The occurrence of blaTEM, blaSHV and blaOXA genotypes in Extended-Spectrum β-Lactamase (ESBL)-producing Pseudomonas aeruginosa strains in Southwest of Iran

Characterization of β-lactamase and virulence genes in Pseudomonas aeruginosa isolated from clinical, environmental and poultry sources in Bangladesh

The emergence and spread of multidrug-resistant pathogens like Pseudomonas aeruginosa are major concerns for public health worldwide. This study aimed to assess the prevalence of P. aeruginosa in clinical, environmental, and poultry sources in Bangladesh, along with their antibiotic susceptibility and the profiling of β-lactamase and virulence genes using standard molecular and microbiology techniques. We collected 110 samples from five different locations, viz., BAU residential area (BAURA; n = 15), BAU Healthcare Center (BAUHCC; n = 20), BAU Veterinary Teaching Hospital (BAUVTH; n = 22), Poultry Market (PM; n = 30) and Mymensingh Medical College Hospital (MCCH; n = 23). After overnight enrichment in nutrient broth, 89 probable Pseudomonas isolates (80.90%) were screened through selective culture, gram-staining and biochemical tests. Using genus- and species-specific PCR, we confirmed 22 isolates (20.0%) as P. aeruginosa from these samples. Antibiogram profiling revealed that 100.0% P. aeruginosa isolates (n = 22) were multidrug-resistant isolates, showing resistance against Doripenem, Penicillin, Ceftazidime, Cefepime, and Imipenem. Furthermore, resistance to aztreonam was observed in 95.45% isolates. However, P. aeruginosa isolates showed a varying degree of sensitivity against Amikacin, Gentamicin, and Ciprofloxacin. The blaTEM gene was detected in 86.0% isolates, while blaCMY, blaSHV and blaOXA, were detected in 27.0%, 18.0% and 5.0% of the P. aeruginosa isolates, respectively. The algD gene was detected in 32.0% isolates, whereas lasB and exoA genes were identified in 9.0% and 5.0% P. aeruginosa isolates. However, none of the P. aeruginosa isolates harbored exoS gene. Hence, this study provides valuable and novel insights on the resistance and virulence of circulating P. aeruginosa within the clinical, environmental, and poultry environments of Bangladesh. These findings are crucial for understanding the emergence of β-lactamase resistance in P. aeruginosa, highlighting its usefulness in the treatment and control of P. aeruginosa infections in both human and animal populations.

Resistant Genes and Multidrug-Resistant Bacteria in Wastewater: A Study of Their Transfer to the Water Reservoir in the Czech Republic

Wastewater is considered the most serious source of the spread of antibiotic resistance in the environment. This work, therefore, focuses on the fate and spread of antibiotic resistance genes (ARGs) in wastewater and the monitoring of multidrug-resistant strains. ARGs were monitored in the nitrification and sedimentation tanks of the wastewater treatment plant (WWTP) and in the dam into which this WWTP flows, at various times. The highest relative abundance was found for the blaTEM > tetW > blaNDM-1 > vanA resistance genes, respectively. An increased concentration of tetracycline (up to 96.00 ng/L) and ampicillin (up to 19.00 ng/L) was found in water samples compared to other antibiotics detected. The increased incidence of seven ARGs and four antibiotics was observed in the November and December sampling times. Isolated ampicillin-resistant strains showed a high degree of resistance to ampicillin (61.2% of the total isolates had a minimum inhibitory concentration (MIC) ≥ 20 mg/mL). In 87.8% of isolates, out of the total number, the occurrence of two or more ARGs was confirmed. These multidrug-resistant strains were most often identified as Aeromonas sp. This strain could represent a significant role in the spread of multidrug resistance through wastewater in the environment.

The Bacterial Profile and Microbial Susceptibility of Acute and Chronic Dacryocystitis in Matini Hospital, Kashan, Iran

Background: Recent studies have shown an increasing incidence of antibiotic resistance in dacryocystitis. Management of diseases may include determining microbial agents and choosing appropriate antibiotics for treatment. Objectives: This study aimed to present the best treatments for dacryocystitis. To this end, specimens' microbiology and antibiotic susceptibility were examined in patients with dacryocystitis in the microbiology laboratory of the Kashan University of Medical Sciences. Methods: This cross-sectional study was performed on 172 patients presenting with acute and chronic dacryocystitis at the Matini Hospital, Kashan, between 2017 - 2018. Patient characteristics, culture isolates, and antimicrobial susceptibility data were collected. The PCR assay of the mecA gene was performed in all methicillin-resistant Staphylococcus isolates. Results: The most common bacteria were coagulase-negative staphylococci (CoNS), Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii. The majority of the isolated microbes were sensitive to rifampicin, linezolid, amikacin, and gentamicin. In Gram-negative bacilli, nine of the isolates were extended-spectrum beta-lactamase positive. The PCR test showed the frequency of mecA gene of resistant S. aureus and resistant CoNS isolates to be 40 and 46.3%, respectively. Conclusions: Coagulase-negative staphylococci were the most frequently isolated bacteria. The highest antibiotic susceptibility was observed to rifampin, linezolid, amikacin, and gentamicin. A high percentage of CoNS carried the mecA gene.