The Time for Action Is Now: The Impact of Timing of Infectious Disease Consultation for Staphylococcus aureus Bacteremia.

This retrospective cohort study was performed to compare clinical outcomes between patients with Staphylococcus aureus bacteremia who received an early versus late infectious disease consultation. Early consultation resulted in significantly greater adherence to quality care indicators and shorter hospital stays.

Practical Guidance for Clinical Microbiology Laboratories: Viruses Causing Acute Respiratory Tract Infections.

Respiratory viral infections are associated with a wide range of acute syndromes and infectious disease processes in children and adults worldwide. Many viruses are implicated in these infections, and these viruses are spread largely via respiratory means between humans but also occasionally from animals to humans. This article is an American Society for Microbiology (ASM)-sponsored Practical Guidance for Clinical Microbiology (PGCM) document identifying best practices for diagnosis and characterization of viruses that cause acute respiratory infections and replaces the most recent prior version of the ASM-sponsored Cumitech 21 document, Laboratory Diagnosis of Viral Respiratory Disease, published in 1986. The scope of the original document was quite broad, with an emphasis on clinical diagnosis of a wide variety of infectious agents and laboratory focus on antigen detection and viral culture. The new PGCM document is designed to be used by laboratorians in a wide variety of diagnostic and public health microbiology/virology laboratory settings worldwide. The article provides guidance to a rapidly changing field of diagnostics and outlines the epidemiology and clinical impact of acute respiratory viral infections, including preferred methods of specimen collection and current methods for diagnosis and characterization of viral pathogens causing acute respiratory tract infections. Compared to the case in 1986, molecular techniques are now the preferred diagnostic approaches for the detection of acute respiratory viruses, and they allow for automation, high-throughput workflows, and near-patient testing. These changes require quality assurance programs to prevent laboratory contamination as well as strong preanalytical screening approaches to utilize laboratory resources appropriately. Appropriate guidance from laboratorians to stakeholders will allow for appropriate specimen collection, as well as correct test ordering that will quickly identify highly transmissible emerging pathogens.

A Stewardship Approach To Optimize Antimicrobial Therapy through Use of a Rapid Microarray Assay on Blood Cultures Positive for Gram-Negative Bacteria.

A Gram-negative (GN) blood culture microarray assay with an antimicrobial stewardship program (ASP) intervention was evaluated in 126 patients with GN bacteremia. The median time to optimal therapy was shorter in the postintervention group than in the preintervention group (49.3 h versus 38.5 h, respectively; P = 0.0199). ASP can utilize microarray technology to decrease the time to optimal antimicrobial therapy.

Stewardship approach for optimizing antimicrobial therapy through use of a rapid microarray assay on blood cultures positive for Enterococcus species.

Enterococci are a major cause of bloodstream infections in hospitalized patients and have limited antimicrobial treatment options due to their many resistance mechanisms. Molecular technologies have significantly shortened the time to enterococcal isolate identification compared with conventional methods. We evaluated the impact of rapid organism identification and resistance detection with the Verigene Gram-positive blood culture microarray assay on clinical and economic outcomes for patients with enterococcal bacteremia. A single-center preintervention/postintervention quasiexperimental study compared inpatients with enterococcal bacteremia from 1 February 2012 to 9 September 2012 (preintervention period) and 10 September 2012 to 28 February 2013 (postintervention period). An infectious disease and/or critical care pharmacist was contacted with the microarray assay results, and effective antibiotics were recommended. The clinical and economic outcomes for 74 patients were assessed. The mean time to appropriate antimicrobial therapy was 23.4 h longer in the preintervention group than in the postintervention group (P = 0.0054). A nonsignificant decrease in the mean time to appropriate antimicrobial therapy was seen for patients infected with vancomycin-susceptible Enterococcus isolates (P = 0.1145). For patients with vancomycin-resistant Enterococcus bacteremia, the mean time to appropriate antimicrobial therapy was 31.1 h longer in the preintervention group than in the postintervention group (P < 0.0001). In the postintervention group, the hospital length of stay was significantly 21.7 days shorter (P = 0.0484) and mean hospital costs were $60,729 lower (P = 0.02) than in the preintervention group. The rates of attributed deaths in the two groups were not statistically different. Microarray technology, supported by pharmacy and microbiology departments, can decrease the time to appropriate antimicrobial therapy, the hospital length of stay, and health care costs.

A Case Report of Melioidotic Prostatic Abscess in a Traveler.

A 48-year-old man who had returned from Panama 5 weeks prior presented with fever, dysuria, hematuria, flank pain, and suprapubic pain and was found to have a prostatic abscess. Abscess fluid obtained during transurethral drainage grew Burkholderia pseudomallei. Blood cultures remained negative, and imaging did not show any other visceral abscess. This presentation of primary prostatic melioidosis is extremely rare in this region.

Influence of Antimicrobial Stewardship and Molecular Rapid Diagnostic Tests on Antimicrobial Prescribing for Extended-Spectrum Beta-Lactamase- and Carbapenemase-Producing Escherichia coli and Klebsiella pneumoniae in Bloodstream Infection.

The objective of this study was to evaluate whether the addition of the Verigene BC-GN molecular rapid diagnostic test to standard antimicrobial stewardship practices (mRDT + ASP) decreased the time to optimal and effective antimicrobial therapy for patients with extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing Escherichia coli and Klebsiella pneumoniae bloodstream infections (BSI) compared to conventional microbiological methods with ASP (CONV + ASP). This was a multicenter, retrospective cohort study evaluating the time to optimal antimicrobial therapy in 5 years of patients with E. coli or K. pneumoniae BSI determined to be ESBL- or carbapenemase-producing by mRDT and/or CONV. Of the 378 patients included (mRDT + ASP, n = 164; CONV + ASP, n = 214), 339 received optimal antimicrobial therapy (mRDT + ASP, n = 161; CONV + ASP, n = 178), and 360 (mRDT + ASP, n = 163; CONV + ASP, n = 197) received effective antimicrobial therapy. The mRDT + ASP demonstrated a statistically significant decrease in the time to optimal antimicrobial therapy (20.5 h [interquartile range (IQR), 17.0 to 42.2 h] versus 50.1 h [IQR, 27.6 to 77.9 h]; P < 0.001) and the time to effective antimicrobial therapy (15.9 h [IQR, 1.9 to 25.7 h] versus 28.0 h [IQR, 9.5 to 56.7 h]; P < 0.001) compared to CONV + ASP, respectively. IMPORTANCE Our study supports the additional benefit of molecular rapid diagnostic test in combination with timely antimicrobial stewardship program (ASP) intervention on shortening the time to both optimal and effective antimicrobial therapy in patients with ESBL- or carbapenemase-producing Escherichia coli and Klebsiella pneumoniae bloodstream infections, compared to conventional microbiological methods and ASP. Gram-negative infections are associated with significant morbidity and mortality, often resulting in life-threatening organ dysfunction. Both resistance phenotypes confer resistance to many of our first-line antimicrobial agents with carbapenemase-producing Enterobacterales requiring novel beta-lactam and beta-lactamase inhibitor combinations or other susceptible non-beta-lactam antibiotics for treatment. National resistance trends in a cohort of hospitalized patients at U.S. hospitals during our study period demonstrate the increasing incidence of both resistance phenotypes, reinforcing the generalizability and timeliness of such analysis.

Molecular surveillance of methicillin-resistant Staphylococcus aureus genomes in hospital unexpectedly reveals discordance between temporal and genetic clustering.

BACKGROUND: The objective of this study was to identify sources and linkages among methicillin-resistant Staphylococcus aureus infections using whole-genome sequencing (WGS). METHODS: A total of 56 samples were obtained from all patients with a confirmed MRSA infection over 6 months at University of Florida-Health Jacksonville. Samples were cultured and sequenced; data was analyzed on an automated cloud-based platform. Genetic Clusters were defined as <40 single nucleotide polymorphisms. Temporal Clusters were defined as ≥5 MRSA cases over 3 days. RESULTS: We found 7 Genetic Clusters comprising 15 samples. Four Genetic Clusters contained patients with non-overlapping stays (3-10 weeks apart), 3 of which contained patients who shared the same Unit. We also found 5 Temporal Clusters comprising 23 samples, although none of the samples were genetically related. DISCUSSION: Results showed that temporal clustering may be a poor indicator of genetic linkage. Shared epidemiological characteristics between patients in Genetic Clusters may point toward previously unidentified hospital sources. Repeated observation of related strains is also consistent with ongoing MRSA transmission within the surrounding high-risk community. CONCLUSIONS: WGS is a valuable tool for hospital infection prevention and control.

Mixed flora: indication for therapy or early warning sign?

"Mixed flora" is a commonly returned result yielding not in either indication for therapy or identification of potential causative organisms. We sought to determine whether mixed flora (MF) was in fact a harbinger of impending pneumonia or a benign result that could be therapeutically ignored. Bronchoalveolar lavage (BAL) results of injured adults undergoing mechanical ventilation in a trauma intensive care unit were stratified by identified organisms and by colony counts. The incidence of mixed flora as a component of the specimen report was compared for diagnostic (greater than 10(5) colony forming units/mL) versus nondiagnostic results using chi2 accepting P < 0.05 as significant. Nondiagnostic specimens were then stratified as MF only or MF and other identified pathogenic organisms. This group was further evaluated to determine the use of antibiotic therapy and development of pneumonia. Finally, patients with nondiagnostic reports and subsequent BAL were analyzed to determine specific species if subsequent BAL were required or if later pneumonia occurred. During 2007, 159 BALs were performed on injured patients of which 93 were diagnostic for pneumonia, whereas 66 were nondiagnostic. Of the diagnostic specimens, 15 (16%) included mixed flora. Of the 66 nondiagnostic specimens, 39 (59%) contained mixed flora. Nine (60%) of the 15 with diagnostic mixed flora were started on antibiotic therapy for an average of 6.2 days. The remaining 39 (82%) patients with mixed flora received no antibiotic therapy and never developed pneumonia. These data demonstrate that in the absence of diagnostic threshold of an identifiable pathogenic organism, therapy for pneumonia should not be instituted or continued.

Clinical impact of a pharmacist-led antimicrobial stewardship initiative evaluating patients with Clostridioides difficile colitis.

Clostridioides difficile is the most common cause of healthcare-associated infection and gastroenteritis-associated death in the USA. Adherence to guideline recommendations for treatment of severe C. difficile infection (CDI) is associated with improved clinical success and reduced mortality. The purpose of this study was to determine whether implementation of a pharmacist-led antimicrobial stewardship program (ASP) CDI initiative improved adherence to CDI treatment guidelines and clinical outcomes. This was a single-center, retrospective, quasi-experimental study evaluating patients with CDI before and after implementation of an ASP initiative involving prospective audit and feedback in which guideline-driven treatment recommendations were communicated to treatment teams and documented in the electronic health record via pharmacy progress notes for all patients diagnosed with CDI. The primary endpoint was the proportion of patients treated with guideline adherent definitive regimens within 72 hours of CDI diagnosis. Secondary objectives were to evaluate the impact on clinical outcomes, including length of stay (LOS), infection-related LOS, 30-day readmission rates, and all-cause, in-hospital mortality. A total of 233 patients were evaluated. The proportion of patients on guideline adherent definitive CDI treatment regimen within 72 hours of diagnosis was significantly higher in the post-interventional group (pre: 42% vs post: 58%, p=0.02). No differences were observed in clinical outcomes or proportions of patients receiving laxatives, promotility agents, or proton pump inhibitors within 72 hours of diagnosis. Our findings demonstrate that a pharmacist-led stewardship initiative improved adherence to evidence-based practice guidelines for CDI treatment.

Whole-genome sequencing for outbreak investigations of methicillin-resistant Staphylococcus aureus in the neonatal intensive care unit: time for routine practice?

BACKGROUND Infants in the neonatal intensive care unit (NICU) are at increased risk for methicillin-resistant Staphylococcus aureus (MRSA) acquisition. Outbreaks may be difficult to identify due in part to limitations in current molecular genotyping available in clinical practice. Comparison of genome-wide single nucleotide polymorphisms (SNPs) may identify epidemiologically distinct isolates among a population sample that appears homogenous when evaluated using conventional typing methods. OBJECTIVE To investigate a putative MRSA outbreak in a NICU utilizing whole-genome sequencing and phylogenetic analysis to identify recent transmission events. DESIGN Clinical and surveillance specimens collected during clinical care and outbreak investigation. PATIENTS A total of 17 neonates hospitalized in a 43-bed level III NICU in northeastern Florida from December 2010 to October 2011 were included in this study. METHODS We assessed epidemiological data in conjunction with 4 typing methods: antibiograms, PFGE, spa types, and phylogenetic analysis of genome-wide SNPs. RESULTS Among the 17 type USA300 isolates, 4 different spa types were identified using pulsed-field gel electrophoresis. Phylogenetic analysis identified 5 infants as belonging to 2 clusters of epidemiologically linked cases and excluded 10 unlinked cases from putative transmission events. The availability of these results during the initial investigation would have improved infection control interventions. CONCLUSION Whole-genome sequencing and phylogenetic analysis are invaluable tools for epidemic investigation; they identify transmission events and exclude cases mistakenly implicated by traditional typing methods. When routinely applied to surveillance and investigation in the clinical setting, this approach may provide actionable intelligence for measured, appropriate, and effective interventions.

Evaluation of an antimicrobial stewardship approach to minimize overuse of antibiotics in patients with asymptomatic bacteriuria.

An antimicrobial stewardship educational initiative provided to physicians and pharmacists was evaluated at an academic medical center to minimize inappropriate treatment of asymptomatic bacteriuria (ASB). A significant decrease in empirical antimicrobial use for ASB was observed after education. Multifaceted educational initiatives can reduce inappropriate antimicrobial treatment of ASB.

Risk stratification for the development of a subsequent pneumonia after a nondiagnostic bronchoalveolar lavage.

BACKGROUND: Broncho-alveolar lavage (BAL) is an invasive bedside procedure to define type and concentration of pathologic organisms causing ventilator associated pneumonia (VAP). We evaluated if the absence of pathogens on final results represented a lavage aspect of the BAL as a therapeutic procedure to eliminate organisms. METHODS: BAL results collected from 2008 to 2009 were stratified as positive (POS) ≥ 100,000 cfu), indeterminate (INT) ≤ 100,000 cfu pathologic organisms, or negative defined as mixed flora (MF) or sterile (STR). The INT, MF, and STR results were assessed by incidence of a subsequent POS sample. RESULTS: Nine-hundred forty-nine BALs performed on 490 SICU patients were interpreted as POS in 227 patients (46%). 237 non- POS patients needed a subsequent BAL. Any pathogen on the first BAL (INT group) indicates a high likelihood for subsequent BAL which will be POS. Monthly cumulative sum analysis (CUSUM) of yield was unable to identify any specific period in which BAL performance varied from trend. CONCLUSION: MF and STR represent adequate sampling of secretions that are clinically benign. Any pathogen, regardless of concentration, should be considered a biomarker for future pneumonia. CUSUM analysis suggest better training in timing and indication may decrease unnecessary procedures yielding negative results.

Mycobacterium tuberculosis osteomyelitis in a patient with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS): a case report.

The incidence of tuberculosis is increasing in the United States. Extra-pulmonary involvement is more common in patients with HIV/AIDS. The diagnosis of Tuberculosis osteomyelitis requires a high degree of suspicion for accurate and timely diagnosis.We present a case of a 49 year old Caucasian male with HIV/AIDS who presented with a four-month history of soft tissue swelling in the left proximal thigh unresponsive to various broad spectrum antibiotics who was eventually diagnosed with Mycobacterium tuberculosis osteomyelitis of the left proximal femur.