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Acta Microbiologica Et Immunologica Hungarica[JOURNAL]

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Molecular characterization and antibiotic resistance of Staphylococcus aureus isolated from clinical specimens in an urban university hospital in Bangkok, Thailand.

Boonsilp S, Sikora J, Rupprom K … +5 more , Acılıoğlu S, Homkaew A, Nutalai D, Phumisantiphong U, Wongsuk T

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36787135 · Publisher ↗

Little is known about the properties of the current strains of Staphylococcus aureus associated with human infections in Thailand. This study examined the rate of resistance to various antimicrobial agents, prevalence of... Little is known about the properties of the current strains of Staphylococcus aureus associated with human infections in Thailand. This study examined the rate of resistance to various antimicrobial agents, prevalence of virulence genes, and biofilm formation ability of 60 clinical S. aureus isolates from a single Thai hospital. Moreover, the Staphylococcus protein A gene (spa) type was determined among methicillin-resistant S. aureus (MRSA) isolates. Most methicillin-susceptible S. aureus isolates were susceptible to antimicrobials, whereas all MRSA isolates were resistant to erythromycin and clindamycin. The major virulence genes among the isolates were hla (100%), sec (26.7%), and hlb (20%). Meanwhile, 46.7% and 1.7% of the strains exhibited low-grade and high-grade biofilm formation, respectively. Our findings revealed the presence of spa types among MRSA isolates were: t032 (37.5%, 6/16), t088 (25%, 4/16), t001 (12.5%, 2/16), t008 (6.25%, 1/16), t034 (6.25%, 1/16), t439 (6.25%, 1/16), and t1928 (6.25%, 1/16). These findings will be useful for future research on anti-virulence therapies and the epidemiology of the strains circulating in our hospital.

Establishing a molecular laboratory in COVID-19 pandemic: The experience of a regional laboratory in Spain.

Moure Z, Cuadros E, Pablo-Marcos D … +3 more , Reina MJ, de Benito I, Campo AB

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36753298 · Publisher ↗

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 diagn... 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.

Staphylococcal biofilm on wedding rings worn by laboratory workers.

Ćirković I, Pejović A, Jovićević M … +3 more , Brkić S, Djukić S, Božić DD

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36735239 · Publisher ↗

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 s... 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.

Prevalence and clonal diversity of methicillin-resistant Staphylococcus aureus and methicillin-resistant Staphylococcus pseudintermedius isolated from dogs and cats with eye discharge.

Cengiz S, Okur S, Oz C … +7 more , Turgut F, Gumurcinler B, Sevuk NS, Kekec AI, Cepoglu H, Sevimli U, Adiguzel MC

Acta Microbiol Immunol Hung · 2023 Jun · PMID 36723933 · Publisher ↗

OBJECTIVES: Methicillin-resistant Staphylococcus (MRS) has originated, spread extensively, and become a prominent source of bacterial infections in both human and animal. METHODS: We report the prevalence, genetic divers... OBJECTIVES: Methicillin-resistant Staphylococcus (MRS) has originated, spread extensively, and become a prominent source of bacterial infections in both human and animal. METHODS: We report the prevalence, genetic diversity, and antimicrobial resistance pattern of Staphylococcus pseudintermedius and Staphylococcus aureus strains isolated from dogs and cats with eye discharges. RESULTS: A total of 12 (6.0%) coagulase-positives staphylococci were identified as (6/200, 3%) S. aureus and (6/200, 3%) S. pseudintermedius. The phenotypic methicillin resistance of S. aureus and S. pseudintermedius were 50.0% (3/6) and 16.7% (1/6), respectively. None of the isolates showed biofilm formation in the microtiter plate assay. The highest resistance (50.0%) for S. pseudintermedius strains was detected against clindamycin and tetracycline. 67.0% of S. aureus isolates were resistant to penicillin-G. The PCR analysis conducted for detection of mecA gene indicated that only one S. aureus isolated from a cat was mecA gene positive. Phylogenetic analysis based on repetitive sequence-based PCR (rep-PCR) showed that all strains were typable and generated PCR products ranging from 800 bp to 4,400 bp. The lineages ST241 and the novel ST2361 in multi-locus sequence typing (MLST) analysis were detected in one methicillin-susceptible S. pseudintermedius and methicillin-resistant S. pseudintermedius of dogs, respectively. In addition, the lineages ST4155 and ST7217 of two methicillin-resistant S. aureus strains of cats were connected epidemiologically to previously reported cases. CONCLUSIONS: These results indicate epidemiologically related strains (ST241, ST4155, and ST7217) transferring between animals and humans. Therefore, the strategies to combat the widespread MRS should be based on collaboration between human and veterinary medicine under the One Health concept.

Characteristics of multiresistant Pseudomonas aeruginosa isolates from burn patients in Iran.

Abednezhad A, Bakhshi B, Moghadam NA … +3 more , Faraji N, Derakhshan-Nezhad E, Mohammadi Barzelighi H

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36689252 · Publisher ↗

Infections caused by multidrug resistant (MDR) Pseudomonas aeruginosa isolates in burn patients restrict therapeutic strategies. The current study aimed to analyze antibiotic resistance genes and multilocus sequence typi... Infections caused by multidrug resistant (MDR) Pseudomonas aeruginosa isolates in burn patients restrict therapeutic strategies. The current study aimed to analyze antibiotic resistance genes and multilocus sequence typing (MLST) of P. aeruginosa strains isolated from burn patients in Shahid Motahari hospital in Tehran, Iran.Altogether 63 P. aeruginosa isolates were characterized in this study. Antibiotic susceptibility testing was performed by disc diffusion method. PCR was performed to determine the frequency of resistance genes. The expression rates of mexB, mexY genes were evaluated by Real-Time PCR. Genotyping of isolates was performed by MLST analysis. All isolates were MDR in this study. The highest resistance was detected against gentamicin, tobramycin, and cefoxitin (100%), while all isolates were susceptible to colistin. Altogether 14 resistance profiles were determined, and profile 1 included more than 50% of the isolates with the highest resistance. In this study blaampC, blaVIM-2, blaOXA-10, and aac(6')-Ib resistance genes were detected in all isolates. The expression levels of mexB and mexY genes were upregulated in 66.6 and 88.8% of MDR isolates, respectively. Overexpression of both genes was detected in 55.5% of the isolates.MLST analysis revealed five sequence types (STs), including ST235, ST664, ST532, ST2637, and ST230, which showed a significant relationship with antibiotic resistance profiles. The present study indicates an increase in antibiotic resistance against different antibiotic families among P. aeruginosa isolates. We describe the circulation of globally distributed STs among hospitalized patients, and we report ST235 as the most common MDR clone in our study.

Investigation of NDM-1 and OXA-48 producing carbapenem resistant Klebsiella pneumoniae ST15 in Iran.

Mohajer HB, Salimizand H, Gharanizadeh D … +2 more , Hossainpanahi A, Ramazanzadeh R

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36648758 · Publisher ↗

The aim of this study was to determine the frequency of carbapenem resistant Klebsiella pneumoniae (CRKP) sequence types (STs) in Iran. Samples were collected from three university hospitals in Sanandaj, Iran, from Decem... The aim of this study was to determine the frequency of carbapenem resistant Klebsiella pneumoniae (CRKP) sequence types (STs) in Iran. Samples were collected from three university hospitals in Sanandaj, Iran, from December 2016 to March 2018. Antibiotic susceptibility testing, phenotypic and genotypic detection of carbapenemases were performed. Common K. pneumoniae capsular types were sought for all isolates. The genetic relatedness of isolates was investigated by multilocus sequence typing (MLST). Plasmids were detected by PCR-based Replicon Typing (PBRT). During the study, 67 K. pneumoniae isolates were identified. Of which, 18 (26.9%) isolates were detected as carbapenem-resistant. The most effective antibacterial agent was tigecycline (97%, 65 isolates) followed by imipenem and ertapenem (73.13%, 49 isolates). PCR showed that 13 isolates (19.4%) had blaNDM-1 gene and 5 (7.5%) harbored blaOXA-48. Examination of common capsular types showed that 2 isolates had K2 and 2 others had K54. REP-PCR revealed 10 clones and 11 singleton strains. MLST analysis of CRKP found ST15 as the most common type (13 isolates, 72.2%), but other STs were also detected namely, ST19, ST117, ST1390, and ST1594. ColE1 and IncL/M plasmids were the carriers of blaNDM-1 and blaOXA-48, respectively. The results showed that CRKP spread in our health centers. Our results, therefore, indicate a worrying trend of resistance to carbapenems in K. pneumoniae.

Geographic distribution of antibiotic resistance of Helicobacter pylori: A study in Bulgaria.

Boyanova L, Gergova G, Kandilarov N … +4 more , Boyanova L, Yordanov D, Gergova R, Markovska R

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36640264 · Publisher ↗

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 inc... 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.

Detection of multidrug-resistant Acinetobacter baumannii from burn patients and healthcare workers in Iran.

Firoozeh F, Bakhshi F, Dadashi M … +3 more , Badmasti F, Zibaei M, Omidinia N

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36640263 · Publisher ↗

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 a... 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.

Analysis of biofilm formation in nosocomial Stenotrophomonas maltophilia isolates collected in Bulgaria: An 11-year study (2011-2022).

Strateva T, Trifonova A, Sirakov I … +5 more , Borisova D, Stancheva M, Keuleyan E, Setchanova L, Peykov S

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36640262 · Publisher ↗

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 t... 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.

Comparison of performance of LIAISON SARS-CoV-2 antigen assay with RT-PCR during the Omicron wave.

Arici N, Kansak N, Şentürk T … +2 more , Baydili K, Aksaray S

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36622645 · Publisher ↗

Due to the newly emerging Omicron variant, there is a need to re-evaluate the performance of automated antigen tests. Our study aim was to evaluate the performance of the automated Liaison SARS-CoV-2 antigen assay agains... Due to the newly emerging Omicron variant, there is a need to re-evaluate the performance of automated antigen tests. Our study aim was to evaluate the performance of the automated Liaison SARS-CoV-2 antigen assay against reverse transcriptase polymerase chain reaction (RT-PCR) in samples with Omicron variant.A prospective study was performed on 373 combined oro-nasopharyngeal samples (NPS) randomly collected from symptomatic patients. NPS were tested with Liaison SARS-CoV-2 Ag test (DiaSorin, Italy) and DS Coronex COVID-19 Multiplex RT-PCR Diagnosis Kit (DS BioTechnology, Ankara, Turkey).Of 373 samples, 124 (33.2%) were found to be RT-PCR positive and 249 (66.8%) RT-PCR negative. Taking RT-PCR as a reference, the sensitivity and specificity of the Liaison SARS-CoV-2 Ag assay were found as 84.6% (95%CI 77.3%-90%) and 100% (95%CI 98.5%-100%), respectively. For samples with a cycle threshold (Ct) value <25 (high viral load), the sensitivity increased to 100%. When antigen concentration and Ct values were compared, a strong negative correlation between antigen and Ct values was determined (P < 0.001).The Liaison antigen test met the performance criteria recommended by the WHO for samples with the Omicron variant. In addition, it showed excellent sensitivity and specificity in patients with high viral load. Therefore, Liaison antigen test can be a reliable and useful alternative in the diagnosis of SARS-CoV-2 infection, particularly in resource-constrained laboratories.

Dissemination of epidemic ST239/ST241-t037-agrI-SCCmecIII methicillin-resistant Staphylococcus aureus in a Tunisian trauma burn intensive care unit.

Raddaoui A, Chebbi Y, Bouchami O … +4 more , Frigui S, Messadi AA, Achour W, Thabet L

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36525058 · Publisher ↗

Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen causing health care-infections in the world, especially in burns. The aim of this study was to assess the extent of dissemination of MRSA isolat... Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen causing health care-infections in the world, especially in burns. The aim of this study was to assess the extent of dissemination of MRSA isolated from burn patients in Burn Intensive Care Unit in Tunisia and to evaluate the frequency of virulence and antibiotics resistance genes. Among the 72 S. aureus isolates analyzed in the study, 54% were MRSA. The majority of MRSA (94.8%) were multidrug resistant and they had a high resistance rates to kanamycin (94.8%), tobramycin (90%), tetracycline (94.8%) and ciprofloxacin and rifampicin (87%, each). The gene aac(6')-Ie-aph(2″)-Ia conferring resistance to kanamycine and tobtamycin were detected in all isolates and the aph(3')-Ia gene conferring resistance to gentamicin were detected in 2.8% of resistant isolates. Tetracycline resistance genes tet(M), tet(K) and tet(L) were detected in 100%, 10.8% and 2.8% of the isolates, respectively. The SCCmec type III and the agr type I were the most predominant (69.2% and 90%, respectively). The 27 SCCmecIII-agrI isolates were clustered into two PFGE types A and B. The two representative isolates of PFGE clusters A and B belonged to ST239-t037 and ST241-t037 respectively. As conclusion, our results showed a high prevalence of MRSA in trauma burn intensive care unit belonging to two multidrug resistant clones ST239/ST241-agrI-t037-SCCmecIII MRSA. We also demonstrated that MRSA was disseminated between burn patients.

Distribution of virulence determinants among Escherichia coli ST131 and its H30/H30-Rx subclones in Turkey.

Er DK, Dündar D, Uzuner H

Acta Microbiol Immunol Hung · 2023 Mar · PMID 36459132 · Publisher ↗

Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading pathogen in urinary tract infection. In recent years multidrug-resistant B2-ST131 E. coli clonal group has disseminated worldwide. The ST131 and its subc... Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading pathogen in urinary tract infection. In recent years multidrug-resistant B2-ST131 E. coli clonal group has disseminated worldwide. The ST131 and its subclones H30 and H30-Rx have been identified only in a few studies from Turkey. The aim of this study is to investigate the presence of ST131 and its subclones and to analyze their adhesin virulence genes and antimicrobial resistance. A total of 250 urinary ExPEC isolates were included in the study. Resistance rates of 16 antimicrobial agents were determined by disk-diffusion. Multidrug-resistance and ESBL production were analyzed. Altogether 8 adhesin genes were investigated namely, papAH, fimH, sfa/focDE, focG, afa/draBC, iha, bmaE and gafD. A total of 39 ST131 isolate were determined and 33 (84.6%) were multidrug-resistant. ESBL production was detected in 34 (87.2%) ST131 and 61 (28.9%) of non-ST131 strains. In our study, we found a strong correlation between ST131 strains and fimH, iha, afa/draBC, papAH virulence determinants. Twenty-nine (85.3%) of 34 ST131-O25b-H30 isolates were identified as H30-Rx. All the papAH gene positive isolates were identified within ST131-O25b-H30-Rx lineage. Non-H30-Rx isolates within H30 isolates were identified as pattern 2. Almost 16% of the isolates were identified as ST131 regardless of clinical syndrome and approximately 34% of the multidrug-resistant isolates were H30-Rx subclone. We report H30-Rx as the dominant subclone of ST131 in our study. Imipenem, fosfomycin and nitrofurantoin proved to be the most effective agents according to antibiotic resistance patterns of both ST131 and non-ST131 E. coli strains.

Cluster of cases due to Shigella flexneri producing CTX-M-15 in Spain.

Kocsis E, Díaz de Tuesta JL, Sánchez J … +4 more , Santamaría R, Moragas M, Herrera-León S, Cisterna R

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36454544 · Publisher ↗

The aim of our study was to delineate an outbreak of gastroenteritis caused by Shigella flexneri and affecting sixteen persons between May and June 2014 in Bilbao, Spain. All patients exhibited symptoms after consuming k... The aim of our study was to delineate an outbreak of gastroenteritis caused by Shigella flexneri and affecting sixteen persons between May and June 2014 in Bilbao, Spain. All patients exhibited symptoms after consuming kebab in the same kebab shop.The outbreak is described through the clinical cases, the microbiological and molecular genetic diagnosis, and the epidemiologic investigation. Minimum inhibitory concentrations for ampicillin, amoxicillin plus clavulanic acid, third and fourth generation cephalosporins, carbapenems, monobactams, aminoglycosides, fluoroquinolones, co-trimoxazole, colistin and tigecycline were measured. The S. flexneri strains were screened by PCR for TEM, SHV, CTX-M beta-lactamases and plasmidic AmpCs and aac(6')-Ib gene. Serotyping, pulsed field gel-electrophoresis, conjugation assay, plasmid sizing by S1 enzyme digestion and Southern blot hybridization were accomplished.All the S. flexneri isolates proved to be serotype 2 and produced extended-spectrum beta-lactamase (ESBL). Carbapenems, fluoroquinolones, tigecycline, colistin, and co-trimoxazole remained active antibiotics. All the strains harboured blaCTX-M-15 and blaOXA-1 genes. The strains hosted two high-molecular weight plasmids of 100 and 230 kb, respectively. According to the hybridization assay blaCTX-M-15 was located on the plasmid of 230 kb. The identical pulsotype verified the presence of outbreak.Remarkable, that one of the food handlers has travelled recently to Pakistan, where ESBL-producing Shigella strains had been reported previously. To the best of our knowledge, this is the first outbreak caused by CTX-M-15-expressing S. flexneri in Spain and as well as in Europe.

Multiple detection of hypermucoviscous and hypervirulent strains of Klebsiella pneumoniae: An emergent health care threat.

Ventura A, Addis E, Bertoncelli A … +1 more , Mazzariol A

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36427200 · Publisher ↗

This study focused on the characterization of 19 hypermucoviscous Klebsiella pneumoniae strains, that were identified from 26 hypermucosal strains. In order to identify hypermucoviscous strains of K. pneumoniae, the stri... This study focused on the characterization of 19 hypermucoviscous Klebsiella pneumoniae strains, that were identified from 26 hypermucosal strains. In order to identify hypermucoviscous strains of K. pneumoniae, the string test was applied. This phenotype is known in the literature as one of the virulence factors of this species together with the production of biofilm and other hypervirulence factor genes such as: rmpA, rmpA2, iucA, iroB, peg-344. We also investigated presence of magA gene that correlates with the hyper-production of capsule of K1 serotype. Of the strains under study, 13 out of 19 harboured at least one virulence factor.Sequence type (ST) was determined in order to identify known high-risk clones or new emerging high-risk clones and their variability in a single clinical setting. Important STs found among these strains were ST65 and ST29. Carbapenem resistance was also investigated and 4 out of 19 strains harboured at least a carbapenemase: one strain harboured a KPC enzyme alone, one strain carried a KPC and an OXA-48 like, one strain produced OXA-48-like alone, and the last strain harboured two metallo-β-lactamases (VIM-1 and NDM-5) plus OXA-48-like. In particular, this latter strain belongs to ST383, which was recently reported in Northern Italy as a hypervirulent and XDR strain.The global spread of hypervirulent K. pneumoniae is an important epidemiological issue that should be considered in diagnostic and therapeutic managements of patients with K. pneumoniae infections.

Antimicrobial resistance patterns and virulence gene profiles of Salmonella enteritidis and Salmonella typhimurium recovered from patients with gastroenteritis in three cities of Iran.

Sharahi JY, Hashemi A, Javad Mousavi SM … +2 more , Pournajaf A, Bidhendi SM

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36370370 · Publisher ↗

This study evaluated distribution of virulence factors and antibiotic resistance in clinical isolates of Salmonella enteritidis and Salmonella typhimurium in three cities of Iran. Altogether 48 S. enteritidis and S. typh... This study evaluated distribution of virulence factors and antibiotic resistance in clinical isolates of Salmonella enteritidis and Salmonella typhimurium in three cities of Iran. Altogether 48 S. enteritidis and S. typhimurium isolates were collected from patients at certain Iranian hospitals between May 2018 and September 2021. Antimicrobial susceptibility testing was performed by disk diffusion and broth microdilution methods. The presence of antibiotic-resistance genes (blaTEM,blaSHV,blaCTX-M,blaNDM,strA, strB, aadA1, tetA, tetB, floR, sul1, sul2, dfrA), integrons (classe 1 and 2), and virulence-associated genes (invA, stn, sopB, spvC, rck, phoPQ) was investigated by PCR and sequencing. Antimicrobial agents like trimethoprim-sulfamethoxazole and imipenem represent highly efficient agents with 97% susceptibility. S. enteritidis and S. typhimurium exhibited high resistance to ciprofloxacin (n = 20, 71.43%) and ceftazidime (n = 9, 45%), respectively. Overall, 3 (6.25%), 13 (27.08%), and 6 (12.5%) isolates were divided into strong, moderate, and weak biofilm producers, respectively. Moreover, blaCTX-M,blaTEM, blaSHV, sul1, sul2, tetA, tetB, floR, strA, and strB resistant genes were detected in 10 (20.8%), 5 (10.4%), 1 (2.08%), 7 (14.58%), 1 (2.08%), 3 (6.25%), 2 (4.1%), 1 (2.08%), 2 (4.1%), 2 (4.1%), respectively. Furthermore, 7 (14.58%) strains had classe 1 integron. All tested S. enteritidis strains had invA and sopB, and all S. typhimurium strains had invA and phoPQ. However, spvC remained undetected in all isolates. Extensive surveillance and efficient control measures against infection help to stop the upsurge of various antibiotic-resistant isolates.

Genome analysis of clinical isolate of Campylobacter fetus subspecies fetus MMM01 from India reveals genetic determinants of pathogenesis and adaptation.

Pinto DS, Prithvisagar KS, Rohit A … +3 more , Karunasagar I, Karunasagar I, Kumar BK

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36370369 · Publisher ↗

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 adapt... 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.

Distribution of emm, superantigen and other virulence genotypes and detection of phylogenetic relationships in group A streptococcal isolates.

Kızılyıldırım S, Köksal F, Güneri CÖ

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36370368 · Publisher ↗

Group A streptococci are important pathogens with various virulence factors, such as M protein, superantigens, hemolysins, deoxyribonuclease, and proteases. The aims of this study are to investigate the detection of emm... Group A streptococci are important pathogens with various virulence factors, such as M protein, superantigens, hemolysins, deoxyribonuclease, and proteases. The aims of this study are to investigate the detection of emm genotypes and other virulence genes, such as SAgs, DNase, protease, antibiotic resistance, and phylogenetic relationships in GAS strains isolated from clinical samples.Test strains were obtained from Çukurova University Balcalı Hospital and regional hospitals in Adana province. The M proteins were detected by sequence analysis of emm genes. SAgs and other virulence gene profiles were determined using the Multiplex-PCR method. The antibiotic susceptibility of the isolates was performed by the disc diffusion method and evaluated according to CLSI criteria. The PFGE method was used to determine the clonal relationship between the strains.The emm gene was positive in 86 isolates. The most common emm genotypes were emm28 (22%), emm1 (18.6%), emm12 (13.9%), and emm3 (11.6%). Also, the most common virulence genes were speG (58.1%), speC (56.9%), sdaB (53.4%), and mac (53.4%). The rates of resistance to erythromycin, clindamycin, levofloxacin, ciprofloxacin and telithromycin were 19.8%, 16.3%, 4.7%, 3.5%, and 3.5%, respectively.As a result, additional regional studies on the detection and prevalence of GAS virulence factors in Turkey are required. We believe that this study will provide valuable information for epidemiological studies on emm sequences, Sags, and other virulence factors of Streptococcus pyogenes in Turkey.

COVID-19 in elderly: Correlations of viral load, clinical course, laboratory parameters, among patients vaccinated with CoronaVac.

Altintop SE, Unalan-Altintop T, Cihangiroglu M … +5 more , Onarer P, Milletli-Sezgin F, Gozukara M, Gozukara B, Zengin E

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36370367 · Publisher ↗

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 hypox... 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.

Respiratory pathogens among ill pilgrims and the potential benefit of using point-of-care rapid molecular diagnostic tools during the Hajj.

Hoang VT, Dao TL, Ly TDA … +5 more , Drali T, Yezli S, Parola P, Pommier de Santi V, Gautret P

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36370366 · Publisher ↗

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 usin... 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.

Ginsenoside Rg1 modulates intestinal microbiota and supports re-generation of immune cells in dexamethasone-treated mice.

Yousuf S, Liu H, Yingshu Z … +5 more , Zahid D, Ghayas H, Li M, Ding Y, Li W

Acta Microbiol Immunol Hung · 2022 Dec · PMID 36342667 · Publisher ↗

Ginsenoside Rg1 is one of the major ginsenosides found in roots of Panax ginseng and Panax notoginseng. Ginsenoside Rg1 is known to possess various biological activities including immunity enhancement activity. However,... Ginsenoside Rg1 is one of the major ginsenosides found in roots of Panax ginseng and Panax notoginseng. Ginsenoside Rg1 is known to possess various biological activities including immunity enhancement activity. However, it is not clear whether the regulation of immune function by Rg1 is related to the intestinal microbiota. In the present study, the immuno-modulatory and gut microbiota-reshaping effects of ginsenoside Rg1 were evaluated. Ginsenoside Rg1 acts as an immune-enhancing agent to increase spleen index and the number of T, B and dendritic cells in dexamethasone (Dex)-treated mice. Ginsenoside Rg1 also increased the production of sIgA and regulated the expression of interleukin 2 (IL-2), IL-4, IL-10 and IFN-γ. Meanwhile, Rg1 administration regulated the structure of intestinal microbiota. The relative abundance of mouse intestinal microbial groups, such as Alistipes, Ruminococcaceae, Lachnospiraceae, and Roseburia were increased by Rg1 administration, whereas a decrease in the potential pathogens like Helicobacteraceae, Dubosiella, Mycoplasma, Alloprevotella, Allobaculum was observed. Moreover, Rg1 metabolites of Lachnospiraceae bacterium enhanced the proliferation of CD4+ T cells and T regulatory (Treg) cells. Ginsenoside Rg1 improved the inflammatory condition of the colonic tissue and repaired the destructed mucosal barrier. This study suggested that Rg1 strengthens immunity with regulating the homeostasis of intestinal microbiota in mice.
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