Clonal Clusters, Molecular Resistance Mechanisms and Virulence Factors of Gram-Negative Bacteria Isolated from Chronic Wounds in Ghana

Abstract

Wound infections are common medical problems in sub-Saharan Africa but data on the molecular epidemiology are rare. Within this study we assessed the clonal lineages, resistance genes and virulence factors of Gram-negative bacteria isolated from Ghanaian patients with chronic wounds. From a previous study, 49 Pseudomonas aeruginosa, 21 Klebsiella pneumoniae complex members and 12 Escherichia coli were subjected to whole genome sequencing. Sequence analysis indicated high clonal diversity with only nine P. aeruginosa clusters comprising two strains each and one E. coli cluster comprising three strains with high phylogenetic relationship suggesting nosocomial transmission. Acquired beta-lactamase genes were observed in some isolates next to a broad spectrum of additional genetic resistance determinants. Phenotypical expression of extended-spectrum beta-lactamase activity in the Enterobacterales was associated with blaCTX-M-15 genes, which are frequent in Ghana. Frequently recorded virulence genes comprised genes related to invasion and iron-uptake in E. coli, genes related to adherence, iron-uptake, secretion systems and antiphagocytosis in P. aeruginosa and genes related to adherence, biofilm formation, immune evasion, iron-uptake and secretion systems in K. pneumonia complex. In summary, the study provides a piece in the puzzle of the molecular epidemiology of Gram-negative bacteria in chronic wounds in rural Ghana.

Whole-Genome Sequencing of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli From Human Infections in Finland Revealed Isolates Belonging to Internationally Successful ST131-C1-M27 Subclade but Distinct From Non-human Sources

“…No Shiga toxin ( stx ) genes were found. Virulence factors are presented according to their pathogenicity factor groups ( Nesta et al, 2012 ; Pitout, 2012 ; Chen et al, 2016 ; Sarowska et al, 2019 ; Duan et al, 2020 ; Dekker et al, 2021 ) in Table 2 together with resistance genes other than bla .…”

Use of fluorescence imaging to optimize location of tissue sampling in hard-to-heal wounds

“…Chronic wounds have unique, polymicrobial and patient-specific microbiological profiles that cannot be inferred merely from patient’s demographics or wound type. A wound’s microbiome, bacterial virulence, and resistance genes can vary significantly between patients (depending on geographical location and comorbidities, for example) and even between wounds on the same patient ( Wolcott et al., 2016 ; Dekker et al., 2021 ). Further, the traditional concept of a single, main offending pathogen may not apply in the context of a chronic wound ( Rhoads et al., 2012 ; Rhoads et al., 2012 ).…”

Bacterial diversity significantly reduces toward the late stages among filarial lymphedema patients in the Ahanta West District of Ghana: A cross‐sectional study

“…However, there is a paucity of information on the predominance of Gram‐positive bacteria in LF wounds. The presence of pathogens such as K. pneumoniae and P. aeruginosa in wounds has been suggested not to have clinical relevance 37 …”

“…aeruginosa in wounds has been suggested not to have clinical relevance. 37 Gram-positive bacteria are the major cause of nosocomial and community-acquired infections, 38 and most antimicrobial agents target this group of bacteria. In this study, we report a trend of resistance of Gram-positive bacteria against tetracycline, chloramphenicol, and penicillin.…”