scholarly journals Multicenter Investigation of Gepotidacin (GSK2140944) Agar Dilution Quality Control Determinations for Neisseria gonorrhoeae ATCC 49226

2016 ◽  
Vol 60 (7) ◽  
pp. 4404-4406 ◽  
Author(s):  
Ronald N. Jones ◽  
Kelley A. Fedler ◽  
Nicole E. Scangarella-Oman ◽  
James E. Ross ◽  
Robert K. Flamm

ABSTRACTGepotidacin, a novel triazaacenaphthylene antibacterial agent, is the first in a new class of type IIA topoisomerase inhibitors with activity against many biothreat and conventional pathogens, includingNeisseria gonorrhoeae. To assist ongoing clinical studies of gepotidacin to treat gonorrhea, a multilaboratory quality assurance investigation determined the reference organism (N. gonorrhoeaeATCC 49226) quality control MIC range to be 0.25 to 1 μg/ml (88.8% of gepotidacin MIC results at the 0.5 μg/ml mode).

2018 ◽  
Vol 94 (7) ◽  
pp. 479-482 ◽  
Author(s):  
Pam Sawatzky ◽  
Irene Martin ◽  
Patricia Galarza ◽  
Marıa Elena Trigoso Carvallo ◽  
Pamela Araya Rodriguez ◽  
...  

ObjectivesA Neisseria gonorrhoeae antimicrobial susceptibility quality control comparison programme was re-established in Latin America and the Caribbean to ensure antimicrobial susceptibility data produced from the region are comparable nationally and internationally.MethodsThree panels, consisting of N. gonorrhoeae isolates comprising reference strains and other characterised isolates were sent to 11 participating laboratories between 2013 and 2015. Antimicrobial susceptibilities for these isolates were determined using agar dilution, Etest or disc diffusion methods. Modal minimum inhibitory concentrations (MICs) for each panel isolate/antibiotic combination were calculated. The guidelines of the Clinical and Laboratory Standards Institute were used for interpretations of antimicrobial susceptibility. The agreement of MICs with the modal MICs was determined for each of the participating laboratories as well as for each of the antibiotics tested.ResultsFive of 11 laboratories that participated in at least one panel had an overall average agreement between participants’ MIC results and modal MICs of >90%. For other laboratories, agreements ranged from 60.0% to 82.4%. The proportion of agreement between interpretations for all the antibiotics, except penicillin and tetracycline, was >90%. The percentages of agreement between MIC results and their modes for erythromycin, spectinomycin, cefixime and azithromycin were >90%. Tetracycline, ceftriaxone and ciprofloxacin agreement ranged from 84.5% to 89.1%, while penicillin had 78.8% agreement between MICs and modal MICs.ConclusionsThe participating laboratories had acceptable results, similar to other international quality assurance programmes. It is important to ensure continuation of the International Gonococcal Antimicrobial Susceptibility Quality Control Comparison Programme to ensure that participants can identify and correct any problems in antimicrobial susceptibility testing for N. gonorrhoeae as they arise and continue to generate reproducible and reliable data.


2015 ◽  
Vol 54 (3) ◽  
pp. 749-753 ◽  
Author(s):  
Maria M. Traczewski ◽  
Jennifer Deane ◽  
Daniel Sahm ◽  
Steven D. Brown ◽  
Laurent Chesnel

Test parameter variations were evaluated for their effects on surotomycin MICs. Calcium concentration was the only variable that influenced MICs; therefore, 50 μg/ml (standard for lipopeptide testing) is recommended. Quality control ranges forClostridium difficile(0.12 to 1 μg/ml) andEggerthella lenta(broth, 1 to 4 μg/ml; agar, 1 to 8 μg/ml) were approved by the Clinical and Laboratory Standards Institute based on these data.


2016 ◽  
Vol 54 (3) ◽  
pp. 805-808 ◽  
Author(s):  
P. Hemarajata ◽  
S. Yang ◽  
O. O. Soge ◽  
R. M. Humphries ◽  
J. D. Klausner

In the United States, 19.2% ofNeisseria gonorrhoeaeisolates are resistant to ciprofloxacin. We evaluated a real-time PCR assay to predict ciprofloxacin susceptibility using residual DNA from the Roche Cobas 4800 CT/NG assay. The results of the assay were 100% concordant with agar dilution susceptibility test results for 100 clinical isolates. Among 76 clinical urine and swab specimens positive forN. gonorrhoeaeby the Cobas assay, 71% could be genotyped. The test took 1.5 h to perform, allowing the physician to receive results in time to make informed clinical decisions.


2019 ◽  
Vol 32 (1) ◽  
pp. 84-86
Author(s):  
Sidra Asad Ali ◽  
Muhammad Shariq Shaikh

Purpose With recent advances in laboratory hematology automation, emphasis is now on quality assurance processes as they are indispensable for generating reliable and accurate test results. It is therefore imperative to acquire efficient measures for recognizing laboratory malfunctions and errors to improve patient safety. The paper aims to discuss these issues. Design/methodology/approach Moving algorithm is a quality control process that monitors analyzer performance from historical records through a continuous process, which does not require additional expenditure, and can serve as an additional support to the laboratory quality control program. Findings The authors describe an important quality assurance tool, which can be easily applied in any laboratory setting, especially in cost-constrained areas where running commercial controls throughout every shift may not be a feasible option. Originality/value The authors focus on clinical laboratory quality control measures for providing reliable test results. The moving average appears to be a reasonable and applicable choice for vigilantly monitoring each result.


2019 ◽  
Vol 57 (12) ◽  
Author(s):  
Gary N. McAuliffe ◽  
Marian Smith ◽  
Gavin Cooper ◽  
Rose F. Forster ◽  
Sally A. Roberts

ABSTRACT Azithromycin is a component of empirical treatment regimens for Neisseria gonorrhoeae infections, but antimicrobial susceptibility testing for this agent is technically challenging. We compared the intertest variability, MIC values, and CLSI/EUCAST categorization of clinical and reference isolates of N. gonorrhoeae treated with azithromycin by testing 107 clinical isolates and nine reference isolates by agar dilution and in duplicates using MIC test strips (Liofilchem, Italy) and Etests (bioMérieux, France). Replicate isolate agreement within 1 log2 between duplicate tests was 87% for MIC test strips and 100% for Etests (P < 0.001). Essential agreement with the agar dilution method was higher for Etests (91%) than for MIC test strips (44%, P < 0.001). The geometric mean MIC was highest for MIC test strips (0.8 mg/liter) and significantly higher than both Etest (0.47 mg/liter, P < 0.001) and agar dilution (0.26 mg/liter, P < 0.001) methods. Etest MICs were higher than those obtained with agar dilution (P < 0.001). Agar dilution, MIC test strip, and Etest methods categorized 96%, 85%, and 95% (P = 0.003) of clinical isolates, respectively, as susceptible/wild type according to CLSI/EUCAST criteria. Our results illustrate the difficulties underlying azithromycin susceptibility testing for N. gonorrhoeae and demonstrate that results can vary using different methods. This variability could influence antimicrobial resistance reporting between laboratories involved in N. gonorrhoeae surveillance programs.


2019 ◽  
Vol 63 (9) ◽  
Author(s):  
Yen-Hung Liu ◽  
Ya-Hui Wang ◽  
Chun-Hsing Liao ◽  
Po-Ren Hsueh

ABSTRACT A total of 598 Neisseria gonorrhoeae isolates obtained from patients in Taiwan from 2001 to 2018 were evaluated. The MICs of ceftriaxone (CRO) and azithromycin (AZM) against the isolates were determined by the agar dilution method. N. gonorrhoeae isolates with AZM MICs of ≥1 μg/ml were identified and characterized by the presence of AZM resistance determinants. For high-level AZM-resistant (AZM-HLR) isolates (MIC ≥ 256 μg/ml), genotyping was performed using multilocus sequence typing (MLST) and N. gonorrhoeae multiantigen sequence typing (NG-MAST). Among the N. gonorrhoeae isolates studied, 8.7% (52/598) exhibited AZM MICs of ≥1 μg/ml. Thirteen of the 52 isolates contained A2059G (23S rRNA NG-STAR type 1) or C2611T (23S rRNA NG-STAR type 2) mutations. The prevalence of the A2059G mutation was higher in AZM-HLR isolates (P < 0.001). The −35A deletion in the promoter region of the mtrR gene did not differ between AZM-HLR isolates (100%, 10/10) and the isolates with AZM MICs of 1 μg/ml to 64 μg/ml (95.2%, 40/42) (P = 1.000). The presence of mutations in the mtrR coding region was significantly different between these two groups at 90% (9/10) and 26.2% (11/42), respectively (P < 0.001). The AZM-HLR isolates, all carrying four mutated A2059G alleles, a −35A deletion, and G45D, were classified as MLST 12039/10899 and NG-MAST 1866/16497. In conclusion, Taiwan is among the countries reporting gonococci with high-level resistance to AZM so that a single dose of 1 g ceftriaxone intramuscularly as the first choice for management of N. gonorrhoeae infection should be evaluated.


2017 ◽  
Vol 55 (6) ◽  
pp. 1767-1777 ◽  
Author(s):  
L. M. Koeth ◽  
J. M. DiFranco-Fisher ◽  
N. E. Scangarella-Oman ◽  
L. A. Miller

ABSTRACTThis study was conducted to determine the effect of testing parameters on thein vitroactivity of gepotidacin, a new triazaacenaphthylene antibacterial agent for the treatment of conventional and biothreat pathogens. CLSI methods, and variations of those methods, were used to test 10Staphylococcus aureus, 10Streptococcus pneumoniae, 10Haemophilus influenzae, and 5Escherichia coliisolates by MIC and 30S. aureus, 15S. pneumoniae, and 15S. pyogenesisolates by disk diffusion (DD) methods. Levofloxacin and linezolid were tested as comparator agents for MIC and DD methods, respectively. Broth microdilution (BMD), macrodilution (MD), and agar dilution (AD) methods were compared. Variations in media, temperature, incubation time, CO2level, and inoculum concentration were tested by all methods, and variations in pH, calcium, magnesium, zinc, potassium, thymidine, and polysorbate 80 levels were tested by BMD and DD. The addition of albumin, serum, and lung surfactant was studied by BMD. The variables that impacted the results the most were high inoculum and pH 5.5 (no growth ofH. influenzaeandS. pneumoniaeby BMD). Gepotidacin AD MIC levels were increased and disk zone diameters were decreased for all species in 10% CO2incubation. The following variables had a minimal effect on gepotidacin results: pH, agar method, atmospheric condition, temperature, and addition of serum and albumin for broth methods. There were also some slight differences in gepotidacin disk results between disk manufacturers and some agar types and also with potassium and thymidine forS. pneumoniae. For all other variations, gepotidacin MIC and disk results were considered comparable to reference results.


2019 ◽  
Vol 57 (9) ◽  
Author(s):  
Alita A. Miller ◽  
Maria M. Traczewski ◽  
Michael D. Huband ◽  
Patricia A. Bradford ◽  
John P. Mueller

ABSTRACT This report describes the results of two different, multilaboratory quality control (QC) studies that were used to establish QC ranges for the novel gyrase inhibitor zoliflodacin against the ATCC strains recommended by the Clinical and Laboratory Standards Institute (CLSI). Following the completion of an eight-laboratory, CLSI document M23-defined tier 2 study, the agar dilution MIC QC range for zoliflodacin against the Neisseria gonorrhoeae QC strain ATCC 49226 was defined as 0.06 to 0.5 μg/ml and was approved by the CLSI Subcommittee on Antimicrobial Susceptibility Testing. This QC range will be used for in vitro susceptibility testing of zoliflodacin during phase 3 human clinical trials and surveillance studies, and eventually it will be implemented in clinical labs. In a separate study, broth microdilution MIC quality control ranges for zoliflodacin against additional QC strains were determined to be 0.12 to 0.5 μg/ml for Staphylococcus aureus ATCC 29213, 0.25 to 2 μg/ml for Enterococcus faecalis ATCC 29212, 1 to 4 μg/ml for Escherichia coli ATCC 25922, 0.12 to 0.5 μg/ml for Streptococcus pneumoniae ATCC 49619, and 0.12 to 1 μg/ml for Haemophilus influenzae ATCC 49247. These MIC QC ranges were also approved by CLSI for use in future in vitro susceptibility testing studies against organisms other than N. gonorrhoeae.


2018 ◽  
Vol 26 (2) ◽  
pp. 278-289
Author(s):  
Kristen Cibelli Hibben ◽  
Beth-Ellen Pennell ◽  
Lesli Scott

Purpose At the invitation of the Programme for the International Assessment of Adult Competencies (PIAAC), this paper aims to examine advances in survey interviewer monitoring and make recommendations on minimizing the effect of interviewers on survey results. Design/methodology/approach The authors first provide an overview of the most recent literature on interviewer effects, quality assurance and quality control. Here, they draw upon recent publications such as the cross-cultural survey guidelines (www.ccsg.isr.umich.edu) and newly published or in-press material specifically addressing these issues in multicultural, multinational and multiregional (3MC) contexts. Findings The authors discuss trends and innovations in quality assurance and quality control in 3MC studies and draw upon examples from international surveys that are using cutting-edge and innovative approaches to monitor interviewer behavior and minimize interviewer effects. Originality/value With a view to continuous quality improvement, the authors conclude with concrete recommendations for PIAAC to consider for the next cycle. Many of the recommendations have general relevance for other large-scale cross-national surveys.


2017 ◽  
Vol 34 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Philips Oluwaseun Ayeni ◽  
Niran Adetoro

Purpose The purpose of this paper is to examine perceived and factual realities of open access predators and further delve into usage patterns of predatory open access journals (OAJs) by researchers and its implication on quality assurance in Library and Information Science Research. It also investigates factors promoting use of these outlets, as well as authors’ perspectives on quality control for OAJs. Design/methodology/approach The paper reviewed available literature on OAJs and the proliferation of predatory journals. It also presents author’s viewpoint on the implication of using predatory journals for Library and Information Science Research in Nigeria. Findings The number of predatory publishers globally has grown rapidly from 18 in 2011 to 693 in 2015, whereas standalone journals increased from 126 to 507 in 2015. Library and information science (LIS) studies were published in some of the listed predatory journals by Jeffrey Beall, and this has reduced global recognition of LIS researchers in Nigeria. Upcoming authors were easily attracted to publishing their work in predatory journals because of fast review process, prompt publishing and quest for global visibility. Checking against plagiarism, ensuring quality control, increased awareness for non-use of predatory journals were some of the recommendations given. Practical implications It is clear that if LIS educators report their research in predatory OA outlets, individual and institutional reputation will be affected which may eventually lead to low ranking status of institutions. Nigerian universities low ranking status by several indices can be traced to the nonappearance or low scholarly literature published in reputable and respected journal outlets. Scholars with less quality studies will not be invited to feature as reviewers and international panelist in reputable thematic conferences and meetings neither can they be invited as external examiners in universities abroad. Originality/value This work is very valuable in evaluating the growth of predatory journals in Library and information Science Research in Nigeria. It provides distinctive ways to evaluating OAJs and how to identify and avoid predatory journals.


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