BackgroundUrinary Tract Infection (UTI) is one of the most common infectious diseases and people of all age-groups and geographical locations are affected. The impact of disease is even worst in low-resource developing countries due to unaware of the UTIs caused by multidrug-resistant (MDR) pathogens and the possibility of transfer of MDR traits between them. The present study aimed to determine the prevalence of MDR bacterial isolates from UTI patients, the antibiotic resistance pattern and the conjugational transfer of multidrug resistance phenotypes in Escherichia coli (E. coli).ResultsTwo hundred and nineteen bacterial isolates were recovered from 710 urine samples at Kathmandu Model hospital during the study period. All samples and isolates were investigated by standard laboratory procedures. Among the significant bacterial growth (30.8%, 219 isolates), 41.1% isolates were MDR. The most prevailing organism, E. coli (81.3%, 178 isolates) was 38.2% MDR, whereas second most common organism, Citrobacter spp. (5%, 11 isolates) was found 72.7% MDR. Extended-spectrum β-lactamase (ESBL) production was detected in 55.2% of a subset of MDR E. coli isolates. Among the 29 MDR E. coli isolates, plasmids of size ranging 2-51 kb were obtained with different 15 profiles. The most common plasmid of size 32 kb was detected in all of the plasmid-harbored E. coli strains. The majority of E. coli isolates investigated for the multidrug resistance transfer were able to transfer plasmid-mediated MDR phenotypes along with ESBL pattern with a frequency ranging from 0.3 × 10-7 to 1.5 × 10-7 to an E. coli HB101 recipient strain by conjugation. Most of the donor and recipient strain showed high levels of minimum inhibitory concentration (MIC) values for commonly-used antibiotics.ConclusionsThe high prevalence of multidrug resistance in bacterial uropathogens was observed. Particularly, resistance patterns were alarmingly higher for amoxycillin, co-trimoxazole, flouroquinolones and third-generation cephalosporins, which necessitate the re-evaluation of first and second line therapies for UTI. In addition, conjugational co-transfer of MDR phenotypes with ESBL-positive phenotypes was observed in MDR E. coli.

The worldwide increase of multidrug resistance in both community- and health-care associated bacterial infections has impaired the current antimicrobial therapy, warranting the search for other alternatives. We aimed to find the in vitro antibacterial activity of ethanolic extracts of 16 different traditionally used medicinal plants of Nepal against 13 clinical and 2 reference bacterial species using microbroth dilution method. The evaluated plants species were found to exert a range of in vitro growth inhibitory action against the tested bacterial species, and Cynodon dactylon was found to exhibit moderate inhibitory action against 13 bacterial species including methicillin-resistant Staphylococcus aureus, imipenem-resistant Pseudomonas aeruginosa, multidrug-resistant Salmonella typhi, and S. typhimurium. The minimum inhibitory concentration (MIC) values of tested ethanolic extracts were found from 31 to >25,000 μg/mL. Notably, ethanolic extracts of Cinnamomum camphora, Curculigo orchioides, and Curcuma longa exhibited the highest antibacterial activity against S. pyogenes with a MIC of 49, 49, and 195 μg/mL, respectively; whereas chloroform fraction of Cynodon dactylon exhibited best antibacterial activity against S. aureus with a MIC of 31 μg/mL. Among all, C. dactylon, C. camphora, C. orchioides, and C. longa plant extracts displayed a potential antibacterial activity of MIC < 100 μg/mL.

Limited information is available regarding AmpC β-lactamase (ABL)-producing Enterobacteriaceae compared to extended-spectrum β-lactamase-producing enterobacteria. Since ABL-producing organisms are often resistant to multiple antimicrobial agents, therapeutic options against these pathogens are limited. Among 230 clinical Enterobacteriaceae isolates, 64 (27.8%) were found to produce ABL in our study. Escherichia coli (83.9%) was a predominant pathogen, followed by Citrobacter freundii (5.2%). A significant proportion of ABL-producing isolates (81.3%) were found to be multidrug resistant against commonly used antibiotics. Univariate analysis showed that prior history of taking antibiotics (odds ratio [OR], 5.278; confidence interval [CI], 2.838-9.817; p<0.001) and being inpatients (OR, 4.587; CI, 2.132-9.9; p<0.001) were associated with ABL positivity. Regular antimicrobial resistance surveillance for ABL-producing Enterobacteriaceae is warranted for proper antimicrobial treatment strategy and policy making due to ABL-positive infections.