In vitro assessment of effect of initial specimen diversion device on detection of central venous catheter contamination or colonization.

The role of initial specimen diversion devices (ISDDs) in preventing contamination of central venous catheter (CVC) blood cultures is undefined. A model to simulate CVC colonization and contamination compared standard cultures with ISDD technique. ISDD detected 100% of colonized CVCs while decreasing false-positive cultures from 36% to 16%.

Regulatory dynamics of arginine metabolism in Staphylococcus aureus.

Staphylococcus aureus is a highly significant pathogen with several well studied and defined virulence factors. However, the metabolic pathways that are required to facilitate infection are not well described. Previous data have documented that S.

The genotypic antibiogram: using gram-negative antimicrobial resistance genes identified via rapid blood culture identification tests to optimize treatment of Enterobacterales bloodstream infections.

The negative predictive value of on BCID2 for ceftriaxone resistance in and group was 97% and 94%, respectively. Creation of a genotypic antibiogram led to updated local guidance for clinicians to utilize for empiric treatment of Enterobacterales bloodstream infections identified via rapid diagnostics.

Missed Opportunities for HIV Confirmatory Testing Using an Institutional Testing Algorithm Without Reflex to HIV Nucleic Acid Testing.

At our medical center, HIV nucleic acid tests are recommended when the HIV antigen-antibody screening immunoassay and antibody differentiation tests are discordant, but not done reflexively. A retrospective chart review found that 35% of discordant test results did not have HIV nucleic acid test completed as recommended.

bacteremia: A case report.

species are a group of obligated anaerobic gram-positive bacilli that are recognized as commensals of the gastrointestinal tract flora. Cases of bacteremia mediated by are rare. This report describes a case of bacteremia caused by in an 82-year-old female with a history of a cecal perforation secondary to an obstructing sigmoid stricture.

Microbiota and metabolic adaptation shape virulence and antimicrobial resistance during intestinal colonization.

Depletion of microbiota increases susceptibility to gastrointestinal colonization and subsequent infection by opportunistic pathogens such as methicillin-resistant (MRSA). How the absence of gut microbiota impacts the evolution of MRSA is unknown. The present report used germ-free mice to investigate the evolutionary dynamics of MRSA in the absence of gut microbiota.

Staphylococcus aureus skin colonization is mediated by SasG lectin variation.

Staphylococcus aureus causes the majority of skin and soft tissue infections, but this pathogen only transiently colonizes healthy skin. However, this transient skin exposure enables S. aureus to transition to infection.

Glutamatedependent arginine biosynthesis requires the inactivation of , and in .

Genome sequencing has demonstrated that encodes arginine biosynthetic genes synthesizing proteins that mediate arginine biosynthesis using glutamate as a substrate. Paradoxically, however, does not grow in a defined, glutamate-replete medium lacking arginine and glucose (CDM-R). Studies from our laboratory have found that specific mutations are selected by that facilitate growth in CDM-R.

skin colonization is mediated by SasG lectin variation.

causes the majority of skin and soft tissue infections, but this pathogen only transiently colonizes healthy skin. However, this transient skin exposure enables to transition to infection. Initial adhesion of to skin corneocytes is mediated by surface protein G (SasG).

Rise of the (possible) resistance: a review of susceptibility patterns for nontyphoidal in Nebraska.

Our institution sought to evaluate our antimicrobial stewardship empiric treatment recommendations for . Results from 36 isolates demonstrated reduced susceptibilities to fluoroquinolones with 1 isolate susceptible only to ceftriaxone. Analysis supports the current recommendation of empiric ceftriaxone therapy for severe infection and updated recommendation for sulfamethoxazole-trimethoprim in non-severe infections.

A critical role for staphylococcal nitric oxide synthase in controlling flavohemoglobin toxicity.

Most coagulase-negative staphylococcal species, including the opportunistic pathogen Staphylococcus epidermidis, struggle to maintain redox homeostasis and grow under nitrosative stress. Under these conditions, growth can only resume once nitric oxide (NO) is detoxified by the flavohemoglobin Hmp. Paradoxically, S.

Molecular characterization of causing disease among children in Nigeria during the introduction of PCV10 (GSK).

() is a leading vaccine-preventable cause of childhood invasive disease. Nigeria has the second highest pneumococcal disease burden globally, with an estimated ~49 000 child deaths caused by pneumococcal infections each year. Ten-valent pneumococcal conjugate vaccine (GSK; PCV10) was introduced in December 2014 in a phased approach.

Metabolic reprogramming and altered cell envelope characteristics in a pentose phosphate pathway mutant increases MRSA resistance to β-lactam antibiotics.

Central metabolic pathways control virulence and antibiotic resistance, and constitute potential targets for antibacterial drugs. In Staphylococcus aureus the role of the pentose phosphate pathway (PPP) remains largely unexplored. Mutation of the 6-phosphogluconolactonase gene pgl, which encodes the only non-essential enzyme in the oxidative phase of the PPP, significantly increased MRSA resistance to β-lactam antibiotics, particularly in chemically defined media with physiologically-relevant concentrations of glucose, and reduced oxacillin (OX)-induced lysis.

Disinfection of vascular catheter connectors that are protected by antiseptic caps is unnecessary.

Objective: Determination of whether vascular catheter disinfecting antiseptic-containing caps alone are effective at decreasing microbial colonization of connectors compared to antiseptic-containing caps plus a 5-second alcohol manual disinfection.

Setting: The study was conducted in a 718-bed, tertiary-care, academic hospital.

Patients: A convenience sample of adult patients across intensive care units and acute care wards with peripheral and central venous catheters covered with antiseptic-containing caps.

The Challenge of Emerging Resistant Gram-Positive Pathogens in Hip and Knee Periprosthetic Joint Infections.

➤: An increase in resistant bacterial pathogens has occurred over the last 4 decades.

➤: Careful patient selection and improving or correcting risk factors for periprosthetic joint infection (PJI) before elective surgical treatment are strongly recommended.

➤: Appropriate microbiological methods, including those used to detect and grow Cutibacterium acnes, are recommended.

A Transducing Bacteriophage Infecting Staphylococcus epidermidis Contributes to the Expansion of a Novel Siphovirus Genus and Implies the Genus Is Inappropriate for Phage Therapy.

The effort to discover novel phages infecting Staphylococcus epidermidis contributes to both the development of phage therapy and the expansion of genome-based phage phylogeny. Here, we report the genome of an S. epidermidis-infecting phage, Lacachita, and compare its genome with those of five other phages with high sequence identity.

60-year-old male with rapidly progressive pneumocephalus caused by Clostridium septicum in the setting of an occult colonic adenocarcinoma.

Background: Disseminated Clostridium septicum infection is an uncommon complication associated with malignancies, particular colonic adenocarcinoma. The organism appears to preferentially colonize large masses in rare individuals and subsequently seed the blood via mucosal ulceration. This has rarely been reported to lead to central nervous system infection and, in several cases, rapidly progressive pneumocephalus.

Metabolic reprogramming and flux to cell envelope precursors in a pentose phosphate pathway mutant increases MRSA resistance to β-lactam antibiotics.

Unlabelled: Central metabolic pathways controls virulence and antibiotic resistance, and constitute potential targets for antibacterial drugs. In the role of the pentose phosphate pathway (PPP) remains largely unexplored. Mutation of the 6-phosphogluconolactonase gene which encodes the only non-essential enzyme in the oxidative phase of the PPP, significantly increased MRSA resistance to β-lactam antibiotics, particularly in chemically defined media with glucose, and reduced oxacillin (OX)-induced lysis.

Mechanistic basis of staphylococcal interspecies competition for skin colonization.

Staphylococci, whether beneficial commensals or pathogens, often colonize human skin, potentially leading to competition for the same niche. In this multidisciplinary study we investigate the structure, binding specificity, and mechanism of adhesion of the Aap lectin domain required for skin colonization and compare its characteristics to the lectin domain from the orthologous adhesin SasG. The Aap structure reveals a legume lectin-like fold with atypical architecture, showing specificity for N-acetyllactosamine and sialyllactosamine.

The staphylococcal biofilm protein Aap mediates cell-cell adhesion through mechanically distinct homophilic and lectin interactions.

The accumulation phase of staphylococcal biofilms relies on both the production of an extracellular polysaccharide matrix and the expression of bacterial surface proteins. A prototypical example of such adhesive proteins is the long multidomain protein Aap (accumulation-associated protein) from , which mediates zinc-dependent homophilic interactions between Aap B-repeat regions through molecular forces that have not been investigated yet. Here, we unravel the remarkable mechanical strength of single Aap-Aap homophilic bonds between living bacteria and we demonstrate that intercellular adhesion also involves sugar binding through the lectin domain of the Aap A region.

Proline transporters ProT and PutP are required for Staphylococcus aureus infection.

Proline acquired via specific transporters can serve as a proteinogenic substrate, carbon and nitrogen source, or osmolyte. Previous reports have documented that Staphylococcus aureus, a major community and nosocomial pathogen, encodes at least four proline transporters, PutP, OpuC, OpuD, and ProP. A combination of genetic approaches and 3H-proline transport assays reveal that a previously unrecognized transporter, ProT, in addition to PutP, are the major proline transporters in S.

Staphylococcal Corneocyte Adhesion: Assay Optimization and Roles of Aap and SasG Adhesins in the Establishment of Healthy Skin Colonization.

Staphylococcus aureus is an opportunistic pathogen that causes the majority of wound and soft tissue infections. The accumulation-associated protein (Aap) from S. epidermidis and surface protein G (SasG) from S.

Neuroinvasive West Nile virus infections after solid organ transplantation: Single center experience and systematic review.

Unlabelled: West Nile virus (WNv) is a major cause of viral encephalitis in the United States. WNv infection is usually asymptomatic or a limited febrile illness in the immunocompetent hosts, although a small percentage can develop neuroinvasive disease. Neuroinvasive disease due to WNv in solid organ transplant recipients occurs at higher rates than observed in the general population and can have long term neurological sequalae.

Catabolic Ornithine Carbamoyltransferase Activity Facilitates Growth of Staphylococcus aureus in Defined Medium Lacking Glucose and Arginine.

Previous studies have found that arginine biosynthesis in Staphylococcus aureus is repressed via carbon catabolite repression (CcpA), and proline is used as a precursor. Unexpectedly, however, robust growth of S. aureus is not observed in complete defined medium lacking both glucose and arginine (CDM-R).