Acta microbiologica et immunologica Hungarica最新文献

Haemophilus influenzae is one of the main bacteria responsible for otitis media (OM) among children worldwide. We aimed to estimate the distribution of encapsulated and non-capsulated variants (NTHi), biotypes, antibiotic susceptibility, and molecular epidemiology of H. influenzae isolates recovered from pediatric OM cases in Bulgaria.Capsule detection was done by PCR for bexB gene, absent in NTHi. All encapsulated strains were subjected to PCR serotyping. MIC susceptibility testing was performed according to the criteria of EUCAST. MLST was conducted for all 71 OM isolates.The capsule detection and PCR - serotyping disclosed a predominance of NTHi (90.1%) and a few "a", "f", and "c" types. Biotype I was the most widespread (42.3%). β-lactam resistance was found in 35.2% of the isolates. MLST represented heterogenic population structure, whereas the most represented clonal complexes belonged to ST-3, ST-57, ST-105, and ST-1426. 42.3% of the STs showed relatedness to globally represented clones, and 11.3% displayed affiliation to international type 2.Most of the H. influenzae isolates recovered from children with otitis media were non-typable strains from biotype I. The examined population structure was genetically diverse, with a predominance of international type 2 isolates.

The intestinal microbiota is a microenvironment that has been the subject of studies for several decades. Over time, it has been reconsidered as a possible cofactor of multiple acute and chronic human diseases. In fact, alterations of the intestinal bacterial flora have been found in various neurological diseases. There are three modes of interaction between the intestinal microbiota and the gut-brain-axis: chemical signals, neural pathways and immune system. Even at the gastrointestinal level, the gut microbiota plays certainly an important role in the etiopathogenesis of chronic intestinal inflammatory diseases but also in irritable bowel syndrome. An important correlation has also been demonstrated with non-alcoholic fatty liver disease, as well as in other metabolic, cardiovascular and oncological diseases. Bacteria, viruses, fungi and various microorganisms that normally reside in our intestines can also be called into question as protective factors against these diseases. All this evidence leads researchers to consider the gut microbiota as a key element in the determination of aforementioned diseases. Therefore, it would be foreseeable in the future to associate the use of probiotics with the therapies used in the treatment of all these diseases. In this review we have condensed the main current knowledge regarding the link between the most frequent diseases and the gut microbiota.

This study aimed to investigate phenotypic and genotypic characteristics of carbapenem-resistant Enterobacterales isolates (CRE) at a tertiary laboratory in South Africa. A total of 99 CRE isolates were collected between 2019 and 2021. Carbapenemase production was tested using modified carbapenem inhibitory method. Colistin susceptibility testing was performed using the ComASP™ Colistin broth microdilution method. Conventional PCR assays were conducted for detection of mcr-1 gene and common carbapenemase genes (blaVIM, blaNDM, blaIMP, blaKPC, blaOXA-23, blaOXA-51 and blaOXA-48). Rep-PCR assay was conducted to determine the genetic relatedness of the study isolates. Majority of the isolates were Klebsiella pneumoniae (83%). Carbapenem resistant K. pneumoniae cluster was observed from ICU and surgical ward samples. Colistin resistance was observed in 13% (12/93) of the isolates namely, in 11 K. pneumoniae and one Enterobacter cloacae. The blaOXA-48 (65%) was the most prevalent gene detected followed by blaNDM (25%) and blaVIM (22%). Several K. pneumoniae isolates concomitantly carried multiple carbapenemase genes with one isolate carry up to 5 five genes blaVIM, blaNDM, blaOXA-48, blaOXA-23 and blaOXA-51. The mcr-1 gene was not detected in the isolates. Rep-PCR assay showed that most isolates matched cluster A (50%). The high prevalence of blaOXA-48, blaNDM and emerging colistin resistant isolates is of concern for patient management at this institution and needs close monitoring. Rep-PCR is a valuable tool in establishing infection clusters in resource-limited settings.

Antimicrobial resistance (AMR) poses a significant threat in veterinary medicine due to the excessive and inappropriate use of antimicrobial agents, compromising the effectiveness of these drugs. To combat AMR, the collection of data on the consumption of antibiotics is paramount, as there is a well-established connection between antibiotic use and AMR in both humans and food-producing animals. Hence, the current study aimed to generate measurable data concerning the sales patterns of antimicrobial drugs used in animal treatment in Montenegro over a five-year period (from 2017 to 2021). Furthermore, the study aimed to compare these sales figures with the overall sales of antimicrobial veterinary medicine products (AMVMPs) during the same period, with particular emphasis on the utilization of critically important antimicrobials (CIAs) for human use. Data on AMVMPs consumption from 2017 to 2021 were expressed in euros and were sourced from the Institute for Medicines and Medical Devices of Montenegro (CInMED) annual reports, complying with the regulatory framework of the Law on Medicines in this country. Research results indicate that the sales of AMVMPs increased from 2017 to peak in 2019, followed by a stable decline of 21.79% in 2021. However, the portion of selected CIAs AMVMPs in total sales experienced a minor decline from 2017 to 2019, followed by a noticeable 6.11% increase from 2019 to 2021. In order to address AMR challenges, these findings emphasize the importance of enhancing surveillance and monitoring of veterinary antimicrobial use, as well as CIAs for human use.

The prevalence of Streptococcus agalactiae infections in adult populations is increasing. The current study aimed to characterize the genetic features of S. agalactiae strains responsible for different infections. A cross-sectional study was performed on 65 S. agalactiae strains (30 invasive and 35 noninvasive) isolated from non-pregnant women. All S. agalactiae isolates were confirmed by atr and dltS PCR assays. Antibiotic susceptibility patterns were determined using the disk diffusion method. Biofilm production was investigated by microtiter plate assay. PCR was done to detect resistance determinants. Isolates were characterized using the multilocus sequence typing (MLST) method. cMLSB, iMLSB, and M phenotypes accounted for 47.7%, 30.8%, and 6.2%, respectively. MDR was detected in 15.4% of noninvasive and 44.6% of invasive isolates. MtP assay indicated that 80% of isolates were biofilm producers. Biofilm formation was common among noninvasive compared with invasive strains (94.3% versus 66.7%). tet (M) (46.2%) and erm (B) (69.2%) were the most prevalent tetracycline and macrolide-resistance genes. The most prevalent serotype was type III (50.8%), followed by Ia (18.4%), II (15.4%), V (12.3%), and IV (3.1%). The frequency of serotype III among biofilm producer strains (81.8%) was found to be significantly higher than that of non-producer isolates (18.2%) (P < 0.05). S. agalactiae was resolved within four clonal complexes, including CC19 (46.2%; in both invasive and noninvasive), followed by CC23 (30.8%; only noninvasive isolates), CC1 (15.4%; only noninvasive isolates) and CC17 (7.6%; only invasive isolates). The main sequence types (STs) found were ST19 (27.7%), ST17 (7.7%), ST27 (6.2%), and ST28 (4.6%) linked with invasive infections and ST23 (18.4%), ST933 (12.3%), ST644 (9.2%), ST19 (7.7%), ST1 (6.2%) found in noninvasive infections. The high prevalence of CC19 and CC23 clones among S. agalactiae strains reflects the emergence of these lineages as successful clones in Iran.

Increase in antibiotic resistance in Staphylococcus aureus isolated from ear infection is a serious public health problem. The objective of this investigation was to determine the antibacterial resistance profile and genetic variability of the S. aureus isolated from adult patients with otitis externa (OE) and otitis media (OM) infections, Tehran- Iran. The disk diffusion was employed to detect the susceptibility of 45 S. aureus strains. Biofilm production was evaluated by microtiter plate assay. Genetic diversity of the isolates was determined by staphylococcal cassette SCCmec, spa, and MLST techniques. Resistance to mupirocin and vancomycin were identified in 40 and 2.2% of isolates. Out of the 45 S. aureus isolates, 41 (91.2%) strains were considered as positive biofilm strains at different levels. According to our results, S. aureus isolated from OM (44.4%, 20/45) were including CC8/ST239-SCCmecIII corresponded to spa types t860, t030, t037, t234, t421 (70%, 14/20) and CC/ST30-SCCmecIV corresponded to spa types t605 and t019 (30%, 6/20) while S. aureus isolated from OE (55.6%, 25/45) were including CC/ST30-SCCmecIV corresponded to spa types t605, t345 and t1130 (52%, 13/25), CC/ST22-SCCmecIV corresponded to spa type t790 (20%, 5/25), CC8/ST8-SCCmecIV corresponded to spa type t008 (16%, 4/25), and CC/ST45-SCCmecIV corresponded to spa types t004 and t038 (12%, 3/25). This study highlighted genetic variability and strong biofilm formation ability among our isolates revealing its crucial role in enhancing the resistance of this bacteria to drugs. Thus, it is necessary to continue the epidemiological analysis to improve the control of ear infections related to S. aureus.