Acta Microbiologica Et Immunologica Hungarica[JOURNAL]
Sun
200 papers
Role of oral microbiota in irreversible pulpitis - Current strategies and future perspectives.
Shetty P, Shetty S, Rai P … +2 more , Kumar BK, Bhat R
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37505986 · Publisher ↗
Irreversible pulpitis is an inflammation of the tooth pulp caused by an opportunity-driven invasion of the pulp space by oral microbiota typically prevalent in the oral cavity. Microbial organisms are extensively recogni...
Irreversible pulpitis is an inflammation of the tooth pulp caused by an opportunity-driven invasion of the pulp space by oral microbiota typically prevalent in the oral cavity. Microbial organisms are extensively recognised to be the fundamental cause of endodontic infections and treatment failures. Previously, bacterial species responsible for these infections were largely recognised using conventional microbial culture techniques, lending credence to the widely held belief that anaerobic Gram-negative bacteria frequently enter the pulp space and trigger endodontic infections. The advent of novel technologies grants the advantage of detecting and studying microbial populations via an amalgamation of the modern "Omics" techniques and meticulous bioinformatics analysis, additionally detecting the metatranscriptome, metaproteome and metabolome along with the metagenome. Amongst these analytical strategies, metagenomic analyses are essentially pragmatic for investigating the oral microbiome. Metagenomics favor not only assessment of microbial composition in diseased conditions, but also contributes to detection of novel, potentially pathogenic species inclusive of non-viable bacteria. The present review describes current knowledge of root canal microbiome, including its composition and functional attributes, the novel strategies available for detection of microbiome as well as challenges associated and provides some crucial pointers for areas of future research.
Molecular epidemiology and characterization of endemic, epidemic and imported hepatitis A virus (HAV) strains in Hungary (2003-2022).
Reuter G, Boros Á, Pankovics P
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37490367 · Publisher ↗
Hepatitis A virus (HAV) is one of the most important etiological agents of acute viral hepatitis but comprehensive molecular epidemiological study with chrono-phylogeographical data are not available from Hungary.Between...
Hepatitis A virus (HAV) is one of the most important etiological agents of acute viral hepatitis but comprehensive molecular epidemiological study with chrono-phylogeographical data are not available from Hungary.Between 2003 and 2022, a total of 8,307 HAV infections were registered officially in Hungary of which 400 (4.8%) HAV IgM antibody-positive serum samples were collected countrywide. HAV genomic RNA was successfully detected in 216/400 (54%) sera by RT-PCR subsequently confirmed by sequencing. The complete nucleotide sequences of VP1 region were determined in 32 representative HAV strains. Based on the sequence analysis, 150 (69.4%) strains were characterized as HAV sub-genotype IA and 66 (30.6%) as sub-genotype IB, respectively. Based on the combined epidemiological and molecular data, epidemic, endemic, and imported HAV strains were also characterized. The first two registered countrywide outbreaks started among men-sex-with men (MSM) in 2011 (sub-genotype IA) and 2021 (sub-genotype IB), the continuously circulating endemic/domestic HAV strain (sub-genotype IA) in East Hungary and the travel-related sub-genotype IB strains from Egypt should be highlighted. All HAV strains are deposited in the HAVNET database (https://www.rivm.nl/en/havnet).In this 20-year-long comprehensive molecular epidemiological study, we report the genetic characterization and geographic distribution of endemic, epidemic and imported HAV strains for the first time in Hungary with continuous co-circulation of sub-genotypes IA and IB HAV strains since 2003. These data provide basic information about the HAV situation in the country in an international context and can promote more effective national public health intervention strategies for the prevention of HAV transmissions and infections.
Detection of carbapenem resistant Pseudomonas aeruginosa co-harboring blaVIM-2 and blaGES-5 in burn patients.
Hmissi S, Raddaoui A, Frigui S … +4 more , Abbassi MS, Achour W, Chebbi Y, Thabet L
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37490366 · Publisher ↗
Pseudomonas aeruginosa is one of the major infectious agents in burn patients. Globally, high rates of antimicrobial resistance in P. aeruginosa have been reported, which is a cause of concern. The objective of this stud...
Pseudomonas aeruginosa is one of the major infectious agents in burn patients. Globally, high rates of antimicrobial resistance in P. aeruginosa have been reported, which is a cause of concern. The objective of this study was to determine the rate of resistance to carbapenems in P. aeruginosa isolates recovered from burn patients in Tunisia, to search genes encoding for carbapenemases and to determine their epidemiological markers (serotypes). A retrospective study was conducted in the Burn Intensive Care Unit (BICU) of the Trauma and Burn Centre of Ben Arous, Tunisia, and P. aeruginosa isolates collected from burn patients, from January to December 2018 were investigated. Carbapenemase screening was performed by Carbapenem Inactivation Method (CIM) and by EDTA-disk test for all carbapenem resistant isolates. Genes encoding carbapenemases (blaVIM, blaIMP, blaGES, blaNDM, and blaKPC) were investigated by PCR and selected carbapenemase genes were sequenced. During the study period, 104 non duplicated P. aeruginosa isolates were recovered. Most of them were isolated from skin samples (45.1%) and blood culture (22.1%) and belonged to O:11 (19.2%), O:12, and O:5 (12.5%, each) serotypes. High rates of resistance were observed for carbapenems (64.4%). Among the 67 carbapenem resistant isolates, 58 (86.5%) harbored blaVIM gene and 55 (82%) blaGES gene; in addition, 48 (71.6%) co-harbored blaVIM and blaGES genes. After sequencing, the blaVIM-2 and blaGES-5 gene variants were identified in seven randomly selected isolates. To the best of our knowledge, this is the first description of P. aeruginosa simultaneously harboring blaVIM-2 and blaGES-5 genes.
Emergence of colistin resistant Acinetobacter baumannii clonal complex 2 (CC2) among hospitalized patients in Iran.
Hajihashemi B, Abbasi A, Shokri D
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37486821 · Publisher ↗
Acinetobacter baumannii is a major causative agent of serious nosocomial infections. This study was carried out to investigate the molecular characterization of colistin resistant isolates of A. baumannii from hospitaliz...
Acinetobacter baumannii is a major causative agent of serious nosocomial infections. This study was carried out to investigate the molecular characterization of colistin resistant isolates of A. baumannii from hospitalized patients, based on multilocus sequence typing (MLST). A cross-sectional study was conducted to collect A. baumannii from clinical samples in Isfahan from 2021 to 2022. Isolates were identified as A. baumannii using biochemical tests and PCR of blaOXA-51. Antibiotic susceptibility testing was carried out using the Kirby-Bauer method and minimum inhibitory concentration (MIC) values were determined for colistin. Additionally, MLST was performed according to the Pasteur scheme to assess the relationship between colistin resistant A. baumannii. A total of 70 non-repetitive A. baumannii isolates were obtained from different clinical samples. MIC results showed that seven A. baumannii isolates were resistant to colistin. The antibiotic susceptibility pattern revealed that all seven colistin resistant strains were resistant to all tested antibiotics. Based on MLST analysis, the colistin resistant isolates were assigned to five unique STs namely, ST2 (3; 42.9%) followed by ST78 (1; 14.3%), ST1077 (1; 14.3%), ST415 (1; 14.3%) and ST391 (1; 14.3%). Among them ST2, ST391 and ST415 belong to clonal complex 2. Colistin resistant A. baumannii ST2 is the main circulating clone in clinical settings in Iran, but additionally ST415, ST391, and ST1077 are found for the first time in our country. Intensive control procedures and strict adherence to surveillance programs are recommended to decrease the spread of carbapenem and colistin resistant A. baumannii strain.
Analysis of NDM-1 and IMP-8 carbapenemase producing Raoultella planticola clinical isolates.
Wang Q, Wang X, Chen C … +3 more , Zhao L, Ma J, Dong K
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37478009 · Publisher ↗
Object of our study was to analyze the carriage of resistance genes in carbapenem-resistant Raoultella planticola (CRRP) by whole genome sequencing (WGS). Three strains of CRRP (named WF0027, WF3597 and WF3648) were coll...
Object of our study was to analyze the carriage of resistance genes in carbapenem-resistant Raoultella planticola (CRRP) by whole genome sequencing (WGS). Three strains of CRRP (named WF0027, WF3597 and WF3648) were collected for clinical analysis and susceptibility of antimicrobial agents was determined. The WGS of three strains was done by Illumina platform and strain identification was performed by average nucleotide identity, and the antibiotic resistance genes carried by the three strains were detected by ABRicate software. Whole genome data of 46 CRRP strains were downloaded from the National Center for Biotechnology Information (NCBI) database, and the evolutionary tree was constructed by genomic single nucleotide polymorphism together with this study strains. Antimicrobial susceptibility testing revealed that WF3597 and WF3648 were susceptible to tigecycline and colistin, while exhibited resistance to 24 antimicrobial agents. WF0027 was resistant to 18 antimicrobial agents. A total of 25 resistance genes were identified using ABRicate software. WF0027 carried blaIMP-8, whereas WF3597 and WF3648 carried blaNDM-1 carbapenem resistance gene. As predicted by the PlasmidFinder, WF3597 and WF3648 carried one plasmid IncFII(p14)_1_p14, whereas WF0027 carried five plasmids. Evolutionary tree results show all strains are clustered into six groups, the strains WF3597 and WF3648 belonged to the same evolutionary group (E clade) and WF0027 belonged to the F clade. Three CRRP strains in our study carried carbapenem resistance genes (blaNDM-1 or blaIMP-8) and were resistant to multiple antimicrobial agents, posing a significant challenge for clinical treatment.
Clinical and microbiological characteristics of nocardiosis: A 5-year single-center study in Crete, Greece.
Maraki S, Mavromanolaki VE, Kasimati A … +2 more , Stafylaki D, Scoulica E
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37459246 · Publisher ↗
Nocardiosis is a rare disease affecting both immunocompromised and immunocompetent hosts, presented in various clinical forms ranging from localized to disseminated infection. Aim of the present study was to investigate...
Nocardiosis is a rare disease affecting both immunocompromised and immunocompetent hosts, presented in various clinical forms ranging from localized to disseminated infection. Aim of the present study was to investigate the clinical and microbiological characteristics of nocardiosis, antimicrobial resistance profiles, treatment, and outcomes of Nocardia infection over the last 5 years at our institution. The medical records and microbiological data of patients affected by nocardiosis and treated at the university hospital of Heraklion, Crete, Greece, between 2018 and 2022, were retrospectively analyzed. The isolates were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and through sequencing of 16S rRNA. Antimicrobial susceptibility for 17 agents was determined by E-test and results were interpreted according to CLSI guidelines. Among the 28 Nocardia isolates, eight species were identified, with Nocardia brasiliensis being the most prevalent (32.1%), followed by Nocardia otitidiscaviarum (25%), and Nocardia farcinica (14.3%). Skin and soft tissue infections were the most common presentations, noted in 13 (50%) patients, followed by pulmonary infection presented in 10 (38.5%) patients. Fifteen patients (57.7%) had at least one underlying disease, and 11 (42.3%) were on immunosuppressive or long-term corticosteroid treatment. Susceptibility rates of linezolid, tigecycline, amikacin, trimethoprim-sulfamethoxazole, moxifloxacin, and imipenem were 100, 100, 96.4, 92.9, 82.1, and 42.9%, respectively. The 26 patients in this study were treated with various antibiotics. Mortality rate was 3.8%, and the patient who died had disseminated infection. Since epidemiology and antimicrobial susceptibility are evolving, continuous surveillance is mandatory in order to initiate appropriate treatment in a timely manner.
Genotypic and phenotypic insights into virulence factors of nosocomial Stenotrophomonas maltophilia isolates collected in Bulgaria (2011-2022).
Strateva T, Trifonova A, Stratev A … +1 more , Peykov S
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37405903 · Publisher ↗
The present study aimed to explore the virulence characteristics in 221 Bulgarian nosocomial Stenotrophomonas maltophilia isolates (2011-2022) via screening for the presence of virulence genes, their mutational variabili...
The present study aimed to explore the virulence characteristics in 221 Bulgarian nosocomial Stenotrophomonas maltophilia isolates (2011-2022) via screening for the presence of virulence genes, their mutational variability, and the corresponding enzyme activity. PCR amplification, enzymatic assays, whole-genome sequencing (WGS), and biofilm quantification on a polystyrene plate were performed. The incidence of virulence determinants was as follows: stmPr1 (encoding for the major extracellular protease StmPr1) 87.3%, stmPr2 (minor extracellular protease StmPr2) 99.1%, Smlt3773 locus (outer membrane esterase) 98.2%, plcN1 (non-hemolytic phospholipase C) 99.1%, and smf-1 (type-1 fimbriae, biofilm-related gene) 96.4%. The 1621-bp allele of stmPr1 was most frequently found (61.1%), followed by the combined allelic variant (17.6%), stmPr1-negative genotype (12.7%), and 868-bp allele (8.6%). Protease, esterase, and lecithinase activity was observed in 95%, 98.2%, and 17.2% of the isolates, respectively. The WGS-subjected isolates (n = 9) formed two groups. Five isolates possessed only the 1621-bp variant of stmPr1, higher biofilm formation ability (Optical Density at λ = 550 nm (OD550): 1.253-1.789), as well as a low number of mutations in the protease genes and smf-1. Three other isolates had only the 868-bp variant, weaker biofilm production (OD550: 0.788-1.108), and higher number of mutations within these genes. The only weak biofilm producer (OD550 = 0.177) had no stmPr1 alleles. In conclusion, the similar PCR detection rates did not allow differentiation of the isolates. In contrast, WGS permitted stmPr1 alleles-based differentiation. To the best of our knowledge, this is the first Bulgarian study presenting genotypic and phenotypic insights into virulence factors of S. maltophilia isolates.
Retraction note to: Treatment of methicillin resistant Staphylococcus aureus wound infection using vancomycin-loaded nanoparticles: An in vitro and in vivo study.
Alamir HTA, Taher MG, Mohammed MR … +2 more , Kareem SH, Jalil AT
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37368650 · Publisher ↗
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Prevalence and distribution of high-risk Human Papillomavirus in Western Türkiye between 2019 and 2022.
Ece GT, Pira D, Bodur GL
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37347660 · Publisher ↗
Human Papillomavirus (HPV) is a primarily sexually transmitted human pathogen linked with the formation of anogenital warts and several types of cancer including cervical cancer, oropharyngeal cancer, penile cancer, and...
Human Papillomavirus (HPV) is a primarily sexually transmitted human pathogen linked with the formation of anogenital warts and several types of cancer including cervical cancer, oropharyngeal cancer, penile cancer, and anal cancer. HPV genotypes are divided into high-risk and low-risk in accordance with their potential for carcinogenesis. The most notable high-risk genotypes are HPV-16 and HPV-18. In this study we report on the PCR analysis results of the cervical smear results of 328 females, and 50 males who have presented to a tertiary care university hospital in the port city of İzmir, Türkiye between August 2019 and August 2022. HPV-DNA positivity percentage was determined as 25.3% (96/378). 5 of 378 patients were HPV-18 positive (age range 31-80) whereas 27 patients were HPV-16 positive (age range 29-66). 64 patients were positive for other high-risk HPV types (age range 27-56). The positivity for HPV-16, HPV-18 and other high-risk HPV types were determined as 7.14%, 1.3% and 16.9% respectively. Our results demonstrate a 25.3% (96/378) positivity among tested patients moreover, out of 96 positive cases at least 32 are vaccine preventable. This study indicates the need for higher coverage of HPV vaccination in Western Türkiye.
Imipenem resistance associated with amino acid alterations of the OprD porin in Pseudomonas aeruginosa clinical isolates.
Nazari M, Ahmadi H, Hosseinzadeh S … +2 more , Sahebkar A, Khademi F
Acta Microbiol Immunol Hung · 2023 Sep · PMID 37342895 · Publisher ↗
Globally, the spread of carbapenem-resistant strains has limited treatment options for multidrug-resistant (MDR) Pseudomonas aeruginosa infections. This study aimed to determine the role of point mutations as well as the...
Globally, the spread of carbapenem-resistant strains has limited treatment options for multidrug-resistant (MDR) Pseudomonas aeruginosa infections. This study aimed to determine the role of point mutations as well as the expression level of the oprD gene in the emergence of imipenem-resistant P. aeruginosa strains isolated from patients referred to Ardabil hospitals. A total of 48 imipenem-resistant clinical isolates of P. aeruginosa collected between June 2019 and January 2022 were used in this study. Detection of the oprD gene and its amino acid alterations was performed using the polymerase chain reaction (PCR) and DNA sequencing techniques. The expression level of the oprD gene in imipenem-resistant strains was determined using the real-time quantitative reverse transcription PCR (RT-PCR) method. All imipenem-resistant P. aeruginosa strains were positive for the oprD gene based on the PCR results, and also five selected isolates indicated one or more amino acid alterations. Detected amino acid alterations in the OprD porin were Ala210Ile, Gln202Glu, Ala189Val, Ala186Pro, Leu170Phe, Leu127Val, Thr115Lys, and Ser103Thr. Based on the RT-PCR results, the oprD gene was downregulated in 79.1% of imipenem-resistant P. aeruginosa strains. However, 20.9% of strains showed overexpression of the oprD gene. Probably, resistance to imipenem in these strains is associated with the presence of carbapenemases, AmpC cephalosporinase, or efflux pumps. Owing to the high prevalence of imipenem-resistant P. aeruginosa strains due to various resistance mechanisms in Ardabil hospitals, the implementation of surveillance programs to reduce the spread of these resistant microorganisms along with rational selection and prescription of antibiotics is recommended.
Exploring the complex and multifaceted interplay of the gut microbiome and cancer prevention and therapy.
Kashyap S, Das A
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37307215 · Publisher ↗
Recent scientific research has indicated that the gut microbiota constitutes a nuanced, diverse ecosystem of microorganisms that have gained significant attention due to its crucial involvement in shaping human health an...
Recent scientific research has indicated that the gut microbiota constitutes a nuanced, diverse ecosystem of microorganisms that have gained significant attention due to its crucial involvement in shaping human health and diseases. In particular, the gut microbiota plays a pivotal role in cancer prevention, and disturbances in its composition and function, known as dysbiosis, that have been linked to an increased risk of developing various malignancies. The gut microbiota exerts a myriad of effects on the production of anti-cancer compounds, the host's immune system and inflammation, underscoring its crucial involvement in cancer. Additionally, recent studies have shown that the gut microbiota has a role in the development of cancer, influencing cancer risk, co-infections, disease progression, and treatment response. The observation of reduced efficacy of immunotherapy in patients receiving antibiotic treatment indicates a substantial influence of the microbiota in mediating the toxicity and response of cancer therapy, notably immunotherapy, and its immune-related side effects. A growing body of research has focused on cancer treatments that target the microbiome, including probiotics, dietary modifications, and faecal microbiota transplantation (FMT). The forthcoming era of personalised cancer therapies is anticipated to prioritise tumor evolution, molecular and phenotypic heterogeneity, and immunological profiling, with gut microbiota assuming a pivotal position in this domain. This review aims to offer clinicians a comprehensive perspective on the microbiota-cancer axis, including its influence on cancer prevention and therapy and highlights the importance of integrating microbiome science into the design and implementation of cancer therapies.
Pericarditis related to post-acute COVID infection: A case report and review of the literature.
Nguyen NN, Dudouet P, Dhiver C … +1 more , Gautret P
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37267081 · Publisher ↗
Cardiovascular involvement has been described in acute and recovered COVID-19 patients. Here, we present a case of symptomatic pericarditis with persistent symptoms for at least six months after the acute infection and r...
Cardiovascular involvement has been described in acute and recovered COVID-19 patients. Here, we present a case of symptomatic pericarditis with persistent symptoms for at least six months after the acute infection and report 66 published cases of pericarditis in discharged COVID patients. Patient mean age ± SD was 49.7 ± 13.3 years, ranging from 15 to 75 years and 57.6% were female. A proportion of 89.4% patients reported at least one comorbidity, with autoimmune and allergic disorders, hypertension and dyslipidaemia, as the most frequent. Only 8.3% of patients experienced severe symptoms of acute COVID-19. The time between acute COVID and pericarditis symptoms varied from 14 to 255 days. Chest pain (90.9%), tachycardia (60.0%) and dyspnoea (38.2%) were the most frequent symptoms in post-acute pericarditis. A proportion of 45.5% and 87% of patients had an abnormal electrocardiogram and abnormal transthoracic ultrasound, respectively. Colchicine combined with non-steroidal anti-inflammatory drug (NSAID) or acetylsalicylic acid (aspirin) were prescribed to 39/54 (72%) patients. Of them, 12 were switched to corticosteroid therapy due to non-response to the first-line treatment. Only 6 patients had persisting symptoms and were considered as non-respondent to therapy.Our report highlights that pericarditis should be suspected in COVID-19 patients with persistent chest pain and dyspnoea when pulmonary function is normal. Treatment with non-steroidal anti-inflammatory and colchicine is usually effective but corticosteroids are sometimes required.
Association of carbapenem and multidrug resistance with the expression of efflux pump-encoding genes in Pseudomonas aeruginosa clinical isolates.
Yousefi S, Nazari M, Ramazanzadeh R … +3 more , Sahebkar A, Safarzadeh E, Khademi F
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37227802 · Publisher ↗
Efflux pumps play an important role in the emergence of antibiotic-resistant Pseudomonas aeruginosa strains. The present study aimed to assess the expression of the MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY-OprM effl...
Efflux pumps play an important role in the emergence of antibiotic-resistant Pseudomonas aeruginosa strains. The present study aimed to assess the expression of the MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY-OprM efflux pumps in carbapenem-resistant and multidrug-resistant (MDR) P. aeruginosa strains isolated from clinical specimens between June 2019 and January 2022 in Ardabil city. The presence of efflux pump-encoding genes, i.e. mexA, mexC, mexE, and mexY, was assessed using the polymerase chain reaction (PCR) technique in 48 carbapenem-resistant and MDR P. aeruginosa strains. Real-time reverse transcription PCR was employed to evaluate the expression levels of mexA, mexC, mexE, and mexY genes. All 48 carbapenem-resistant and MDR P. aeruginosa strains harbored efflux pump-encoding genes including mexA, mexC, mexE, and mexY according to the PCR results. Overexpression of the MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY-OprM efflux pumps was detected in 75% (n = 36), 83.3% (n = 40), 10.4% (n = 5) and 41.6% (n = 20) of the clinical isolates of P. aeruginosa, respectively. This study revealed that the presence and overexpression of efflux pumps are associated with the emergence of carbapenem-resistant and MDR P. aeruginosa strains. Therefore, research on efflux pump inhibitors of P. aeruginosa will be a worthwhile endeavor to increase the clinical efficiency of available antibiotics and prevent ensuing treatment failure.
Frequency of mutations in erm(39) related to clarithromycin resistance and in rrl related to linezolid resistance in clinical isolates of Mycobacterium fortuitum in Iran.
Hashemzadeh M, Zadegan Dezfuli AA, Khosravi AD … +2 more , Ahmad Khosravi N, Hashemi Shahraki A
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37224008 · Publisher ↗
Mycobacterium fortuitum is a clinically important species among nontuberculous mycobacteria (NTM). Treatment of diseases caused by NTM is challenging. The aim of this study was identification of drug susceptibility and d...
Mycobacterium fortuitum is a clinically important species among nontuberculous mycobacteria (NTM). Treatment of diseases caused by NTM is challenging. The aim of this study was identification of drug susceptibility and detection of mutations in erm(39) related to clarithromycin resistance and in rrl related to linezolid resistance in clinical isolates of M. fortuitum in Iran. In the study, 328 clinical NTM isolates were subjected to identification based on rpoB and 15% of isolates were assigned to M. fortuitum. Minimum inhibitory concentration for clarithromycin and linezolid was determined by E-test. Altogether 64% of M. fortuitum isolates showed resistanc to clarithromycin and 18% of M. fortuitum isolates showed resistance to linezolid. PCR and DNA sequencing were performed in erm(39) and in rrl genes for detection of mutations related to clarithromycin and linezolid resistance, respectively. Sequencing analysis revealed (84.37%) single nucleotide polymorphisms in the erm(39). A total 55.55% of M. fortuitum isolates harbored an A→G, 14.81% harbored an C→A, 29.62% harbored an G→T mutation in erm(39) at position 124, 135, 275. Seven strains harbored point mutation in the rrl gene either at T2131C or at A2358G. Our findings showed M. fortuitum isolates have become a serious problem with high-level antibiotic resistance. The existence of drug resistance to clarithromycin and linezolid indicates more attention to the study of drug resistance in M. fortuitum.
Molecular epidemiology of carbapenem-resistant Enterobacteriaceae isolated from patients in COVID-19 wards and ICUs in a Bulgarian University Hospital.
Savova D, Niyazi D, Bozhkova M … +1 more , Stoeva T
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37204917 · Publisher ↗
Many studies report an increase in antimicrobial resistance of Gram - negative bacteria during the COVID-19 pandemic. Our aim was to evaluate the epidemiological relationship between carbapenem-resistant (CR) Enterobacte...
Many studies report an increase in antimicrobial resistance of Gram - negative bacteria during the COVID-19 pandemic. Our aim was to evaluate the epidemiological relationship between carbapenem-resistant (CR) Enterobacteriaceae isolates from patients in COVID-19 wards and to investigate the main mechanisms of carbapenem resistance in these isolates during the period April 2020-July 2021. A total of 45 isolates were studied: Klebsiella pneumoniae (n = 37), Klebsiella oxytoca (n = 2), Enterobacter cloacae complex (n = 4) and Escherichia coli (n = 2). Multiplex PCR was used for detection of genes encoding carbapenemases from different classes (blaKPC, blaIMP, blaVIM, blaNDM, blaOXA-48). For epidemiological typing and analysis, ERIC PCR was performed. Two clinical isolates of E. cloacae, previously identified as representatives of two dominant hospital clones from the period 2014-2017, were included in the study for comparison. In the CR K. pneumoniae group, 23 (62.2%) carried blaKPC, 13 (35.1%) blaNDM, 10 (27.0%) blaVIM, and 9 (24.3%) were positive for both blaKPC and blaVIM. The blaKPC was identified also in the two isolates of K. oxytoca and blaVIM in all E. cloacae complex isolates. The two CR isolates of E. coli possessed blaKPC and blaOXA-48 genes. Epidemiological typing identified 18 ERIC profiles among K. pneumoniae, some presented as clusters of identical and/or closely related isolates. The carbapenem resistance in the studied collection of isolates is mediated mainly by blaKPC. During the COVID-19 pandemic intrahospital dissemination of CR K. pneumoniae, producing carbapenemases of different molecular classes, as well as continuing circulation of dominant hospital clones of multidrug-resistant E. cloacae complex was documented.
High seroprevalence of hepatitis E virus (HEV) in South Transdanubia, Hungary (2010-2022).
Balázs B, Boros Á, Pankovics P … +1 more , Reuter G
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37159338 · Publisher ↗
Hepatitis E virus (HEV) is an increasingly recognized etiological agent of acute, chronic and extrahepatic human infections with primarily zoonotic origin in Europe. Limited numbers of comprehensive population-based stud...
Hepatitis E virus (HEV) is an increasingly recognized etiological agent of acute, chronic and extrahepatic human infections with primarily zoonotic origin in Europe. Limited numbers of comprehensive population-based studies are available related to HEV seroepidemiology, especially from Central Europe.The aim of this study was to investigate the seroprevalence and trends of total and IgM antibodies against HEV in different age groups in the population of South Transdanubia, Hungary, within a thirteen years long period between the years 2010 and 2022.We retrospectively analysed the serological test results of HEV total and HEV IgM antibodies carried out by ELISA technique using Dia.Pro (Diagnostic Bioprobes, Italy) kit from serum samples collected from patients with or without hepatitis between January 1, 2010 and December 31, 2022.The number of tested samples (∑6,996 for total antibody and ∑6,582 for IgM) increased during the study period. The average HEV total and the IgM antibody seropositivities were 33% (2,307/6,996 samples) and 9.6% (642/6,582 samples), respectively, in the study population. The HEV total antibody seropositivity varied in different age groups between 3.9% (age group 1-5 years) and 58.6% (86-90 years) and showed an increasing positivity by age. At the age groups >50 years, nearly half (43%) of the population had antibodies against HEV. The HEV IgM positivity had an increasing trend of up to 13.9% in the age group 81-85 years.High HEV total and IgM antibody seroprevalence were detected in South Transdanubia, Hungary, confirming that this region is highly endemic for HEV infections in Europe.
Investigation of in vitro efficacy of meropenem/polymyxin B and meropenem/fosfomycin combinations against carbapenem resistant Klebsiella pneumoniae strains.
Adaleti R, Nakipoğlu Y, Çalık Ş … +4 more , Arıcı N, Kansak N, Şenbayrak S, Aksaray S
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37133999 · Publisher ↗
The incidence of infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) is increasing worldwide, and very limited number of effective antibiotics are available for therapy. In our study, the in vitro effi...
The incidence of infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) is increasing worldwide, and very limited number of effective antibiotics are available for therapy. In our study, the in vitro efficacy of meropenem/polymyxin B and meropenem/fosfomycin combinations against CRKP strains was investigated. The efficiency of meropenem/polymyxin B and meropenem/fosfomycin combinations was tested by checkerboard microdilution and checkerboard agar dilution methods, respectively, against 21 CRKP strains containing major carbapenem resistant genes (7 blaKPC, 7 blaOXA-48 gene, and 7 blaOXA-48+ blaNDM), and seven additional CRKP strains without carbapenemase genes.Among the 28 CRKP strains, the meropenem/polymyxin B combination was synergistic in ten (35.7%), partially synergistic in 12 (42.8%), and indifferent in six (21.4%) isolates. The meropenem/fosfomycin combination was found to be synergistic in three isolates (10.7%), partially synergistic in 20 (71.4%), and indifferent in five (17.8%). In 21 strains containing carbapenem resistance genes, meropenem/polymyxin B and meropenem/fosfomycin combinations exhibited synergistic/partial synergistic effects in 15 (71.4%) and 16 (76.2%) strains, respectively, compared to 100% synergistic/partial synergistic efficiency in both combinations in seven strains free of carbapenemase genes. No antagonistic effect was detected in either combination.Regardless of presence or absence of carbapenem resistance genes, meropenem/polymyxin B and meropenem/fosfomycin combinations both demonstrated high synergistic and partial synergistic activity against 78.4% and 82.1% of CRKP strains, respectively. Also, they have no antagonistic effects and can be used successfully to prevent therapeutic failure with monotherapy, according to our in vitro studies.
West Nile virus infections in Hungary: Epidemiological update and phylogenetic analysis of the Hungarian virus strains between 2015 and 2022.
Nagy A, Horváth A, Mezei E … +6 more , Henczkó J, Magyar N, Nagy O, Koroknai A, Csonka N, Takács M
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37130018 · Publisher ↗
Following the introduction of the West Nile virus (WNV) into Hungary in 2004, it has shortly become one of the most important human arbovirus infections, with a gradually increasing number of cases. The study aimed to su...
Following the introduction of the West Nile virus (WNV) into Hungary in 2004, it has shortly become one of the most important human arbovirus infections, with a gradually increasing number of cases. The study aimed to summarize the current epidemiological situation in Hungary and sequence the WNV PCR-positive clinical specimens and virus isolates by next-generation whole genome sequencing (NGS) to obtain a detailed phylogenetic analysis of the circulating virus strains. Whole blood and urine samples from confirmed WNV-infected patients and WNV isolates were investigated by reverse transcription PCR assays. Genome sequencing was carried out by Sanger-method, followed by NGS on the Illumina MiSeq platform. Altogether 499 human infections were diagnosed between 2004 and 2022. A particularly remarkable increase in human WNV infections was observed in 2018, while the number of reported cases significantly decreased during the COVID-19 pandemic. Between 2015 and 2022, 15 WNV isolates, and 10 PCR-positive clinical specimens were investigated by NGS. Phylogenetic analysis revealed that the major European WNV lineage 2 clades, namely the Eastern European (or Russian) and the Central European (or Hungarian) clades, are presented in Hungary. Strains of the Balkan and other European clusters within the Central European clade are co-circulating in the country, following a characteristic geographical distribution. In Hungary, the presence and co-circulation of multiple lineage 2 WNV strains could be identified in the last few years. Therefore, in light of the 2018 WNV outbreak, sequence-based typing of the currently circulating strains could highly support outbreak investigations.
Prevalence of carbapenemases in Enterobacterales from urine specimens in an university hospital in Istanbul, Turkey.
Güler MS, Aygün G, Akkuş S … +3 more , Kuşkucu AM, Küçükbasmacİ Ö, Gönüllü N
Acta Microbiol Immunol Hung · 2023 Jun · PMID 37060554 · Publisher ↗
We aimed to investigate the prevalence of carbapenemases in Enterobacterales strains isolated from urine specimens between July 2019 and July 2020.CIM and modified CIM tests were applied as well as detection of blaOXA-48...
We aimed to investigate the prevalence of carbapenemases in Enterobacterales strains isolated from urine specimens between July 2019 and July 2020.CIM and modified CIM tests were applied as well as detection of blaOXA-48, blaNDM, blaVIM, blaKPC and blaIMP genes was performed by multiplex PCR.One hundred fifty of 3,242 Enterobacterales strains were found to be carbapenem resistant and 46 were included in the study. Forty five (98%) of the 46 strains included in the study were Klebsiella spp. and one (2%) of them was Escherichia coli. Susceptibility to ceftazidime-avibactam, amikacin and gentamicin was 97%, 11% and 9%, respectively. Forty three (94%) isolates were found positive at 2 and 4 h with CIM test. Forty four (97%) strains were found positive at 4 h and 43 (94%) strains were found positive at 2 h with modified CIM test.While blaOXA-48, blaNDM and blaOXA-48 with blaNDM association were found in Klebsiella spp. isolates in 55%, 27% and 11%, respectively, blaVIM, blaKPC, blaIMP were not found. Only blaOXA-48 and blaNDM-1 were detected in the E. coli strain.None of the investigated genes were detected in three Klebsiella strains but with whole genome analysis the combination of blaOXA-534, blaCMY-99 and blaKPC-3 was found in the first strain, blaOXA-370 in the second strain and no resistance gene was found in the third strain.Ceftazidime-avibactam was found to be active against 97% of strains, and the most common resistance genes were blaOXA-48 and blaNDM-1. Previously undetected resistance genes have been identified in our country.
Prevalence and genetic characteristics of fusidic acid resistant Staphylococcus aureus clinical isolates: Emergence of t030 strains carrying fusB in Tehran, Iran.
Goudarzi M, Seyedjavadi S, Bagheri P … +2 more , Dadashi M, Nasiri MJ
Acta Microbiol Immunol Hung · 2023 Jun · PMID 36961740 · Publisher ↗
The literature on fusidic acid resistant Staphylococcus aureus strains is scarce in Iran, although the emergence of these strains in health care settings is increasing. This descriptive cross-sectional study was conducte...
The literature on fusidic acid resistant Staphylococcus aureus strains is scarce in Iran, although the emergence of these strains in health care settings is increasing. This descriptive cross-sectional study was conducted on 68 fusidic acid resistant S. aureus strains to learn about the molecular characteristics and antimicrobial resistance of strains isolated from hospitalized patients. In the present study, the prevalence of resistance to fusidic acid in S. aureus isolates was 15.1%. Fusidic acid resistance determinative factors (fusB, fusC and fusD) were identified by multiplex PCR assay. To detect the existence of fusA and fusE determinants and their mutation status, amplifications and sequencing were performed. Molecular characterization of fusidic acid resistant isolates was investigated by SCCmec and spa typing methods. All strains were MRSA and multi drug resistant. Two (2.9%) and 31 (45.6%) isolates were resistant to vancomycin and mupirocin respectively. The SCCmec type IV was highly prevalent representing 50% followed by types III (51.5%), and SCCmec types II (13.2%). fusB, was the most predominant acquired gene (66.2%) followed by fusC (19.1%), and fusA (14.7%). The mutations in fusA were present in 10 isolates with 5 (50%) having L461K mutation showing fusidic acid MIC values of ≥256 μg ml-1 followed by H457Y (40%), and H457Q (10%) showing fusidic acid MIC values of 128 and 64 μg ml-1 respectively. Isolates were allocated to ten particular t030 (22.1%), t037 (14.6%), t408 (11.8%), t064 (11.8%), t008 (10.3%), t002 (8.8%), t005 (5.9%), t790 (5.9%), t318 (4.4%), and t018 (4.4%) spa types. fusA positive isolates were assigned to particular spa types t002 (60%), and t005 (40%). There may be be a spreading of fusidic acid resistance among MRSA, creating worrying public concern. This research notes the importance of adequate data of local prevalence of FA-resistant MRSA in Iran for taking appropriate measures to treat, control and reduce the incidence of these isolates.
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