Whole-Genome Sequencing-Based Resistome Analysis of Nosocomial Multidrug-Resistant Non-Fermenting Gram-Negative Pathogens from the Balkans

Whole genome sequencing-based cataloguing of antibiotic resistant genes in piggery waste borne samples

The growing use of antibiotics in livestock is one of the main causes of the rapid global spread of antimicrobial resistance (AMR). However, extensive research on AMR in animals is currently absent. In this article, we provide the bacterial antibiotic resistance genes (ARGs) from piggery waste samples in West Bengal, India, based on whole genome sequencing (WGS). According to the study, there are alarmingly high levels of Enterobacteriaceae in piggery waste, especially slaughterhouse waste, that are resistant to beta-lactam, aminoglycoside, sulphonamide, and tetracycline. We found several plasmids carrying multidrug-resistant Enterobacteriaceae including resistant to last-resort medications like colistin and carbapenems. Our findings will serve as a guide for developing AMR management policies for livestock in India and aid in understanding the current AMR profiles of pigs. To grasp the actual situation with AMR in the pig sector, large scale sample screening must be done.

Current viewpoint on the epidemiology of nonfermenting Gram-negative bacterial strains

PURPOSE OF REVIEW

This article aims to review the epidemiology of nonfermenting Gram-negative bacilli (NFGNB) based on recent literature reports, particularly, of the less common, but with emerging clinical significance species.

RECENT FINDINGS

The reported frequency of multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa is increasing, with very significant variability, however, between different countries. Apart from the major NFGNB, that is, A. baumannii and P. aeruginosa, already recognized as of critical importance healthcare risks, several other NFGNB genera have been increasingly associated with diverse severe infections, such as Stenotrophomonas maltophilia, Burkholderia spp., Elizabethkingia spp., Chryseobacterium spp., Achromobacter spp., Alcaligenes spp., Sphingomonas spp., Shewanella spp. and Ralstonia spp., among others.

SUMMARY

The exploration of the epidemiology, as well as the pathogenic potential of the of the less frequent, but emerging and increasingly reported NFGNB, is crucial, not only for immunocompromised patients, but also for critically ill patients without overt immunosuppression. As we are heading fast towards a postantibiotic era, such information would contribute to the optimal antimicrobial management, that is, providing prompt, appropriate antimicrobial coverage when needed and, at the same time, avoiding overuse and/or inappropriate use of antimicrobial therapy. Also, it would help to better understand their transmission dynamics and to develop effective prevention strategies.

Comparative genomics analysis of Stenotrophomonas maltophilia strains from a community

Background

Stenotrophomonas maltophilia is a multidrug-resistant (MDR) opportunistic pathogen with high resistance to most clinically used antimicrobials. The dissemination of MDR S. maltophilia and difficult treatment of its infection in clinical settings are global issues.

Methods

To provide more genetic information on S. maltophilia and find a better treatment strategy, we isolated five S. maltophilia, SMYN41-SMYN45, from a Chinese community that were subjected to antibiotic susceptibility testing, biofilm formation assay, and whole-genome sequencing. Whole-genome sequences were compared with other thirty-seven S. maltophilia sequences.

Results

The five S. maltophilia strains had similar antibiotic resistance profiles and were resistant to β-lactams, aminoglycosides, and macrolides. They showed similar antimicrobial resistance (AMR) genes, including various efflux pumps, β-lactamase resistance genes (blaL1/2), aminoglycoside resistance genes [aac(6'), aph(3'/6)], and macrolide-resistant gene (MacB). Genome sequencing analysis revealed that SMYN41-SMYN45 belonged to sequence type 925 (ST925), ST926, ST926, ST31, and ST928, respectively, and three new STs were identified (ST925, ST926, and ST928).

Conclusion

This study provides genetic information by comparing genome sequences of several S. maltophilia isolates from a community of various origins, with the aim of optimizing empirical antibiotic medication and contributing to worldwide efforts to tackle antibiotic resistance.

Current Situation of Bacterial Infections and Antimicrobial Resistance Profiles in Pet Rabbits in Spain

Research on antimicrobial resistance (AMR) in pet rabbits is very scarce. The aim of this study was to provide an overview of the current state of AMR in rabbits attended to in veterinary clinics distributed in Spain. Records of 3596 microbiological results of clinical cases submitted from 2010 to 2021 were analyzed. Staphylococcus spp. (15.8%), Pseudomonas spp. (12.7%), Pasteurella spp. (10%), Bordetella spp. (9.6%) and Streptococcus spp. (6.8%) were the most frequently diagnosed agents. Enterobacteriaceae, principally Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae, accounted for about 18% of the cases and showed the highest proportion of multi-drug resistance (MDR) isolates, with 48%, 57.5% and 36% of MDR, respectively. Regarding the antimicrobial susceptibility testing for a number of antimicrobial categories/families, the largest proportion of isolates showing resistance to a median of five antimicrobial categories was observed in P. aeruginosa, Stenotrophomonas maltophilia and Burkolderia spp. In contrast, infections caused by Staphylococcus, Streptococcus spp. and Pasteurella multocida were highly sensitive to conventional antimicrobials authorized for veterinary use (categories D and C). The emergence of AMR major nosocomial opportunistic pathogens such as P. aeruginosa, S. maltophilia and K. pneumoniae in pet rabbits can represent a serious public health challenge. Consequently, collaboration between veterinarians and human health professionals is crucial in the fight against antimicrobial resistance, to optimize, rationalize and prudently use antimicrobial therapies in domestic animals and humans.