Pooled Antibiotic Susceptibility Testing Performs Within CLSI Standards for Validation When Measured Against Broth Microdilution and Disk Diffusion Antibiotic Susceptibility Testing of Cultured Isolates.

: While new methods for measuring antimicrobial susceptibility have been associated with improved patient outcomes, they should also be validated using standard protocols for error rates and other test metrics. The objective of this study was to validate a novel susceptibility assay for complicated and recurrent urinary tract infections (UTIs): pooled antibiotic susceptibility testing (P-AST). This assay was compared to broth microdilution (BMD) and disk diffusion (DD), following Clinical and Laboratory Standards Institute (CLSI) guidelines for assessment of error rates and agreement.

Evolution of Specimen Self-Collection in the COVID-19 Era: Implications for Population Health Management of Infectious Disease.

Laboratory testing is an important component in the diagnosis of respiratory tract infections such as with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). However, specimen collection not only risks exposure of health care workers and other patients to infection, but also necessitates use of personal protective equipment that may be in short supply during periods of heightened disease activity. Self-collection of nasal or oropharyngeal swabs offers an alternative to address these drawbacks.

Detection of high-risk human papillomavirus infection in tonsillar specimens using 2 commercially available assays.

THE OBJECTIVE OF THE STUDY IS TO DETERMINE THE PREVALENCE OF HIGH-RISK HUMAN PAPILLOMAVIRUS (HRHPV) INFECTION IN TONSILLAR SWABS AND TISSUE: Patients undergoing tonsillectomy for nonmalignant causes were enrolled. A flocked swab and fresh tissue were collected from the left and right tonsil of each patient. Specimens were tested for hrHPV DNA using the Roche cobas test and for the presence of E6/E7 messenger RNA using the Hologic Aptima hrHPV test.

Equal performance of self-collected and health care worker-collected pharyngeal swabs for group a streptococcus testing by PCR.

A process employing patient- or parent-collected pharyngeal swabs for group A Streptococcus (GAS) testing would expedite diagnosis and treatment, reduce patient exposure to the health care setting, and decrease health care costs. Our aim was to determine the concordance between patient- or parent-collected (self-collected) and health care worker (HCW)-collected pharyngeal swabs for detection of GAS by PCR. From 9 October 2012 to 21 March 2013, patients presenting with a sore throat meeting criteria for GAS testing and not meeting criteria for severe disease were offered the opportunity to collect their own pharyngeal swab.

Inhibition controls for qualitative real-time PCR assays: are they necessary for all specimen matrices?

A retrospective analysis of 386,706 specimens representing a variety of matrix types used in qualitative real-time PCR assays determined the overall inhibition rate to be 0.87% when the inhibition control was added preextraction to 5,613 specimens and 0.01% when the inhibition control was added postextraction but preamplification in 381,093 specimens.

PCR-electrospray ionization mass spectrometry for direct detection of pathogens and antimicrobial resistance from heart valves in patients with infective endocarditis.

Microbiological diagnosis is pivotal to the appropriate management and treatment of infective endocarditis. We evaluated PCR-electrospray ionization mass spectrometry (PCR/ESI-MS) for bacterial and candidal detection using 83 formalin-fixed paraffin-embedded heart valves from subjects with endocarditis who had positive valve and/or blood cultures, 63 of whom had positive valvular Gram stains. PCR/ESI-MS yielded 55% positivity with concordant microbiology at the genus/species or organism group level (e.

Effectiveness of patient-collected swabs for influenza testing.

Objective: To compare the effectiveness of self-collected and health care worker (HCW)-collected nasal swabs for detection of influenza viruses and determine the patients' preference for type of collection.

Patients And Methods: We enrolled adult patients presenting with influenzalike illness to the Emergency Department at Mayo Clinic, Rochester, Minnesota, from January 28, 2011, through April 30, 2011. Patients self-collected a midturbinate nasal flocked swab from their right nostril following written instructions.

Evaluation of the Bruker Biotyper and Vitek MS matrix-assisted laser desorption ionization-time of flight mass spectrometry systems for identification of nonfermenting gram-negative bacilli isolated from cultures from cystic fibrosis patients.

The Bruker Biotyper and Vitek MS matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) instruments were evaluated for the identification of nonfermenting gram-negative bacilli (NFGNB) by a blinded comparison to conventional biochemical or molecular methods. Two hundred NFGNB that were recovered from cultures from cystic fibrosis patients in the University of Iowa Health Care (UIHC) Microbiology Laboratory between 1 January 2006 and 31 October 2010 were sent to Mayo Clinic for analysis with the Bruker Biotyper (software version 3.0) and to bioMérieux for testing with Vitek MS (SARAMIS database version 3.

Optimized pathogen detection with 30- compared to 20-milliliter blood culture draws.

Using data from 23,313 patients, we assessed whether two blood culture sets of three bottles per set would detect more pathogens than two sets of two bottles per set and achieve similar sensitivity to collecting three sets of two bottles per set. We also compared the yield of aerobic and anaerobic bottles. Thirty milliliters of blood was distributed to one anaerobic and two aerobic bottles.

Effect of carbon dioxide on broth microdilution susceptibility testing of Brucella spp.

Since some strains of Brucella species may require carbon dioxide for growth, a multilaboratory study was conducted to compare broth microdilution susceptibility results using ambient air (AA) and 5% CO2 incubation conditions. Six antimicrobial agents were tested against 39 Brucella isolates. Aminoglycoside MICs tended to be 1 log2 dilution higher in CO2 than in AA; tetracycline-class MICs to be 1 log2 dilution lower in CO2.

Tuberculosis attributed to household contacts in the Philippines.

Data on the burden of disease from tuberculosis (TB) in Filipino households are limited. To determine the magnitude of undiagnosed TB in TB households, and the demographic and socio-economic factors associated with TB in the Philippines, household contacts of adult smear-positive TB patients seen from July 2001 to June 2003 were assessed based on interview, chest X-ray, tuberculin skin test and sputum examination. History of TB and older age were independently associated with TB disease, and age and duration of cohabitation with TB infection.

Cephalosporin MIC distribution of extended-spectrum-{beta}-lactamase- and pAmpC-producing Escherichia coli and Klebsiella species.

The acquisition of beta-lactamases in members of the Enterobacteriaceae family poses a challenge to antimicrobial susceptibility testing in the clinical laboratory. We correlated the distribution of the MICs for Klebsiella spp. and Escherichia coli with the presence of extended-spectrum beta-lactamase (ESBL) and plasmid-mediated AmpC beta-lactamase (pAmpC) genes.

Real-time PCR vs standard culture detection of group A beta-hemolytic streptococci at various anatomic sites in tonsillectomy patients.

Objective: To compare rates of group A beta-hemolytic streptococci (GABHS) detection by real-time polymerase chain reaction (rtPCR) and standard culture (SCx) at different anatomic sites to determine whether a more patient-friendly site (eg, retromolar trigone or gingivobuccal sulcus) would yield results similar to the tonsillar surface. Real-time polymerase chain reaction can detect GABHS at rates equal to SCx, and results require only a few hours.

Design: Prospective study.

Bivalvular Bartonella henselae prosthetic valve endocarditis.

Prosthetic valve endocarditis is an uncommon manifestation of infection with Bartonella species. Herein, we report a case of Bartonella henselae endocarditis involving prosthetic mitral and aortic valves. The patient had a favorable outcome with combined medical and surgical therapy.

Quantitative real-time polymerase chain reaction for evaluating DNAemia due to cytomegalovirus, Epstein-Barr virus, and BK virus in solid-organ transplant recipients.

Testing for cytomegalovirus-, Epstein-Barr virus-, and BK virus-specific gene targets in specimens from solid-organ transplant recipients for DNA by quantitative real-time polymerase chain reaction has been implemented in many diagnostic facilities. This technology provides rapid, accurate, and reproducible results for early detection, monitoring, and medical management of patients with these infections. Because these assays are becoming commonly used in clinical practice, the technical variables associated with specimen processing (e.

Sonication of removed hip and knee prostheses for diagnosis of infection.

Background: Culturing of samples of periprosthetic tissue is the standard method used for the microbiologic diagnosis of prosthetic-joint infection, but this method is neither sensitive nor specific. In prosthetic-joint infection, microorganisms are typically present in a biofilm on the surface of the prosthesis. We hypothesized that culturing of samples obtained from the prosthesis would improve the microbiologic diagnosis of prosthetic-joint infection.

Age- and sex-associated trends in bloodstream infection: a population-based study in Olmsted County, Minnesota.

Background: Despite increasing concerns about antimicrobial resistance and emerging pathogens among blood culture isolates, contemporary population-based data on the age- and sex-specific incidence of bloodstream infections (BSIs) are limited.

Methods: Retrospective, population-based, cohort study of all residents of Olmsted County, Minnesota, with a BSI between January 1, 2003, and December 31, 2005. The medical record linkage system of the Rochester Epidemiology Project and microbiology records were used to identify incident cases.

Fungi, mycobacteria, zoonotic and other organisms in prosthetic joint infection.

A systematic review of the presentation and management of prosthetic joint infection (PJI) due to zoonotic microorganisms, fungi, mycobacteria and other unusual microorganisms is not available. We therefore sought to provide a resource for the practicing orthopaedic surgeon which will serve as a guide for making appropriate decisions in managing such rare, but potentially problematic conditions. We conducted a Medline search of all case reports of PJI due to these unusual microorganisms.

Unusual aerobic and anaerobic bacteria associated with prosthetic joint infections.

The association of certain microorganisms, such as Staphylococcus epidermidis, Staphylococcus aureus, and beta-hemolytic streptococci, with prosthetic joint infection (PJI) has been recognized for many years. To our knowledge, a systematic review of the presentation and management of less commonly encountered species of coagulase-negative staphylococci, nutritional-variant streptococci, aerobic non-spore and spore forming Gram-positive or anaerobic bacteria is not available. We therefore sought to provide a comprehensive literature review of PJI due to these microorganisms that will provide a valuable and quick reference for clinicians caring for these patients.

Bronchoscopy in ventilator-associated pneumonia: agreement of calibrated loop and serial dilution.

Rationale: Although the serial dilution technique for quantitative culture of bronchoalveolar fluid is considered to be the gold standard for the diagnosis of ventilator-associated pneumonia, it is more labor intensive than the calibrated loop technique.

Objective: We sought to determine the agreement between the calibrated loop and serial dilution techniques in the diagnosis of ventilator-associated pneumonia.

Methods: We prospectively measured bacterial colony counts by the serial dilution and calibrated loop techniques in 121 bronchoalveolar lavage samples of 104 patients with suspected ventilator-associated pneumonia.

Sonication of explanted prosthetic components in bags for diagnosis of prosthetic joint infection is associated with risk of contamination.

Explanted orthopedic implants from 54 patients with aseptic failure and 24 patients with prosthetic knee or hip infection were sonicated in polyethylene bags. The sensitivities of periprosthetic tissue and sonicate fluid cultures for the diagnosis of prosthetic joint infection were 54% and 75%, whereas the specificities were 98% and 87%, respectively. Sonication in bags improved bacterial recovery from the surface of orthopedic implants; however, it lacked specificity, due to bag leakage.

Real-time PCR in clinical microbiology: applications for routine laboratory testing.

Real-time PCR has revolutionized the way clinical microbiology laboratories diagnose many human microbial infections. This testing method combines PCR chemistry with fluorescent probe detection of amplified product in the same reaction vessel. In general, both PCR and amplified product detection are completed in an hour or less, which is considerably faster than conventional PCR detection methods.