Publications by authors named "Deborah S Ashcraft"

was discovered in 2009 and has rapidly emerged as a serious public health threat with cases reported in over 20 countries worldwide. As of May 8, 2020, the Centers for Disease Control and Prevention reported a total of 1122 US cases. is often multidrug resistant, leaving few options for treatment.

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is a nosocomial pathogen containing various resistance mechanisms. Among them, metallo-β-lactamase (MBL)-producing are difficult to treat. Fosfomycin is an older antibiotic that has recently seen increased usage due to its activity against a broad spectrum of multidrug-resistant organisms.

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Acinetobacter baumannii is an opportunistic pathogen predominantly associated with nosocomial infections. The World Health Organization's data on antibiotic-resistant 'priority pathogens' reports carbapenem-resistant A. baumannii as a pathogen which is in critical need of research and development of new antimicrobials.

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Candida species, traditionally viewed as opportunistic agents, are increasingly seen as a cause of infection in hospitalized patients. Treatment options are limited to a few classes of drugs. Increased resistance, especially by Candida glabrata, is problematic.

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Background: Candida species account for most invasive fungal infections, and the emergence of fluconazole and caspofungin resistance is problematic. Overcoming resistance with synergism between 2 drugs may be useful. In a 2013 in vitro study, caspofungin plus colistin (polymyxin E) was found to act synergistically against fluconazole-resistant and susceptible Candida albicans isolates.

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Two linezolid-resistant Enterococcus faecium isolates (MICs, 8 μg/ml) from unique patients of a medical center in New Orleans were included in this study. Isolates were initially investigated for the presence of mutations in the V domain of 23S rRNA genes and L3, L4, and L22 ribosomal proteins, as well as cfr. Isolates were subjected to pulsed-field gel electrophoresis (just one band difference), and one representative strain was submitted to whole-genome sequencing.

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Increasing global antibiotic resistance has resulted in more use of antibiotic combinations. There is a lack of a gold standard for in vitro testing of these combinations for synergy or antagonism. Time-kill assay (TKA) may be used but is labor intensive and not practical for clinical use.

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Background: An emerging pathogen is Enterococcus faecium resistant to both linezolid and vancomycin (LRVRE). Antimicrobial combinations may be required for therapy and need to be evaluated. The combination of daptomycin and rifampin has demonstrated good in vitro activity against gram-positive bacteria, including E faecium.

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Polymyxin B (PB) plus meropenem (MER) or rifampin (RIF) was tested by Etest® method and time-kill assay (TKA) against 14 genetically unique clinical Klebsiella pneumoniae carbapenemase-producing K. pneumoniae. PB + MER: Etest, 43% synergy; TKA, 64% synergy.

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Synergy testing of levofloxacin and meropenem by Etest and time-kill assay (TKA) was performed against 30 genetically unique clinical Stenotrophomonas maltophilia isolates. Synergy was demonstrated in 18/30 (60%) isolates by Etest and in 13/30 (43%) by TKA; the remaining isolates were indifferent. Methods showed agreement for 25/30 (83%) of isolates.

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This time-kill study was performed with 65 genetically unique clinical isolates of Gram-negative bacilli and enterococci to further define the antibacterial activity of tigecycline. To our knowledge, this is the largest published time-kill study evaluating tigecycline activity to date. Isolates evaluated were 10 meropenem-resistant Acinetobacter baumannii; 15 Escherichia coli, including 10 extended-spectrum beta-lactamase (ESBL) producers; 15 Klebsiella pneumoniae, including 10 ESBL producers; 20 vancomycin-resistant Enterococcus faecium (VRE), including 10 that were linezolid resistant; and 5 vancomycin-susceptible Enterococcus faecalis.

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Time-kill assay and Etest testing for synergy of meropenem (MER) (1x MIC) plus polymyxin B (1/4, 1/2, and 1x MIC) were performed against 8 genetically unique MER-resistant clinical Acinetobacter baumannii isolates. Time-kill assay demonstrated synergy for all isolates, whereas Etest showed synergy in 5 isolates and indifference in 3.

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Objective: To test for synergy between daptomycin (DAP) and rifampin (RIF) against RIF-resistant methicillin-resistant Staphylococcus aureus (MRSA) isolates.

Methods: Synergy testing using time-kill assay (TKA) was performed on 6 clinically, and genetically unique RIF-resistant MRSA isolates. The isolates were identified out of 489 (1.

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Multidrug-resistant Pseudomonas aeruginosa with combined decreased susceptibility to ceftazidime, ciprofloxacin, imipenem, and piperacillin is increasingly being found as a cause of nosocomial infections. It is important to look for combinations of drugs that might be synergistic. Ciprofloxacin resistance by P.

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