ABSTRACT GSK1322322 is a novel peptide deformylase inhibitor in the early phase of development for treatment of complicated bacterial skin and skin structure infection and hospitalized community-acquired pneumonia. This quality control (QC) study was performed to establish broth microdilution and disk diffusion QC ranges for strains Staphylococcus aureus ATCC 29213 (MIC range, 1 to 4 μg/ml), Haemophilus influenzae ATCC 49247 (MIC and disk diffusion zone diameter ranges, 0.5 to 4 μg/ml and 20 to 28 mm, respectively), Streptococcus pneumoniae ATCC 49619 (MIC and disk diffusion zone diameter ranges, 0.12 to 0.5 μg/ml and 23 to 30 mm, respectively), and S. aureus ATCC 25923 (disk diffusion zone diameter range, 18 to 26 mm). These ranges are crucial for evaluating GSK1322322 potency as it progresses through clinical trials.
Abstract The performance of antimicrobial susceptibility tests (ASTs) to help guide patient therapy is one of the most important functions of a clinical microbiology laboratory. The most commonly used AST methods to date can be categorized into dilution methods that generate minimum inhibitory concentration values and disk diffusion methods that generate a zone diameter result. Most clinical microbiology laboratories in the United States and in many developed countries utilize manual or automated commercial dilution products that provide AST results which are demonstrated to correspond to the International Organization for Standardization/Clinical and Laboratory Standards Institute broth microdilution reference method. This chapter provides descriptions, context, advantages, and disadvantages for each of the methods: broth microdilution, broth macrodilution, agar dilution, and disk diffusion. The convenience afforded by the availability of sterile microdilution trays with round or conical bottoms for use in dilution susceptibility testing led to the widespread use of broth microdilution methods.
Journal Article Evaluation of Two Commercially Available Test Methods to Determine the Feasibility of Testing for Respiratory Syncytial Virus in a Community Hospital Laboratory Get access Julie M. White, M.S., Julie M. White, M.S. The Bryn Mawr Hospital, Bryn Mawr, The Medical College of Pennsylvania, Philadelphia, and Holy Redeemer Hospital, Meadowbrook, Pennsylvania Address reprint requests to Ms. White: 2363 Mole Road, Secane, Pennsylvania 19018. Search for other works by this author on: Oxford Academic Google Scholar James A. Poupard, Ph.D., James A. Poupard, Ph.D. The Bryn Mawr Hospital, Bryn Mawr, The Medical College of Pennsylvania, Philadelphia, and Holy Redeemer Hospital, Meadowbrook, Pennsylvania Search for other works by this author on: Oxford Academic Google Scholar Ralph A. Knight, Ph.D., Ralph A. Knight, Ph.D. The Bryn Mawr Hospital, Bryn Mawr, The Medical College of Pennsylvania, Philadelphia, and Holy Redeemer Hospital, Meadowbrook, Pennsylvania Search for other works by this author on: Oxford Academic Google Scholar Linda A. Miller, Ph.D. Linda A. Miller, Ph.D. The Bryn Mawr Hospital, Bryn Mawr, The Medical College of Pennsylvania, Philadelphia, and Holy Redeemer Hospital, Meadowbrook, Pennsylvania Search for other works by this author on: Oxford Academic Google Scholar American Journal of Clinical Pathology, Volume 90, Issue 2, 1 August 1988, Pages 175–180, https://doi.org/10.1093/ajcp/90.2.175 Published: 01 August 1988 Article history Received: 29 June 1987 Accepted: 10 February 1988 Published: 01 August 1988
We evaluated microbiological correlates for the successful treatment of Neisseria gonorrhoeae isolates from a phase 2 study of gepotidacin, a novel triazaacenaphthylene antibacterial, for therapy of uncomplicated urogenital gonorrhea. Culture, susceptibility testing, genotypic characterization, and frequency of resistance (FoR) were performed for selected isolates.
ABSTRACT Determining the genetic characteristics of Staphylococcus aureus is important for better understanding of the global and dynamic epidemiology of this organism as we witness the emergence and spread of virulent and antibiotic-resistant clones. We genotyped 292 S. aureus isolates (105 methicillin resistant and 187 methicillin susceptible) using a combination of pulsed-field gel electrophoresis, multilocus sequence typing, and SCC mec typing. In addition, S. aureus isolates were tested for the presence of the Panton-Valentine leukocidin (PVL) genes. Isolates were recovered from patients with uncomplicated skin infections in 10 different countries during five phase III global clinical trials of retapamulin, a new topical antibiotic agent. The most common methicillin-resistant clone had multilocus sequence type 8, pulsed-field type USA300, and SCC mec type IV and possessed the PVL genes. This clone was isolated exclusively in the United States. The most common PVL-positive, methicillin-susceptible clone had multilocus sequence type 121 and pulsed-field type USA1200. This clone was found primarily in South Africa and the Russian Federation. Other clones were found at lower frequencies and were limited in their geographic distribution. Overall, considerable genetic diversity was observed within multilocus sequence type clonal complexes and pulsed-field types.
ABSTRACT From 1997 to 1999, 94 study centers in 15 European, 3 North American, and 2 South American countries contributed 2,632 isolates of Streptococcus pneumoniae to an international antimicrobial susceptibility testing study. Only 62.0% of isolates were susceptible to penicillin, while 22.3% were penicillin intermediate and 15.6% were penicillin resistant. Resistance to trimethoprim-sulfamethoxazole (24.4%), azithromycin (26.0%), and clarithromycin (27.1%) was also highly prevalent. For the penicillin-resistant isolates ( n = 411), the MICs at which 90% of isolates are inhibited (MIC 90 s) for gemifloxacin, levofloxacin, ofloxacin, clarithromycin, and azithromycin were 0.03, 1, 2, >16, and >64 μg/ml, respectively. Similarly, for isolates resistant to both azithromycin and clarithromycin ( n = 649), gemifloxacin, levofloxacin, ofloxacin, and penicillin MIC 90 s were 0.03, 1, 2, and 4 μg/ml, respectively. Overall rates of resistance to trovafloxacin (0.3%), levofloxacin (0.3%), grepafloxacin (0.6%), and ofloxacin (0.7%) were low. For ofloxacin-intermediate and -resistant isolates ( n = 142), gemifloxacin had the lowest MIC 90 (0.12 μg/ml) compared to the MIC 90 s of trovafloxacin (0.5 μg/ml), grepafloxacin (1 μg/ml), and levofloxacin (2 μg/ml). For all S. pneumoniae isolates tested, gemifloxacin MICs were ≤0.5 μg/ml, suggesting that gemifloxacin has the potential to be used as a treatment for pneumococcal infections, including those arising from isolates resistant to β-lactams and macrolides.
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)