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Occurence of Enterobacteriaceae producing extended-spectrum beta-lactamases (ESBL and AmpC type) in patients with community acquired urinary tract infection
JÍROVÁ, Jessica
Antibiotic resistance is a global problem and is increasing every year. As urinary tract infections are one of the most common causes for prescribing antibiotics, the incidence of bacteria resistant to commonly used antimicrobials is increasing. Representatives of Enterobacteriaceae, a gramnegative bacteria, are among the most common pathogens causing UTIs. They are producers of beta-lactamases, that break down and inactivate beta-lactam antibiotics, that are commonly used therapeutics to treat UTIs. The theoretical part of the bachelor thesis deals with the characteristics of community-acquired urinary tract infections, especially their diagnosis, therapy and prevention. General properties and laboratory diagnostics of the Enterobacteriaceae family are described here. The final part outlines the content of antibiotic policy and centers in the Czech Republic. The description of the action of antimicrobial substances, specifically beta-lactam antibiotics, follows. The following is a division of the mechanisms of antibiotic resistance. Attention is focused on the description of beta-lactam resistance, the production of beta-lactamase enzymes (especially of the ESBL and AmpC types), which inactivate beta-lactam antibiotics. The theoretical part ends with a description of laboratory diagnostics of beta-lactamases (ESBL and Ampc types). The practical part deals with urine sample processing in a microbiology laboratory and the detection of enterobacteria producing extended-spectrum beta-lactamases. The process involves urine collection, transport and culture process of the sample on the appropriate diagnostic medium. This is followed by microscopy of the microbes and isolation of a pure colony of microbes from the family Enterobacteriaceae. Enterobacteria is diagnosed by using biochemical properties of a microbe grown on a special Švejcar medium and by changing colors by reagents in the INDOL test. A set of tests is used to demonstrate the production of beta-lactamases, ESBL and AmpC types. Disk diffusion test shows whether the strain is sensitive or resistant to the relevant antimicrobial agent. The DDST test is used to detect Enterobacteria producing ESBL and AmpC beta-lactamases. Chromogenic ESBL medium identifies strains producing extended-spectrum beta-lactamase. The research was performed in the Stafila microbiological laboratory for a period of 3 months. The frequency of individual representatives of enterobacteria causing community-acquired urinary tract infections was compared here, depending on the age and type of urine collected. Another comparison was in terms of the percentage of ESBL and AmpC positivity in polyresistant Enterobacteriaceae, also depending on the age and type of urine collected. Escherichia coli is the most common pathogen diagnosed in the urine of patients with urinary tract infections, with up to 60.67%. Proteus mirabilis and Klebsiella pneumoniae should not be overlooked either. The average age of patients with urinary tract inflammation is 54 years. ESBL positive samples were 9% of the total number of processed urine. AmpC positive urine was slightly less, 4% of the total urine count. According to the results, the most vulnerable group of patients are the elderly in care facilities, with an permanent catheter or one-time catheterisation. The final part of the bachelor thesis points to possible solutions to the problem of poly-resistant bacteria in patients with community-acquired urinary tract infections.
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Colistin resistance in clinically important Enterobacteriaceae
Smělíková, Eva ; Tkadlec, Jan (advisor) ; Ježek, Petr (referee)
Colistin is a last-resort antibiotic used to treat serious infections caused by Enterobacteriaceae and other multidrug resistant gram-negative bacteria. Recently discovered plasmid-borne colistin resistance, mediated by the mcr genes, poses a serious risk to colistin therapy. The aim of this diploma thesis was to map the occurrence of Enterobacteriaceae carrying the mcr-1 to 8 genes in hospitalized patients, travellers, prospective colistin-resistant clinical isolates and in a retrospective collection of Enterobacteriaceae using a combination of selective cultivation and qPCR. Isolates with a detected mcr gene were characterized by Whole-Genome Sequencing. The localization of mcr genes was determined and other resistance genes and plasmids were identified. Furthermore, the physiological profile of selected colistin- resistant Escherichia coli isolates was characterized. In the presence of a subinhibitory amount of colistin, a strain carrying the mcr-1 gene may be favored. Later, the mcr-9 gene was described and its occurence was subsequently tested retrospectively. Enterobacter spp. isolates carrying the mcr-9 gene were mostly colistin-sensitive but, in some cases, resistance was induced after exposure to sublethal doses of colistin. The results of the study show that the incidence of plasmid-mediated...
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Resistance of Escherichia coli to selected antibiotics in the Písek district in 2016
BROMOVÁ, Karolína
The aim of my work was to gather information on resistance of Escherichia coli to selected antibiotics. To show wrong use of antibiotics and to prove that this problem should begin to solve. The research part was performed by data processing, cultivation, sensitivity determination and determination of a phylum using various laboratory methods. In my research, I used Escherichia coli from the urine I used phyla previously designated. To determine the correct phylum of Enterobacteriaceae, I made use of biochemical tests such as the ENTERO test 24 N and ESBL MAST test, for the Escherichia coli phyla, I have used the INDOL test and VPT test. To determinate sensitivity to antibiotics, I used the M.I.C disk diffusion test.
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Resistances of Escherichia coli to selected antibiotics in a district of Písek for the year 2016
BROMOVÁ, Karolína
Resistance to antibiotics is becoming a global problem. In my work I focused on the resistance of Escherichia coli in the Písek district in 2016. Escherichia coli is the most common cause of urinary tract infections. On average, every second woman and every fifth male will experience urinary tract infection. Resistance problems have met for many years. Previously effective antibiotics are now ineffective. Often they have to go beyond wide-spectrum antibiotics that have a number of side effects (diarrhea, yeast infections), are more expensive and have an impact on the economy. In the Czech Republic, we do not yet have the same level of resistance as in other countries, In Greece. Therefore, we should take an example from other countries and avoid massive use of antibiotics. The objectives of my work were to collect information on Escherichia coli resistance, to compare the differences between adult and pediatric patients and to determine the degree of ESBL strains in the Písek district in 2016. I compare the results of my research with the results of the urinalysis study of NRL SZÚ in Prague for 2016. In the theoretical part, I have dealt mainly with antibiotic characteristics, antibiotic resistance methods and briefly describe Escherichia coli. In its practical part, methods of identifying bacteria (ENTERO test 24N) are described. Principles of biochemical tests (VP test, INDOL test) to help us determine what type of bacteria might be. I also describe the principles and use of sensitivity assays (Disk diffusion test, M.I.C. microdilution test). Using the ESLB MAST test, I discovered the extent to which ESBL beta-lactamase-producing strains with extended spectrum of effect, which cause multi-resistance, were found in the Písek district. Furthermore, the practical part contains evaluation of resistance statistics on selected antibiotics, which I processed from data from the clinical microbiology of Písek Hospital. For my observation of Escherichia coli resistance, I chose 5 types of antibiotics used in the treatment of urinary tract infections - Amoxicillin, amoxicillin + clavulanate, nitrofurantoin, cefotaxim, and gentamicin. The results of my work demonstrate that resistance to selected antibiotics is relatively high. It appears that women have more resistant strains than men, which can be explained by the fact that women are more likely to have urinary infections and more ESBL strains are present. No ESBL strains are present in pediatric patients (0 - 19 years). It also follows that girls are more likely to suffer from urinary infections than boys, with the only exception being girls and boys aged 0-3 years old, according to my research with urinary infections suffer more boys than girls.
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Detection of extended-spectrum beta-lactamase (ESBL) producers in community and in a hospital
POLENOVÁ, Lucie
The incidence of bacteria resistant to available antibiotics has become an important problem. Statistics show the rising number of resistant bacteria worldwide. Bacteria have ability to be resistant naturally or they develop from point mutation of genes and relay it between species or kinds. The study was made because of significance and relevance of this problem. In theoretical part the study is focused on the functional parts of bacterial cell, which participate in mechanisms of resistance. Beta - lactam antibiotics are described in more detail. The research took place in Hospital České Budějovice, a. s. during 2013. The study aimed to determine the frequency of ESBL positive producers in this hospital and to compare with frequency in community, and to identify units with highest frequency of ESBL producers. Pathogens are isolated from clinical material, being delivered to bacteriology lab in Hospital České Budějovice, a. s. Resistant samples were examined with double disc synergy test (DDST) and quantitative method based on principle of minimal inhibition concentration in combination with chromogenic agar. The prevalence rate of ESBL producers is average to low in Hospital České Budějovice, a. s. During 2013, 12, 347 isolates were identified, ESBL production was identified in 226 isolates. Escherichia coli (183 isolates), Klebsiella pneumoniae (16 isolates), and Enterobacter cloacae (15 isolates) were the most prevalent species. The number of ESBL producers was lower compared to 2012, 2011, and 2010.
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Etiological agents of enteric infections in children, their detection and identification in microbiological laboratory
PETROVÁ, Jana
The thesis deals with intestinal infections in children including cultivation and diagnostics of pathogens. The attention was focused on children population in the age up to 15 years. The practical part was carried out and the data was gained in the laboratory of Laboma, microbiology laboratory Ltd. The biological material was the smear from the rectum of an infected child. In the theoretical part the attention was paid to the most frequent intestinal agens. From the bacterial agens these are the representatives from the tribe Enterobacteriaceae. Beside intestinal these patogens cause also some other diseases. That is why the thesis is focused on the species Salmonella enterica, Shigella sp., Escherichia coli a Yersinia enterocolitica. Rotaviruses and adenoviruses belong among the mentioned viral pathogens. The objective of the thesis was the evaluation of the operating sequence from the reason of the fastest and the most accurate findings of etiological agens of a particular sick condition- in this case it is a diarrhoeal disease. Further it is the statistical data evaluation from the point of occurrence of intestinal pathogens (bacteria and viruses) in children in the year of 2008. During the identification of all agens I used the available diagnostic methods carried out in routine microbiology practice. In bacterial invadors they were: cultivation, isolation, serotypization, and final bio chemical identification (bio chemical row). In viral invadors they were: the determination of antigen in the stool on the basis of commercially produced tests. In biological material I proved the most of mentioned bacteria and viruses. I found out that for the replacement detection of bacteria Salmonella enterica serotype Enteritidis it is not possible to rely only on isolation and serotypization. The determination of fenotypical characteristics using bio chemical row is authoritative and designating. I evaluated the occurrence of the most agens in target population statistically. From the graph it is evident that in bacteria Salmonella enterica serotype Enteritidis dramatically prevails. The result of the study is the fact that if the microorgaism is to be correctly identified it is necessary to proceed according to the most suitable available diagnostic methods, by which means the risk of agens replacement is eliminated.
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