Relationship between results of in vitro susceptibility tests and outcomes following treatment with pirlimycin hydrochloride in cows with subclinical mastitis associated with gram-positive pathogens

2009 ◽  
Vol 234 (11) ◽  
pp. 1437-1446 ◽  
Author(s):  
Dhananjay Apparao ◽  
Leane Oliveira ◽  
Pamela L. Ruegg
Keyword(s):  
Subclinical Mastitis ◽  
Gram Positive ◽  
In Vitro Susceptibility ◽  
Susceptibility Tests

scholarly journals Genes conferring anti­microbial resistance in cattle with subclinical mastitis

2021 ◽  
Vol 24 (1) ◽  
pp. 67-85
Author(s):  
N. H. Youssif ◽  
N. M. Hafiz ◽  
M. A. Halawa ◽  
H. M. Aziz
Keyword(s):  
Resistance Genes ◽  
Methicillin Resistance ◽  
Subclinical Mastitis ◽  
Cow Milk ◽  
In Vitro Susceptibility ◽  
Milk Samples ◽  
Dairy Animals ◽  
Susceptibility Tests ◽  
Moderate Resistance

This study was carried out to evaluate the antimicrobial resistance (AMR) as a risk factor associated with some microorganisms isolated from subclinical mastitis (SCM) milk samples from Holstein Friesian dairy animals in Fayoum area, Egypt. The percentage of the SCM in the farm was found to be 41.18% and 63.88% at quarter and cows level respectively, with mean somatic cell count (SCC) of 8.8×105 ± 9.2×103 cells/mL and electrical conductivity (EC) 6.27 ± 0.066 mS/cm for SCM quarter milk samples. Out of the total 444 SCM cow milk samples, the most often isolated microorganisms were Staphylococcus aureus: 296 (66.6%), Enterococcus spp.: 230 (51.80%), Escherichia coli: 210 (47.29%) and Streptococcus agalactiae: 106 (23.87%). AMR was determined by disc diffusion test and the corresponding resistance genes were detected by PCR. Results of the in vitro susceptibility tests performed and the phenotypes indicated that the highest resistance to antibiotics for isolated microorganisms was against penicillin followed by amoxicillin + clavulanic acid, oxacillin and tetracycline, whereas moderate resistance was exhibited to oxytetracycline, ampicillin, sulfamethazole/trimethoprim, cefotaxime and erythromycin. However the most effective antibiotics against most isolates were nitrofurantoin and gentamicin followed by enrofloxacin, norfloxacin and cefoxitin. It was shown that the resistance to tetracyclines was due to the tetK or tetA(A) genes, the resistance to β-lactams (penicillins) – to blaZ and blaTEM genes, to macrolides (erythromycin): to ermB and ermC genes. Methicillin resistance genes were mecA, mec1 and mecC, glycopeptides (vancomycin) resistance gene was vanA, and norfloxacin resistance was attributed to norA gene.

scholarly journals In Vitro Activities of Three Nonfluorinated Quinolones against Representative Bacterial Isolates

2001 ◽  
Vol 45 (6) ◽  
pp. 1923-1927 ◽  
Author(s):  
Arthur L. Barry ◽  
Peter C. Fuchs ◽  
Steven D. Brown
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Bacterial Isolates ◽  
Gram Positive ◽  
In Vitro Susceptibility ◽  
Gram Negative ◽  
Methicillin Resistant ◽  
Inhibitory Activities ◽  
Susceptibility Tests

ABSTRACT In vitro susceptibility tests were performed to document the inhibitory activities of three nonfluorinated quinolone (NFQ) compounds (PGE 9262932, PGE 9509924, and PGE 4175997) compared to those of ciprofloxacin, levofloxacin, and trovafloxacin against 3,030 bacterial isolates. The spectra of the NFQ agents included most gram-positive species as well as quinolone-susceptibleEnterobacteriaceae. Ciprofloxacin-resistant, methicillin-resistant Staphylococcus aureus strains were inhibited by the NFQ series at ≤1.0 μg/ml. The NFQ compounds were not very active against Pseudomonas aeruginosa and most other nonfermentative gram-negative bacilli. Against other species, the potency of the NFQ agents was similar to that of trovafloxacin. Continued investigation of the NFQ compounds seems to be warranted.

Prolonged Pneumococcal Meningitis Due to an Organism With Increased Resistance to Penicillin

PEDIATRICS ◽  
1976 ◽  
Vol 58 (3) ◽  
pp. 378-381 ◽  
Author(s):  
Abel Paredes ◽  
Larry H. Taber ◽  
Martha D. Yow ◽  
Dorothy Clark ◽  
William Nathan
Keyword(s):  
Case Report ◽  
Streptococcus Pneumoniae ◽  
Pneumococcal Meningitis ◽  
Pneumococcal Infections ◽  
In Vitro Susceptibility ◽  
Focus Of Infection ◽  
Resistance To Penicillin ◽  
Penicillin Treatment ◽  
Susceptibility Tests

For more than 30 years, penicillin has been the agent of choice for pneumococcal infections. During this time the majority of strains of Streptococcus pneumoniae have been highly susceptible to penicillin. However, during the last ten years there have been sporadic reports of pneumococci with increased resistance to penicillin. The case report of an 18-month-old white boy with meningitis due to a strain of S. pneumoniae with increased resistance to penicillin is presented. The MIC of the organism to penicillin was 0.2µg/ml and the MBC 0.39µg/ml. The patient had normal immunity and no demonstrable sequestered focus of infection but failed to respond to appropriate doses of intravenous penicillin. Treatment with chloramphenicol caused a dramatic bacteriologic and clinical response. This experience reemphasizes the existence of pneumococcal strains of intermediate penicillin sensitivity and the importance of in vitro susceptibility tests.

Assessment of Laboratory Performance With Streptococcus pneumoniae Antimicrobial Susceptibility Testing in the United States

1999 ◽  
Vol 123 (4) ◽  
pp. 285-289 ◽  
Author(s):  
Gary V. Doern ◽  
Angela B. Brueggemann ◽  
Michael A. Pfaller ◽  
Ronald N. Jones
Keyword(s):  
United States ◽  
Streptococcus Pneumoniae ◽  
Antimicrobial Agents ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
The United States ◽  
National Committee ◽  
In Vitro Susceptibility ◽  
Susceptibility Tests

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.

LABORATORY ASPECTS OF ANTIBIOTIC THERAPY

PEDIATRICS ◽  
1951 ◽  
Vol 8 (3) ◽  
pp. 406-412
Author(s):  
EARLE H. SPAULDING
Keyword(s):  
Antibiotic Therapy ◽  
Single Species ◽  
Clinical Results ◽  
Bacterial Strains ◽  
In Vitro Susceptibility ◽  
Bacterial Cultures ◽  
Susceptibility Tests ◽  
And Control ◽  
Susceptibility Patterns

Bacterial strains within a single species exhibit highly specific susceptibility patterns when tested with the several antibiotics currently available. Because in vitro susceptibility tests constitute the only certain method for predicting clinical response, the bacteriology laboratory is playing an expanding part in the choice and control of antibiotic therapy. Although there is no need for bacteriologic studies in the vast majority of infections, they are sometimes essential to the successful management of severe acute, refractory and relapsing infections. The correlation between laboratory and clinical results is good providing allowances are made for certain factors discussed in this paper. Antibiotic susceptibility tests are entirely practical and should be used routinely in all laboratories which do bacterial cultures.

scholarly journals In Vitro Susceptibility of Mycobacterium abscessus and Mycobacterium fortuitum Isolates to 30 Antibiotics

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yaojie Shen ◽  
Xuyang Wang ◽  
Jialin Jin ◽  
Jing Wu ◽  
Xuelian Zhang ◽  
...  
Keyword(s):  
Public Health Problem ◽  
Drug Susceptibility ◽  
Mycobacterium Abscessus ◽  
Mycobacterium Fortuitum ◽  
In Vitro Susceptibility ◽  
Antitubercular Drugs ◽  
Microdilution Method ◽  
Susceptibility Tests ◽  
Susceptibility Profiles

Objective. Nontuberculous mycobacteria (NTM) cause various diseases in humans and animals. Recently, the prevalence of NTM-related disease has been on the rise, becoming an emerging public health problem. The aim of this study was to determine the antibiotic susceptibility profiles of clinical isolates of Mycobacterium abscessus and Mycobacterium fortuitum. Methods. We performed susceptibility tests on 37 clinical NTM isolates to 30 antibiotics with the microdilution method recommended by the Clinical and Laboratory Standards Institute. Results. Both M. abscessus and M. fortuitum were highly resistant to antitubercular drugs such as isoniazid, rifampin, ethambutol, clofazimine, ethionamide, and rifabutin. M. abscessus showed the lowest resistant rates to cefoxitin (10%), azithromycin (10%), amikacin (10%), and clarithromycin (20%) and very high resistant to sulfamethoxazole, vancomycin, oxacillin, clindamycin, and all fluoroquinolones. M. fortuitum showed low resistance to tigecycline (0%), tetracycline (0%), cefmetazole (12%), imipenem (12%), linezolid (18%), and the aminoglycosides amikacin (0%), tobramycin (0%), neomycin (0%), and gentamycin (24%). Conclusion. Amikacin, cefoxitin, and azithromycin have the highest in vitro activity against M. abscessus. Isolates of M. fortuitum need to be individually evaluated for drug susceptibility before choosing an effective antimicrobial regimen for treatment of infections.

Meropenem: A New Carbapenem Antimicrobial

1994 ◽  
Vol 28 (9) ◽  
pp. 1045-1054 ◽  
Author(s):  
Randy D. Pryka ◽  
George M. Haig
Keyword(s):  
Clinical Trials ◽  
English Language ◽  
Antimicrobial Agents ◽  
Pharmacokinetic Analysis ◽  
Upper Respiratory Tract ◽  
Gram Positive ◽  
Scientific Publications ◽  
In Vitro Susceptibility ◽  
Study Selection

OBJECTIVE: To describe and then compare an investigational carbapenem antibiotic, meropenem, with the only currently available antibiotic in this class, imipenem/cilastatin. DATA IDENTIFICATION: An English language search using MEDLINE (1988–1993); Abstracts of the 31st Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), 1991; and Abstracts of the 32nd ICAAC, 1992. STUDY SELECTION: All current scientific publications were reviewed for study design and quality. Emphasis was placed on susceptibility and pharmacokinetic analysis. Phase 3 clinical trials are now being completed and have only been published in abstract form. Hence, conclusions derived regarding efficacy were tempered. RESULTS: Meropenem is active against a broad spectrum of gram-positive and -negative pathogens including beta-lactamase producers. Meropenem appears to be two- to fourfold less active than imipenem against gram-positive organisms. Meropenem is two- to fivefold more active against enterobacteriaceae. The two compounds appear to be equally active against Pseudomonas aeruginosa. Pharmacokinetic disposition is also similar for imipenem and meropenem. Meropenem may exhibit greater tissue penetration. Meropenem is not labile to renal hydrolysis and can be administered without a competitive antagonist of dihydropeptidase, such as cilastatin. In clinical trials, meropenem appears to be as safe and effective as imipenem/cilastatin or ceftazidime in the treatment of infections involving soft tissue, urinary tract, upper respiratory tract, abdominal processes, and febrile neutropenic episodes. CONCLUSIONS: Meropenem is comparable to imipenem in terms of in vitro susceptibility pattern and pharmacokinetic disposition. Overall, meropenem seems to offer promise as the second of the carbapenem class of antibiotics. Clinical data are preliminary, and further data are needed.

In vitro Susceptibility to Everninomycin of Gram-Positive Nosocomial Pathogens Isolated from Intensive Care Units in Germany

Chemotherapy ◽  
2000 ◽  
Vol 47 (1) ◽  
pp. 15-18 ◽  
Author(s):  
Andrea Kropec ◽  
Andrea Kropec ◽  
Uwe Frank ◽  
Uwe Frank ◽  
Daniel Jonas ◽  
...  
Keyword(s):  
Intensive Care ◽  
Intensive Care Units ◽  
Gram Positive ◽  
In Vitro Susceptibility ◽  
Nosocomial Pathogens

scholarly journals Effect of fluconazole on viability of Candida albicans over extended periods of time.

1996 ◽  
Vol 40 (11) ◽  
pp. 2622-2625 ◽  
Author(s):  
P G Sohnle ◽  
B L Hahn ◽  
M D Erdmann
Keyword(s):  
Candida Albicans ◽  
Marked Reduction ◽  
Culture Medium ◽  
Antimicrobial Agents ◽  
Yeast Cells ◽  
In Vitro Susceptibility ◽  
Fungistatic Activity ◽  
Susceptibility Tests ◽  
Infecting Organisms

The treatment of chronic mycoses may expose the infecting organisms to antimicrobial agents for extended periods of time. It is possible that an azole antifungal drug such as fluconazole, with primarily fungistatic activity in standard in vitro susceptibility tests, might be able to damage the fungal cells and reduce their viability over prolonged incubations under nonproliferating conditions. To test this possibility, Candida albicans yeast cells were exposed to various concentrations of fluconazole in RPMI 1640 tissue culture medium for 4 h at 37 degrees C, washed free of the drug, and then incubated at 37 degrees C for a 28-day period; enumeration of the remaining CFU at various times during this period revealed no increased loss of viability for the fluconazole-exposed organisms. However, when fluconazole was added to the organisms maintained in distilled water (with or without pretreatment with the drug), a marked reduction of viability was found. At 14 days of incubation with two strains of C. albicans, negative cultures were found for 7 of 10 and 10 of 11 samples, respectively, containing 1.0 microgram of fluconazole per ml versus 0 of 10 and 1 of 11 control samples (P of < 0.01 and 0.001, respectively). The effect of fluconazole on fungal viability under these conditions became noticeable at approximately 7 days and was greater when the samples were incubated at 37 degrees C rather than 25 degrees C. These findings suggest that fluconazole may have fungicidal effects on fungal cells during prolonged exposures under conditions in which the organisms are prevented from proliferating by lack of nutrients.

Sign in / Sign up

Export Citation Format

Share Document