Direct molecular detection of amoxicillin-susceptible in urine samples from children with suspected urinary tract infection: A potential tool to improve antibiotic stewardship and patient care.

Background: Rapid detection of amoxicillin-susceptible (ASEC) urinary tract infections (UTIs) could have a significant impact on patient care and improve antibiotic stewardship. This is especially true for infants and children, for whom antibiotic choices are more limited than for adults.

Methods: A real-time polymerase chain reaction (PCR) uniplex panel for detection of ASEC using PCR assays for and five resistance genes ( , , , , and ) and an internal control was designed.

Contemporary Microbiology and Antimicrobial Treatment of Complicated Appendicitis: The Value of a Short-term Study.

Background: Antimicrobial stewardship interventions to curtail the use of third-generation cephalosporins and antipseudomonal penicillins for the treatment of complicated appendicitis in children are challenging given the tendency to treat complicated disease with broad-spectrum antimicrobials. Reasons for this are unclear, but there is a paucity of contemporary microbiologic data associated with the child presenting with either acute perforated or gangrenous appendicitis. This study aimed to justify the appropriateness of an empiric regimen consisting of ampicillin, tobramycin/gentamicin plus metronidazole and to analyze duration of postoperative therapy.

Incidental post-partum isolation of in an asymptomatic woman.

A 25-year-old Somali-born female was admitted to the hospital in active labour. Following post-partum hemorrhage, grew from a blood culture and the placenta. Identification and relatedness were determined through reverse transcriptase polymerase chain reaction (RT-PCR), single nucleotide polymorphism (SNP), and whole genome sequencing.

A comparison of the Allplex™ bacterial and viral assays to conventional methods for detection of gastroenteritis agents.

Objective: Molecular methods to detect diarrheal pathogens are increasingly being used in place of conventional methods. We compared a new multiplex real-time PCR assay for detection of both bacterial and viral gastroenteritis agents, the Allplex™ Gastrointestinal Panel Assays (AGPA), to conventional methods (stool culture for bacterial pathogens and electron microscopy (EM) for viral pathogens).

Results: Gastrointestinal viruses, in particular norovirus genogroup II viruses, were detected by the AGPA in a high number of specimens that were negative by EM.

Clostridium difficile: Investigating Transmission Patterns Between Infected and Colonized Patients Using Whole Genome Sequencing.

Background: Whole genome sequencing (WGS) studies can enhance our understanding of the role of patients with asymptomatic Clostridium difficile colonization in transmission.

Methods: Isolates obtained from patients with Clostridium difficile infection (CDI) and colonization identified in a study conducted during 2006-2007 at 6 Canadian hospitals underwent typing by pulsed-field gel electrophoresis, multilocus sequence typing, and WGS. Isolates from incident CDI cases not in the initial study were also sequenced where possible.

Outcomes in a nurse-led peripherally inserted central catheter program: a retrospective cohort study.

Background: Peripherally inserted central catheters (PICCs) provide enormous benefit to patients. However, recent publications have highlighted relatively high PICC-associated complication rates. We report on patient and device outcomes from a nurse-led program.

Pneumocystis pneumonia outbreak among renal transplant recipients at a North American transplant center: Risk factors and implications for infection control.

Background: Pneumocystis pneumonia is a severe opportunistic fungal infection. Outbreaks among renal transplant recipients have been reported in Europe and Japan, but never in North America.

Methods: We conducted a retrospective case-control study among adult renal transplant recipients at a Canadian center, using a 3:1 matching scheme.

Risk Factors for and Outcomes of Bacteremia Caused by Extended-Spectrum ß-Lactamase-Producing Escherichia coli and Klebsiella Species at a Canadian Tertiary Care Hospital.

Background: Antimicrobial resistance due to production of extended-spectrum ß-lactamases by Escherichia coli and Klebsiella species (ESBL-EK) is concerning. Previous studies have shown that bacteremia due to ESBL-producing organisms is associated with increases in length of stay and/or mortality rate. Rates of infection by ESBL-EK vary worldwide, and regional differences in the prevalence of risk factors are likely.

Disseminated histoplasmosis associated with acquired hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a potentially life-threatening clinical syndrome caused by uncontrolled activation of lymphocytes and histiocytes resulting in high levels of cytokines. Acquired HLH occurs in autoimmune, inflammatory, infectious, and immunosuppressive disorders. Prompt identification and treatment of an underlying triggering cause improves clinical outcome.

Predictors of asymptomatic Clostridium difficile colonization on hospital admission.

Background: Clostridium difficile (CD) is the leading cause of health care-associated diarrhea and can result in asymptomatic carriage. Rates of asymptomatic CD colonization on hospital admission range from 1.4%-21%.

Antimicrobial susceptibility of clinical isolates of anaerobic bacteria in Ontario, 2010-2011.

The local epidemiology of antimicrobial susceptibility patterns in anaerobic bacteria is important in guiding the empiric treatment of infections. However, susceptibility data are very limited on anaerobic organisms, particularly among non-Bacteroides organisms. To determine susceptibility profiles of clinically-significant anaerobic bacteria in Ontario Canada, anaerobic isolates from sterile sites submitted to Public Health Ontario Laboratory (PHOL) for identification and susceptibility testing were included in this study.

Characterization of methicillin-resistant Staphylococcus aureus isolates from patients with persistent or recurrent bacteremia.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSI) are associated with considerable morbidity and mortality, especially with persistent (PB) or recurrent bacteremia (RB).

Objective: To determine the frequency of PB and RB in patients with MRSA BSI, and to characterize the isolates from these patients.

Methods: Surveillance for MRSA BSI was performed for one year in 13 Canadian hospitals.

Linezolid resistance in Enterococcus faecium isolated in Ontario, Canada.

Recent studies have described linezolid-resistant MRSA and vancomycin-resistant enterococci (VRE) occurring worldwide, including an outbreak of linezolid-resistant MRSA. The objective of this study was to determine if linezolid-resistant enterococci are present in clinical isolates in Ontario, Canada. From January 2010 to June 2012, all enterococcal isolates submitted to the Public Health Ontario Laboratory (PHOL) for confirmation of VRE and susceptibility testing were included in this study.

Antimicrobial susceptibilities of clinical isolates of HACEK organisms.

The "HACEK" organisms are a group of fastidious Gram-negative bacteria that cause a variety of infections, including infective endocarditis. Antimicrobial susceptibility testing is not universally available, and therapy for these infections is often empirical. We report the antimicrobial susceptibilities of 70 clinical HACEK isolates to 18 antimicrobials.

A 7-year retrospective review from 2005 to 2011 of Propionibacterium acnes shoulder infections in Ottawa, Ontario, Canada.

This study evaluated the clinical factors associated with Propionibacterium acnes shoulder infection and the standard culture procedures for isolating P. acnes from shoulder specimens by a 7-year retrospective analysis. P.

Skin and soft tissue infections caused by methicillin-resistant Staphylococcus aureus (MRSA): an affliction of the underclass.

Objective: The objective of this study was to determine whether skin and soft tissue infections (SSTIs) caused by methicillin-resistant Staphylococcus aureus (MRSA) in patients presenting to The Ottawa Hospital emergency departments (TOHEDs) differed from SSTIs caused by methicillin-susceptible Staphylococcus aureus (MSSA) with regard to risk factors, management, and outcomes.

Methods: All patients seen at TOHEDs in 2006 and 2007 with SSTIs who yielded MRSA or MSSA in cultures from the site of infection were eligible for inclusion. We excluded patients with decubitus ulcers and infections related to diabetes or peripheral vascular disease.

Direct mecA polymerase chain reaction testing of blood culture bottles growing Gram-positive cocci and the clinical potential in optimizing antibiotic therapy for staphylococcal bacteremia.

This study evaluated the performance of direct mecA polymerase chain reaction (PCR) from blood culture bottles growing Gram-positive cocci in clusters and its role in optimization of antibiotic therapy. A total of 266 blood cultures including 121 methicillin-resistant and 122 methicillin-susceptible Staphylococci were tested for mecA. Compared to phenotypic testing, the overall performance of direct mecA PCR was 99% for sensitivity, specificity, positive predictive value, and negative predictive value, respectively.

The use of intravenous antibiotics at the onset of neutropenia in patients receiving outpatient-based hematopoietic stem cell transplants.

Empirical antibiotics at the onset of febrile neutropenia are one of several strategies for management of bacterial infections in patients undergoing Hematopoietic Stem Cell Transplant (HSCT) (empiric strategy). Our HSCT program aims to perform HSCT in an outpatient setting, where an empiric antibiotic strategy was employed. HSCT recipients began receiving intravenous antibiotics at the onset of neutropenia in the absence of fever as part of our institutional policy from 01 Jan 2009; intravenous Prophylactic strategy.

Evaluation of the sterility testing process of hematopoietic stem cells at Canadian Blood Services.

Background: Sterility testing of hematopoietic stem cells (HSCs) at The Canadian Blood Services Stem Cell Laboratory is performed using BacT/ALERT aerobic (SA) culture bottles. This study was conducted to verify the efficacy of this method and to assess the use of the BacT/ALERT aerobic (BPA) and anaerobic (BPN) culture bottles for microbial testing of HSCs.

Study Design And Methods: HSC products, including cryopreserved apheresis peripheral blood, marrow, and cord blood and fresh cord blood, were spiked with four aerobic organisms including Staphylococcus epidermidis, Bacillus cereus, Pseudomonas aeruginosa, and Candida albicans, and the anaerobe Bacteroides fragilis at a target concentration of 100 colony-forming units (CFUs)/mL.

Host and pathogen factors for Clostridium difficile infection and colonization.

Background: Clostridium difficile infection is the leading cause of health care-associated diarrhea, and the bacterium can also be carried asymptomatically. The objective of this study was to identify host and bacterial factors associated with health care-associated acquisition of C. difficile infection and colonization.