < 0.05 for StaphSR versus MRSA-only screening and StaphSR versus no testing). MRSA and methicillin-sensitive S. aureus SSIs occurred equally (n = 14 each). The MAX StaphSR assay provided accurate detection of both S. aureus and MRSA nasal colonization in presurgical patients, allowing infection prevention measures, including presurgical prophylaxis, to be implemented in a timely and consistent manner to avoid SSIs.

The cost-effectiveness of empirical antibiotic treatments for high-risk febrile neutropenic patients: A decision analytic model.

PURPOSE: Febrile neutropenia has a significant clinical and economic impact on cancer patients. This study evaluates the cost-effectiveness of different current empiric antibiotic treatments. METHODS: A decision analytic model was constructed to compare the use of cefepime, meropenem, imipenem/cilastatin, and piperacillin/tazobactam for treatment of high-risk patients. The analysis was performed from the perspective of U.S.-based hospitals. The time horizon was defined to be a single febrile neutropenia episode. Cost-effectiveness was determined by calculating costs and deaths averted. Cost-effectiveness acceptability curves for various willingness-to-pay thresholds (WTP), were used to address the uncertainty in cost-effectiveness. RESULTS: The base-case analysis results showed that treatments were equally effective but differed mainly in their cost. In increasing order: treatment with imipenem/cilastatin cost $52,647, cefepime $57,270, piperacillin/tazobactam $57,277, and meropenem $63,778. In the probabilistic analysis, mean costs were $52,554 (CI: $52,242-$52,866) for imipenem/cilastatin, $57,272 (CI: $56,951-$57,593) for cefepime, $57,294 (CI: $56,978-$57,611) for piperacillin/tazobactam, and $63,690 (CI: $63,370-$64,009) for meropenem. Furthermore, with a WTP set at $0 to $50,000, imipenem/cilastatin was cost-effective in 66.2% to 66.3% of simulations compared to all other high-risk options. DISCUSSION: Imipenem/cilastatin is a cost-effective strategy and results in considerable health care cost-savings at various WTP thresholds. Cost-effectiveness analyses can be used to differentiate the treatments of febrile neutropenia in high-risk patients.