Original title: Ampicilin rezistentní beta-laktamáza negativní kmeny Haemophilus influenzae izolované v ČR v letech 2010-2018
Translated title: Ampicillin-Resistant β-lactamase-negative Haemophilus Influenzae Strains Isolated in the Czech Republic in 2010-2018
Authors: Jakubů, Vladislav
Document type: Rigorous theses
Year: 2022
Language: cze
Abstract: [cze] [eng]
Podle výsledk pravidelné surveillance rezistence bakteriálních p vodc infekcí dýchacích cest vzr stá v eské republice po et kmen Haemophilus influenzae s neenzymatickou rezistencí k -laktamovým antibiotik m. Neenzymatická rezistence je podmín na mutacemi v genu ftsI kódujícím penicilin-vážící proteiny (PBP3), jejichž d sledkem je snížená schopnost vázat -laktamová antibiotika. Pr kaz tohoto typu rezistence je obtížn jší než detekce -laktamázy, která je u H. influenzae stále nej ast jší p í inou rezistence k aminopenicilin m. Analýzou souboru 228 kmen H. influenzae bylo zjišt no, že nejvyšší možný záchyt (99,5 %) izolát s neenzymatickou rezistencí zp sobenou mutacemi v genu ftsI, je možno v rutinní praxi dosáhnout p i sou asném vyšet ení citlivosti v i penicilinu, ampicilinu, amoxicilinu a cefuroximu diskovou difúzní metodou dle metodologie EUCAST. V sou asnosti doporu ovanou metodou EUCAST s využitím pouze penicilinu byl záchyt mutací nižší, 95,7 %. Sekvena ní analýza prokázala zna nou variabilitu mutací genu ftsI. V souboru 228 kmen bylo zjišt no celkem 37 r zných kombinací aminokyselinových zám n, které se vyskytly na 23 pozicích v proteinu PBP3 (V329I, D350N, S357N, A368T, M377I, S385T, A388V, L389F, P393L, A437S, I449V, G490E, I491V, R501L, A502S, A502T, A502V, V511A, R517H, I519L, N526K, A530S a... According to the results of regular surveillance of resistance of bacterial pathogens of respiratory tract infections, the number of Haemophilus influenzae strains with non-enzymatic resistance to -lactam antibiotics is increasing in the Czech Republic. Non-enzymatic resistance is caused by mutations in the ftsI gene encoding penicillin-binding protein (PBP3), which result in a reduced ability to bind -lactam antibiotics. Demonstration of this type of resistance is more difficult than detection of -lactamase, which is still the most common cause of aminopenicillin resistance in H. influenzae. Analysis of a set of 228 H. influenzae strains revealed that the highest possible detection (99.5%) of isolates with non-enzymatic resistance due to mutations in the ftsI gene could be achieved in routine practice by simultaneous examination of penicillin, ampicillin, amoxicillin and cefuroxime disc diffusion method according to the EUCAST methodology. The currently recommended EUCAST method using only penicillin had a lower mutation detection rate of 95.7%. Sequence analysis showed considerable variability in ftsI gene mutations. In the set of 228 strains, a total of 37 different combinations of amino acid substitutions were found to occur at 23 positions in the PBP3 protein (V329I, D350N, S357N, A368T, M377I, S385T,...

Institution: Charles University Faculties (theses) (web)
Document availability information: Available in the Charles University Digital Repository.
Original record: http://hdl.handle.net/20.500.11956/177810

Permalink: http://www.nusl.cz/ntk/nusl-510828


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