Insertion sequences (IS) represent mobile genetic elements that have been shown to be associated with bacterial evolution and adaptation due to their effects on genome plasticity. In Bordetella pertussis, the causative agent of whooping cough, the numerous IS elements induce genomic rearrangements and contribute to the diversity of the global B. pertussis population. Previously, we have shown that the majority of IS-specific endogenous promoters induce the synthesis of alternative transcripts and thereby affect the transcriptional landscape of B. pertussis. Here, we describe the regulatory RNA Rfi2, which is transcribed from the Pout promoter of the IS481 gene BP1118 antisense to the adjacent fim2 gene encoding the major serotype 2 fimbrial subunit of B. pertussis. Among the classical bordetellae, Rfi2 is unique to B. pertussis, suggesting its specific role in virulence. We show that Rfi2 RNA attenuates fim2 transcription and, consequently, the production of the Fim2 protein. Interestingly, the mutant that does not produce Rfi2 displayed significantly increased cytotoxicity towards human macrophages compared to the parental strain. This observation suggests that the Rfi2-mediated reduction in cytotoxicity represents an evolutionary adaptation of B. pertussis that fine-tunes its interaction with the human host. Given the immunogenicity of Fim2, we further hypothesize that Rfi2-mediated modulation of Fim2 production contributes to immune evasion. To our knowledge, Rfi2 represents the first functionally characterized IS element-driven antisense RNA that modulates the expression of a virulence gene.

• Klíčová slova
• Bordetella pertussis, antisense RNA, cytotoxicity towards macrophages, fimbriae serotype 2, insertion sequence, modulation of virulence,
• MeSH
• antigeny bakteriální MeSH
• antisense RNA * genetika   MeSH
• bakteriální fimbrie * genetika   metabolismus   MeSH
• Bordetella pertussis * genetika   MeSH
• faktory virulence rodu Bordetella genetika   MeSH
• lidé MeSH
• makrofágy imunologie   mikrobiologie   MeSH
• pertuse * mikrobiologie   MeSH
• promotorové oblasti (genetika) MeSH
• proteiny fimbrií * genetika   metabolismus   imunologie   MeSH
• regulace genové exprese u bakterií * MeSH
• séroskupina MeSH
• transpozibilní elementy DNA MeSH
• virulence MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny bakteriální MeSH
• antisense RNA * MeSH
• faktory virulence rodu Bordetella MeSH
• fim2 protein, Bordetella MeSH Prohlížeč
• proteiny fimbrií * MeSH
• transpozibilní elementy DNA MeSH

Infective endocarditis (IE) is a life-threatening disease, with its mortality rate varying depending on the infectious agent. Streptococci are among the most common causes of infective endocarditis. However, Streptococcus vestibularis has rarely been associated with human infections, typically affecting patients with underlying conditions such as immunosuppressive diseases, valve replacement, rheumatic heart disease, and hemodialysis. We present the case of a 26-year-old man who presented with fever, unanticipated weight loss, and fatigue. Although no typical risk factors for infective endocarditis were identified at admission, transesophageal echocardiography revealed a bicuspid aortic valve with calcification, paravalvular aortic abscess formation, and vegetations on the anterior leaflet of the mitral valve. Blood cultures grew S. vestibularis, which was initially sensitive to benzylpenicillin but developed emergent resistance on the third day of the antibiotic treatment. Subsequently, ceftriaxone therapy was initiated, and blood cultures became sterile on day 10. The patient eventually underwent aortic valve replacement. We report the first known case of native aortic and mitral valve endocarditis caused by S. vestibularis, accompanied by a paravalvular abscess around the native aortic valve, in a patient who had no typical risk factors for infective endocarditis, except for a bicuspid aortic valve.

• Klíčová slova
• Bicuspid aortic valves, Infective endocarditis, Periannular abscesses, Streptococcus vestibularis,
• MeSH
• aortální chlopeň * MeSH
• bakteriální endokarditida * diagnóza   mikrobiologie   komplikace   MeSH
• dospělí MeSH
• lidé MeSH
• mitrální chlopeň * MeSH
• Streptococcus * izolace a purifikace   MeSH
• streptokokové infekce * diagnóza   komplikace   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

OBJECTIVES: Pseudomonas aeruginosa (PA) is a common causative pathogen of pneumonia acquired in the intensive care unit (ICU). The aim of this study was to determine the incidence of PA ICU pneumonia (PAIP) and to quantify its independent association with PA colonization at different body sites. METHODS: Adult patients on mechanical ventilation at ICU admission were prospectively enrolled across 30 European ICUs. PA colonization in the perianal area and in the lower respiratory tract was assessed within 72 hours after ICU admission and twice weekly until ICU discharge. PAIP development was evaluated daily. Competing risk models with colonization as a time-varying exposure and ICU death and discharge as competing events were fitted and adjusted for confounders to investigate the association between PA carriage and PAIP. RESULTS: A total of 1971 subjects were enrolled. The colonization prevalence with PA in the first 72 hours of ICU admission was 10.4% (179 perianal and 51 respiratory), whereas the acquisition incidence during the ICU stay was 7.0% (158 perianal and 47 respiratory). Of the 43 (1.8%) patients who developed PAIP, 11 (25.6%) were PA colonized on admission and 9 (20.9%) acquired colonization before PAIP onset. Both perianal (adjusted subdistribution hazard ratio, 4.4; 95% CI, 1.7-11.6) and respiratory colonization (adjusted subdistribution hazard ratio: 4.6, 95% CI, 1.9-11.1) were independently associated with PAIP development. DISCUSSION: PAIP incidence was higher in PA colonized vs. non-colonized patients. Colonization of both the rectum and of the respiratory tract was associated with development of PAIP. The increased risk of PA colonization for subsequent infection provides an opportunity for targeted preventive interventions.

• Klíčová slova
• Colonization, Healthcare-associated infection, ICU-acquired pneumonia, Pseudomonas aeruginosa, VAP,
• MeSH
• dospělí MeSH
• incidence MeSH
• infekce spojené se zdravotní péčí epidemiologie   mikrobiologie   MeSH
• jednotky intenzivní péče * statistika a číselné údaje   MeSH
• lidé středního věku MeSH
• lidé MeSH
• přenašečství epidemiologie   mikrobiologie   MeSH
• prevalence MeSH
• prospektivní studie MeSH
• pseudomonádové infekce * epidemiologie   mikrobiologie   MeSH
• Pseudomonas aeruginosa * izolace a purifikace   MeSH
• senioři MeSH
• ventilátorová pneumonie epidemiologie   mikrobiologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH

The ApxIVA protein belongs to a distinct class of a "clip and link" activity of Repeat-in-ToXin (RTX) exoproteins. Along with the three other pore-forming RTX toxins (ApxI, ApxII and ApxIII), ApxIVA serves as a major virulence factor of Actinobacillus pleuropneumoniae, the causative agent of porcine pneumonia. The gene encoding ApxIVA is located on a bicistronic operon downstream of the orf1 gene and is expressed exclusively under in vivo conditions. Both ApxIVA and ORF1 are essential for full virulence of A. pleuropneumoniae, but the molecular mechanisms by which they contribute to the pathogenicity are not yet understood. Here, we provide a comprehensive structural and functional analysis of ApxIVA and ORF1 proteins. Our findings reveal that the N-terminal segment of ApxIVA shares structural similarity with colicin M (ColM)-like bacteriocins and exhibits an antimicrobial activity. The ORF1 protein resembles the colicin M immunity protein (Cmi) and, like Cmi, is exported to the periplasm through its N-terminal signal peptide. Additionally, ORF1 can protect bacterial cells from the antimicrobial activity of ApxIVA, suggesting that ORF1 and ApxIVA function as an antibacterial toxin-immunity pair. Moreover, we demonstrate that fetal bovine serum could elicit ApxIVA and ORF1 production under in vitro conditions. These findings highlight the coordinated action of various RTX determinants, where the fine-tuned spatiotemporal production of ApxIVA may enhance the fitness of A. pleuropneumoniae, facilitating its invasion to a resident microbial community on the surface of airway mucosa.

• Klíčová slova
• Actinobacillus pleuropneumoniae, Bacterial, Infectious Diseases, Pathogenesis, RTX proteins, Structural biology, Toxin-antitoxin system,
• MeSH
• Actinobacillus pleuropneumoniae * genetika   imunologie   MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální proteiny * genetika   metabolismus   imunologie   MeSH
• bakteriální toxiny genetika   metabolismus   imunologie   MeSH
• faktory virulence genetika   MeSH
• infekce bakteriemi rodu Actinobacillus mikrobiologie   veterinární   MeSH
• koliciny genetika   metabolismus   MeSH
• operon * MeSH
• prasata MeSH
• regulace genové exprese u bakterií MeSH
• virulence MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• ApxIVA protein, Actinobacillus pleuropneumoniae MeSH Prohlížeč
• bakteriální proteiny * MeSH
• bakteriální toxiny MeSH
• faktory virulence MeSH
• koliciny MeSH

OBJECTIVES: While the reported incidence of non-tuberculous mycobacterial (NTM) infections is increasing, the true prevalence remains uncertain due to limitations in diagnostics and surveillance. The emergence of rare and novel species underscores the need for characterization to improve surveillance, detection, and management. METHODS: We performed whole-genome sequencing (WGS) and/or targeted deep-sequencing using the Deeplex Myc-TB assay on all NTM isolates collected in Slovakia and the Czech Republic between the years 2019 to 2023 that were unidentifiable at the species level by the routine diagnostic line probe assays (LPA) GenoType CM/AS and NTM-DR. Minimal inhibitory concentrations against amikacin, ciprofloxacin, moxifloxacin, clarithromycin, and linezolid were determined, and clinical data were collected. RESULTS: Twenty-eight cultures from different patients were included, of which 9 (32.1%) met the clinically relevant NTM disease criteria. The majority of those had pulmonary involvement, while two children presented with lymphadenitis. Antimycobacterial resistance rates were low. In total, 15 different NTM species were identified, predominantly rare NTM like M. neoaurum, M. kumamotonense and M. arupense. Notably, clinically relevant M. chimaera variants were also identified with WGS and Deeplex-Myc TB, which, unlike other M. chimaera strains, appeared to be undetectable by LPA assays. Deeplex detected four mixed infections that were missed by WGS analysis. In contrast, WGS identified two novel species, M. celatum and M. branderi, which were not detected by Deeplex-Myc TB. Importantly, one of these novel species strains was associated with clinically relevant pulmonary disease. DISCUSSION: Our study demonstrates the clinical relevance of uncommon NTM and the effectiveness of targeted deep-sequencing combined with WGS in identifying rare and novel NTM species.

• Klíčová slova
• Diagnostics, Non-tuberculous mycobacteria, Novel species, Targeted next-generation sequencing, Whole-genome sequencing,
• MeSH
• antibakteriální látky * farmakologie   MeSH
• atypické mykobakteriální infekce * mikrobiologie   diagnóza   MeSH
• bakteriální léková rezistence MeSH
• dítě MeSH
• dospělí MeSH
• genotyp MeSH
• klinická relevance MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikrobiální testy citlivosti * MeSH
• mladiství MeSH
• netuberkulózní mykobakterie * účinky léků   genetika   izolace a purifikace   MeSH
• předškolní dítě MeSH
• sekvenování celého genomu * MeSH
• senioři MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Slovenská republika epidemiologie   MeSH
• Názvy látek
• antibakteriální látky * MeSH

Some scholars consider the Antonine Plague to have been a major disease outbreak in the 2nd century CE that caused a significant decline in the population of the Roman Empire. Although there is currently no molecular evidence of the specific pathogen, literary evidence indicates the parameters of the disease that it caused and how significant the impact on Roman society was. One way to advance the current discussion concerning the Antonine Plague's impact on the Roman Empire's population is to examine the currently available sources and comparatively model the spread of different pathogens in a specific location with known demographic data for the relevant period. To accomplish this, we developed a series of dynamic ordinary differential equation models of the spread of disease in Rome between 165 and 189 CE for several pathogens. We found that daily disease deaths in the final years of the pandemic were inconsistent with estimates reported in primary sources, suggesting that either (a) the impact of the Antonine Plague may have been exaggerated in the descriptions of ancient authors, or (b) the daily deaths in ca. 189 CE were caused by a different disease event than the Antonine Plague, or (c) seasonality might have been a significant factor changing the intensity of disease spread, with the population more severely affected during the winter months. Although none of the pathogens we analyzed emerged as the likely causative agent of the Antonine Plague, the models show that the overall mortality rate would have increased maximally by 7%. This result contradicts the mortality rate accepted by historians who defend the thesis of the significant impact of this epidemic on the demography of the Roman Empire.

• MeSH
• dějiny 17. století MeSH
• dějiny starověku MeSH
• epidemický výskyt choroby dějiny   MeSH
• lidé MeSH
• mor * dějiny   epidemiologie   MeSH
• Check Tag
• dějiny 17. století MeSH
• dějiny starověku MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• historické články MeSH
• srovnávací studie MeSH
• Geografické názvy
• Řím epidemiologie   MeSH

Urinary tract infections (UTIs) are one of the most common bacterial diseases both in communities and in hospitalized patients, and at the same, time they are one of the most common indications for the use of antibiotics. UTI guidelines are generally available nationally or internationally, but they do not address all aspects of UTI treatment for different patient cohorts, age, gender, or comorbidities. The aim of the study was to point out the importance of stratified cumulative antibiograms at the level of individual health care facilities and the significant differences between epidemiological data, not only at the national level, but also at the local level. Our study analyses data from 383 patients with UTIs from a hospital department, General University Hospital (GUH), and 272 patients from an outpatient medical facility, Urocentrum (UC). This analysis focuses on the most common UTI causative agent, Escherichia coli, its representation as the causative agent of UTI in patients with complicated acute cystitis (N30), and its representation in complicated acute cystitis in patients with prostate cancer (C61). In addition to the frequency of occurrence, a sub-analysis of the incidence of resistance of E. coli to commonly used antibiotics by age, gender, diagnosis, and medical facility was performed. Results: The most common causative agent of UTI was E. coli. In patients with N30, it was 70% in GUH and 54% in UC, but in oncological patients with UTI, it was only 39% and 35%, respectively. In patients with UTI in C61, there was a significant difference in susceptibility of E. coli between individual health care facilities. Lower resistance was found in UC opposite to GUH isolates in ampicillin, with 29.8% vs. 65%, p = 0.001; amoxicillin/clavulanic acid, with 8.5% vs. 30%, p = 0.01; with 2.1% vs. 17.5% in pivmecillinam, p = 0.01; with 10.6% vs. 37.5% in co-trimoxazole, p = 0.003; and ciprofloxacin, with 10.6% vs. 30%, p = 0.04. The study shows significant differences in the sensitivity of urinary E. coli isolates in patients in relation to age, gender, medical devices, and the presence of comorbidities.

• Klíčová slova
• Escherichia coli, antibiotics+, resistance, stratified cumulative antibiograms, urinary tract infections,
• MeSH
• antibakteriální látky * terapeutické užití   MeSH
• bakteriální léková rezistence MeSH
• dospělí MeSH
• Escherichia coli * účinky léků   izolace a purifikace   MeSH
• infekce močového ústrojí * farmakoterapie   mikrobiologie   epidemiologie   MeSH
• infekce vyvolané Escherichia coli farmakoterapie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikrobiální testy citlivosti * MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky * MeSH

Medical students are exposed to the hospital environment and patients during their studies, increasing the risk of exposure to virulent and antibiotic-resistant isolates of Staphylococcus aureus. The aim of the study is to determine the prevalence of Staphylococcus aureus among medical students who have varying levels of exposure to the hospital environment to provide valuable insights into the risk of colonization and transmission. Nasal swabs and fingerprints were obtained and cultured on a selective medium for staphylococci. The obtained isolates were confirmed as methicillin-sensitive S. aureus (MSSA) or methicillin-resistant (MRSA) using PCR. Antibiotic resistance, the presence of virulence genes including enterotoxin encoding genes, and spa typing were performed. Among pre-clinical students, MSSA was detected on the nose in 45.2% and on the fingerprints in 10.6% of the participants. Among clinical students, MSSA was detected on the nose in 42.0% and on the fingerprints in 25.4%. Only one MRSA isolate was obtained. Genes seg and sei were the most frequently detected in both student groups, with their presence in over 40% of isolates among clinical students. The eta and etb genes were mainly detected from the nose in both student groups. In pre-clinical students, S. aureus carrying eta gene occurred in 6.4% and etb in 8.5%. In clinical students, the occurrence was 5.1% for eta and 8.5% for etb. The tst gene was identified only in the nose and fingerprints of the clinical student group. The most frequently observed resistance was to clindamycin and erythromycin. In total 58 different spa types were identified. High rates of asymptomatic MSSA carriage were observed in both groups of medical students. Detected MSSA strains showed a high degree of genetic variability, with a number of them carrying the virulence and antibiotic resistance genes. Although students do not exhibit increased risk to their patient's, increased hygiene is required in asymptomatic carriage personnel. The overall prevalence of MRSA was low, with a minimal risk of spread.

• Klíčová slova
• Spa type, Staphylococcus aureus, Antibiotic resistance, MRSA, Medical students, Virulence genes,
• MeSH
• antibakteriální látky farmakologie   MeSH
• dospělí MeSH
• faktory virulence * genetika   MeSH
• lidé MeSH
• methicilin rezistentní Staphylococcus aureus genetika   izolace a purifikace   účinky léků   klasifikace   MeSH
• mikrobiální testy citlivosti MeSH
• mladý dospělý MeSH
• přenašečství * mikrobiologie   epidemiologie   MeSH
• prevalence MeSH
• stafylokokové infekce * mikrobiologie   epidemiologie   MeSH
• Staphylococcus aureus * genetika   izolace a purifikace   účinky léků   klasifikace   MeSH
• studenti lékařství * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• faktory virulence * MeSH

Brucellosis is one of the most important zoonoses worldwide, primarily affecting livestock but also posing a serious threat to public health. The major Brucella species are known to cause a feverish disease in humans with various clinical signs. These classical Brucella species are (re-)emerging, but also novel strains and species, some of them transmitted from rodents, can be associated with human infections. As a result of our review on rodent-borne brucellosis, we emphasise the need for more comprehensive surveillance of Brucella and especially Brucella microti in rodent populations and call for further research targeting the ecological persistence of rodent-associated Brucella species in the environment, their epizootic role in wild rodents and their virulence and pathogenicity for wildlife.

• Klíčová slova
• Brucella, public health risk, rodent, sapronosis, zoonosis,
• MeSH
• Brucella * izolace a purifikace   MeSH
• brucelóza * epidemiologie   veterinární   mikrobiologie   přenos   MeSH
• hlodavci * mikrobiologie   MeSH
• lidé MeSH
• veřejné zdravotnictví * MeSH
• zoonózy * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Syphilis, known as "the great mimicker," is caused by the spirochete Treponema pallidum and is characterized by a diverse array of clinical and histopathologic presentations. In secondary cutaneous syphilis, the most consistent morphological features include a superficial and deep perivascular infiltrate containing plasma cells, varying degrees of endothelial swelling, irregular acanthosis, elongation of rete ridges, a vacuolated pattern, and the presence of plasma cells. Although serologic tests are essential for definitive diagnosis, spirochetes can sometimes be directly identified in silver-stained tissue slides or through immunohistochemistry. Granuloma annulare is a relatively common, benign, self-limiting condition with 3 main variants: conventional, subcutaneous, and interstitial, each with distinct characteristics. In this study, we report 2 cases of cutaneous secondary syphilis with a striking granulomatous reaction pattern that closely mimics the interstitial variant of granuloma annulare. Owing to the severity of the tertiary stage of syphilis, distinguishing between these 2 entities is crucial.

• MeSH
• anulární granulom * patologie   diagnóza   mikrobiologie   MeSH
• diferenciální diagnóza MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• syfilis kožní patologie   diagnóza   mikrobiologie   MeSH
• syfilis * diagnóza   patologie   mikrobiologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH