Enterobacterial Repetitive Intergenic Consensus-polymerase Chain Research Articles

Molecular typing of clinical multidrug-resistant Klebsiella pneumoniae isolates.

Klebsiella pneumoniae is an opportunistic pathogen which is an important cause of hospital-acquired and antibiotic resistance infections. Therefore, this study aimed to determine the frequency of resistance to antibiotics, as well as the molecular typing of the associated isolates, and compare multiple-locus VNTR analysis (MLVA) and Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR) methods to specify the degree to which distinctions can be separated from each other. One hundred K. pneumoniae isolates were obtained from different sources of infections from patients admitted to hospitals. Antibiotic susceptibility testing was then performed by applying the Kirby-Bauer disk diffusion method. Typing of K. pneumoniae was done by utilizing MLVA and ERIC-PCR methods. Eighty-six multidrug-resistant (MDR) K. pneumoniae isolates were identified, which resistance to ampicillin, trimethoprim/sulfamethoxazole, and ceftriaxone was the most frequent in the considered isolates (100, 93, and 93%, respectively). A total of 50 different antibiotic susceptibility patterns were observed among the MDR K. pneumonia, with the most frequent pattern being resistance to all antibiotics (12.79%) and resistance to all antibiotics except amikacin (10.47%). The isolates were then divided into 37 different MLVA types and seven clonal complexes were obtained from the minimum spanning tree analysis. Finally, the isolates were assigned to 38 different ERIC types. The discriminatory power of MLVA and ERIC methods also showed a value of 0.958, and 0.974. Both PCR-typing methods with phenotypic patterns can be useful for the epidemiological typing of K. pneumoniae isolates with the highest performance in discriminating isolates.

Serotype and genotyping of <i>Salmonella</i> sp. isolated from street foods in N’Djaména, Chad

Group foodborne illness infections with Salmonella are often caused by the simultaneous consumption by several people of heavily contaminated food. The objective of this work was to determine the phylogenetic relationships between dietary strains of Salmonella sp. isolated from our samples and confirmed clinical strains. A total of 447 samples were collected and analyzed using standard food microbiology methods. Enterobacterial Repetitive Intergenic Consensus-Polymerase chain Reaction (ERIC-PCR) technique allowed confirmation that all our strains belong to the genus Salmonella. From ten (10) strains characterized, eight (8) different genotype profiles were identified. The different DNA fragments of the isolates were generated by ERIC-PCR and then revealed on the agarose gel and had bands ranging from 2 to 6 bands with sizes between 150 and 1500 bp. The two food strains of S. Mbadaka (1 and 2) presented identical profiles. However, it is noted that two (2) strains of S. Anatum had different ERIC-PCR profiles. There is also a very high resemblance between the strain of S. Anatum (strain 5) and the confirmed clinical strains (H5: Salmonella Typhi). The presence of risky germs in the food analyzed poses a public health problem and should call on the competent authorities and prompt the taking of corrective measures.

Pathogenicity assessment of Arcobacter butzleri isolated from Canadian agricultural surface water

BackgroundWater is considered a source for the transmission of Arcobacter species to both humans and animals. This study was conducted to assess the prevalence, distribution, and pathogenicity of A. butzleri strains, which can potentially pose health risks to humans and animals. Cultures were isolated from surface waters of a mixed-use but predominately agricultural watershed in eastern Ontario, Canada. The detection of antimicrobial resistance (AMR) and virulence-associated genes (VAGs), as well as enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) assays were performed on 913 A. butzleri strains isolated from 11 agricultural sampling sites.ResultsAll strains were resistant to one or more antimicrobial agents, with a high rate of resistance to clindamycin (99%) and chloramphenicol (77%), followed by azithromycin (48%) and nalidixic acid (49%). However, isolates showed a significantly (p < 0.05) high rate of susceptibility to tetracycline (1%), gentamycin (2%), ciprofloxacin (4%), and erythromycin (5%). Of the eight VAGs tested, ciaB, mviN, tlyA, and pldA were detected at high frequency (> 85%) compared to irgA (25%), hecB (19%), hecA (15%), and cj1349 (12%) genes. Co-occurrence analysis showed A. butzleri strains resistant to clindamycin, chloramphenicol, nalidixic acid, and azithromycin were positive for ciaB, tlyA, mviN and pldA VAGs. ERIC-PCR fingerprint analysis revealed high genetic similarity among strains isolated from three sites, and the genotypes were significantly associated with AMR and VAGs results, which highlight their potential environmental ubiquity and potential as pathogenic.ConclusionsThe study results show that agricultural activities likely contribute to the contamination of A. butzleri in surface water. The findings underscore the importance of farm management practices in controlling the potential spread of A. butzleri and its associated health risks to humans and animals through contaminated water.

Sociodemographic distributions and molecular characterization of colonized Enterococcus faecium isolates from locality hospitals in Khartoum, Sudan.

Enterococcus faecium is an opportunistic pathogen of humans with diverse hosts, encompassing animals as well as human beings. In the past twenty years, there has been a rise in the instances of nosocomial infections that are linked to antibiotic-resistant Enterococcus faecium. The acquisition of diverse antimicrobial resistance factors has driven the global development of robust and convergent adaptive mechanisms within the healthcare environment. The presence of microorganisms in hospitalized and non-hospitalized patient populations has been significantly aided by the facilitation of various perturbations within their respective microbiomes. This study aimed to determine the antimicrobial profile, demographic and clinical characteristics, along with the detection of virulence encoding genes, and to find out the clonal genetic relationship among colonized E. faecium strains. A hospital-based cross-sectional study was carried out between October 2018 and March 2020 at four Khartoum locality hospitals in Sudan. The study comprised a total of 108 strains of E. faecium isolated from patients admitted to four locality hospitals in Khartoum. A self-structured questionnaire was used to gather information on sociodemographic traits. Data were analyzed using chi-square test. In all cases, P value ≤ 0.05 with a corresponding 95% confidence interval was considered statistically significant. Moreover, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) was utilized to assess the prevalence of clonal relationships, and the gel was analyzed using CLIQS software. In this study, the isolation rate of colonized E. faecium strains was 108/170 (63.5%). The colonization of E. faecium and its association with various sociodemographic and clinical features was examined. 73 (67.6%) of patients had multidrug-resistant (MDR), and 22 (20.4%) had extensively drug-resistant (XDR), 73 (67.6%) of patients engaged in self-medication practices. Eighty patients (74.1%) were non-adherence to prescribed antibiotics, while 70 (64.8%) patients reported recent antibiotic usage within the 3 months. The present study suggests that demographic factors may not be significantly associated with the incidence of E. faecium infection except for patients who had a prior history of antibiotic use (P≤0.005). The analysis of virulence genes showed a high prevalence of asa1 gene (22.2%) among strains. In ERIC-PCR the genetic relatedness of E. faecium showed seven identical clusters (A-G) with 100% genetic similarity. This implies clonal propagation in hospitals and communities. This study found that the incidence of E. faecium isolated from locality hospitals in Khartoum was likely due to the spread of E. faecium clones, thereby highlighting the need for intensifying infection control measures to prevent the spreading of nosocomial infection.

Molecular Typing of Multidrug-Resistant Acinetobacter baumannii Isolates from Clinical Specimens by ERIC-PCR and MLVA.

Acinetobacter baumannii, a Gram-negative and oxidase-negative bacterium, is a major cause of nosocomial infections, leading to high mortality rates in hospitalized patients. The use of 2 prominent molecular typing methods (i.e., enterobacterial repetitive intergenic consensus-polymerase chain reaction [ERIC-PCR] and multiple-locus variable-number tandem repeat [VNTR] analysis [MLVA]) for genotyping A. baumannii isolates has proven to be an effective approach in assessing the clonal relation of these isolates and managing their outbreaks. A total of 100 A. baumannii isolates were collected from immunocompromised patients hospitalized in the intensive care unit (ICU) of a hospital in Zanjan City, Iran. Their antibiotic resistance ability (especially aminoglycoside resistance) was studied by disc diffusion tests. The genetic typing of A. baumannii was studied using ERIC-PCR and MLVA methods. All isolates were resistant to 3 or more antibiotics and regarded as multidrug-resistant (MDR). Additionally, 32% of the isolates were resistant to all antibiotics tested, and 91% were extensively drug-resistant (XDR). The increased rate of aminoglycoside-resistant A. baumannii in ICU patients, with an increased incidence of aminoglycoside-modifying enzymes of aac (6')-Ib, ant (3″)-I, and aph (2″)-Id. ERIC-PCR has likewise shown an increased level of diversity in A. baumannii isolates. According to the ERIC-PCR patterns, isolates were classified as 4 clusters, while according to the MLVA patterns, isolates were classified as 9 distinct clusters. ERIC-PCR and MLVA assays serve as useful genotyping methods to assess the genetic variety or clonal relatedness of A. baumannii isolates.

Primary Carrier Status and Alteration in the Colonization of the Extended-Spectrum β-Lactamase Producing Enterobacteriaceae Among Children in Pediatric Intensive Care Unit During the Hospital Stay

Background: Widespread and inappropriate use of antibiotics has led to an increase in antibiotic-resistant bacteria worldwide. Extended-spectrum β-lactamases (ESBLs) are among the most important resistance mechanisms in members of Enterobacteriaceae, which can pose a threat to patients. Objectives: This study aimed to investigate the carrier status and alteration in the fecal transmission of ESBL-producing Enterobacteriaceae (ESBL-E) on admission and during the hospital stay, as well as its correlation with the usage of antibiotics among children in a pediatric intensive care unit (PICU). Molecular typing between the primary and secondary isolates was done to detect the homotypic clonal strains. Methods: Demographic and medical data of PICU children were collected, and the carrier status of ESBL-E was investigated in pairs of their rectal swab samples at the admission and discharge time. Detection of ESBL phenotype and antimicrobial susceptibility to 12 antibiotics were performed by double-disk synergy and disc diffusion methods, respectively. Polymerase chain reaction for detection of blaTEM, blaSHVblaPER, blaCTX-M, and blaVEB genes was performed using specific primers. The phylogenetic relations were analyzed by the enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) method. Results: Extended-spectrum β-lactamase-producing Enterobacteriaceae was detected in 48% of the samples at admission and 42% at discharge time. The highest frequency of resistance was observed in cephazolin, amoxicillin-clavulanic acid, and ampicillin. Children with a history of meropenem administration showed a significantly higher frequency of meropenem resistance Enterobacteriaceae in their samples. Moreover, the administration of metronidazole increased the isolation of ESBL-Escherichia species in hospitalized children. The most common gene associated with the ESBL phenotype was blaCTX-M, while blaPER and blaVEB were not detected in the ESBL-E isolates. The phylogenetic analysis did not confirm the occurrence of the cross-transmission of ESBL-E in the patients during hospitalization. Conclusions: Our results showed a high frequency of ESBL-E in the feces of children upon admission to the PICU, which did not change significantly during the hospital stay. Although the prescription of metronidazole showed an association with the enrichment of ESBL-E due to observed diversity in the molecular types and resistance phenotypes of the isolates, the community seems to be the primary source of ESBL-E transmission in children. Further investigations are needed to understand the role of hospital stay in the colonization and enrichment of ESBL-E in the intestinal tract of children and their association with infections during the medical interventions in the PICU.

Evidence-Based Interventions to Reduce the Incidence of Common Multidrug-Resistant Gram-Negative Bacteria in an Adult Intensive Care Unit.

Background Multidrug-resistant Gram-negative bacteria (MDR-GNB) present a significant and escalating hazard to healthcare globally. Context-specific interventions have been implemented for the prevention and control of MDR-GNB in several healthcare facilities. The objective of this study was to implement and evaluate the effectiveness of evidence-based interventions in the incidence and dissemination of MDR-GNB. Methods This was a pre-and post-intervention study conducted in three phases at King Abdulaziz Medical City Jeddah, Saudi Arabia. During Phase-1, the data on each of the four MDR-GNB (Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli) were collected prospectively. Genomic fingerprinting was performed on isolates using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) to determine clonality and establish a link between different strains within and between the hospital wards/units. In the second phase, targeted interventions were implemented in the adult intensive care unit (ICU) based on previously determined risk factors and includedthe education of healthcare workers on hand hygiene, disinfection of patients' surrounding, daily chlorhexidine baths, and disinfection rooms on discharge with hydrogen peroxide fogging after MDR-GNB patients were discharged. An antibiotic restriction protocol was simultaneously implemented as part of the hospital antibiotic stewardship program. In the third phase, the effectiveness of the interventions was evaluated by comparing the incidence rate and clonality (using ERIC-PCR genetic fingerprints) of MDR-GNB before and after the intervention. Results A significant reduction of MDR-GNB was observed in Phase-2 and Phase-3 compared with Phase-1. The mean incidence rate of MDR-GNB per 1000 patient days in Phase-1 (pre-intervention) was 11.08/1000, followed by 6.07 and 3.54/1000 in Phase-2 and Phase-3, respectively. A statistically significant reduction was observed in the incidence rate of MDR-GNB in the adult ICU (P=0.007), whereas no statistically significant decrease (P=0.419) was observed in areas other than the adult ICU. Two A. baumannii strains appear to be circulating within the ICU environment with reduced frequency in Phase-2 and Phase-3 compared to Phase-1. Conclusion There was a significant reduction in the incidence of MDR-GNB in the adult ICU due to the successful implementation of both infection control and stewardship interventions, albeit challenging to ascertain the relative contribution of each.

Phenotypic and genetic screening of Klebsiella pneumoniae isolates from human UTI patients for beta-lactamases and their genetic diversity analysis by ERIC and REP PCRs.

Klebsiella pneumoniae is one of the major nosocomial pathogens responsible for pneumoniae, septicaemia, liver abscesses, and urinary tract infections. Coordinated efforts by antibiotic stewardship and clinicians are underway to curtail the emergence of antibiotic-resistant strains. The objective of the present study is to characterize K. pneumoniae strains through antibiotic resistance screening for production of beta-lactamases (β-lactamases) such as extended spectrum beta lactamases (ESBLs), AmpC β-lactamases, and carbapenemases by phenotypic and genotypic methods and genetic fingerprinting by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and repetitive element palindromic PCR (REP-PCR). A total of 85 K. pneumoniae strains isolated from 504 human urinary tract infections (UTI) were used in this study. Only 76 isolates showed positive in phenotypic screening test (PST), while combination disc method (CDM) as phenotypic confirmatory test (PCT) confirmed 72 isolates as ESBL producers. One or more β-lactamase genes were detected by PCR in 66 isolates (91.66%, 66/72) with blaTEM gene being the most predominant (75.75%, 50/66). AmpC genes could be detected in 21 isolates (31.8%, 21/66) with FOX gene being the predominant (24.24%, 16/66), whereas NDM-I was detected in a single strain (1.51%, 1/66). Genetic fingerprinting using ERIC-PCR and REP-PCR revealed wide heterogeneity among β-lactamase producing isolates with discriminatory power of 0.9995 and 1, respectively.

Evaluation of ERIC-PCR method for determining genetic diversity among Escherichia coli isolated from human and retail imported frozen shrimp and beef

There is a global concern and increasing reports regarding foodborne disease infections associated with consuming contaminated vegetables, seafood, meat, and poultry products. Among foodborne bacterial pathogens globally, Salmonella, Escherichia coli, and Shigella were the most frequently implicated in causing food poisoning infections in children and adults. In Saudi Arabia, the consumption rates of imported fresh fruits, vegetables, seafood, and meat products are considered high. Therefore, the development of simple PCR based DNA fingerprinting methods is essential to track the source and route of microbial contamination among imported frozen meat and seafood products. A total of 38 E. coli strains were subtyped using ERIC1R, ERIC2, and a pair combination (ERIC1R + ERIC2) to generate genomic fingerprinting. The three Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR)-based primers were generated in 26, 24, and 16 different genotypes while using ERIC1R, ERIC2, and ERIC1R + ERIC2, respectively. The Discrimination Index values obtained by ERIC1R, ERIC2, and ERIC1R + ERIC2 were 0.976, 0.965, and 0.903, respectively. ERIC1R and ERIC2 primers had the best discriminatory ability and typeability value and proved suitable for investigating genetic analysis among the population of E. coli strains. At the same time, the ERIC1R + ERIC2 primer pair has average discriminatory power and typeability value for differentiating E. coli strains. These results suggest that subtyping using ERIC1R and ERIC2 primer is a more reliable and rapid typing strategy for E. coli strains.

High-Frequency Detection of fosA3 and bla CTX-M-55 Genes in Escherichia coli From Longitudinal Monitoring in Broiler Chicken Farms.

Considering the worrying emergence of multidrug resistance, including in animal husbandry and especially in food-producing animals, the need to detect antimicrobial resistance strains in poultry environments is relevant, mainly considering a One Health approach. Thus, this study aimed to conduct longitudinal monitoring of antimicrobial resistance in broiler chicken farms, with an emphasis on evaluating the frequency of resistance to fosfomycin and β-lactams. Escherichia coli was isolated from broiler chicken farms (cloacal swabs, meconium, poultry feed, water, poultry litter, and Alphitobius diaperinus) in northern Paraná from 2019 to 2020 during three periods: the first period (1st days of life), the second period (20th to 25th days of life), and third period (40th to 42nd days of life). Antibiogram tests and the detection of phenotypic extended-spectrum β-lactamase (ESBL) were performed, and they were confirmed by seaching for genes from the blaCTX–M group. The other resistance genes searched were mcr-1 and fosA3. Some ESBL blaCTX–M–1 group strains were selected for ESBL identification by sequencing and enterobacterial repetitive intergenic consensus-polymerase chain reaction analysis. To determine the transferability of the blaCTX–M–1– and fosA3-carrying plasmids, strains were subjected to conjugation experiments. A total of 507 E. coli were analyzed: 360 from cloacal swabs, 24 from meconium samples, 3 from poultry feed samples, 18 from water samples, 69 from poultry litter samples, and 33 from A. diaperinus samples. Among the strain isolate, 80% (406/507) were multidrug-resistant (MDR), and 51% (260/507) were ESBL-positive, with the blaCTX–M–1 group being the most frequent. For the fosA3 gene, 68% (344/507) of the strains isolated were positive, deserves to be highlighted E. coli isolated from day-old chickens (OR 6.34, CI 2.34–17.17), when compared with strains isolated from other origins (poultry litter, A. diaperinus, water, and poultry feed). This work alerts us to the high frequency of the fosA3 gene correlated with the CTX-M-1 group (OR 3.57, CI 95% 2.7–4.72, p < 0.05), especially the blaCTX–M–55 gene, in broiler chickens. This profile was observed mainly in day-old chicken, with a high percentage of E. coli that were MDR. The findings emphasize the importance of conducting longitudinal monitoring to detect the primary risk points during poultry production.

Isolation and molecular characterization of nutritionally potent Arthrospira maxima from Indian paddy field

Arthrospira maxima (A. maxima) is a cyanobacterium renowned for its usage as food and feed supplements as a potential source of functional ingredients for developing nutraceutical foods of natural origin. The Indian paddy fields, which can naturally produce eco-friendly cyanobacterial mats soon after receiving monsoon rain, were studied for isolation and molecular confirmation of Arthrospira and exploration of its nutritional profile. First, the collected cyanobacterial mat was processed for isolation of pure culture. After that, axenic culture was maintained in Zarrouk's medium at 27 ± 2 °C under the photosynthetically active radiation (PAR) of 75 μmol photon m−2 s−1 with a 16/8 h of light/dark period in laboratory condition. Morphologically proven pure culture of A. maxima was subsequently analyzed for its genomic stability using Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR) and confirmed by targeting 16S ribosomal RNA partial gene sequencing.Further confirmed and pure A. maxima extract was processed to find out its nutraceutical values (amino acids, fatty acid, vitamin and chlorophyll content) by using High-performance liquid chromatography (HPLC) and Gas chromatograph (GC) technique. Results showed that identified strain was confirmed as A. maxima, and its partial gene sequences had been submitted to NCBI to get a unique accession number (GenBank: KM407008.1.). The study explores the new strain of A. maxima as an habitant from the Indian paddy field; it may be considered a potential candidate for industrial biomass production at a large scale.

Escherichia coli Clonal Variability Based on Genetic Diversity Pattern with Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction Methods for Traveler’s Diarrhea Cases in Bali

BACKGROUND: Bali is a favorite tourism destination in the world. As a major tourist destination, the incidence of illness that afflicts tourists greatly affects the image of tourism. Diarrhea is a health problem that is most often experienced and is a major obstacle for foreign tourists when traveling, especially to Bali. Escherichia coli (E. coli) bacteria cause diarrhea more often than viruses in some developing countries. Genetic differences can affect the characteristics of E. coli, especially in relation to the medical field. AIM: We would like to assess the genetic diversity of the different pathogenic E. coli from various clinical isolates including those from traveler’s diarrhea in Bali, Indonesia. MATERIALS AND METHODS: One of the molecular techniques used in this study is to use enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The sample in this study was the feces of foreign tourists with traveler’s diarrhea in Bali. This study carried out research procedures in the form of Isolation of E. coli genome DNA from culture, amplification of E. coli 16S rRNA encoding genes, sequencing of E. coli 16S rRNA encoding genes, phylogenetic tree construction, and then analysis of E. coli genetic diversity with ERIC-PCR sequences. RESULTS: The results showed that the ERIC-PCR method was more discriminatory than other methods to analyze the genetic diversity of E. coli from fecal samples of patients with traveler’s diarrhea. It was found that clonal variability based on the genetic similarity of all sample E. coli isolates varied from 0% to 100%. CONCLUSIONS: This shows that the source of transmission and the strains of E. coli that cause it comes from diverse populations.

Spoligotyping and polymerase chain reaction based mycobacterium bovis strains typing with methods (enterobacterial repetitive intergenic consensus-polymerase chain reaction, randomly amplified polymorphic dnas-polymerase chain reaction and out polymerase chain reaction).

In this study, it was aimed to investigate Mycobacterium bovis strains isolated from lungs and lymph nodes of slaughtered animals on clonal level by using different methods such as spoligotyping, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), randomly amplified polymorphic DNAs (RAPD-PCR) and OUT-PCR. Comparative evaluation of these methods was further conducted. A total of 38 M. bovis isolates were evaluated in the study. DNA isolation of all M. bovis strains isolated from pruvat free Löwenstein Jensen medium was done by boiling method for ERIC-PCR, RAPD-PCR, and OUT PCR. Mickle device was used for DNA isolation for spoligotyping method. In 38 M. bovis isolates examined in our study, 4 different groups were determined by spoligotyping and RAPD-PCR test methods, and 5 different groups were detected in ERIC-PCR tests. In the OUT-PCR tests, the band which provides sufficient type separation was not observed. ERIC-PCR, RAPD-PCR, and OUT-PCR methods are easily applicable, simple, and relatively inexpensive methods for evaluating the differences between origins in the typing of M. bovis. The tests need to be evaluated in more detail with extensive studies.

Elucidating the resistance repertoire, biofilm production, and phylogenetic characteristics of multidrug-resistant Escherichia coli isolated from community ponds: A study from West Bengal, India.

This study details about the phenotypic and molecular characteristics of multidrug-resistant (MDR) Escherichia coli in the fresh community pond water (n = 257) collected from three districts of West Bengal, India. In total, 57 isolates were MDR of which 38 emerged as extended spectrum and 7 as AmpC-type β-lactamase producers in phenotypic assay. Among β-lactamase genes, blaCTXM-1was predominant (87.71%) followed by blaAmpC (77.2%) and blaTEM-1 (22.8%). Six MDR strains carried metallo-β-lactamase (MBL, blaNDM-1) gene. Tissue culture plate assay confirmed strong biofilm (SP) production in four MDR and one non-MDR isolates. In PCR-based replicon typing (PBRT), multiple plasmids of diverse replicon types (Frep, FIB, I1, FIA, K/B, HI1, and Y) were identified. The enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR)-based phylogenetic analysis revealed a high degree of genetic divergence among the MDR isolates. Multiplex PCR-based phylogrouping categorized 11 isolates as virulent (B2/D/F), which carried blaCTXM-1 gene and three had blaNDM-1 gene. Relative transcriptional activity of AcrAB efflux pump was significantly elevated among the SP and MBL producers. The presence of MDR E.coli isolates, particularly those resistant to carbapenem, in pond water used for daily domestic and household work, is a cause of concern as these pathogens may sneak into human food chain causing life-threatening infections. PRACTITIONER POINTS: Multidrug-resistant biofilm producing E. coli isolated from community pond water. A few of them were carbapenem-resistant and belonged to virulent (B2/D) types. Expression of AcrAB efflux pumps was found significantly elevated among biofilm producers and carbapenem-resistant population.

Antibiotics Combinations and Chitosan Nanoparticles for Combating Multidrug Resistance Acinetobacter baumannii.

BackgroundSuccessful treatment of Acinetobacter (A.) baumannii-associated infection is complicated by the emergence of multidrug resistance (MDR), particularly in clinical settings. This urges searching for new alternatives to encounter such health problem.AimThis study aimed to evaluate certain antibiotic combinations and CNPs either alone or in combination of some selected antibiotics for the purpose of combating MDR A. baumannii clinical isolates.MethodsA total of 51 A. baumannii clinical isolates were recovered from discharged clinical specimens of the Clinical Microbiology Central Laboratory of AL Kasr Al Aini hospital, Cairo, Egypt. Conventional standard Lab tests were used for identification followed by recA gene testing for confirmation. Antimicrobial susceptibility tests were conducted out according to CLSI guidelines. Genotypic analysis using Enterobacterial Repetitive Intergenic Consensus-polymerase chain reaction (ERIC-PCR) of the respective isolates showed that they were clustered in nine clones. The prepared CNPs were characterized by dynamic light scattering and HR-transmission electron microscope imaging. Antibiotic combinations and co-effect of CNPs with some selected antibiotics (either each alone or in combination of two) were evaluated using the Checkerboard microdilution and minimum inhibitor concentration decrease factor (MDF) methods, respectively.ResultsThe recovered 51 A. baumannii clinical isolates were MDR (100%) of these 92% (47/51) were extensively drug resistance (XDR). Combinations of colistin (CT)+meropenem (MEM) and MEM+tigecycline (TGC) showed synergism in 77.7% and 44.4% and additive effects in 22.3% and 55.6% of the tested MDR A. baumannii isolates (n=51), respectively. However, CT+TGC combination showed antagonism. CNPs exhibited good inhibitory activity (inhibition zones ranged from 24 to 31 mm) against selected nine MDR A. baumannii isolates (one isolate from each clone). The MIC of CNPs at concentrations (ranging from 1 to 5 mg/mL) were from 0.16 to 0.25 mg/mL, indicating good in vitro antimicrobial activities. CNPs (5 mg/mL) when combined with CT, TGC or MEM, CT+MEM and TGC+MEM significantly increased the susceptibilities of the MDR A. baumannii isolates to these antibiotics by 88.8%, 66.6%, 100%, 77.7%, and 44.4%, respectively. No significant effects were observed when CNPs (5 mg/mL) were combined with CT+TGC.ConclusionThe current study demonstrated the significant in-vitro activities of CNPs either alone or in combination with CT, TGC or MEM, CT+MEM and TGC+MEM and the successful combinations of MEM either with CT or with TGC against the MDR A. baumannii pathogens. However, further in vivo studies should be conducted to verify such activities and their potential use in human.

Prevalence and Characteristics of Metallo-beta-Lactamase-positive and High-risk Clone ST235 Pseudomonas aeruginosa at Ardabil Hospitals

Background: Carbapenems are the most commonly administered drugs for the treatment of multidrug-resistant Pseudomonas aeruginosa (MDR P. aeruginosa) infections. However, carbapenem-resistant P. aeruginosa is spreading rapidly and has led to a new threat to human health worldwide. Objectives: The current study aimed to determine the prevalence of imipenem-resistant P. aeruginosa, detect metallo-β-lactamase (MBL)-producer isolates, and evaluate their clonal relationships in strains isolated from patients referring to the hospitals of Ardabil city, Iran. Methods: The resistance rate to imipenem was evaluated using the disk diffusion method. Double-disk synergy test and PCR technique were used for phenotypic and genotypic screening of MBL-positive P. aeruginosa, respectively. Ultimately, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and multilocus sequence typing (MLST) methods were used for assessing clonal relatedness among the isolates. Results: The prevalence of imipenem-resistant P. aeruginosa strains was estimated at 57.1% (48 out of 84 isolates). In addition, 45 (93.7%) out of 48 imipenem-resistant P. aeruginosa isolates were phenotypically screened as MBL-positive, among which 16 (35.5%) and three (6.6%) isolates harbored blaIMP and blaVIM-1 genes, respectively. However, blaNDM, blaSIM-2, blaSPM, and blaGIM-1 genes were not detected in this study. MBL-producing P. aeruginosa strains were divided into 42 ERIC-PCR types. Based on the results of MLST, P. aeruginosa ST235 was the only identified sequence type. Conclusions: Our results revealed a high and alarming prevalence of imipenem-resistant and blaIMP-positive P. aeruginosa ST235 at Ardabil hospitals. Continuous monitoring is essential to control the further spread of this highly virulent and drug-resistant clone.

Genotype and virulence gene analyses of Bacillus cereus group clinical isolates from the Chinese softshell turtle (Pelodiscus sinensis) in Taiwan.

Chinese softshell turtles (Pelodiscus sinensis) (CST) are susceptible to infections by bacteria belonging to the Bacillus cereus group (Bcg). Bcg includes several closely related species, two of which, B. cereus and B. thuringiensis, are pathogens of aquatic animals or insects. In the present study, we collected 57 Bcg isolates obtained from diseased CST from 2016 to 2019 in Kaohsiung and Pingtung, the areas with the most CST farms in Taiwan. All isolates were divided into four genotypes with two restriction enzymes, SmaI and NotI, by pulsed-field gel electrophoresis and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). Representative isolates from each genotype were subjected to phylogenetic tree analysis using 16S rDNA and pyruvate carboxylase genes as phylogenetic markers, and these CST isolates appeared in different clades. PCR was performed targeting six selected virulence genes, four of which were detected in CST isolates, including cytotoxin K (1/57), hblC of the haemolysin BL complex (46/57), nheA of the non-haemolytic enterotoxin complex (52/57) and enterotoxin FM (57/57), whereas cereulide synthetase and cereulide peptide synthase-like genes were not detected in any isolates.

Molecular epidemiology of vancomycin-resistant Enterococcus faecium clinical isolates in a tertiary care hospital in southern Thailand: a retrospective study

ObjectiveVancomycin-resistant enterococci are nosocomial pathogens that are responsible for commonly causing healthcare-associated infections, and they exhibit increased resistance to many antimicrobials, particularly to vancomycin. The epidemiological data available on vancomycin-resistant enterococci (VRE) in Thailand are inadequate.MethodsUsing enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), this study investigated genes that encode antimicrobial resistance and genetic relatedness to further understand VRE prevalence. Ninety VRE isolates were collected between 2011 and 2019 from a tertiary care hospital in southern Thailand. Antimicrobial susceptibility was determined using the disk diffusion method and E-test methods. Multiplex PCR was performed to detect the van gene and virulence genes.ResultsThe study showed a high prevalence of diverse multidrug-resistant VRE strains. The prevalence of VRE infection was the highest in 2014 (28 isolates, 39.4%). VRE were mostly found in the urogenital tract (26 isolates, 28.9%), followed by the digestive tract (20%), body fluid, i.e., pancreatic cyst fluid, peritoneal dialysis fluid, Jackson–Pratt (JP) drain (20%), and blood specimens (10%). Patients in medical and surgical wards had 71.1% multi-drug-resistant and 28.9% extensively drug-resistant (XDR) VRE strains, respectively. The most prevalent antibiotic resistance was to ampicillin (74.4%). Susceptibility to gentamicin and meropenem were similar (7% and 10%, respectively). Four isolates (4.4%) were resistant to colistin. Only vanA was detected among the strains. The virulence gene test showed that the detection rates of enterococcal surface protein (esp) and hyaluronidase (hyl) genes were 91.1% and 5.6%, respectively. According to ERIC-PCR analysis, 51 of 90 strains had clonality, with a similarity rate of 95%.ConclusionsWe conclude that there is a need to implement infection control practices and active surveillance. Molecular techniques can effectively detect antibiotic-resistant genes, which would allow monitoring to control VRE infection in hospitals.

Prevalence, virulence-gene profiles, antimicrobial resistance, and genetic diversity of human pathogenic Aeromonas spp. from shellfish and aquatic environments

Aeromonas are found in various habitats, particularly in aquatic environments. This study examined the presence of the most common human pathogenic Aeromonas species (Aeromonas caviae, A. hydrophila, and A. veronii) in surface water, sea water, and shellfish. The detection rates in fishing harbour seawater, shellfish farming seawater, and a river basin were 33.3%, 26.4%, and 29.4%, respectively, and high prevalence was observed in summer. The detection rates in shellfish procured from a fish market and shellfish farm were 34.9% and 13.3%, respectively. The most abundant species of human pathogenic Aeromonas detected via water sampling was A. caviae, whereas that obtained via shellfish sampling was A. veronii. The prevalence of human pathogenic Aeromonas in river water was lower in fishing harbours and in the estuary shellfish farming area. Here, 25 isolates of human pathogenic Aeromonas species were isolated from 257 samples and divided among 16 virulence profiles. The high virulence gene-carrying isolates (more than six genes) belonged to A. hydrophila. The shellfish-sourced isolates had the highest detection rates of act, aerA, and fla genes than of other virulence genes, and vice versa for seawater-sourced isolates. The Aeromonas isolates showed high levels of resistance to ampicillin-sulbactam; however, none were resistant to cefepime, ciprofloxacin, or gentamicin. The incidence of multiple drug resistance (MDR) in Aeromonas isolates was 20%. In this study, phylogenetic analysis with 16S rRNA sequencing, biochemical tests and enterobacterial repetitive intergenic consensus-polymerase chain reaction fingerprinting facilitated the distinct categorisation of three species of human pathogenic Aeromonas isolates. In addition, A. veronii isolates from the same geographical area were also concentrated in the same cluster. This study provides information on the risk of infection by Aeromonas with MDR and multiple virulence genes isolated from shellfish and aquatic environments.

Antibiotic resistance and determination of resistant genes among cockle (Anadara granosa) isolates of Vibrio alginolyticus.

A total of 24 strains of Vibrio alginolyticus were isolated from cockles (Anadara granosa) and identified for VibA and gyrB genes. All V. alginolyticus isolates were then tested against nine different antibiotics. In this study, the highest percentage of antibiotic resistance was obtained against penicillin (37.50%), followed by ampicillin, vancomycin (12.50%) and erythromycin (8.33%). All of V. alginolyticus isolates were susceptible against streptomycin, kanamycin, tetracycline, chloramphenicol and sulfamethoxazole. Polymerase chain reaction (PCR) assay has confirmed the presence of four antibiotic resistance genes of penicillin (pbp2a), ampicillin (blaOXA), erythromycin (ermB) and vancomycin (vanB). Out of 24 V. alginolyticus isolates, 2 isolates possessed the tdh-related hemolysin (trh) (strains VA15 and VA16) and none for the thermostable direct hemolysin (tdh) gene. Both strains of the tdh-related hemolysin (trh) were susceptible to all antibiotics tested. The multiple antibiotic resistance (MAR) index ranging between 0.2 and 0.3 with 5 antibiograms (A1-A5) was observed. Combination of enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and antibiotic resistance indicated 18 genome types which showed genetic heterogeneity of those V. alginolyticus isolates. The results demonstrated the presence of V. alginolyticus strain found in cockles can be a potential risk to consumers and can contribute to the deterioration of human health in the study area. Thus, it is essential for local authority to provide the preventive measures in ensuring the cockles are safefor consumption.