Incidence Of Resistance Genes Research Articles

Detection of Antimicrobial Susceptibility Pattern and Molecular Detection of Resistance Genes in Klebsiella pneumoniae Isolated from Urine Samples of Suspected UTI Patients Attending Public Hospitals in Nasarawa South Senatorial District, Nasarawa State, Nigeria

Aims: The aim of the current study was to determine antimicrobial susceptibility patterns and the incidence of resistance genes (β-lactamase-encoded genes) among clinical isolates of K. pneumoniae.
 Study Design: Investigative.
 Place and Duration of Study: Department of Microbiology, Nasarawa State University, Keffi, between November 2022 and July 2023.
 Methodology: A total of 375 clinical samples were randomly collected from patients and isolation and identification was done using standard microbiological methods. The antibiotic susceptibility testing for the isolates was carried out in accordance with the Clinical and Laboratory Standards Institute protocol. The detection of extended-spectrum beta-lactamase (ESBL) production in K. pneumoniae isolates was carried out using double disc synergy test. In addition, molecular detection of ESBL genes was carried out using Polymerase Chain Reaction (PCR) method.
 Results: The overall incidence rate of K. pneumoniae in the 375 clinical samples from Nasarawa South Senatorial District was 38 (10.13%). Resistance was high to ampicillin (94.74%) and amoxicillin-clavulanic acid (73.6%) but low to cefotaxime (13.16%), ceftriaxone (18.42%), ceftazidime and cefoxitin (23.60%) and gentamicin (28.94%). Most of the isolates were multi-drug resistant (MDR; 81.5%) and none was Pan Drug resistant. All 15 isolates jointly resistant to cefotaxime and/or ceftazidime and ciprofloxacin 100.0% were ESBL producers, distributed as follows: blaCTX-M-1 7(46.6%); blaCTX-M-34(26.6%); blaSHV 6(40.0%); blaTEM6 (40.0%); and blaOXA 5(33.3%).
 Conclusion: K. pneumoniae isolated from the urine of patients attending public hospitals in Nasarawa South were less resistant to cefotaxime, ceftazidime, gentamicin, ceftriaxone, and cefoxitin in the study location. This implies that the antibiotics are useful in the treatment of infection caused by K. pneumoniae. Also, ESBL-positive K. pneumoniae isolates harbored ESBL genes, with blaCTX-M as the most common.

High frequency of multidrug-resistant (MDR) Klebsiella pneumoniae harboring several \u03b2-lactamase and integron genes collected from several hospitals in the north of Iran

BackgroundKlebsiella pneumoniae is one of the leading causes of hospital outbreaks worldwide. Also, antibiotic-resistant K. pneumoniae is progressively being involved in invasive infections with high morbidity and mortality. The aim of the current study was to determine antimicrobial susceptibility patterns and the incidence of resistance genes (integron types and β-lactamase-encoded genes) among clinical isolates of K. pneumoniae.MethodsIn this cross-sectional study, a total of 100 clinical samples were obtained from hospitalized patients in three teaching hospitals in the north of Iran, from November 2018 and October 2019. Antimicrobial susceptibility testing was performed using disk agar diffusion test in line with CLSI recommendations. For colistin, minimum inhibitory concentration (MIC) was determined using broth microdilution. Based on antibiogram, multi-drug resistant (MDR) and extensive-drug resistant (XDR) strains were detected. Finally, integron types and β-lactamase resistance genes were identified using polymerase chain reaction technique.ResultsThe most and least clinical samples were related to the urine and bronchoalveolar lavage, respectively. Based on the antibiogram results, amikacin and gentamicin exhibited good activity against K. pneumoniae strains in vitro. The high resistance rate (93%) to ampicillin/sulbactam predicts the limited efficacy of this antibiotic, in the hospitals studied. Among all the 100 isolates, the frequency of MDR and XDR phenotypes were 58% and 13%, respectively, while no pan-drug resistant (PDR) strains were found. In the MDR K. pneumoniae strains, the prevalence of blaSHV, blaTEM, blaCTX-M-15, blaKPC, blaOXA-48, blaNDM β-lactamase genes were 91.4%, 82.7%, 79.3%, 29.3%, 36.2% and 6.9%, respectively, however 91.4% of the isolates were carrying intI gene. Class II and III integrons were not detected in any isolates.ConclusionThe MDR K. pneumoniae is becoming a serious problem in hospitals, with many strains developing resistance to most available antimicrobials. Our results indicate co-presence of a series of β-lactamase and integron types on the MDR strains recovered from hospitalized patients. The increasing rate of these isolates emphasizes the importance of choosing an appropriate antimicrobial regimen based on antibiotic susceptibility pattern.

Do combined nanoscale polystyrene and tetracycline impact on the incidence of resistance genes and microbial community disturbance in Enchytraeus crypticus?

It has been proved that nanoplastics can effectively adsorb pollutants and thus influence their behavior and availability. The combined toxic effects of nanoplastic and its adsorbed pollutant on the soil fauna are still not well known. We used high-throughput quantitative PCR to explore the effects of oral nanoscale polystyrene and tetracycline exposure on antibiotic resistance genes in the soil invertebrate Enchytraeus crypticus, and used bacterial 16S rRNA gene amplification sequencing to examine the response of the microbiome of E. crypticus. After 14 days of tetracycline and nanoscale polystyrene exposure, we terminated exposure and monitored the restoration of ARGs and microbiome in the E. crypticus. Results showed that the number of ARGs, especially macrolide-lincosamide-streptogramin B (MLSB), tetracycline ARGs, as well as multidrug ARGs, increased with exposure to nanoscale polystyrene and tetracycline. The abundance of Aminoglycoside and Beta_Lactamase ARGs in E. crypticus also significantly increased. The exposure significantly perturbed the abundance of families Microbacteriaceae, Streptococcaceae, Enterobacteriaceae, Rhodocyclaceae and Sphinomonadaceae. After terminating exposure for 14 days, the diversity and abundance of ARGs were not completely restored, while the microbiome was not permanently changed but reversibly impacted.