Acta microbiologica et immunologica Hungarica最新文献

Prevalence of antibiotic resistant Helicobacter pylori was compared between 50 patients living outside the capital city and 50 matched pairs of capital city residents (CCRs). H. pylori isolates from 2018 to 2022 were included. Resistance rates in CCRs and those living elsewhere were 4.0 and 6.0% to amoxicillin, 48.0 and 42.0% to metronidazole, 30 and 30% to clarithromycin, and 4.0 and 4.0% to tetracycline, respectively. Levofloxacin resistance was higher (38.0%) in the capital city vs 20.0% (P = 0.047) in the country. Odd ratio for levofloxacin resistance between pair-matched groups was 2.45 (95% CI, OR 1.0-6.02, P value = 0.05) and relative risk for fluoroquinolone resistance was 1.90 (95% CI for RR 0.98-3.67) for CCRs vs residents in other regions. Resistance rates to levofloxacin and clarithromycin were worryingly high in our study, most probably due to the high quinolone consumption (2.86 DDD/day in 2017) in Bulgaria and the increase in macrolide, lincosamide and streptogramin consumption, especially of azithromycin, by >42% with the start of COVID-19 pandemic. Briefly, antibiotic resistance of H. pylori has a dynamic change, and it can display different patterns in certain geographic regions. The results imply that antibiotic consumption should be carefully controlled and unjustified use of levofloxacin should be restricted, especially in some large cities. Antibiotic policy should be further strengthened and regular monitoring of resistance in various geographic regions is needed for treatment optimization.

The present study aimed to explore the genotypic and phenotypic characteristics of biofilm formation in Bulgarian nosocomial Stenotrophomonas maltophilia isolates (n = 221) during the period 2011-2022, by screening for the presence of biofilm-associated genes (BAG) (spgM, rmlA and rpfF), their mutational variability, and assessment of the adherent growth on a polystyrene surface. The methodology included: PCR amplification, whole-genome sequencing (WGS) and crystal violet microtiter plate assay for biofilm quantification. The overall incidence of BAG was: spgM 98.6%, rmlA 86%, and rpfF 66.5%. The most prevalent genotype was spgM+/rmlA+/rpfF+ (56.1%), followed by spgM+/rmlA+/rpfF- (28.5%), and spgM+/rmlA-/rpfF+ (9.5%), with their significant predominance in lower respiratory tract isolates compared to those with other origin (P < 0.001). All strains examined were characterized as strong biofilm producers (OD550 from 0.224 ± 0.049 to 2.065 ± 0.023) with a single exception that showed a weak biofilm-forming ability (0.177 ± 0.024). No significant differences were observed in the biofilm formation according to the isolation source, as well as among COVID-19 and non-COVID-19 isolates (1.256 ± 0.028 vs. 1.348 ± 0.128, respectively). Also, no correlation was found between the biofilm amounts and the corresponding genotypes. WGS showed that the rmlA accumulated a larger number of variants (0.0086 per base) compared to the other BAG, suggesting no critical role of its product to the biofilm formation. Additionally, two of the isolates were found to harbour class 1 integrons (7-kb and 2.6-kb sized, respectively) containing sul1 in their 3' conservative ends, which confers sulfonamide resistance. To the best of our knowledge, this is the first study on S. maltophilia biofilm formation in Bulgaria, which also identifies novel sequence types (ST819, ST820 and ST826). It demonstrates the complex nature of this adaptive mechanism in the multifactorial pathogenesis of biofilm-associated infections.

Hands of healthcare workers play essential role in the spreading of antimicrobial-resistant microorganisms in and out of the healthcare settings. Less is known about the role of laboratory workers (LWs). The aim of our study was to evaluate the presence of biofilm-forming staphylococci on the surface of jewelry rings of LWs and their antimicrobial susceptibility pattern.A total of 79 LWs from eight different microbiology laboratories that process and analyze specimens from the tertiary care hospitals in Belgrade, Serbia participated in the study. The study was reviewed and approved by the institutional review boards at hospitals. Samples were taken after hand washing. Bacteria on LWs wedding rings were detected with the rolling method, and further analyzed in order to determine the number of colony forming unit (CFU) per ring, species of bacteria and their antimicrobial susceptibility pattern, methicillin resistance and biofilm-producing capacity in vitro.Staphylococci were recovered from 60.8% of wedding rings. All strains produced biofilm (25% weak, 56.2% moderate and 18.8% large amount), with significant difference between species (P < 0.001). Staphylococcus aureus and Staphylococcus epidermidis formed the largest amount of biofilm and had the largest number of CFU per ring. Staphylococci were most commonly resistant to penicillin (66.7%), tetracycline (50.0%), and erythromycin (45.8%); 41.7% of isolates was multidrug resistant and mecA gene was detected in five strains. All strains were susceptible to linezolid, vancomycin, teicoplanin and tigecycline.Staphylococci colonize LWs wedding rings, form biofilm on it, have multidrug resistant phenotype and/or carry mecA gene, representing a significant reservoir for the spreading of microorganisms and resistance. As far as we know, our study is the first that address this topic in laboratory workers.

The high demand for COVID-19 diagnosis overwhelmed reference hospitals. Regional laboratories had to incorporate molecular technology to respond to the emergency. This work described the implementation of molecular diagnostic tools and the detection of SARS-CoV-2, in a regional hospital with no previous experience, from October 2020 to March 2022. The laboratory structure was significantly modified. The staff grew from 3 to 4 clinical microbiologists, and from 7 to 17 laboratory technicians to provide 24/7 coverage. A total of 144,442 samples were processed during the period of study. The highest peaks were reached in July 2021 with 25,285 samples processed, and between December 2021 and January 2022, with 32,245. COVID-19 pandemic has represented not only the challenge, but the opportunity to introduce Nucleic Acid Amplification Techniques (NAAT) in inexperienced laboratories. These secondary settings have shown an extraordinary ability to adapt and cannot be left behind in the progress of diagnostic techniques.

Multidrug-resistant (MDR) Acinetobacter baumannii is a serious global health threat. Burn patients are at high risk to acquire A. baumannii infections from endogenous sources. This study evaluated carbapenem resistance and clonal relatedness of A. baumannii isolated from burn patients and healthcare workers (HCWs).The study was performed in 100 non-duplicated A. baumannii isolates from nasal and hand samples of hospitalized burn patients and HCWs in two hospitals of Iran from June 2020 to August 2021. Antimicrobial susceptibility testing was performed and carbapenemase genes were detected by PCR. Clonal relatedness of A. baumannii isolates was determined by two single-locus sequence-based typing of blaOXA-51-like and ampC and by multilocus sequence typing (MLST).All A. baumannii isolates were found to be MDR while susceptible to colistin. The intI1, conserved segments of class 1 integron (intI1 CS), blaIMP, blaVIM, blaOXA-51-like, and blaOXA-23-like, genes were detected in 32.5%, 29.1%, 36%, 95.3%, 100%, 100%; and 14.3%, 14.3%, 21.4%, 92.9%, 100%, and 85.7% of isolates from patients and from healthcare workers, respectively. The blaOXA-58, and blaOXA-143 were not detected among the isolates. Using dual-locus blaOXA-51-like and ampC sequence-based typing (SBT), the isolates obtained from nasal samples of burn patients were grouped into 3 clusters including blaOXA-317, blaADC-88 (72.1%); blaOXA-64, ampC-25 (18.6%); and blaOXA-69, ampC-1 (9.3%). While only allele type blaOXA-317, blaADC-88 was determined among isolates from HCWs. MLST results showed A. baumannii ST136, ST25, and ST1 from burn patients. However, A. baumannii strains from HCWs belonged to ST136. Our findings indicate high prevalence of globally spreading of MDR A. baumannii ST136 carrying blaOXA-23-like from nasal and hand samples of burn patients and HCWs.

Escherichia coli ST131 is a pandemic clone with high antibiotic resistance, and it is a major causative agent of urinary tract infection (UTI) and bloodstream infections. This study evaluated the distribution and expression of virulence genes and genotyping of E. coli O25b/ST131 by Multi-locus variable number tandem repeat analysis (MLVA) method among UTI in patients at Tehran hospitals, Iran.A total of 107 E. coli isolates were collected from UTI patients. Polymerase chain reaction (PCR) amplification of the pabB gene was used to identify E. coli O25b/ST131 and the prevalence of sat and hlyA virulence genes was also analyzed. The microtiter method quantified biofilm formation ability in E. coli O25b/ST131. The Real-Time PCR (qRT-PCR) was performed to evaluate the expression of sat and hlyA genes. Finally, MLVA was performed for E. coli O25b/ST131 genotyping by targeting seven tandem repeats. SPSS-16 software was used for statistical analysis. Molecular study showed that 71% of isolates carried the pabB gene and were considered E. coli O25b/ST131 strains. Also, 45.8% and 17.8% of isolates carried sat and hlyA genes, respectively. The 57.9% isolates had biofilm formation ability. Expression of the studied virulence genes showed an increase in strong biofilm producing E. coli O25b/ST131 strains. A total of 76 (100%) E. coli O25b/ST131 strains were typed by the MLVA method.High prevalence of E. coli O25b/ST131 isolates in UTI patients can be a serious warning to the treatment due to the high antibiotic resistance rate, expression of virulence genes, and biofilm formation.

SARS-CoV-2 virus was initially identified in Wuhan, China, in December 2019 and a global pandemic was declared in March 2020 by World Health Organization. COVID-19 disease is characterized with severe pneumonia and hypoxemia, especially in the elderly population. The elderly population was primarily vaccinated with CoronaVac, which is a whole virion inactivated vaccine (Sinovac Biotech, China) in Turkey. This study aimed to investigate the association of viral load and laboratory parameters with the severity of the disease and vaccination status in elderly (older than 60 years old) COVID-19 patients. The age range of the patients was 61-97 years old with a mean of 71.80. Vaccinated patients had a lower viral load (P = 0.253) in nasopharyngeal swabs during breakthrough COVID-19 infection compared to unvaccinated ones and were hospitalized for a shorter period of time in hospital wards (P = 0.035). A lower number of patients were vaccinated in both moderate (n = 33, 29.20%) and severe/critical group (n = 46, 34.07%) (P = 0.412). Only 17 (32.08%) vaccinated patients were hospitalized in an intensive care unit (ICU), whereas 36 (67.92%) of the ICU patients were unvaccinated (P = 0.931). Severe/critical patients had higher c-reactive protein (CRP), platelet-to-lymphocyte ratio (PLR), fibrinogen, ferritin, and lactate dehydrogenase (LDH) levels compared to the moderate group on the admission day (P < 0.05). Our study suggested that elderly patients vaccinated with CoronaVac had a shorter stay in hospitals and according to our results CRP, PLR, fibrinogen, ferritin, and LDH levels could be used to determine the severity of the infections.

We investigated respiratory pathogens among ill Hajj pilgrims from Marseille. We also discuss the potential role of point-of-care (POC) rapid molecular diagnostic tools for this purpose. Clinical data were collected using a standardised questionnaire. Influenza A and B viruses, human rhinovirus and human coronaviruses, Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae and Klebsiella pneumoniae were investigated using real-time PCR in respiratory samples obtained during travel, at the onset of symptoms. 207 participants were included. A cough, expectoration, rhinitis and a sore throat were the most frequent respiratory symptoms, followed by loss of voice and dyspnoea. 38.7% and 25.1% of pilgrims reported a fever and influenza-like symptoms, respectively. 59.4% pilgrims received antibiotics. Rhinovirus (40.6%) was the most frequent pathogen, followed by S. aureus (35.8%) and H. influenzae (30.4%). Virus and bacteria co-infections were identified in 28.5% of participants. 25.1% pilgrims who were positive for respiratory bacteria did not receive antibiotic treatment. In the context of the Hajj pilgrimage, it is important to detect infections that can be easily managed with appropriate treatment, and those that can affect prognosis, requiring hospitalisation. POC rapid molecular diagnostic tools could be used for patient management at small Hajj medical missions and to rationalise antibiotic consumption among Hajj pilgrims.

In this study we report the whole genome sequencing (WGS) based analysis of blood-borne Campylobacter fetus subsp. fetus MMM01 isolated from a diabetic patient to obtain deeper insights in to the virulence and host adaptability. The sequenced genome of C. fetus subsp. fetus MMM01 along with reference genomes retrieved from NCBI was subjected to various in-silico analysis including JSpecies, MLST server, PATRIC server, VFanalyzer, CARD, PHASTER to understand their phylogenetic relation, virulence and antimicrobial resistance profile. The genome had a size of 1,788,790 bp, with a GC content of 33.09%, nearly identical to the reference strain C. fetus subsp. fetus 82-40. The MLST based phylogenetic tree constructed revealed the polyphyletic branching and MMM01 (ST25) was found to be closely related to ST11, both belong to the sap-A serotype which are more common in human infections. VFanalyzer identified 88 protein-coding genes coding for several virulence factors including Campylobacter adhesion to fibronectin, flagellar apparatus, cytolethal distending toxin operons and Campylobacter invasion antigen proteins which enhance the virulence of bacteria along with resistance genes against antibiotics including fluoroquinolone, chloramphenicol, tetracycline, and aminoglycoside in MMM01, which points to enhanced survival and pathogenicity of this zoonotic pathogen. It was interesting to find that MMM01 lacked FGI-II island found in most of the clinical isolates, which encoded CRISPR Cas and prophage II regions. More details about the complexity and evolution of this zoonotic pathogen could be learned from future studies that concentrate on comparative genome analysis using larger genome datasets.

We aimed to compare vaccinated and unvaccinated patients hospitalized with COVID-19 in terms of disease severity, need for intensive care unit (ICU) admission, and death. In addition, we determined the factors affecting the COVID-19 severity in vaccinated patients. Patients aged 18-65 years who were hospitalized for COVID-19 between September and December 2021 were retrospectively analyzed in three groups: unvaccinated, partially vaccinated, and fully vaccinated.A total of 854 patients were included. Mean age was 47.9 ± 10.6 years, 474 patients (55.5%) were male. Of these, 230 patients (26.9%) were fully vaccinated, 97 (11.3%) were partially vaccinated, and 527 (61.7%) were unvaccinated. Of the fully vaccinated patients, 67% (n = 153) were vaccinated with CoronaVac and 33% (n = 77) were vaccinated with Pfizer-BioNTech. All patients (n = 97) with a single dose were vaccinated with Pfizer-BioNTech. One hundred thirteen (13.2%) patients were transferred to ICU. A hundred (11.7%) patients were intubated and 77 (9.0%) patients died. Advanced age (P = 0.028, 95% CI = 1.00-1.07, OR = 1.038) and higher Charlson Comorbidity Index (CCI) (P < 0.001, 95% CI = 1.20-1.69, OR = 1.425) were associated with increased mortality, while being fully vaccinated (P = 0.008, 95% CI = 0.23-0.80, OR = 0.435) was associated with survival in multivariate analysis. Full dose vaccination reduced the need for ICU admission by 49.7% (95% CI = 17-70) and mortality by 56.5% (95% CI = 20-77). When the fully vaccinated group was evaluated, we found that death was observed more frequent in patients with CCI>3 (19.1 vs 5.8%, P < 0.01, OR = 3.7). Therefore, the booster vaccine especially in individuals with comorbidities should not be delayed, since the survival expectation is low in patients with a high comorbidity index.