Search

Diarrheagenic Escherichia coli (DEC), an important agent of infectious diarrhea, is constantly evolving, making its periodic monitoring necessary. However, the DEC genotypes in Ghana remain uncharacterized. We focused on characterizing the molecular serotypes, virulence factors, multilocus sequence types, and the phylogenetic relatedness among different DEC pathotypes recovered from stool samples of pediatric patients with symptoms of diarrhea from the Western region of Ghana. We detected all five common DEC pathotypes, with the majority of the isolates being enterotoxigenic E. coli (ETEC) harboring the heat-labile enterotoxin gene. The DEC strains exhibited diverse serotypic identity with novel and previously reported outbreak strains. Sequence types (ST) ST38, ST316, and ST1722 were most prevalent, and clonal complex 10 (CC10) was the most common CC. A close evolutionary distance was observed among most of the isolates. Coli surface antigen 6 was the most prevalent (44%, n = 11) ETEC-specific colonization factor. Nearly all the isolates harbored lpfA, and the frequencies of other virulence genes such as pap and cnf1 were 7.9% and 18.4%, respectively. This study provides insights into the important and novel genotypes circulating in the Western region of Ghana that should be monitored for public health.

The emergence and spread of carbapenemase-producing bacteria are serious threats to public health. We characterized two OXA-181-producing Escherichia coli isolates from pediatric patients with diar...

Extra-intestinal pathogenic Escherichia coli (ExPEC) is one of the world’s leading causes of bloodstream infections with high mortality. Sequence type 410 (ST410) is an emerging ExPEC clone resistant to a wide range of antibiotics. In this study, we investigated the epidemiology of 21 ST410 E. coli isolates from two Ghanaian hospitals. We also investigated the isolates within a global context to provide further insight into the dissemination of this highly pathogenic clone. A phylogenetic tree of the 21 isolate genomes, along with 102 others from global collection, was constructed representing the ensuing clades and sub-clades of the ST: A/H53, B2/H24R, B3/H24Rx, and B4/H24RxC. The carbapenem-resistant sub-clade B4/H24RxC is reported to have emerged in the early 2000s when ST410 acquired an IncX3 plasmid carrying a blaOXA–181 carbapenemase gene, and a second carbapenemase gene, blaNDM–5, on a conserved IncFII plasmid in 2014. We identified, in this study, one blaOXA–181–carrying isolate belonging to B4/H24RxC sub-lineage and one carrying blaNDM–1 belonging to sub-lineage B3/H24Rx. The blaOXA–181 gene was found on a 51kb IncX3 plasmid; pEc1079_3. The majority (12/21) of our Ghanaian isolates were clustered with international strains described by previous authors as closely related strains to B4/H24RxC. Six others were clustered among the ESBL-associated sub-lineage B3/H24Rx and three with the globally disseminated sub-lineage B4/H24RxC. The results show that this highly pathogenic clone is disseminated in Ghana and, given its ability to transmit between hosts, it poses a serious threat and should be monitored closely.

Background: The genus Roseomonas, containing pink-pigmented glucose nonfermentative bacteria, has been associated with various primary and nosocomial human infections; however, to our knowledge, its nosocomial transmission has never been reported in the literature. Here, we report a nosocomial cluster of Roseomonas mucosa bacteremia. Methods: Two cases of R. mucosa bacteremia in 2018 are described. Clinical and epidemiological investigations were undertaken. Environmental surfaces prone to water contamination in the patient wards were sampled and cultured. The sampled surfaces included sinks, faucets, toilets, sewage, showerheads, refrigerators, exhaust vents, and washing machines. The 2 clinical isolates and all environmental isolates that showed growth of pink colonies were identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry and 16S rRNA gene sequencing. Pulse-field gel electrophoresis (PFGE) was performed and fingerprinting software was used to analyze the DNA restriction patterns and determine their similarity. Results: Two patients who developed R. mucosa bacteremia had received care from the same treatment team. The patients were on different wards but had overlapping hospital stays. In addition to the treatment team, no other shared exposure was identified. Moreover, 126 environmental surfaces were sampled, of which 7 samples grew pink colonies. The 9 isolates from the patients and the environmental samples were examined using 16S rRNA gene sequencing. Overall, 7 isolates, including isolates from both patients, were identified as R. mucosa, and the other 2 isolates were identified as Roseomonas gilardii subsp. rosea (Fig. 1). With 80% similarity as a cutoff, PFGE analysis revealed that the R. mucosa isolates from 2 patients’ blood cultures and 3 environmental isolates (a washing machine in the ward, a sink in the shared washroom, and a sink in the patient room) belonged to the same clone (Fig. 2). Conclusions: The hospital water environment was contaminated with R. mucosa, and the same clone caused bacteremia in 2 separate patients, suggesting nosocomial transmission of R. mucosa possibly linked to contaminated water, environment, and/or patient care.Funding: NoneDisclosures: None

Background Clostridioides difficile ribotype (RT) 019/sequence type (ST) 67 strains belong to a hypervirulent lineage closely related to RT027/ST1; however, limited data are available for hypervirulent clade 2 lineages in Japan. Herein, we report the draft genome of a C. difficile strain B18-123 belonging to clade 2, RT019/ST67 for the first time in Japan. Results The pathogenicity locus carried by B18-123 (19.6 kb) showed higher homology (97.29% nucleotide identity) with strain R20291 (RT027/ST1) than the reference strain 630 (RT012/ST54), and B18-123 harbored 8-nucleotide substitutions in tcdC. However, it did not contain an 18-base pair (bp) deletion or a single-bp deletion at position 117 in tcdC, which was identified in the previous strain R20291. A cytotoxicity assay revealed similar cytotoxicity levels between strains B18-123 and ATCC BAA-1870 (RT027/ST1). The B18-123 strain was found to be susceptible to metronidazole and vancomycin. Conclusion Our findings contribute to the further understanding of the characteristics of hypervirulent clade 2 including RT019/ST67 lineages.

Objectives The emergence and spread of carbapenemase-producing Enterobacteriaceae is a worldwide concern. This study reports the whole genome sequence of an NDM-5-, CTX-M-14-, OXA-10- and MCR-1-co-producing Escherichia coli sequence type 167 (ST167) multidrug-resistant clinical strain (EC129) isolated from a sputum sample of a hospitalised patient diagnosed with pneumonia. Methods The genome of E. coli EC129 was subjected to next-generation sequencing and reads were assembled. The draft genome was annotated using DDBJ Read Annotation Pipeline DFAST server, followed by subsequent in silico analysis. Results The genome of E. coli ST167 strain EC129 is 5 319 159 bp in length and contains 5022 protein-coding sequences. The blaNDM-5, blaCTX-M-14, blaOXA-10 and mcr-1 genes were detected along with other antimicrobial resistance genes conferring resistance to aminoglycosides, fluoroquinolones, sulfonamides, trimethoprim and tetracyclines. Antimicrobial susceptibility testing revealed that the isolate was resistant to all antimicrobial agents except colistin. Conclusion To our knowledge, this study is the first to report anE. coli ST167 strain co-producing NDM-5, CTX-M-14, OXA-10 and MCR-1 isolated from a sputum sample of an individual with pneumonia in Japan, thus elucidating the molecular characteristics and resistance gene diversity of this strain.

Global dissemination of New Delhi metallo-β-lactamase (NDM)-producing bacteria has become a major health threat. However, there are few reports regarding the identification and characterisation of NDM-producing bacteria from West Africa, including Ghana. An Escherichia coli strain with resistance to meropenem was isolated from the Tamale Teaching Hospital in Ghana. Its identification and determination of antibiotic susceptibility profile were carried out using commercial systems. The antibiotic resistance mechanism was analysed by phenotypic detection kits, PCR, and DNA sequencing. Conjugation experiments, S1 nuclease pulsed field gel electrophoresis, and Southern blotting were performed. Finally, the NDM-1-harbouring plasmid was characterised using next-generation sequencing and phylogenetic analysis. The meropenem-resistant Escherichia coli strain EC2189 harboured blaNDM-1 and belonged to sequence type 410. blaNDM-1 was located on the IncHI type transferrable plasmid p2189-NDM (248,807 bp long), which co-carried multiple resistance genes, such as blaCTX-M-15, aadA1, aac(6')-Ib, sul3, dfrA12, and cmlA1. p2189-NDM phylogenetically differed from previously identified blaNDM-1-positive IncHI type plasmids. A truncated Tn125 containing blaNDM-1 was bracketed by an ISSm-1-like insertion sequence upstream and by a site-specific integrase downstream. To the best of our knowledge, we have, for the first time identified and molecularly characterised an NDM-1-producing Enterobacteriaceae strain in Ghana with blaNDM-1 that had a novel genetic structure. Our findings indicate a possibility of NDM-1 dissemination in Ghana and underscore the need for constant monitoring of carbapenemase-producing bacteria.

Purpose Bile acids play an important role in Clostridioides difficile life cycle. Deoxycholate (DCA), one of the most abundant secondary bile acids, is known to inhibit vegetative growth and toxin production. However, limited data are available on the role of DCA on C. difficile sporulation. Here, we investigated the phenotypic and genotypic impact of DCA on the growth, toxin production, and sporulation of C. difficile. Methodology Four genetically divergent C. difficile strains were cultured in nutrient-rich broth with and without DCA at various concentrations, and growth activity was evaluated for each strain. Cytotoxicity assays using culture supernatants from cells grown in nutrient-rich broth with and without 0.01% DCA were conducted. Sporulation efficiency was determined using sporulation media with and without 0.01% DCA. Transcript levels of tcdB and spo0A were analyzed using quantitative reverse-transcription polymerase chain reaction. Results We found that DCA led to growth reduction in a dose-depended manner and regulated toxin production by repressing tcdB expression during vegetative growth. To our knowledge, we have also provided the first evidence that DCA reduces C. difficile sporulation efficiency through the downregulation of spo0A expression during the sporulation stage. Conclusions DCA modulates C. difficile sporulation, vegetative growth, and toxin production., Microbiology; Hepatobiliary System; Infectious Disease; Medical Microbiology; Microbiology Epidemiology; Bacteriology; deoxycholate; Clostridioides difficile; sporulation; toxin production; vegetative growth.