scholarly journals Genomic Identification of Multidrug-Resistant Salmonella Virchow Monophasic Variant Causing Human Septic Arthritis

Pathogens ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 536
Author(s):  
Zhenyu Wang ◽  
Haiyan Xu ◽  
Chao Chu ◽  
Yuanyue Tang ◽  
Qiuchun Li ◽  
...  

The monophasic variant of Salmonella Typhimurium has emerged and increased rapidly worldwide during the past two decades. The loss of genes encoding the second-phase flagella and the acquirement of the multi-drug resistance cassette are the main genomic characteristics of the S. Typhimurium monophasic variant. In this study, two Salmonella strains were isolated from the knee effusion and feces of a 4-year-old girl who presented with a case of septic arthritis and fever, respectively. Primary serovar identification did not detect the second-phase flagellar antigens of the strains using the classical slide agglutination test. Whole-genome sequencing analysis was performed to reveal that the replacement of the fljAB operon by a 4.8-kb cassette from E. coli caused the non-expression of phase-2 flagellar antigens of the strains, which were confirmed to be a novel S. Virchow monophasic variant (Salmonella 6,7,14:r:-) by core-genome multi-locus sequence typing (cgMLST). Compared to the 16 published S. Virchow genomes, the two strains shared a unique CRISPR type of VCT12, and showed a close genetic relationship to S. Virchow BCW_2814 and BCW_2815 strains, isolated from Denmark and China, respectively, based on cgMLST and CRISPR typing. Additionally, the acquisition of Salmonella genomic island 2 (SGI2) with an antimicrobial resistance gene cassette enabled the strains to be multidrug-resistant to chloramphenicol, tetracycline, trimethoprim, and sulfamethoxazole. The emergence of the multidrug-resistant S. Virchow monophasic variant revealed that whole-genome sequencing and CRISPR typing could be applied to identify the serovaraints of Salmonella enterica strains in the national Salmonella surveillance system.


2020 ◽  
Vol 69 (7) ◽  
pp. 1013-1019
Author(s):  
Tryna Tania ◽  
Pratiwi Sudarmono ◽  
R. Lia Kusumawati ◽  
Andriansjah Rukmana ◽  
Wahyu Agung Pratama ◽  
...  

Introduction. Multidrug-resistant tuberculosis (MDR-TB) is a major public health problem globally, including in Indonesia. Whole-genome sequencing (WGS) analysis has rarely been used for the study of TB and MDR-TB in Indonesia. Aim. We evaluated the use of WGS for drug-susceptibility testing (DST) and to investigate the population structure of drug-resistant Mycobacterium tuberculosis in Java, Indonesia. Methodology. Thirty suspected MDR-TB isolates were subjected to MGIT 960 system (MGIT)-based DST and to WGS. Phylogenetic analysis was done using the WGS data. Results obtained using MGIT-based DST and WGS-based DST were compared. Results. Agreement between WGS and MGIT was 93.33 % for rifampicin, 83.33 % for isoniazid and 76.67 % for streptomycin but only 63.33 % for ethambutol. Moderate WGS–MGIT agreement was found for second-line drugs including amikacin, kanamycin and fluoroquinolone (73.33–76.67 %). MDR-TB was more common in isolates of the East Asian Lineage (63.3%). No evidence of clonal transmission of DR-TB was found among members of the tested population. Conclusion. Our study demonstrated the applicability of WGS for DST and molecular epidemiology of DR-TB in Java, Indonesia. We found no transmission of DR-TB in Indonesia.



2019 ◽  
Vol 63 (5) ◽  
Author(s):  
Satoshi Nakano ◽  
Takao Fujisawa ◽  
Yutaka Ito ◽  
Bin Chang ◽  
Yasufumi Matsumura ◽  
...  

ABSTRACT Since the introduction of pneumococcal conjugate vaccines (PCVs), an increase in the incidence of disease attributable to serotype 15A-ST63 (sequence type 63) pneumococci has been observed in many regions worldwide. We conducted a nationwide pediatric pneumococcal infection surveillance study between 2012 and 2014 in Japan. In the surveillance study, we detected multidrug-resistant serotype 15A-CC63 (clonal complex 63) strains (resistant to macrolides, penicillin, cefotaxime, and meropenem); in this study, we analyzed these resistant isolates to determine the dynamics and mechanism of resistance using whole-genome sequencing. In most of the penicillin-, cefotaxime-, and meropenem-resistant strains, recombination occurred in the pbp2x region, resulting in the acquisition of cefotaxime resistance in addition to penicillin and meropenem resistance. In the multidrug-resistant serotype 15A-CC63 strains, we identified a specific clone with ST9084, and all of the isolates were recovered from the Yamaguchi prefecture in Japan. All of the serotype 15A-ST9084 isolates had a novel pbp2x type (pbp2x-JP3) that was inserted by recombination events. The conserved amino acid motif profiles of pbp1a, pbp2b, and pbp2x of the strains were identical to those of serotype 19A-ST320. A Bayesian analysis-based date estimation suggested that this clone emerged in approximately 2002 before the introduction of the PCV in Japan. This clone should be monitored because serotype 15A is not contained in the currently used 13-valent PCV (PCV13), and it was resistant to beta-lactams, which are often used in a clinical setting.







2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kathy E. Raven ◽  
Sophia T. Girgis ◽  
Asha Akram ◽  
Beth Blane ◽  
Danielle Leek ◽  
...  

AbstractWhole-genome sequencing is likely to become increasingly used by local clinical microbiology laboratories, where sequencing volume is low compared with national reference laboratories. Here, we describe a universal protocol for simultaneous DNA extraction and sequencing of numerous different bacterial species, allowing mixed species sequence runs to meet variable laboratory demand. We assembled test panels representing 20 clinically relevant bacterial species. The DNA extraction process used the QIAamp mini DNA kit, to which different combinations of reagents were added. Thereafter, a common protocol was used for library preparation and sequencing. The addition of lysostaphin, lysozyme or buffer ATL (a tissue lysis buffer) alone did not produce sufficient DNA for library preparation across the species tested. By contrast, lysozyme plus lysostaphin produced sufficient DNA across all 20 species. DNA from 15 of 20 species could be extracted from a 24-h culture plate, while the remainder required 48–72 h. The process demonstrated 100% reproducibility. Sequencing of the resulting DNA was used to recapitulate previous findings for species, outbreak detection, antimicrobial resistance gene detection and capsular type. This single protocol for simultaneous processing and sequencing of multiple bacterial species supports low volume and rapid turnaround time by local clinical microbiology laboratories.



Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 196
Author(s):  
Beverly Egyir ◽  
Jeannette Bentum ◽  
Naiki Attram ◽  
Anne Fox ◽  
Noah Obeng-Nkrumah ◽  
...  

Staphylococcus aureus (S. aureus) is a common cause of surgical site infections (SSIs) globally. Data on the occurrence of methicillin-susceptible S. aureus (MSSA) as well as methicillin-resistant S. aureus (MRSA) among patients with surgical site infections (SSIs) in sub-Saharan African are scarce. We characterized S. aureus from SSIs in Ghana using molecular methods and antimicrobial susceptibility testing (AST). Wound swabs or aspirate samples were collected from subjects with SSIs. S. aureus was identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF-MS); AST was performed by Kirby-Bauer disk diffusion, and results were interpreted according to the Clinical and Laboratory Standards Institute (CLSI) guideline. Detection of spa, mecA, and pvl genes was performed by polymerase chain reaction (PCR). Whole-genome sequencing (WGS) was done using the Illumina MiSeq platform. Samples were collected from 112 subjects, with 13 S. aureus isolates recovered. Of these, 92% were sensitive to co-trimoxazole, 77% to clindamycin, and 54% to erythromycin. Multi-drug resistance was detected in 5 (38%) isolates. The four mecA gene-positive MRSA isolates detected belonged to ST152 (n = 3) and ST5 (n = 1). In total, 62% of the isolates were positive for the Panton-Valentine leukocidin (pvl) toxin gene. This study reports, for the first time, a pvl-positive ST152-t355 MRSA clone from SSIs in Ghana. The occurrence of multi-drug-resistant S. aureus epidemic clones suggests that continuous surveillance is required to monitor the spread and resistance trends of S. aureus in hospital settings in the country.





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