klebsiella pneumoniae

The ability of Klebsiella pneumoniae as an opportunistic bacterium in hospital infections, by producing biofilm on food utensils and hospital surfaces, has adverse effects on the treatment and survival of hospitalized patients. The present study was conducted with the aim of investigating the effect of TiO2 nanoparticles on Klebsiella pneumoniae biofilm formation.

TiO2 nanoparticles were produced using sol-gel method. 62 strains of Klebsiella pneumoniae were isolated from three hospitals in Tehran. Antimicrobial activity of TiO2 nanoparticles against biofilm-producing and antibiotic-resistant strains was determined by disk diffusion method. Definitive identification of the isolates was done through common biochemical tests and 16S rRNA sequencing, and the expression of treC, mrkD, sugE, luxS and 16SrRNA genes was investigated by real time PCR.

The data showed that the ability to form biofilm among isolates obtained from sputum was higher than other isolates. TiO2 nanoparticles with a concentration of 256 μg/ml inhibited biofilm production in fourteen isolated strains. Comparison of LuxS gene expression in Klebsiella pneumoniae untreated and treated with TiO2 showed that the level of gene expression decreased by 3.85 times (p = 0.002).

This study showed that the synthesized TiO2 nanoparticles are effective against the formation of biofilm in Klebsiella pneumoniae strains resistant to several drugs and can be reliable and useful as inorganic antimicrobial agents.

Klebsiella pneumoniae is a gram-negative bacillus of the Enterobacteriaceae family. Despite being part of the natural human microflora, this is an opportunistic pathogen and a major cause of nosocomial infections. The increased emergence of multidrug resistance in Klebsiella pneumoniae has limited the treatment options for this bacterium. Carbon nanotubes (CNT), by improving the stability and solubulity of drugs, could increase the effectiveness of drugs for treatment. The aim of this study is to investigate the antibacterial effect of nanofluid containing functionalized multi-walled carbon nanotubes (f-CNT-NF) on Klebsiella pneumoniae isolated from clinical specimens. For the strain confirmation, biochemical ,API20E kit, and additional differential tests were performed, and antibiotic susceptibility test was performed by the disk diffusion method. The studied strain showed a resistance to all antibiotics such as cefepime.The minimum inhibitory concentration (MIC) was determined using the antibiotic micro dilution method. The MIC was determined in five effect modes including antibiotic (Ab), nanofluid containing functionalized multi-walled carbon nanotubes (f-CNT-NF) , nanofluid containing multi-walled carbon nanotubes (CNT-NF) ,Ab in combination with f-CNT-NF and Ab with CNT-NF. Nevertheless the individual effects of 10 µg mL-1 cefepime or 80 µg of nanofluid with f-CNT-NF did not inhibit the growth of the bacteria, but the co-administration of 10 µg mL-1 cefepime with 80 µg of the f-CNT-NF could inhibit the bacteria`s growth. It was concluded that f-CNT-NF could be more effective in drug delivery at lower concentrations than the free state, which could be used as a tool for optimal drug delivery.

 

Klebsiella pneumoniae (K. pneumoniae) is one of the important human pathogens among which emergence of antibiotic resistant results in many problems in therapeutic process. Class 1 integron genes may facilitate the conferring of antibiotic resistance among bacterial population. In the present study, isolation of K. pneumoniae from urine samples, determining the antibiotic resistant pattern, and evaluating the presence of class 1 integron genes were investigated.

The obtained isolated bacteria were confirmed via biochemical tests. Evaluating the bacterial resistance against 10 different antibiotics was performed by agar disk diffusion method and antibiotic resistant pattern was also determined. PCR method was used in order to detect the presence of class 1 integron genes among isolates.

80 K. pneumoniae were isolated from the urine sample of attendees of clinical laboratories in Karaj. Meropenem and Nitrofurantoin were the most and least effective antibiotics, respectively. 16 isolates were considered as multi drug resistance (MDR) among which resistance to all 10 tested antibiotics was also observed. 29 isolates were also positive in terms of class 1 integron genes.

Treatment with the following antibiotics; Meropenem, Levofloxacin, Imipenem, and Gemtamicin, may be successful, since more than 80% of the isolates were susceptible to them. However, presence of MDR as well as detecting class 1 integron genes may be an alarming for infections caused by K. pneumoniae.

Knowing about the increase in the antibiotic resistance among K. pneumoniae isolates, the presence of MDR isolates, and also detecting the presence of genes involved in dissemination of resistant isolates may help to choose the more effective therapies.

Klebsiella pneumoniae is a human opportunistic pathogen. Biofilm formation is one of the important properties of this bacteria that leads to the development of multidrug-resistant phenotypes. In recent years, Nanoparticle Technology (NP) has been an important field in a wide range of studies. In this study, the effects of chemical nanoparticles on biofilm formation and antibiotic resistance of Klebsiella pneumoniae were investigated.

Overall, 340 samples from patients were collected from different hospitals in Tehran. Colonies were tested to identify bacteria based on standard techniques. In each bacterium, the presence of important biofilm formation genes in Klebsiella pneumoniae was detected by Multiplex PCR and their expression levels were analyzed using the Real-time PCR method. The effect of chemical nanoparticles of iron oxide on biofilm formation and antibiotic resistance was also investigated.

Sixty isolates of Klebsiella pneumoniae were identified based on standard techniques. The results showed that both types of iron oxide nanoparticles had a significant effect on inhibiting the formation of biofilm and antibiotic resistance of this bacterium (p <0.001). In addition, the combination of iron oxide nanoparticles and ciprofloxacin had significant antimicrobial effects compared to other compounds (p <0.001).

The formation of biofilm and the antibiotic resistance of Klebsiella pneumoniae isolates were effectively inhibited in response to iron oxide nanoparticles. The results could be useful in controlling multiple drug-resistant infections in hospitalized patients.

The prevalence of infection, along with the spread of antibiotic-resistant bacteria has caused the antibacterial peptide, bacteriocins, to be considered. The purpose of this study was to compare the antibacterial effect of bacteriocin-producing bacteria. The inhibitory activity of bacteria isolated from different regions of Semnan soil, Dasht Desert (Semnan University Bacterial Culture Collection; DDBCC) was studied against the indicators by agar diffusion method. Candidate strains were identified by biochemical and molecular tests. Concentrating the selected bacteriocins by ammonium sulfate saturation, the effects of biofilm destruction were studied. Then, using a thin layer chromatography the selected bacteriocins were purified and their antimicrobial activity was confirmed. The 16s rRNA sequencing results showed 98% similarity of DDBCC38 and DDBCC51 isolates to E. coli and 96% similarity of the DDBCC46 isolate to Bacillus subtilis. Concentrated DDBCC51 and DDBCC38 bacteriocins inhibited the growth of Bacillus cereus, Bacillus anthracis, and Klebsiella pneumonia after 52 hours. Pseudomonas aeruginosa and Staphylococcus aureus biofilms were destructed by DDBCC51 and DDBCC38 bacteriocins 12.0% and 40.0%, and 19.6% and 40%, respectively. In contrast, concentrated DDBCC46 bacteriocin was effective on K. pneumonia and P. aeruginosa in 72 hours but had no effect on biofilm destruction. The purification of DDBCC38 and DDBCC51 bacteriocins by thin layer chromatography resulted in 2 mm increasing of inhibition zone diameter against K. pneumoniae. However, purified DDBCC46 bacteriocin reduced it by 4 mm. Considering the anti-biofilm and antagonistic properties of the respective isolates, further studies for optimization of the production conditions and molecular identification of the produced
bacteriocin are proposed

Aim and Extended-spectrum beta-lactamase of CTX-M type is considered as an Important mechanism resistant to beta-lactamases in gram- negative pathogen and is widely increasing. Klebsiella pneumoniae species are able to produce extended-spectrum beta- lactamase (ESBLs). The aim of this study was to detect the prevalence of CTX-M gene in ESBLs produsing Klebsiella pneumoniae isolated form patients in different region of TEHRAN city from December2016 to july 2017 by using PCR method.
Material and In this analytical- descriptive study antibacterial susceptibility patterns of 176 Klebsiella pneumoniae tested to Cefepime, Ampicillin, Gentamicin, Amikacin, Cefalotine, Ceftazidime, Piperacillin, Ciprofloxacin, Imipenem, Cefotaxime , Nitrofurantoin, Trimethoprim using disk diffusion method. In addition, confirmatory test for detecting ESBLs phenotypes was performed using Cefotaxim-Clavulanic acid combination disk. The presence of CTX-M gene was assessed by using PCR.
Confirmatory phenotypic test showed 56.81% of the isolates were ESBL positive. The prevalence of CTX-M gene in isolated Klebsiella pneumoniae was 28%. In this study, the highest resistance was observed for ampicillin antibiotics (24.88%) and the least resistance to antibiotic imipenem (6.06).
High frequency of CTX-M gene in ESBL produsing isolates indicates that this enzyms plays an important role in resistance to beta lactam containing anti biotics. Therefore, proper infection control tools and appropriate therapeutic approaches in different parts of the hospitals are necessary to prevent their release.

Aim and Extended spectrum β-lactamases (ESBLs) have emerged as a major threat worldwide with limited treatment options. This study aimed to determine the antibiotic susceptibility pattern and the evaluation of TEM genes producing in Escherichia coli and Klebsiella pneumonia isolates collected from clinical samples. Bacteria were isolated and identified from the different samples in patients sent to laboratory of shahid Beheshti University in Tehran in 2011. Isolates were then tested for antimicrobial susceptibility by disc diffusion and examined for TEM genes production by polymerase chain reaction using specific primer. Out of 100 studied nosocomial infection specimens, 50 isolates were klebsiella pneumonia of which 34 percent were ESBL producer and all were positive for TEM gene, resistance of Cefotaxime was 90 percent which is the highest degrees of resistance and lowest degrees of resistance to Imipenem was 4 percent. Among the 50 isolates of Escherichia coli of which 14 percent were ESBL producer and all were positive for TEM gene, resistance of Cefexime was 90 percent which is the highest degrees of resistance and lowest degrees of resistance to Meropenem was 6 percent. Due to relatively high prevalence of ESBL-producing bacteria in the studied population, antibiogram test are advised for appropriate treatment.

Klebsiella pneumoniae is an opportunistic pathogen that causes a significant proportion of community and hospital acquired infections. Among the antibiotic classes، β -lactams are often used for treatment of these infections. However، bacterial resistance has developed mostly due to the production of a variety of β-lactamases، especially the extended-spectrum β-lactamases (ESBL). In this research، one hundred and ninety six K. pneumoniae isolates were collected from Imam Hussein Hospital in Tehran during 2008-2012. Antibiotic susceptibility was determined by disc diffusion and extended-spectrum β-lactamase production was shown by the phenotypic confirmatory test. Carriage of blaSHV، blaTEM and blaCTX-M genes was detected by PCR and specific primers. ESBL production was examined in relation to the presence of blaSHV، blaTEM and blaCTX-M genes. Overall، 160 isolates (81. 6 %) carried blaCTX-M، 104 (53. 06 %) had blaTEM and 82 (41. 8%) harbored the blaSHV genes. ESBL production was observed in 92 isolates (46. 9%) of which، 77 (83. 6 %) harbored blaCTX-M، 57 (61. 9 %) had blaTEM and 43 (46. 7%) carried blaSHV. Finally، 7 (7. 6 %) did not harbour any of the 3 genes and 24 (26. 08%) carried all three. Our results show that gene carriage does not necessarily account for its expression and ESBL phenotype. In addition، the presence of blaCTX -M was dominant in our urinary Klebsiella pneumoniae isolates followed by blaTEM and blaSHV.

Carbapenem is the last defensive line against gram negative bacterial infections that are resistant to extended spectrum antibiotics. Hence، using a proper method for determining the production of carbapenemase enzyme which controls the infection factors resistant to carbapenem antibiotic seemed to be essential. The aim of this study was qualitative analysis of Hodge test for finding a suitable method in determining carbapenemase. Thirty six samples of Klebsiella pneumoniae with multiple antibiotic resistances capable of producing carbapenemase enzyme were collected from medical centers and laboratories، and approved through CHROMagar method. All the samples were analyzed with regards to the form of sensitive zone as clover shape in Hodge test، according to CLSI instruction. All collected samples were identified for carbapenemase producing with CHROMagar KPC method. Thirty samples were reported positive with Hodge test، respectively. The sensitivity of Hodge test was calculated to be 83. 3%. Also، all the negative control isolations were accompanied by negative result and its sensitivity was reported to be 100%. On the other hand، it was observed that all the positive cases were resistant to antibiotics including Ampicillin، Amikacin، Gentamicin، Tetracycline، Ceftazidime، Ciprofloxacin and Imipenem. Discussion and According to the obtained results from Hodge test on the collected samples، using this method was determined to be appropriate in primary diagnosis and under the conditions where preparation of specific culture media or using molecular methods was not possible.