Antibiotic resistance is on the WHO’s top 10 list of global public health threats due to its rapid emergence and spread but also because of the high morbidity and mortality associated with it. Amongst the main species driving this phenomenon is A. baumannii, a member of the ESKAPE group of medical assistance-associated infections causing species famous for its extensively drug-resistant phenotypes. Our findings note a 91.52% frequency of extensively drug-resistant carbapenem-resistant A. baumannii (XDR CRAB) phenotype amongst clinical isolates from multiple hospitals in two major cities from northwestern and central Romania, harboring multiple antibiotic resistance genes such as bla_OXA-23-like in 108 (91.5%) isolates, bla_{OXA-24/40-like} in 88 (74.6%) isolates, bla_NDM in 29 (25%) isolates, ArmA in 75 (63.6%) isolates, and ant(3″)-I in 69 (58.5%) isolates and sul1 in 113 (95.76%) isolates. The isolates, although nearly identical in phenotype, displayed different genotypical profiles, with varying degrees of similarity across hospitals and cities, raising the possibility of both local outbreaks of a single clone and widespread dissemination of resistant isolates.

This study examines the prevalence and the mechanisms of antibiotic resistance in Pseudomonas aeruginosa isolates collected from healthcare units in Northwestern Transylvania, Romania, between 2022 and 2023. Given the alarming rise in antibiotic resistance, the study screened 34 isolates for resistance to 10 antibiotics, 46 ARGs, and integrase genes using PCR analysis. The results reveal a concerning increase in multidrug-resistant (MDR) and extensively drug-resistant (XDR) isolates over the two-year period. Notably, the prevalence of ARGs encoding resistance to sulfonamides and beta-lactams, particularly sul1 and bla_OXA-50, has shown a significant rise. Furthermore, the study detected the emergence of new resistance mechanisms in the same time interval. These include target protection and even more specific mechanisms, such as metallo-beta-lactamases or enzymes involved in the methylation of 23S rRNA. Statistical analysis further confirmed the correlation between Class I integrons and several ARGs, underscoring the role of horizontal gene transfer in the dissemination of resistance. These findings emphasize the urgent need for updated treatment strategies and monitoring programs to effectively combat the spread of ARGs in clinical settings.

Background: Enterococcus faecalis is a common gastrointestinal commensal and an important opportunistic pathogen. While vancomycin resistance is well characterized, data on virulence-associated genes in colonizing isolates remain limited. Methods: A total of 44 colonizing E. faecalis isolates recovered from routine VRE screening (rectal swabs) were included in the study. The presence of the virulence-associated genes asa, esp, eep, ccf, and cpd was investigated by PCR. Antimicrobial susceptibility testing was performed using standardized methods, and isolates were subsequently classified as either vancomycin-resistant (VRE) or vancomycin-susceptible (VSE). A cumulative virulence gene score was calculated for each isolate and compared between the two groups. Results: Virulence-associated genes were heterogeneously distributed. Overall, the prevalence of the investigated virulence genes was cpd (33/44), eep (26/44), esp (24/44), ccf (22/44), and asa (8/44). Among these, only esp was significantly more prevalent in VRE than in VSE isolates (p < 0.01). VRE isolates showed a significantly higher median virulence gene score compared to VSE isolates (3 [IQR: 2–4] vs. 2 [IQR: 2–3]; p = 0.028, Mann–Whitney U test). The esp gene was more frequently detected among VRE isolates, while pheromone-associated genes displayed no clear group-specific pattern. Conclusions: Colonizing E. faecalis isolates carried a heterogeneous repertoire of the selected virulence-associated genes, with a higher burden of these genes among VRE isolates. These findings contribute additional data from Eastern Europe on the molecular characteristics of colonizing E. faecalis populations and support further investigation of their epidemiological relevance in healthcare settings.

CRISPR (clustered regularly interspaced short palindromic repeats) is an immune system used by bacteria to defend themselves from different types of pathogens. It was discovered that this immune system can modify itself in specific regions called spacers due to previous interaction with foreign genetic material from phages and plasmids. Through our research, we have identified in different bacterial isolates CRISPR arrays belonging to the subtypes I-E (present in 42 samples) and I-F (present in 9 samples). The number of spacers in CRISPR arrays was also estimated based on the array length as a possible connection with the systems activity. Our results yielded arrays as small as 200 bp and as large as 1400 bp. Dobrescu et al (PDF) Article history: Received: 31 March 2022; Revised: 27 April 2022; Accepted: 9 June 2022; Available online: 30 June 2022.