Comparative Minimal Inhibitory and Mutant Prevention Concentration of Eight Antimicrobial Agents Against Klebsiella pneumoniae

2021 ◽  
Author(s):  
Fan Yang ◽  
Ping Chen ◽  
Huiyuan Wang ◽  
Xiaoyu Xing ◽  
Sisi Wang ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Antimicrobial Agents ◽  
Mutant Prevention Concentration

scholarly journals Emergence and Acquisition of Fluoroquinolone-Resistant Gram-Negative Bacilli in the Intestinal Tracts of Mice Treated with Fluoroquinolone Antimicrobial Agents

2008 ◽  
Vol 52 (9) ◽  
pp. 3457-3460 ◽  
Author(s):  
Michael J. Pultz ◽  
Michelle M. Nerandzic ◽  
Usha Stiefel ◽  
Curtis J. Donskey
Keyword(s):  
Klebsiella Pneumoniae ◽  
Antimicrobial Agents ◽  
High Density ◽  
Low Density ◽  
Gram Negative

ABSTRACT After mice received orogastric administration of a fluoroquinolone-resistant Klebsiella pneumoniae strain, subcutaneous treatment with ciprofloxacin, levofloxacin, and moxifloxacin promoted persistent low-density colonization in 10% to 40% of the mice, whereas treatment with clindamycin consistently promoted high-density colonization. No emergence of fluoroquinolone-resistant gram-negative bacilli was detected in the mice during or after treatment with the fluoroquinolone antimicrobial agents.

scholarly journals Isolation and Characterization of Novel Phages Targeting Pathogenic Klebsiella pneumoniae

2021 ◽  
Vol 11 ◽  
Author(s):  
Na Li ◽  
Yigang Zeng ◽  
Rong Bao ◽  
Tongyu Zhu ◽  
Demeng Tan ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Bacterial Infections ◽  
Antimicrobial Agents ◽  
Multidrug Resistant ◽  
S1 Nuclease ◽  
Isolation And Characterization ◽  
Comprehensive Knowledge ◽  
Future Challenges ◽  
Lactamase Gene

Klebsiella pneumoniae is a dominant cause of community-acquired and nosocomial infections, specifically among immunocompromised individuals. The increasing occurrence of multidrug-resistant (MDR) isolates has significantly impacted the effectiveness of antimicrobial agents. As antibiotic resistance is becoming increasingly prevalent worldwide, the use of bacteriophages to treat pathogenic bacterial infections has recently gained attention. Elucidating the details of phage-bacteria interactions will provide insights into phage biology and the better development of phage therapy. In this study, a total of 22 K. pneumoniae isolates were assessed for their genetic and phenotypic relatedness by multi-locus sequence typing (MLST), endonuclease S1 nuclease pulsed-field gel electrophoresis (S1-PFGE), and in vitro antibiotic susceptibility testing. In addition, the beta-lactamase gene (blaKPC) was characterized to determine the spread and outbreak of K. pneumoniae carbapenemase (KPC)-producing enterobacterial pathogens. Using these ST11 carbapenem-resistant K. pneumoniae isolates, three phages (NL_ZS_1, NL_ZS_2, and NL_ZS_3) from the family of Podoviridae were isolated and characterized to evaluate the application of lytic phages against the MDR K. pneumoniae isolates. In vitro inhibition assays with three phages and K. pneumoniae strain ZS15 demonstrated the strong lytic potential of the phages, however, followed by the rapid growth of phage-resistant and phage-sensitive mutants, suggesting several anti-phage mechanisms had developed in the host populations. Together, this data adds more comprehensive knowledge to known phage biology and further emphasizes their complexity and future challenges to overcome prior to using phages for controlling this important MDR bacterium.

Inhibition of Bacterial Histamine Production by Sorbate and other Antimicrobial Agents

1984 ◽  
Vol 47 (7) ◽  
pp. 508-511 ◽  
Author(s):  
STEVE L. TAYLOR ◽  
MARCI W. SPECKHARD
Keyword(s):  
Sodium Chloride ◽  
Klebsiella Pneumoniae ◽  
Bacterial Growth ◽  
Antimicrobial Agents ◽  
Sodium Hexametaphosphate ◽  
Potassium Sorbate ◽  
Sodium Polyphosphate ◽  
Histamine Production

Potassium sorbate at a concentration of 0.5% inhibited growth and histamine production by selected strains of Proteus morganii and Klebsiella pneumoniae in a trypticase-soy broth fortified with histidine (TSBH medium). At 32°C, the inhibition was effective for up to 120 h of incubation; at 10°C, the inhibition was observed through 216 h of incubation. Sodium hexametaphosphate and sodium polyphosphate did not inhibit growth of these histamine-producing bacteria at 32°C, but did slow the rate of histamine production at the 2% level. The extent of reduction of bacterial histamine production by sodium hexametaphosphate and sodium polyphosphate was most pronounced for P. morganii. Sodium chloride at levels up to 2.0% was ineffective in preventing bacterial growth and histamine production.

KPC-2 carbapenemase and DHA-1 AmpC determinants carried on the same plasmid in Enterobacter aerogenes

2014 ◽  
Vol 63 (3) ◽  
pp. 367-370 ◽  
Author(s):  
Shougang Kuai ◽  
Haifeng Shao ◽  
Lihua Huang ◽  
Hao Pei ◽  
Zhonghua Lu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Clinical Isolate ◽  
Southern Blotting ◽  
Antimicrobial Agents ◽  
Resistance Mechanism ◽  
Enterobacter Aerogenes ◽  
Carbapenem Resistance ◽  
Jiangsu Province ◽  
Republic Of China

This study was conducted to analyse the presence of a plasmid-mediated carbapenem resistance mechanism in a clinical Enterobacter aerogenes isolate from a patient from Jiangsu province, People’s Republic of China. PCR and sequencing confirmed that the isolate harboured Klebsiella pneumoniae carbapenemase (KPC)-2, DHA-1 and TEM-1 β-lactamase genes. Both the KPC-2 and DHA-1 genes were transferred to Escherichia coli C600 by transconjugation, and Southern blotting confirmed that these two genes were located on the same plasmid, which was of approximately 56 kb in size. The Enterobacter aerogenes isolate was resistant to carbapenems and other tested antimicrobial agents. The Escherichia coli transconjugant showed reduced susceptibility but not resistance to carbapenems and other β-lactams, indicating the presence of another, possibly permeability-related, resistance mechanism in the clinical isolate.

Outbreak of Carbapenem-Resistant Klebsiella pneumoniae in Puerto Rico Associated with a Novel Carbapenemase Variant

2010 ◽  
Vol 31 (05) ◽  
pp. 476-484 ◽  
Author(s):  
Christopher J. Gregory ◽  
Eloisa Llata ◽  
Nicholas Stine ◽  
Carolyn Gould ◽  
Luis Manuel Santiago ◽  
...  
Keyword(s):  
Risk Factors ◽  
Puerto Rico ◽  
Klebsiella Pneumoniae ◽  
Antimicrobial Agents ◽  
Tertiary Care ◽  
Multivariable Analysis ◽  
Control Measures ◽  
Control Group ◽  
Surveillance Culture ◽  
Carbapenem Resistant

Background.Carbapenem-resistantKlebsiella pneumoniae(CRKP) is resistant to almost all antimicrobial agents, and CRKP infections are associated with substantial morbidity and mortality.Objective.To describe an outbreak of CRKP in Puerto Rico, determine risk factors for CRKP acquisition, and detail the successful measures taken to control the outbreak.Design.Two case-control studies.Setting.A 328-bed tertiary care teaching hospital.Patients.Twenty-six CRKP case patients identified during the outbreak period of February through September 2008, 26 randomly selected uninfected control patients, and 26 randomly selected control patients with carbapenem-susceptibleK. pneumoniae(CSKP) hospitalized during the same period.Methods.We performed active case finding, including retrospective review of the hospital's microbiology database and prospective perirectal surveillance culture sampling in high-risk units. Case patients were compared with each control group while controlling for time at risk. We sequenced theblaKPCgene with polymerase chain reaction for 7 outbreak isolates and subtyped these isolates with pulsed-field gel electrophoresis.Results.In matched, multivariable analysis, the presence of wounds (hazard ratio, 19.0 [95% confidence interval {CI}, 2.5-142.0]) was associated with CRKP compared with noK. pneumoniae.Transfer between units (adjusted odds ratio [OR], 7.5 [95% CI, 1.8-31.1]), surgery (adjusted OR, 4.0 [95% CI, 1.0-15.7]), and wounds (adjusted OR, 4.9 [95% CI, 1.1-21.8]) were independent risk factors for CRKP compared to CSKP. A novelK. pneumoniaecarbapenemase variant (KPC-8) was present in 5 isolates. Implementation of active surveillance for CRKP colonization and cohorting of CRKP patients rapidly controlled the outbreak.Conclusions.Enhanced surveillance for CRKP colonization and intensified infection control measures that include limiting the physical distribution of patients can reduce CRKP transmission during an outbreak.

scholarly journals Surveillance and Correlation of Antibiotic Prescription and Resistance of Gram-Negative Bacteria in Singaporean Hospitals

2010 ◽  
Vol 54 (3) ◽  
pp. 1173-1178 ◽  
Author(s):  
Li-Yang Hsu ◽  
Thean-Yen Tan ◽  
Vincent H. Tam ◽  
Andrea Kwa ◽  
Dale Andrew Fisher ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Correlation Analysis ◽  
Cross Correlation ◽  
Bacterial Resistance ◽  
Antimicrobial Agents ◽  
Antibiotic Prescription ◽  
Time Lag ◽  
Gram Negative ◽  
E Coli ◽  
Cross Correlation Analysis

ABSTRACT A surveillance study was performed in four Singapore public hospitals from 2006 to 2008 to determine the correlation between antibiotic prescription and Gram-negative bacterial antimicrobial resistance. Targeted organisms included ceftriaxone- and ciprofloxacin-resistant Escherichia coli and Klebsiella pneumoniae, as well as imipenem-resistant Pseudomonas aeruginosa and Acinetobacter spp. Antibiotic prescription data were collated in the WHO anatomical therapeutic chemical (ATC)/defined daily dose (DDD) format, while antibiotic resistance was expressed as incidence density adjusted for total inpatient-days every quarter. Individual trends were determined by linear regression, while possible associations between antibiotic prescription and resistance were evaluated via cross-correlation analysis. Results over 3 years indicated significantly rising incidence densities of ceftriaxone- and ciprofloxacin-resistant E. coli and imipenem-resistant Acinetobacter spp. (blood isolates only). Antimicrobial-resistant Klebsiella pneumoniae rates declined. The prescription rates of piperacillin-tazobactam, ertapenem, meropenem, ciprofloxacin, and levofloxacin increased significantly, while imipenem and moxifloxacin prescription decreased. Cross-correlation analysis demonstrated possible associations between prescription of fluoroquinolones and ciprofloxacin-resistant E. coli (R 2 = 0.46), fluoroquinolones and ceftriaxone-resistant E. coli (R 2 = 0.47), and carbapenems and imipenem-resistant Acinetobacter spp. (R 2 = 0.48), all at zero time lag. Changes in meropenem prescription were associated with a similar trend in imipenem-resistant Acinetobacter blood isolates after a 3-month time lag. No correlation was found between cephalosporin use and resistance. In conclusion, our data demonstrated correlation between prescription of and Gram-negative bacterial resistance to several, but not all, key antimicrobial agents in Singapore hospitals. In areas where Gram-negative bacterial resistance is endemic and prescription of broad-spectrum antimicrobial agents is high, factors other than antimicrobial usage may be equally important in maintaining high resistance rates.

scholarly journals Inoculum size effects in blaIMP-6 and plasmid-mediated quinolone resistance gene-positive Enterobacteriaceae in Japan

2019 ◽  
Author(s):  
Yoshihiko Ogawa ◽  
Ryuichi Nakano ◽  
Kei Kasahara ◽  
Tomoki Mizuno ◽  
Nobuyasu Hirai ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Drug Resistance ◽  
Klebsiella Pneumoniae ◽  
Size Effect ◽  
Resistance Gene ◽  
Size Effects ◽  
Antimicrobial Agents ◽  
Inoculum Size ◽  
Experimental Strains

AbstractThe aim of this study was to examine the resistance genes in clinical isolates which produced IMP-6 type metallo-β-lactamase lactamase (MBL) and had mildly reduced susceptibilities to levofloxacin and/or amikacin. The inoculum size effect was also assessed. A total of 14 Enterobacteriaceae isolates (2 Escherichia coli and 12 Klebsiella pneumoniae) which produced IMP-6 MBL, and had mild increases in their MICs for levofloxacin and amikacin were examined. Thirteen out of 14 isolates harbored CTX-M-2, with the remaining isolate co-harboring CTX-M-2 and CTX-M-1 as ESBLs. All isolates carried one or more PMQRs; aac(6′)-Ib-cr was the most prevalent (92.8%), followed by oqxA (64.3%), qnrS (42.9%), oqxAB (21.4%), and qnrB (14.3%). The inoculum size effects were significant in all strains for meropenem, 13 for imipenem, 7 for levofloxacin, and 3 for amikacin. Conjugation was successfully performed with 8 isolates and 11 strains were obtained. Eleven of the experimental strains (100%), and 8 strains (72.7%) showed inoculum size effects for meropenem and imipenem, respectively. No inoculum size effect was seen for levofloxacin. Four strains harbored qnr genes and 2 strains harbored qnr genes and QRDR mutations concurrently. blaIMP-6 positive Enterobacteriaceae with mildly reduced susceptibilities to levofloxacin and/or amikacin also harbored at least one plasmid-mediated drug resistance gene. These represent an unrecognized threat, capable of compromising the in vitro activity of many classes of antimicrobial agents. We conclude that IMP-6 MBL plays an important role in decreasing the MIC for carbapenems, whereas qnr does not for levofloxacin.

scholarly journals A Sequence Type 23 Hypervirulent Klebsiella pneumoniae Strain Presenting Carbapenem Resistance by Acquiring an IncP1 blaKPC-2 Plasmid

2021 ◽  
Vol 11 ◽  
Author(s):  
Rushuang Yan ◽  
Ye Lu ◽  
Yiwei Zhu ◽  
Peng Lan ◽  
Shengnan Jiang ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Antimicrobial Agents ◽  
Carbapenem Resistance ◽  
High Serum ◽  
Sequence Type ◽  
Infection Model ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Molecular Features ◽  
Carbapenem Resistant

Hypervirulent Klebsiella pneumoniae strains are typically associated with severe infections and susceptible to most antimicrobial agents. In 2017, a carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) strain was isolated from the sputum of a chronic obstructive pulmonary disease (COPD) patient in Zhejiang, China. The goal of the present study was to characterize the molecular features of the CR-hvKP isolate ZJ27003 and its blaKPC-2-harboring plasmid p27003_KPC. Antimicrobial susceptibility was evaluated using the broth microdilution and agar dilution methods. String tests, serum-killing and mouse survival assays were performed to assess virulence, and plasmid conjugation was performed by filter mating. The complete genome sequence of ZJ27003 was acquired using a hybrid assembly of Illumina and Nanopore platform data. The sequence type (ST) of this CR-hvKP isolate was identified as ST23, which exhibits hypervirulence with high serum resistance and murine infection model. The strain is also resistant to carbapenems (imipenem, meropenem and ertapenem), aztreonam and cephalosporins. Additionally, the CR-hvKP isolate carries a 36,708-bp blaKPC-2-harboring plasmid, named p27003_KPC, belonging to the P1 incompatibility (Inc) group. The backbone of p27003_KPC is similar to that of a blaGES-5-harboring Pseudomonas aeruginosa plasmid, in which the blaGES-5 and its surrounding regions were replaced by a blaKPC-2-containing translocatable unit derived from Enterobacteriaceae. The results of a conjugation assay revealed that p27003_KPC can be transferred from K. pneumoniae to P. aeruginosa PAO1 and make the recipient resistant against carbapenem. The identification of a carbapenem-resistant hypervirulent K. pneumoniae isolate carrying and disseminating the blaKPC-2 gene highlights a severe threat to public health.

scholarly journals Research of Associated Resistance to Antimicrobial Agents of Extended Spectrum Beta-Lactamases Escherichia Coli and Klebsiella pneumoniae Strains Isolated in Senegal

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ngom B ◽  
◽  
Wade SF ◽  
Diop TA ◽  
Diagne R ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Antimicrobial Agents ◽  
Diffusion Method ◽  
Drug Resistant ◽  
Beta Lactamases ◽  
E Coli ◽  
Sick People ◽  
Extended Spectrum ◽  
Extended Spectrum Beta Lactamases

Introduction: Some strains of Escherichia coli and Klebsiella pneumoniae produce Extended Spectrum Beta-Lactamases (ESBL) may be responsible for various infections such as urinary infections. These Sick people are treated in the very serious cases by association antibiotics to class to betalactamins, aminosids and quinolons. But proliferation of multi-drug resistant strains involves decreasing therapeutic success. That’s why epidemiological study must be done in all laboratories of bacteriology. Purpose: The aim of the study was to research the resistance phenotypes of our E. coli and K. pneumoniae ESBL strains compared to others families of antibiotics. Material and methods: Thirty two (32) Extended Spectrum betalactamases E. coli and K. pneumoniae strains isolated from either hospitalized patients or sick people who came for consultation were studied. Susceptibility to antimicrobial agents was determined using an antibiotic disk (Bio-Rad) diffusion method on Mueller-Hinton agar (Bio-Rad). The results were interpreted according to the Standards of the French Antibiogram Committee (CA-SFM). Results: The study showed that most of these strains were multi-drug resistant. They were resistant to many beta-lactamines antibiotics. E. coli strains were also resistant at 70,34% to aminosids, at 96,72% to quinolons, at 58,3% to cotrimoxazol, at 26,1% to chloramphénicol and at 21,4% to colistin ; about K. pneumoniae, they were resistant at 72,6% to aminosids, at 88,95% to quinolons, at 86,7% to cotrimoxazol, at 44,4% to chloramphénicol and at 25% to colistin. But all these strains were sensitive at 100% to l’imipenem.

Sign in / Sign up

Export Citation Format

Share Document