scholarly journals A ten-year (2000–2009) study of antimicrobial susceptibility of bacteria that cause bovine respiratory disease complex—Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni—in the United States and Canada

2012 ◽  
Vol 24 (5) ◽  
pp. 932-944 ◽  
Author(s):  
Ellen Portis ◽  
Cynthia Lindeman ◽  
Lacie Johansen ◽  
Gillian Stoltman

Bovine isolates of Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni, collected from 2000 to 2009, were tested for in vitro susceptibility to ceftiofur, penicillin, danofloxacin, enrofloxacin, florfenicol, tetracycline, tilmicosin, and tulathromycin. Ceftiofur remained very active against all isolates. Penicillin retained good activity against P. multocida and H. somni isolates with no appreciable changes in susceptibility or minimal inhibitory concentration (MIC) distributions with time. While there was no obvious trend, the percent of M. haemolytica that were susceptible to penicillin ranged from 40.9% to 66.7%. Danofloxacin MIC50 and MIC90 values for M. haemolytica and P. multocida did not change beyond a single dilution over the 6 years it was included in the testing panel. The MIC90 for H. somni increased beyond 1 dilution. Enrofloxacin MIC50 values for the 3 pathogens also did not change over time, unlike the MIC90 values, which increased by at least 4-doubling dilutions. Ninety percent or more of M. haemolytica and H. somni isolates were susceptible to florfenicol, while susceptibility among P. multocida was 79% or greater. Less than 50% of the isolates tested as susceptible to tetracycline in many of the years. All 3 organisms showed declines in tilmicosin and tulathromycin MIC50 and MIC90 values over the years in which they were tested.

2019 ◽  
Vol 15 (02) ◽  
pp. 22-25
Author(s):  
Sunaina Thakur ◽  
Subhash Verma ◽  
Prasenjit Dhar ◽  
Mandeep Sharma

Respiratory infections of sheep and goats cause heavy morbidity and mortality, leading to huge economic losses. Conventional methods of diagnosis that include isolation and identification of incriminating microbes are time-consuming and fraught with logistic challenges. Direct detection of incriminating microbes using molecular tools is gaining popularity in clinical, microbiological settings. In this study, a total of 50 samples (44 nasal swabs and 6 lung tissues) from sheep and goats were screened for the detection of different bacterial species by in vitro amplification of genus or species-specific genes. Histophilus somni was detected in 2% goat samples, Trueperella pyogenes in 20% goat nasal swabs, whereas 22% goat nasal swab samples were found positive for Mycoplasma spp. None of the samples from sheep was detected positive for H. somni, T. pyogenes, Mycoplasma spp. Similarly, all samples, irrespective, whether from sheep or goats, showed negative results for Pasteurella multocida, Mannheimia haemolytica, and Corynebacterium pseudotuberculosis.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S733-S733
Author(s):  
Dee Shorttidge ◽  
Jennifer M Streit ◽  
Michael D Huband ◽  
Robert K Flamm

Abstract Background Delafloxacin (DLX) is an anionic fluoroquinolone (FQ) that has been approved in the United States and in Europe for the treatment of acute bacterial skin and skin structure infections and was recently approved in the US for treatment of community-acquired bacterial pneumonia (CABP). In the present study, in vitro susceptibility (S) results for DLX and comparator agents were determined for CABP pathogens including Streptococcus pneumoniae (SPN), Haemophilus influenzae (HI), H. parainfluenzae (HP) and Moraxella catarrhalis (MC) clinical isolates from European hospitals participating in the SENTRY Program during 2014-2019. Methods A total of 2,835 SPN, 1,484 HI, 959 MC, and 20 HP isolates were collected from community-acquired respiratory tract infections (CARTI) during 2014-2019 from European hospitals. Sites included only 1 isolate/patient/infection episode. Isolate identifications were confirmed at JMI Laboratories. Susceptibility testing was performed according to CLSI broth microdilution methodology, and EUCAST (2020) breakpoints were applied where applicable. Other antimicrobials tested included levofloxacin (LEV) and moxifloxacin (MOX; not tested in 2015). Multidrug-resistant (MDR) SPN isolates were categorized as being nonsusceptible (NS) to amoxicillin-clavulanate, erythromycin (ERY), and tetracycline; other SPN phenotypes were ERY-NS, or penicillin (PEN)-NS. β-lactamase (BL) presence was determined for HI, HP, and MC. Results The activities of the 3 FQs are shown in the table. The most active agent against SPN was DLX, with the lowest MIC50/90 values of 0.015/0.03 mg/L. DLX activities were the same when tested against the MDR or PEN-NS for SPN phenotypes. ERY-NS isolates had DLX MIC50/90 results of 0.015/0.03 mg/L. DLX was the most active FQ against HI, HP, and MC. BL presence did not affect FQ MIC values for HI or MC; only 1 HP isolate was BL-positive. Conclusion DLX demonstrated potent in vitro antibacterial activity against SPN, HI, HP, and MC. DLX was active against MDR SPN that were NS to the agents commonly used as treatments for CABP. These data support the utility of DLX in CABP including when caused by antibiotic resistant strains. Table 1 Disclosures Jennifer M. Streit, BS, A. Menarini Industrie Farmaceutiche Riunite S.R.L. (Research Grant or Support)A. Menarini Industrie Farmaceutiche Riunite S.R.L. (Research Grant or Support)Allergan (Research Grant or Support)Melinta Therapeutics, Inc. (Research Grant or Support)Melinta Therapeutics, Inc. (Research Grant or Support)Melinta Therapeutics, Inc. (Research Grant or Support)Merck (Research Grant or Support)Paratek Pharma, LLC (Research Grant or Support) Robert K. Flamm, PhD, A. Menarini Industrie Farmaceutiche Riunite S.R.L. (Research Grant or Support)Amplyx Pharmaceuticals (Research Grant or Support)Basilea Pharmaceutica International, Ltd (Research Grant or Support)Department of Health and Human Services (Research Grant or Support)Melinta Therapeutics, Inc. (Research Grant or Support)


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S793-S793
Author(s):  
Lynn-Yao Lin ◽  
Dmitri Debabov ◽  
William Chang

Abstract Background OXA-48 is a carbapenemase with low-level hydrolytic activity toward cephalosporins. This study evaluated in vitro activities of ceftazidime-avibactam (CAZ-AVI), meropenem (MEM), meropenem-vaborbactam (MVB), ceftolozane-tazobactam (C/T), and other antimicrobial agents against 113 OXA-48-producing Enterobacterales with multiple resistance mechanisms collected in a 2017–2018 global surveillance program. Methods Nonduplicate clinical isolates of 113 Enterobacterales were collected from medical centers in 25 countries in 2017–2018. In vitro susceptibility tests were performed by broth microdilution with a custom-made panel consisting of CAZ-AVI, ceftazidime (CAZ), MEM, MVB, C/T, colistin (COL), gentamicin (GEN), levofloxacin (LEV), and amikacin (AMK). Whole genome sequencing or quantitative PCR data were used to analyze resistance mechanisms, such as OXA-48, extended-spectrum β-lactamase (ESBL), original-spectrum β-lactamase (OSBL), and AmpC β-lactamase. Clinical and Laboratory Standards Institute breakpoints were applied for susceptibility interpretations. Results Of 113 OXA-48–producing clinical isolates, 20 carried OXA-48 alone. The remaining 93 isolates carried additional β-lactamases, including 63 with ESBL (CTX-M-15) + OSBL (SHV, TEM), 15 with AmpC (DHA, AAC, CMY) + ESBL (CTX-M-15), and 15 with OSBL (SHV, TEM). 99.1% (all but 1) of all isolates tested were susceptible to CAZ-AVI, whereas 71.7%, 17.7%, and 14.2% were susceptible to MVB, MEM, and C/T, respectively. Among isolates harboring multiple resistance mechanisms (OXA-48 + ESBL + OSBL; n=63), 98.4%, 69.8%, 11.1%, and 7.9% were susceptible to CAZ-AVI, MVB, MEM, and C/T, respectively. Among isolates carrying OXA-48 + AmpC + ESBL + OSBL (n=15), 100%, 66.7%, 13.3%, and 13.3% were susceptible to CAZ-AVI, MVB, MEM, and C/T, respectively (Table). Aminoglycosides (AMK and GEN) and other β-lactams (eg, CAZ) were 20%–90% active against these isolates. COL was the second most effective comparator, inhibiting 83.2% of these isolates. Table Conclusion CAZ-AVI was the most effective agent in this study compared with other antibiotics, including β-lactams, β-lactam–β-lactamase inhibitor combinations, aminoglycosides, and COL, against OXA-48-producing Enterobacterales carrying multiple β-lactamases. Disclosures Lynn-Yao Lin, MS, AbbVie (Employee) Dmitri Debabov, PhD, AbbVie (Employee) William Chang, BS, AbbVie (Employee)


1999 ◽  
Vol 123 (4) ◽  
pp. 285-289 ◽  
Author(s):  
Gary V. Doern ◽  
Angela B. Brueggemann ◽  
Michael A. Pfaller ◽  
Ronald N. Jones

Abstract Objective.—To assess the performance of clinical microbiology laboratories in the United States when conducting in vitro susceptibility tests with Streptococcus pneumoniae. Methods.—The results of a nationwide College of American Pathologists Proficiency Survey test sample, in which susceptibility testing of an isolate of S pneumoniae was performed, were assessed with respect to precision and accuracy. Results.—Wide variability was noted among participating laboratories with both minimum inhibitory concentration procedures and disk diffusion susceptibility tests when both methods were applied to S pneumoniae. Despite this high degree of variation, categorical interpretive errors were uncommon. Numerous laboratories reported results for antimicrobial agents that are not recommended by the National Committee for Clinical Laboratory Standards for tests with S pneumoniae. Conclusions.—Current susceptibility testing practices with S pneumoniae in the United States indicate limited precision and a tendency for laboratories to test and report results obtained with antimicrobial agents of questionable therapeutic value against this organism. Continued efforts to standardize susceptibility testing of S pneumoniae in the United States are warranted. In addition, modifications of existing interpretive criteria may be necessary.


1997 ◽  
Vol 119 (2) ◽  
pp. 175-181 ◽  
Author(s):  
Y. HIRAKATA ◽  
T. YAMAGUCHI ◽  
K. IZUMIKAWA ◽  
J. MATSUDA ◽  
K. TOMONO ◽  
...  

Glycopeptide resistance in enterococci is now a cause of clinical concern in the United States and Europe. However, details of vancomycin resistance in enterococci in Japan have been unknown. We measured minimum inhibitory concentrations (MICs) of various antimicrobial agents for a total of 218 clinical strains of enterococci isolated in our hospital in 1995–6 in addition to 15 strains with known genotypic markers of resistance. We also screened vancomycin resistance genes using a single step multiplex-PCR.In clinical isolates, only two strains of Enterococcus gallinarum were of intermediate resistance to vancomycin (MIC, 8 μg/ml), while the others were all susceptible. Glycopeptides (vancomycin and teicoplanin) and streptogramins (RP 58500 and RPR 106972) showed potent antimicrobial effects for the isolates. In addition, ampicillin was also potent for Enterococcus faecalis, while ampicillin, minocycline and gentamicin were potent for Enterococcus avium. No vanA or vanB genes were detected, while vanC1 and vanC23 genes were detected from two and four strains, respectively. Our results suggest that incidence of VRE in Japan may be estimated as still very low at this time.


Author(s):  
Jade L. L. Teng ◽  
Elaine Chan ◽  
Asher C. H. Dai ◽  
Gillian Ng ◽  
Tsz Tuen Li ◽  
...  

Both typhoidal and non-typhoidal salmonellae are included in the top 15 drug-resistant threats described by the Center for Disease Control and Prevention of the United States. There is an urgent need to look for alternative antibiotics for the treatment of Salmonella infections. We examined the in vitro susceptibilities of ceftolozane/tazobactam and six other antibiotics on typhoidal and non-typhoidal salmonellae, including isolates that are extended-spectrum β-lactamase (ESBL)-positive, using the broth microdilution test. Of the 313 (52 typhoidal and 261 non-typhoidal) Salmonella isolates tested, 98.7% were susceptible to ceftolozane/tazobactam. Based on the overall MIC 50/90 values, Salmonella isolates were more susceptible to ceftolozane/tazobactam (0.25/0.5 mg/L) compared to all other comparator agents: ampicillin (≥64/≥64 mg/L), levofloxacin (0.25/1 mg/L), azithromycin (4/16 mg/L), ceftriaxone (≤0.25/4 mg/L), chloramphenicol (8/≥64 mg/L) and trimethoprim/sulfamethoxazole (1/≥8 mg/L). When comparing the activity of the antimicrobial agents against non-typhoidal Salmonella isolates according to their serogroup, ceftolozane/tazobactam had the highest activity (100%) against Salmonella serogroups D, G, I and Q isolates, whereas the lowest activity (85.7%) was observed against serogroup E isolates. All the 10 ESBL-producing Salmonella (all non-typhoidal) isolates, of which 8 were CTX-M-55-producers and 2 were CTX-M-65-producers, were sensitive to ceftolozane/tazobactam albeit with a higher MIC 50/90 value (1/2 mg/L) than non-ESBL-producers (0.25/0.5 mg/L). In summary, our data indicate that ceftolozane/tazobactam is active against most strains of both typhoidal and non-typhoidal salmonellae and also active against ESBL-producing salmonellae.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S577-S578
Author(s):  
Dee Shortridge ◽  
Jennifer M Streit ◽  
Michael D Huband ◽  
Robert K Flamm

Abstract Background Delafloxacin (DLX) is an anionic fluoroquinolone (FQ) antimicrobial that was approved in 2017 by the United States (US) Food and Drug Administration for the treatment of acute bacterial skin and skin structure infections. DLX recently successfully completed a clinical trial for the treatment of community-acquired bacterial pneumonia (CABP). In the present study, in vitro susceptibility (S) results for DLX and comparator agents were determined for CABP pathogens including Streptococcus pneumoniae (SPN), Haemophilus influenzae (HI), H. parainfluenzae (HP) and Moraxella catarrhalis (MC) clinical isolates from US hospitals participating in the SENTRY Program during 2014–2018. Methods A total of 1,975 SPN, 1,128 HI, 684 MC, and 43 HP isolates were collected from community-acquired respiratory tract infections (CARTI) during 2014–2018 from US hospitals. Sites included only 1 isolate/patient/infection episode. Isolate identifications were confirmed at JMI Laboratories. Susceptibility testing was performed according to CLSI broth microdilution methodology, and CLSI (2019) breakpoints were applied where applicable. Other antimicrobials tested included levofloxacin (LEV) and moxifloxacin (MOX; not tested in 2015). Multidrug-resistant (MDR) SPN isolates were categorized as being nonsusceptible (NS) to amoxicillin-clavulanate, erythromycin, and tetracycline; other SPN phenotypes were LEV-NS or penicillin (PEN)-NS. β-Lactamase (BL) presence was determined for HI, HP, and MC. Results The activities of the 3 FQs are shown in the table. The most active agent against SPN was DLX, with the lowest MIC50/90 values of 0.015/0.03 mg/L. DLX activities were similar when tested against the MDR or PEN-NS for SPN phenotypes. LEV-NS isolates had DLX MIC50/90 results of 0.12/0.25 mg/L. DLX was the most active FQ against HI, HP, and MC. BL presence did not affect FQ MIC values for HI or MC; only 2 HP isolates were BL-positive. Conclusion DLX demonstrated potent in vitro antibacterial activity against SPN, HI, HP, and MC. DLX was active against MDR SPN that were NS to the agents commonly used as treatments for CABP. DLX had excellent activity against LEV-NS SPN. These data support the continued study of DLX as a potential treatment for CABP. Disclosures All authors: No reported disclosures.


Sign in / Sign up

Export Citation Format

Share Document