BACKGROUND: In 2023, a significant increase in Streptococcus pyogenes, Group A Streptococcus (GAS) culture positivity was observed in Czech microbiological laboratories. We conducted a multicentre study to obtain epidemiological data and characterise circulating strains. METHODS: Eleven microbiology departments provided data on single-patient GAS-positive cultures from 2017 to 2023. Additionally, 10 consecutive, single-patient GAS isolates from 12 hospitals were submitted in May 2023 for whole-genome sequencing and antimicrobial susceptibility testing. RESULTS: In 2023, there was a significant increase in GAS-positive cultures compared to the periods of 2017-2019 (p = 0.002), 2020-2021 (p < 0.00001), and 2022 (p = 0.001), with a disproportionate increase in children. Among 120 isolates, 12 different emm types and 16 multi-locus sequence types (STs) were identified, with emm1 (ST28, 35.0 %) and emm12 (STs 36, 101, 242, 1366, 32.5 %) being the most prevalent. Clonal clustering of emm1 and emm12 isolates across different study sites and geographic regions was demonstrated by whole-genome MLST analysis. When searching for shared virulence genes exclusive to emm1 and emm12 but absent in other emm types, immune evasion and colonisation factors (the streptococcal inhibitor of complement-sic gene in emm1, the distantly related sic-drs gene in emm12, and the sda1 gene in both) were identified. CONCLUSIONS: An upsurge in GAS infections, predominantly caused by emm1 and emm12, was identified in the Czech Republic. The combination of shared virulence factors, altered herd immunity and naïve immunity in children, resulting from contact precautions measures during the COVID-19 pandemic, may have contributed to their increased spread.

• Klíčová slova
• Streptococcal inhibitor of complement, Streptodornase, Surveillance, drs12.02 gene, sic gene,
• MeSH
• antibakteriální látky farmakologie   MeSH
• antigeny bakteriální * genetika   MeSH
• COVID-19 epidemiologie   MeSH
• dítě MeSH
• dospělí MeSH
• faktory virulence * genetika   MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• multilokusová sekvenční typizace MeSH
• předškolní dítě MeSH
• proteiny vnější bakteriální membrány * genetika   MeSH
• SARS-CoV-2 MeSH
• sekvenování celého genomu MeSH
• Streptococcus pyogenes * genetika   patogenita   izolace a purifikace   účinky léků   MeSH
• streptokokové infekce * epidemiologie   mikrobiologie   MeSH
• transportní proteiny * genetika   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• antibakteriální látky MeSH
• antigeny bakteriální * MeSH
• faktory virulence * MeSH
• proteiny vnější bakteriální membrány * MeSH
• streptococcal M protein MeSH Prohlížeč
• transportní proteiny * MeSH

While the inhalation of Thymus vulgaris L. essential oil (EO) is commonly approved for the treatment of mild respiratory infections, there is still a lack of data regarding the antimicrobial activity and chemical composition of its vapours. The antibacterial activity of the three T. vulgaris EOs against respiratory pathogens, including Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pyogenes, was assessed in both liquid and vapour phases using the broth microdilution volatilisation (BMV) method. With the aim of optimising a protocol for the characterisation of EO vapours, their chemical profiles were determined using two headspace sampling techniques coupled with GC/MS: solid-phase microextraction (HS-SPME) and syringe headspace sampling technique (HS-GTS). All EO sample vapours exhibited antibacterial activity with minimum inhibitory concentrations (MIC) ranging from 512 to 1024 μg/mL. According to the sampling technique used, results showed a different distribution of volatile compounds. Notably, thymol was found in lower amounts in the headspace-peak percentage areas below 5.27% (HS-SPME) and 0.60% (HS-GTS)-than in EOs (max. 48.65%), suggesting that its antimicrobial effect is higher in vapour. Furthermore, both headspace sampling techniques were proved to be complementary for the analysis of EO vapours, whereas HS-SPME yielded more accurate qualitative results and HS-GTS proved a better technique for quantitative analysis.

• Klíčová slova
• antimicrobial activity, broth microdilution, headspace analysis, respiratory infections, thyme, vapour phase,
• MeSH
• antibakteriální látky chemie   izolace a purifikace   farmakologie   MeSH
• Haemophilus influenzae účinky léků   MeSH
• mikrobiální testy citlivosti MeSH
• mikroextrakce na pevné fázi * MeSH
• oleje prchavé chemie   izolace a purifikace   farmakologie   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• Staphylococcus aureus účinky léků   MeSH
• Streptococcus pyogenes účinky léků   MeSH
• Thymus (rostlina) chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• oleje prchavé MeSH

In this study, a new broth macrodilution volatilization method for the simple and rapid determination of the antibacterial effect of volatile agents simultaneously in the liquid and vapor phase was designed with the aim to assess their therapeutic potential for the development of new inhalation preparations. The antibacterial activity of plant volatiles (β-thujaplicin, thymohydroquinone, thymoquinone) was evaluated against bacteria associated with respiratory infections (Haemophilus influenzae, Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes) and their cytotoxicity was determined using a modified thiazolyl blue tetrazolium bromide assay against normal lung fibroblasts. Thymohydroquinone and thymoquinone possessed the highest antibacterial activity against H. influenzae, with minimum inhibitory concentrations of 4 and 8 µg/mL in the liquid and vapor phases, respectively. Although all compounds exhibited cytotoxic effects on lung cells, therapeutic indices (TIs) suggested their potential use in the treatment of respiratory infections, which was especially evident for thymohydroquinone (TI > 34.13). The results demonstrate the applicability of the broth macrodilution volatilization assay, which combines the principles of broth microdilution volatilization and standard broth macrodilution methods. This assay enables rapid, simple, cost- and labor-effective screening of volatile compounds and overcomes the limitations of assays currently used for screening of antimicrobial activity in the vapor phase.

• Klíčová slova
• antimicrobial, cytotoxicity, macrodilution method, respiratory infections, thymohydroquinone, thymoquinone, vapor phase, volatile compound, β-thujaplicin,
• MeSH
• antibakteriální látky analýza   chemie   farmakologie   MeSH
• aplikace inhalační MeSH
• Bacteria účinky léků   MeSH
• benzochinony aplikace a dávkování   farmakologie   MeSH
• Haemophilus influenzae účinky léků   MeSH
• mikrobiální testy citlivosti MeSH
• monoterpeny aplikace a dávkování   farmakologie   MeSH
• oleje prchavé chemie   farmakologie   MeSH
• Staphylococcus aureus účinky léků   MeSH
• Streptococcus pneumoniae účinky léků   MeSH
• Streptococcus pyogenes účinky léků   MeSH
• těkavé organické sloučeniny chemie   farmakologie   MeSH
• thymol aplikace a dávkování   analogy a deriváty   farmakologie   MeSH
• tropolon aplikace a dávkování   analogy a deriváty   farmakologie   MeSH
• volatilizace MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• benzochinony MeSH
• beta-thujaplicin MeSH Prohlížeč
• monoterpeny MeSH
• oleje prchavé MeSH
• těkavé organické sloučeniny MeSH
• thymohydroquinone MeSH Prohlížeč
• thymol MeSH
• thymoquinone MeSH Prohlížeč
• tropolon MeSH

AIM OF THE STUDY: Analysis of data on the occurrence of severe infections caused by group A streptococci, emm typing of the isolated strains, and survey of resistance to the selected antibiotics. MATERIAL AND METHODS: In 2012 and 2013, 43 S. pyogenes strains were isolated from severe infections. The isolates were most often recovered from wounds and abscesses (36 patients), followed by blood culture (5 patients), sputum (1 patient), and autopsy samples (1 patient). Antimicrobial susceptibility to selected antibiotics ( penicillin, erythromycin, clindamycin, spiramycin, and tetracycline) was tested by the disk-diffusion method and the minimal inhibitory concentrations (MICs) were determined. RESULTS: In 2012 and 2013, an increase in severe streptococcal infections was observed, with 27 and 16 cases reported, respectively. Resistance to macrolides was detected in 18.5% and 12.5% of isolates, respectively, and resistance to tetracycline in 25.9% and 20% of isolates, respectively. The isolated S. pyogenes strains were most often assigned to emm type 1. Risk factors for streptococcal infection were analyzed, with injury being most often identified as a risk factor- in seven and two patients, respectively. The patients were most frequently treated by beta-lactam antibiotics (penicillin and ampicillin). In 2012, two cases were fatal. CONCLUSION: This study reports cases of invasive group A streptococcal (GAS) infection as seen in clinical practice. An increased occurrence of S. pyogenes was observed in the hospital, with the isolates exhibiting elevated resistance to erythromycin and tetracycline. It is necessary to monitor the trends of antimicrobial resistance and the distribution of emm types among group A streptococcal isolates. Cooperation of the laboratory and clinical professionals in the prevention and therapy of streptococcal infections, invasive in particular, is crucial for risk reduction.

• MeSH
• ampicilin farmakologie   MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální léková rezistence MeSH
• dospělí MeSH
• erythromycin farmakologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• makrolidy farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• mladý dospělý MeSH
• peniciliny farmakologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Streptococcus pyogenes účinky léků   genetika   izolace a purifikace   MeSH
• streptokokové infekce mikrobiologie   MeSH
• tetracyklin farmakologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ampicilin MeSH
• antibakteriální látky MeSH
• erythromycin MeSH
• makrolidy MeSH
• peniciliny MeSH
• tetracyklin MeSH

STUDY OBJECTIVES: To analyze trends in the resistance of Streptococcus pneumoniae to penicillin and macrolides and of S. pyogenes to macrolides over a 14-year period and to determine serotypes and molecular characteristics in a selected group of S. pneumoniae strains resistant to these antibiotics. MATERIAL AND METHODS: Susceptibility to antibiotics was tested by the participating laboratories by the disk diffusion method in isolates of both bacterial species from the lower and upper respiratory tract from 1996-2009. The National Reference Laboratory for Antibiotics (NRL/ATB) determined the minimal inhibitory concentrations of penicillin and erythromycin for invasive pneumococcal isolates from 2000-2009 and performed multilocus sequence analysis of selected resistant strains. RESULTS: Over the 14-year period monitored, penicillin resistance of S. pneumoniae isolates from the upper and lower respiratory tract showed a slightly downward trend similarly to blood isolates monitored since 2000. Resistance to macrolides in S. pneumoniae isolates was lower than penicillin resistance, regardless of the sample origin until 2005, but became higher than penicillin resistance in 2006 to follow a continuously upward trend since then. In 2009, the penicillin resistance rates of S. pneumoniae isolates from the upper respiratory tract, lower respiratory tract and blood were 3.5%, 5.1% and 4.7%, respectively, while the respective erythromycin resistance rates reached 8.4%, 12.2% and 5.5%. When using the new clinical breakpoints for pneumococci from pneumonia cases depending on penicillin dose and administration interval, only two (0.1%) of 1528 strains from the blood were confirmed as penicillin resistant (MIC 4 mg/l). Resistance of S. pyogenes to macrolides, reported in 16.5% of strains in 2001, sharply decreased to 9% in 2003 as a result of an intervention to promote the use of penicillin for the treatment of tonsillopharyngitis, and reached 11.1% in 2009. Among penicillin resistant strains of S. pneumoniae, the spread of clone Spain9V-3 (ST156) was confirmed, and among S. pneumoniae strains resistant to erythromycin alone, the spread of clones Poland6B-20 (ST315) and England9V-14 (ST9) was found. CONCLUSIONS: The favourable low prevalence of penicillin resistance among S. pneumoniae strains, which in addition is negligible in the light of the new clinical breakpoints for penicillin resistance in strains from patients with pneumonia, contrasts with the ever increasing resistance of this species to macrolides. The highest rates of resistance to macrolides found in the strains isolated mainly from the sputum of adult patients confirm the preference for macrolides over the drugs of choice amoxicillin or penicillin G in the treatment of adults with pneumococcal pneumonia. Further spread of successful multiresistant clones of S. pneumoniae, the presence of which has been revealed in the Czech Republic, can only be prevented by a radical reduction in overuse or misuse of antibiotics.

• MeSH
• bakteriální léková rezistence MeSH
• lidé MeSH
• makrolidy farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• peniciliny farmakologie   MeSH
• rezistence na penicilin MeSH
• Streptococcus pneumoniae účinky léků   izolace a purifikace   MeSH
• Streptococcus pyogenes účinky léků   izolace a purifikace   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• makrolidy MeSH
• peniciliny MeSH

An unusual emm53, T-28/T-non-typeable, iMLS(B) phenotype clone represented a substantial proportion (28.6%) of invasive erythromycin-resistant group A streptococcus (GAS) isolates in the Czech Republic during 2003. Clonal analysis of emm53 isolates between 2001 and 2004 revealed four pulsed-field gel electrophoresis (PFGE) patterns and two emm subtypes. Isolates produced identical PFGE patterns regardless of their invasiveness and/or tetracycline resistance. Multilocus sequence typing classified all isolates as ST340. An ST5 (emm83) isolate, a potential ancestor of ST340, was isolated in the Czech Republic from an impetigo patient in 1988. The Czech emm53/ST340 isolates shared only three of seven alleles with the original Lancefield emm53/ST11 isolate.

• MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální léková rezistence MeSH
• dítě MeSH
• dospělí MeSH
• erythromycin farmakologie   MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• pulzní gelová elektroforéza MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Streptococcus pyogenes klasifikace   účinky léků   genetika   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky MeSH
• erythromycin MeSH

A rapid and simple microdilution technique on 96-well microplate based on turbidimetry was optimized and validated for screening of antimicrobial activity against erythromycin-resistant bacterial strains of Streptococcus pyogenes and Staphylococcus simulans isolated from Finnish patients. Using S. pyogenes ATCC 12351 as reference strain the developed method was evaluated by reproducibility measurements and using parameters typically employed for screening methods, i.e. signal-to-background, signal-to-noise and a screening-window coefficient, the Z' factor. The method was further used for screening a group of natural compounds and their synthetic derivatives against resistant bacterial strains. Of these, octyl and dodecyl gallates, and usnic and ursolic acids were the most active. The described method is a rapid, homogeneous, cost-effective and easy-to-perform system for screening of new potential antimicrobial agents in drug discovery.

• MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• bakteriální léková rezistence * MeSH
• časové faktory MeSH
• erythromycin farmakologie   MeSH
• flavonoidy farmakologie   MeSH
• hydroxybenzoáty farmakologie   MeSH
• kumariny farmakologie   MeSH
• kyselina gallová analogy a deriváty   farmakologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti metody   normy   MeSH
• nefelometrie a turbidimetrie MeSH
• penicilin G farmakologie   MeSH
• Staphylococcus účinky léků   růst a vývoj   MeSH
• Streptococcus pyogenes účinky léků   růst a vývoj   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Finsko MeSH
• Názvy látek
• antibakteriální látky MeSH
• erythromycin MeSH
• flavonoidy MeSH
• hydroxybenzoáty MeSH
• kumariny MeSH
• kyselina gallová MeSH
• lauryl gallate MeSH Prohlížeč
• octyl gallate MeSH Prohlížeč
• penicilin G MeSH
• phenolic acid MeSH Prohlížeč

OBJECTIVES: The aim of the study was to evaluate the relationship between the development of the resistance of Streptococcus pyogenes strains to erythromycin and the utilisation of macrolides in the Olomouc region, Czech Republic. METHOD: During the period 1997-2001, data for utilisation of macrolides was obtained from the database of the regional General Health Insurance Company and expressed indefined daily doses per 1,000 patients per day. S. pyogenes strains were isolated from community patients suffering from acute bacterial tonsillitis. Their susceptibility to antibiotics was assessed by the disk diffusion method. RESULTS: Utilisation of macrolides increased by 13% in the period 1997-2001; their utilisation represented 11.40% of total antibiotic prescription in 1997 and 15.48% in 2001. Occurrence of erythromycin-resistant S. pyogenes strains increased significantly from 14% in 1997 to 32% in the year 2001 (P < 0.01). In 2000, macrolides consumption decreased non-significantly, but with no concomitant decrease in erythromycin-resistant S. pyogenes strains occurrence. Absolute susceptibility of S. pyogenes, the most important bacterial pathogen in community-acquired bacterial tonsillitis, to penicillin contrasts with increasing macrolide resistance. CONCLUSIONS: The study documents the influence of increased utilisation of macrolides on bacterial resistance. Penicillin should be a first-choice antibiotic in acute bacterial tornsillitis; macrolides should only be reserved for patients allergic to penicillins.

• MeSH
• antibakteriální látky farmakologie   terapeutické užití   MeSH
• bakteriální léková rezistence * MeSH
• časové faktory MeSH
• erythromycin farmakologie   terapeutické užití   MeSH
• hodnocení spotřeby léčiv statistika a číselné údaje   trendy   MeSH
• lidé MeSH
• mikrobiální testy citlivosti metody   MeSH
• Streptococcus pyogenes účinky léků   izolace a purifikace   MeSH
• streptokokové infekce farmakoterapie   mikrobiologie   MeSH
• tonzilitida farmakoterapie   mikrobiologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• antibakteriální látky MeSH
• erythromycin MeSH

The study of the prevalence of erythromycin resistance in 22 169 S. pyogenes strains in the Czech Republic in 1996-2003 on the background of rough data on the nationwide consumption of macrolide antibiotics confirmed that the exponential growth of resistance observed in 1998-2001 copied with a delay the rise in macrolide antibiotic consumption recorded in 1992-1995. The highest frequency of erythromycin resistance was found in 2001 (16.5%) with a subsequent decrease to 14.5% in 2002 and to 9.1% in 2003. The drop in resistance followed the stagnation in macrolide consumption and its decrease by 17% in 2002. Upward and downward trends in macrolide resistance in different regions and age groups copied the nationwide trends with some quantitative differences that could not be analyzed in view of the lack of detailed data on antibiotic consumption. A 99.5% concordance was found between the results of the phenotypic method and those of detection of genes coding for constitutive, inducible and efflux resistance to macrolide-lincosamide-streptograminB (MLSB) antibiotics. In 2001 when the highest erythromycin resistance was recorded in the Czech Republic, most of the tested strains (91.2%) showed resistance to all MLSB antibiotics, with macrolide efflux (susceptibility to lincosamides and 16-membered macrolides was conserved) being implicated in resistance of 8.8% of the strains only. In 2003, the number of erythromycin resistant strains decreased and the resistance mechanism was ascribed to macrolide efflux in 26.8% of them. Almost all of the strains with constitutive or induced MLSB resistance are also resistant to either tetracycline or bacitracin or both. In the light of S. pyogenes resistance to bacitracin, the bacitracin disk is not usable in preliminary identification any more.

• MeSH
• bakteriální léková rezistence MeSH
• dítě MeSH
• dospělí MeSH
• erythromycin farmakologie   MeSH
• lidé MeSH
• makrolidy farmakologie   MeSH
• mladiství MeSH
• předškolní dítě MeSH
• Streptococcus pyogenes účinky léků   genetika   MeSH
• streptokokové infekce mikrobiologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• předškolní dítě MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• erythromycin MeSH
• makrolidy MeSH

Results obtained in the first year of active surveillance of serious diseases caused by group A streptococci in the Czech Republic carried out within the Strep-EURO project are summarized. From January to December 2003, 28 Czech laboratories referred to the National Institute of Public Health 59 group A streptococcal strains isolated from invasive diseases meeting the Strep-EURO definition. At the same time, clinical-epidemiological data and information on the catchment area population were provided. For 2003, the total morbidity and case fatality rates were calculated to be 1.3/100,000 population and 13.5%, respectively. A high proportion (23.7%) of the 59 strains were of type emm 1, initially labeled M1. As many as 24.1%, 17.2% and 20.7% of the strains tested were resistant to erythromycin, clindamycin and tetracycline, respectively. The seemingly lower morbidity rate and higher case fatality rate from serious diseases caused by group A streptococci reported in the Czech Republic for 1994-1996, i.e. 0.4/100,000 and 46.5%, respectively, in comparison with the latest data can be explained by the use of softer international criteria for the Strep-EURO definition of invasive disease.

• MeSH
• dítě MeSH
• dospělí MeSH
• incidence MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• mladiství MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• prevalence MeSH
• rizikové faktory MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Streptococcus pyogenes * účinky léků   MeSH
• streptokokové infekce epidemiologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH