Jan Tkadlec

Dr. Jan Tkadlec


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2019 in Journal of Microbiological Methods
Verified
Journal Article
Closed access
HKHana Kotková
Hana Kotková
MCMarie Cabrnochová
Marie Cabrnochová
ILIrena Lichá
Irena Lichá
JTJan Tkadlec
Jan Tkadlec
LFLibor Fila
Libor Fila
OMOto Melter
Oto Melter

4 March 2021 in Antibiotics
Verified
Journal Article
Open access
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JTJan Tkadlec
Jan Tkadlec
AKAlzbeta Kalova
Alzbeta Kalova
MBMarie Brajerova
Marie Brajerova
TGTereza Gelbicova
Tereza Gelbicova
RKRenata Karpiskova
Renata Karpiskova
MKMarcela Krutova
Marcela Krutova
Background: In order to estimate the prevalence of plasmid borne colistin resistance and to characterize in detail the mcr-positive isolates, we carried out a sentinel testing survey on the intestinal carriage of plasmid-mediated colistin-resistant Enterobacteriaceae in hospitalized patients. Methods: Between June 2018 and September 2019, 1922 faecal samples from hospitalised patients were analysed by selective culture in presence of colistin (3.5 mg/L), and in parallel by direct detection of the mcr-1 to mcr-8 genes by qPCR. The mcr-positive isolates were characterised by whole-genome sequencing. Results: The prevalence of the mcr-1 gene was 0.21% (n = 4/1922); the mcr-2 to 8 genes were not detected. The mcr-1 gene was found to be localised in the IncX4 (n = 3) and IncHI2 (n = 1) plasmid type. One Escherichia coli isolate was susceptible to colistin due to the inactivation of the mcr-1 gene through the insertion of the IS2 element; however, the colistin resistance was inducible by culture in low concentrations of colistin. One human mcr-1 positive E. coli isolate was related genetically to the mcr-1 E. coli isolate derived from turkey meat of Czech origin. Conclusions:mcr-mediated colistin resistance currently poses little threat to patients hospitalised in Czech healthcare settings. The presence of the mcr-1 gene in the human population has a possible link to domestically produced, retail meat.

16 June 2021 in Microbiologyopen
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Journal Article
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PDPavel Drevinek
Pavel Drevinek
JHJakub Hurych
Jakub Hurych
MAMilena Antuskova
Milena Antuskova
JTJan Tkadlec
Jan Tkadlec
JBJan Berousek
Jan Berousek
EBEliska Bebrova
Eliska Bebrova
In the microbiological diagnosis of bloodstream infections (BSI), blood culture (BC) is considered the gold standard test despite its limitations such as low sensitivity and slow turnaround time. A new FDA‐cleared and CE‐marked platform utilizing magnetic resonance to detect amplified DNA of the six most common and/or problematic BSI pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli; referred to as ESKAPEc) is available and may shorten the time to diagnosis and potentially improve antimicrobial utilization. Whole blood samples from hospitalized patients with clinical signs of sepsis were analyzed using the T2Bacteria Panel (T2Biosystems) and compared to simultaneously collected BC. Discrepant results were evaluated based on clinical infection criteria, combining supporting culture results and the opinion of treating physicians. A total of 55 samples from 53 patients were evaluated. The sensitivity and specificity of the T2Bacteria panel was 94% (16 out of 17 detections of T2Bacteria‐targeted organisms) and 100%, respectively, with 36.4% (8 of 22) causes of BSI detected only by this method. The T2Bacteria Panel detected pathogens on average 55 hours faster than standard BC. In our study, 9 of 15 patients with positive T2Bacteria Panel results received early‐targeted antibiotic therapy and/or modification of antimicrobial treatment based on T2Bacteria Panel findings. Given the high reliability, faster time to detection, and easy workflow, the technique qualifies as a point‐of‐care testing approach.

29 October 2020 in Journal of Antimicrobial Chemotherapy
Verified
Journal Article
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JTJan Tkadlec
Jan Tkadlec
VCVaclav Capek
Vaclav Capek
MBMarie Brajerova
Marie Brajerova
ESEva Smelikova
Eva Smelikova
OMOto Melter
Oto Melter
MKMarcela Krutova
Marcela Krutova
To gain data on the current molecular epidemiology and resistance of MRSA in the Czech Republic. Between September 2017 and January 2018, a total of 441 single-patient MRSA isolates were collected from 11 Czech hospitals and analysed by spa typing, SCCmec typing, antibiotic susceptibility testing, detection of the PVL toxin and the arcA gene. Of all MRSA isolates, 81.41% (n = 359) belonged to the CC5-MRSA clone represented by the spa types t003 (n = 136), t586 (n = 92), t014 (n = 81), t002 (n = 20) and other spa types (n = 30); a majority of the CC5 isolates (n = 348, 96.94%) carried SCCmec type II. The occurrence of CC5-MRSA was more likely in older inpatients and associated with a healthcare origin (P < 0.001). The CC5-MRSA isolates were resistant to more antimicrobial drugs compared with the other MRSAs (P < 0.001). Interestingly, t586 was detected in blood samples more often than the other spa types and, contrary to other spa types belonging to CC5-MRSA, t586 was not associated with patients of advanced age. Other frequently found lineages were CC8 (n = 17), CC398 (n = 11) and CC59 (n = 10). The presence of the PVL was detected in 8.62% (n = 38) of the MRSA isolates. The healthcare-associated CC5-MRSA-II lineage (t003, t586, t014) was found to be predominant in the Czech Republic. t586 is a newly emerging spa type in the Czech Republic, yet reported rarely in other countries. Our observations stress the need for MRSA surveillance in the Czech Republic in order to monitor changes in MRSA epidemiology.

7 February 2020 in Microbiologyopen
Verified
Journal Article
Open access
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JTJan Tkadlec
Jan Tkadlec
EBEliska Bebrova
Eliska Bebrova
JBJan Berousek
Jan Berousek
TVTomas Vymazal
Tomas Vymazal
JAJaroslava Adamkova
Jaroslava Adamkova
PDPavel Drevinek
Pavel Drevinek
Fast and accurate detection of causative agents of bloodstream infections remains a challenge of today's microbiology. We compared the performance of cutting‐edge technology based on polymerase chain reaction coupled with electrospray ionization‐mass spectrometry (PCR/ESI‐MS) with that of conventional broad‐range 16S rRNA PCR and blood culture to address the current diagnostic possibilities for bloodstream infections. Of 160 blood samples tested, PCR/ESI‐MS revealed clinically meaningful microbiological agents in 47 samples that were missed by conventional diagnostic approaches (29.4% of all analyzed samples). Notably, PCR/ESI‐MS shortened the time to positivity of the blood culture‐positive samples by an average of 34 hr. PCR/ESI‐MS technology substantially improved current diagnostic tools and represented an opportunity to make bloodstream infections diagnostics sensitive, accurate, and timely with a broad spectrum of microorganisms covered.

30 August 2024 in Journal of Antimicrobial Chemotherapy
Verified
Journal Article
Open access
PDF file
APAneta Papouskova
Aneta Papouskova
ZDZuzana Drabkova
Zuzana Drabkova
MBMarie Brajerova
Marie Brajerova
MKMarcela Krutova
Marcela Krutova
ACAlois Cizek
Alois Cizek
JTJan Tkadlec
Jan Tkadlec
We performed a retrospective analysis of MRSA isolates collected at the university equine clinic including clinical isolates from 2008 to 2021 and screening environmental, equine and personnel isolates from 2016. Screening and clinical samples were cultured on Brilliance MRSA 2 and Columbia agar (Oxoid), respectively, with enrichment for environmental samples. Antimicrobial susceptibility was assessed by disc diffusion. All the isolates were characterized by spa typing. Eighteen selected isolates were subjected to WGS with subsequent wgMLST clonal analysis. Among 75 MRSA isolates, five spa types were identified, the majority (n = 67; 89.33%) was t011. All isolates were resistant to cefoxitin and ampicillin and carried the mecA gene. In addition, the isolates were resistant to tetracycline (n = 74; 98.67%), gentamicin (n = 70; 93.33%), enrofloxacin (n = 54; 72.00%), sulfamethoxazole-trimethoprim (n = 5; 6.67%) and lincomycin (n = 3; 4.00%) with corresponding genetic markers for the resistance detected in the sequenced isolates. All 18 sequenced isolates belonged to ST398, 16 carried SCCmec type IVa and two carried SCCmec type Vc (5C2&5). Further, isolates carried aur, hlgA, hlgB and hlgC virulence genes, and five isolates carried sak and scn genes, which are part of the immune evasion cluster. Close genetic relatedness was found between isolates from the staff of the clinic and clinical samples of horses. Repeated introduction and long-term persistence of the equine LA-MRSA subclone (ST398-MRSA-IVa/Vc(5C2&5), t011) among the infected horses at the equine clinic with the colonization of personnel, and the environment contamination that might contribute to transmission were observed.