(GTG)5-PCR fingerprinting of multi-drug resistant Escherichia coli bacteria isolates from hospital in Ouagadougou, Burkina Faso

Genotyping of Corynebacterium pseudotuberculosis isolates using PCR-based DNA fingerprinting methods

Phenotypic typing methods are often time consuming and do not adequately discriminate among the strains involved. Innovative molecular techniques can perform direct typing by analyzing DNA and are becoming widespread as important tools for bacterial typing, molecular epidemiology and molecular systematization. The aim of this study was to genotype Corynebacterium pseudotuberculosis strains using PCR-based DNA fingerprinting methods and to evaluate the methods comparatively. Within the scope of the study, 17 C. pseudotuberculosis strains were analyzed. The strains were genotyped by enterobacterial repetitive intergenic consensus (ERIC)-PCR using ERIC2 primer; by random amplified polymorphic (RAPD) DNA-PCR using primers P5, P6, P11, P14, P16, P21 and M13; and by (GTG)5-PCR using (GTG)5 primer. The discrimination power and confidence intervals of the methods were calculated based on the genotyping results using each primer. All strains produced amplification products with the primers used for genotyping. As a result of genotyping with ERIC2, P14, P11, (GTG)5, P21, P5, M13, P6 and P16 primers, the discrimination powers (confidence intervals) were calculated as 0.8603(0.858-0.862), 0.7132(0.709-0.716), 0.6838(0.668-0.699), 0.6397(0.623-0.656), 0.5809(0.560-0.601), 0.3235(0.293-0.353), 0.1176(0.081-0.153), 0.1176(0.081-0.153) and 0.1176(0.081-0.153), respectively. As a result of the comparative evaluation of the results, it was observed that ERIC2 and P14 primers had high discrimination power and confidence interval in genotyping C. pseudotuberculosis strains, while M13, P6 and P16 primers were insufficient in genotyping of strains. It was concluded that genotyping with ERIC2 and P14 primers can be used reliably in investigating the molecular epidemiology of infections and/or outbreaks caused by C. pseudotuberculosis.

High prevalence of multidrug resistant and extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolated from urinary tract infections in the West region, Cameroon

BACKGROUND

Antimicrobial resistance remains a worldwide health problem with serious societal and economical repercussions. Multidrug resistant and Extended-Spectrum β-Lactamase producing-Enterobacterales (ESBL-E) are pathogens of critical public health priority that urgently require the research and development of new drugs. This study aims to determine the prevalence and characterize the genes conferring resistance to β-lactams among Escherichia coli and Klebsiella pneumoniae isolated from patients with urinary tract infections (UTIs) in the West region, Cameroon.

METHODS

A cross-sectional study was conducted among two healthcare facilities during a four-month period from February to May, 2023. All mid-stream urine samples were collected from UTIs patients. The Escherichia coli and K. pneumoniae strains were identified using Enterosystem 18R kit following the manufacturer's instructions. The antimicrobial susceptibility test (AST) was performed using the Kirby-Bauer disk diffusion method. The screening of ESBL production was done using ESBL ChromAgar medium combined with the double-disk synergy test (DDT). Antimicrobial resistance genes were detected using polymerase chain methods. The data analysis was performed using Excel 2016 and IBM SPSS version 20.

RESULTS

A total of 215 urine samples were collected and analyzed during the study period. A 31.62% (68/215) prevalence of Enterobacterales was detected with prevalence of 79.41% (54/68) and 14.70% (10/68) for Escherichia coli and Klebsiella pneumoniae respectively. The overall prevalence of ESBL-Enterobacterales was 64.70% (44/68). About 82% (36/44) of isolates were MDR and high resistance level was observed for amoxicillin + clavulanic acid and ceftazidime. The resistance genes detected were blaCTX-M, and blaTEM respectively.

CONCLUSION

The findings of this study highlight the high burden of MDR and ESBL-E. coli and K. pneumoniae isolates from UTIs. The study emphasizes the necessity of routine screening and monitoring of antimicrobial resistance in healthcare facilities and community settings. It is therefore crucial to implement antimicrobial stewardship programs in the country and infection prevention and control (IPC) measures in hospital settings.

Enhancing Mezcal Production Efficiency by Adding an Inoculant of Native Saccharomyces cerevisiae to a Standardized Fermentation Must

All traditional mezcal producers use artisan methods to produce mezcal. The low technological development in the elaboration processes results in low yield and high residual sugar concentration. First, this work optimized the concentration of initial sugars and yeast-assimilable nitrogen (YAN) in Agave durangensis juice fermentation at the laboratory level. A yield near 0.49 g EtOH/g sugar and a productivity of 1.54 g EtOH/L*h was obtained with an initial sugar concentration of 120 g/L and a YAN concentration of 0.227 g/L. Only Saccharomyces cerevisiae was found after 24 h of incubation at laboratory level, using MALDI-TOF identification. Agave durangensis heads crushed by the artisan process were used to test the inoculant performance. A mezcal yield of 11.6 kg agave/L of mezcal was obtained using the S cerevisiae inoculant and nitrogen addition, which was significantly different (p < 0.05) from other treatments. The population dynamics during fermentation were analyzed through isolation and identification using MALDI-TOF. Several yeast species (Pichia kluyveri, Torulaspora delbrueckii, Zygosaccharomyces bailii, and Saccharomyces cerevisiae) were found at the beginning of fermentation. Nonetheless, only S. cerevisiae was found at the end of fermentation. The implantation of the inoculant used was confirmed through the comparative analysis of amplification patterns of the GTG5 microsatellite of the strains identified as S. cerevisiae, finding that the inoculated strain proportion was greater than 80% of the yeast population. A technological alternative to increase the efficiency of the process is combining the addition of YAN and the inoculation of the native S. cerevisiae, which was isolated from artisan alcoholic fermentation of agave to produce mezcal.

Genotypic characterization of hypervirulent Klebsiella pneumoniae (hvKp) in a tertiary care Indian hospital

Hypervirulent Klebsiella pneumoniae (hvKp) is an emerging pathogen and causes endophthalmitis, liver abscess, osteomyelitis, meningitis, and necrotizing soft tissue infections in both immunodeficient and healthy people. The acquisition of the antibiotic resistance genes of hvKp has become an emerging concern throughout the globe. In this study, a total of 74 K. pneumoniae isolates were collected and identified by VITEK2 and blaSHV gene amplification. Out of these, 18.91% (14/74) isolates were identified as hvKp by both phenotypic string test and genotypic iucA PCR amplification. The antibiotic susceptibility revealed that 57.14% (8/14) isolates were multidrug-resistant (MDR) and 35.71% (5/14) isolates were extremely drug-resistant (XDR). All the isolates were resistant to β-lactam, β-lactamase + inhibitor groups of antibiotics, and the least resistance to colistin. Of 14 hvKp isolates, all isolates are positive for iroB (100%), followed by iutA (92.85%), peg344 (85.71%), rmpA (57.14%), and magA (21.42%) genes. Among serotypes, K1 was the most prevalent serotype 21.4% (3/14), followed by K5 14.3% (2/14). The most common carbapenemase gene was blaOXA-48 (78.57%) followed by blaNDM (14.28%) and blaKPC (14.28%) which co-carried multiple resistance genes such as blaSHV (100%), blaCTX-M (92.85%), and blaTEM (78.57%). About 92.85% (13/14) of hvKp isolates were strong biofilm producers, while one isolate (hvKp 10) was the only moderate biofilm producer. The (GTG)5-PCR molecular typing method revealed high diversity among the hvKp isolates in the tertiary care hospital. Our findings suggest that MDR-hvKp is an emerging pathogen and a challenge for clinical practice. In order to avoid hvKp strain outbreaks in hospital settings, robust infection control and effective surveillance should be implemented.

Entomotherapy as an alternative treatment for diseases due to Gram-negative bacteria in Burkina Faso

Insects are known for their harmful effects. However, they also benefit humans, animals, plants, and ecosystems. Its beneficial uses include entomophagy and entomotherapy. This study aimed to evaluate the antibacterial activity of insect extracts against Gram-negative bacteria. Antibacterial activities of thirteen crude extracts of medicinal insects were tested against twelve Gram-negative bacteria by diffusion on agar. Imipenem was used as an antibiotic for positive control. The thirteen extracts acted differently against certain Gram-negative bacteria. The largest inhibition diameter was for extracts of Cirina butyrospermi and Mylabris variabilis against Pseudomonas aeruginosa ATCC27853 and Salmonella enteritidis ATCC13076, respectively. The diameters of inhibition obtained using imipenem against these same bacterial strains were 13.0 ± 0.0 mm and 22 ± 1.0 mm, respectively. The lowest inhibition diameter (7.5 ± 0.0 mm) was obtained using Anopheles gambiae extract against Salmonella Typhimurium ATCC14028. Imipenem was active on all strains tested. The highest values of the index multi-resistance to insect's extracts were reported for Pseudomonas aeruginosa ATCC9027 and Serratia odorifera 652411. Overall, the results of this study confirmed the antibacterial activities of insects used by traditional health practitioners to treat different pathologies. Entomotherapy could be an alternative treatment for certain infectious pathologies caused by gram-negative bacteria.

Clinical and epidemiological characteristics of multi-drug resistant Enterobacterales isolated from King Fahad Hospital of the University, AlKhobar, Saudi Arabia

Multi-drug resistant (MDR) Enterobacterales remain a major clinical problem. Infections caused by carbapenem-resistant strains are particularly difficult to treat. This study aimed to assess the clinical and epidemiological characteristics of MDR Enterobacterales isolates. A total of 154 non-repetitive clinical isolates, including Escherichia coli (n = 66), Klebsiella pneumoniae (n = 70), and other Enterobacterales (n = 18), were collected from the Diagnostic Microbiology Laboratory at King Fahad Hospital of the University. Most E. coli isolates were collected from urine specimens (n = 50, 75.8%) and resistance against the third and fourth-generation cephalosporins (ceftriaxone, ceftazidime, cefixime, and cefepime) and fluoroquinolones (ciprofloxacin and levofloxacin) was assessed. Clonal relatedness analysis using enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) revealed two clones (E. coli A and B), each comprising two strains. Most K. pneumoniae samples were collected from respiratory specimens (27.1%, 20 samples), and the strains showed overall resistance to most of the antimicrobials tested (54%‒100%). Moreover, clonal-relatedness analysis using ERIC-PCR revealed seven major clones of K. pneumoniae. These findings suggest nosocomial transmission among some identical strains and emphasize the importance of strict compliance with infection prevention and control policies and regulations. Environmental reservoirs could facilitate this indirect transmission, which needs to be investigated.

Emergence of New Delhi Metallo-β-Lactamase (NDM) Genes Detected from Clinical Strains of Escherichia coli Isolated in Ouagadougou, Burkina Faso

The emergence and spread of carbapenem resistance in Gram-negative bacilli such as Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa through the production of carbapenemases is a global phenomenon. It threatens patient care and leads to therapeutic impasses. This study aims to genotypically determine the prevalence of the most frequent carbapenemase genes among multidrug-resistant E. coli strains isolated from patients at a biomedical analysis laboratory. A total of fifty-three unduplicated E. coli strains isolated from patient samples with a multidrug-resistant (MDR) profile were subjected to polymerase chain reaction (PCR) testing for carbapenem resistance genes. This study allowed us to identify fifteen strains carrying resistance genes among the fifty-three E. coli strains. All fifteen strains produced the metallo-β-lactamase enzymes; this represents a rate of 28.30% of study strains. Among these strains, ten carried the NDM resistance gene, NDM and VIM genes were detected in three strains and VIM was identified in two strains of E. coli. However, carbapenemases A (KPC and IMI), D (OXA-48), and IMP were not detected in the strains studied. Thus, NDM and VIM are the main carbapenemases detected in the strains in our study.