No abstract

Background and Objectives: Pseudomonas aeruginosa is one of the leading causes of hospital acquired infections. Increased resistance in this organism continues to pose a significant threat to patient care because of limited therapeutic options. The main objective of this study was to find out the prevalence and current antimicrobial susceptibility pattern of P. aeruginosa isolates obtained from various clinical samples at a tertiary care hospital. Material and Methods: The study was conducted in a tertiary care hospital in Bharatpur, Chitwan, Nepal on 453 isolates of Pseudomonas aeruginosa from various clinical samples. The colonies which were grown on culture media were identified by different standard biochemical tests. Antimicrobial susceptibility testing was done using Kirby–Bauer disc diffusion method and the results were interpreted according to the CLSI guidelines. Quality control of the test was done by standards ATCC strain of P. aeruginosa 27853. Results: This present study revealed the prevalence rate of P. aeruginosa was 11.29%. Piperacillintazobactam was the most sensitive chemotherapeutic agent with 94.26% susceptibility rate, followed by imipenem 89.40% and levofloxacin 88.08%. Amikacin showed better susceptibility rate 67.33% than that of gentamicin 48.78%; the susceptibility rate to cephalosporin and aztreonam was relative very low. Most of the P. aeruginosa strains were isolated from clinical samples like sputum 206, urine 81, respiratory secretion 76, and pus 35. Out of 453 clinical isolates, 167(36.86%) clinical isolates of P. aeruginosa were found to be MDR. Conclusion: Most of the P. aeruginosa strains were isolates from sputum, urine, respiratory secretions and pus samples and were found to be MDR. Piperacillin-tazobactam was the most sensitive chemotherapeutic agent followed by Imipenem, levofloxacin.

Background: Urinary tract infection (UTI) is one of the major health problems in Nepal. Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) are two important bacteria associated with UTI. This study was designed to assess the prevalence of extended spectrum beta-lactamase (ESBL) producing E. coli and K. pneumoniae in urinary isolates at College of Medical Sciences and Teaching Hospital, Bharatpur, Chitwan, Nepal. Methods: We aseptically received 5564 mid-stream urine samples of suspected UTI patients from September 2016 to August 2018. The randomly collected 5564 urine samples were processed by standard Microbiological guidelines as recommended by Clinical and Laboratory Standards Institute (CLSI). All isolates including E. coli and K. pneumoniae were identified using the specific biochemical and sugar fermentation tests. Antibiotic sensitivity test was performed for all the isolates against all commonly used antibiotics by modified Kirby-Bauer disk diffusion method and interpreted following CLSI guidelines. First performed initial screening method then confirmed for ESBL production by phenotypic confirmatory disc diffusion test (PCDDT). Results: Out of 5,564 urine specimens investigated, E. coli was isolated in 1219 (63.99%) and K. pneumoniae in 223 (11.70%) cases. Initial screening revealed 615 (50.45%) isolates of E. coli and 127 (56.95%) K. pneumoniae to be resistant. Further testing by PCDDT method confirmed 102 (16.58%) E. coli and 25 (19.68%) K. pneumoniae isolates to be ESBL producers. These ESBL producers’ uropathogens revealed high degree of resistance to cephalosporins (100%) and quinolones (52%-92%) group of antibiotics. Conclusions: In our study the prevalence of ESBL producing K. pneumoniae was found to be 19.68%, those of E. coli was to be 16.58% by PCDDT. In this study, all ESBL producing K. pneumoniae isolates were sensitive (100%) to meropenem and E. coli showed 98.04% sensitive to meropenem. Hence, for the treatment of these ESBL infections, currently, carbapenems are the recommended drug of choice.