Advanced search    

Search: authors:"Barry N. Kreiswirth"

38 papers found.
Use AND, OR, NOT, +word, -word, "long phrase", (parentheses) to fine-tune your search.

Identification of Outer Membrane and Exoproteins of Carbapenem-Resistant Multilocus Sequence Type 258 Klebsiella pneumoniae

Carbapenem-resistant Klebsiella pneumoniae strains have emerged as a cause of life-threatening infections in susceptible individuals (e.g., transplant recipients and critically ill patients). Strains classified as multilocus sequence type (ST) 258 are among the most prominent causes of carbapenem-resistant K. pneumoniae infections worldwide, but the basis for the success of this ...

MRSA Clonal Complex 22 Strains Harboring Toxic Shock Syndrome Toxin (TSST-1) Are Endemic in the Primary Hospital in Gaza, Palestine

Background Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in both community and healthcare-related settings worldwide. Current knowledge regarding the epidemiology of S. aureus and MRSA in Gaza is based on a single community-based carriage study. Here we describe a cross-sectional analysis of 215 clinical isolates collected from Al-Shifa Hospital in ...

Rapid Molecular Diagnostics, Antibiotic Treatment Decisions, and Developing Approaches to Inform Empiric Therapy: PRIMERS I and II

Background. Rapid molecular diagnostic (RMD) platforms may lead to better antibiotic use. Our objective was to develop analytical strategies to enhance the interpretation of RMDs for clinicians. Methods. We compared the performance characteristics of 4 RMD platforms for detecting resistance against β-lactams in 72 highly resistant isolates of Escherichia coli and Klebsiella ...

Carbapenem-Resistant Klebsiella pneumoniae Exhibit Variability in Capsular Polysaccharide and Capsule Associated Virulence Traits

Background. Novel therapies are urgently needed to treat carbapenem-resistant Klebsiella pneumoniae (CR-Kp)-mediated infection, which constitute a major health threat in the United States. In order to assess if it is feasible to develop anticapsular antibodies as a potential novel therapy, it is crucial to first systematically characterize capsular polysaccharide (CPS) and ...

Production of an Attenuated Phenol-Soluble Modulin Variant Unique to the MRSA Clonal Complex 30 Increases Severity of Bloodstream Infection

. Duong Anthony J. Yeh Trung V. Ho Yan Chen Hwang-Soo Joo Barry N. Kreiswirth Andreas Peschel Michael Otto Alice Prince, Columbia University, United States of America Methicillin-resistant Staphylococcus

Extended Spectrum Beta-Lactamase-Producing Enterobacteriaceae in International Travelers and Non-Travelers in New York City

Background We performed this study 1) to determine the prevalence of community-associated extended spectrum beta-lactamase producing Enterobacteriaceae (ESBLPE) colonization and infection in New York City (NYC); 2) to determine the prevalence of newly-acquired ESBLPE during travel; 3) to look for similarilties in contemporaneous hospital-associated bloodstream ESBLPE and ...

Active Case Finding and Prevention of Tuberculosis Among a Cohort of Contacts Exposed to Infectious Tuberculosis Cases in New York City

Background. Tuberculosis contact investigation identifies individuals who may be recently infected with tuberculosis and are thus at increased risk for disease. Contacts with latent tuberculosis infection (LTBI) are offered chemoprophylaxis to prevent active disease; however, the effectiveness of this intervention is unclear as treatment completion is generally low. Methods. A ...

Lipoarabinomannan in urine during tuberculosis treatment: association with host and pathogen factors and mycobacteriuria

Background Detection of lipoarabinomannan (LAM), a Mycobacterium tuberculosis (Mtb) cell wall antigen, is a potentially attractive diagnostic. However, the LAM-ELISA assay has demonstrated variable sensitivity in diagnosing TB in diverse clinical populations. We therefore explored pathogen and host factors potentially impacting LAM detection. Methods LAM-ELISA assay testing, sputum ...

Distribution and Regulation of the Mobile Genetic Element-Encoded Phenol-Soluble Modulin PSM-mec in Methicillin-Resistant Staphylococcus aureus

The phenol-soluble modulin PSM-mec is the only known staphylococcal toxin that is encoded on a mobile antibiotic resistance determinant, namely the staphylococcal cassette chromosome (SCC) element mec encoding resistance to methicillin. Here we show that the psm-mec gene is found frequently among methicillin-resistant Staphylococcus aureus (MRSA) strains of SCCmec types II, III, ...

Emergence of Daptomycin Resistance in Daptomycin-Naïve Rabbits with Methicillin-Resistant Staphylococcus aureus Prosthetic Joint Infection Is Associated with Resistance to Host Defense Cationic Peptides and mprF Polymorphisms

Background Previous studies of both clinically-derived and in vitro passage-derived daptomycin–resistant (DAP-R) Staphylococcus aureus strains demonstrated the coincident emergence of increased DAP MICs and resistance to host defense cationic peptides (HDP-R). Methods In the present investigation, we studied a parental DAP-susceptible (DAP-S) methicillin-resistant Staphylococcus ...

Antibacterial Resistance Leadership Group: Open for Business

Funded by the National Institute of Allergy and Infectious Diseases, the Antibacterial Resistance Leadership Group (ARLG) is tasked with developing a clinical research agenda and conducting clinical studies to address the growing public health threat of antibacterial resistance. The ARLG has identified 4 high-priority areas of research: infections caused by gram-negative bacteria, ...

Nosocomial Transmission of Extensively Drug-Resistant Tuberculosis in a Rural Hospital in South Africa

Barry N. Kreiswirth 6 Barun Mathema 6 Elena Shashkina 6 Richard Rothenberg 5 Anthony P. Moll 4 Gerald Friedland 3 A. Willem Sturm 0 N. Sarita Shah 2 0 Department of Infection Prevention and Control

Nasal Carriage as a Source of agr-Defective Staphylococcus aureus Bacteremia

Inactivating mutations in the Staphylococcus aureus virulence regulator agr are associated with worse outcomes in bacteremic patients. However, whether agr dysfunction is primarily a cause or a consequence of early bacteremia is unknown. Analysis of 158 paired S. aureus clones from blood and nasal carriage sites in individual patients revealed that recovery of an agr-defective ...

Prevalence of agr Dysfunction among Colonizing Staphylococcus aureus Strains

Mutations in the staphylococcal virulence regulator gene agr frequently occur during Staphylococcus aureus infection. Whether agr-defective strains are fit for colonization, an important prerequisite for infection, is unknown. Screening by means of assays to detect δ-hemolysin activity and agr autoinducing peptide production indicated that 15 (~9%) of 160 healthy human subjects ...

Enhanced Expression of dltABCD Is Associated with the Development of Daptomycin Nonsusceptibility in a Clinical Endocarditis Isolate of Staphylococcus aureus

Using isogenic clinical bloodstream Staphylococcus aureus strains from a patient with relapsing endocarditis, we investigated the transcriptional profiles of the mprF and dlt genes in the context of cell-surface charge and daptomycin nonsusceptibility. As in prior studies, a point mutation within mprF was observed in the daptomycin-nonsusceptible strain. However, neither the ...

Epidemiologic Consequences of Microvariation in Mycobacterium tuberculosis

Background. Evidence from genotype-phenotype studies suggests that genetic diversity in pathogens have clinically relevant manifestations that can impact outcome of infection and epidemiologic success. We studied 5 closely related Mycobacterium tuberculosis strains that collectively caused extensive disease (n = 862), particularly among US-born tuberculosis patients. Methods. ...

Mutations in agr Do Not Persist in Natural Populations of Methicillin-Resistant Staphylococcus aureus

Staphylococcus aureus organisms vary in the function of the staphylococcal virulence regulator gene agr. To test for a relationship between agr and transmission in S. aureus, we determined the prevalence and genetic basis of agr dysfunction among nosocomial methicillin-resistant S. aureus (MRSA) in an area of MRSA endemicity. Identical inactivating agr mutations were not detected ...

Phenotypic and Genotypic Characteristics of Persistent Methicillin-Resistant Staphylococcus aureus Bacteremia In Vitro and in an Experimental Endocarditis Model

Background. Persistent MRSA bacteremia (PB) represents an important subset of Staphylococcus aureus infections and correlates with poor clinical outcomes. Methods. We profiled relevant in vitro phenotypic and genotypic characteristics of MRSA isolates from 39 persons with bacteremia (21 had PB and 18 had resolving bacteremia [RB]). We also compared the intrinsic virulence and ...