Extended-Spectrum β-Lactamase (ESBL) Genotypes among Multidrug-Resistant Uropathogenic Escherichia coli Clinical Isolates from a Teaching Hospital of Nepal

Abstract

Urinary tract infections (UTI) represent the most common bacterial infections among patients visiting outpatient clinics of healthcare centers in Nepal. However, treatment of such infections is compounded by emergence and spread of multidrug-resistant uropathogens associated with extended-spectrum β-lactamases (ESBLs). In this study, we aimed to investigate the burden of antimicrobial resistance and occurrence of ESBL genes among clinical isolates of uropathogenic Escherichia coli at a tertiary care teaching hospital of Nepal. During the study period, we processed a total of 1,626 urinary tract specimens, isolated significant bacterial pathogens, and investigated their antimicrobial susceptibilities. Escherichia coli (n = 154), the predominant pathogen associated with UTI, was further investigated for the existence of ESBL enzymes by using conventional phenotypic as well as molecular approaches. Among suspected cases of UTI, we found that 15.2% were having UTI and female patients of the reproductive age group were more affected (p<0.05). Escherichia coli (154, 62.1%) was the key uropathogen, and majority (∼64.9%) of them were multidrug resistant (MDR). Among MDR E. coli isolates, 40.3% were producing extended-spectrum β-lactamases (ESBLs). bla-TEM (83.8%), bla-CTX-M (66.1%), and bla-SHV (4.8%) were common ESBL genotypes. Nitrofurantoin, gentamycin, and imipenem were the most effective antibiotics for ESBL-producing Escherichia coli isolates. It indicates that the high rates of multidrug-resistant Escherichia coli are frequent causes of UTI in our hospital. Nitrofurantoin and aminoglycosides are the most useful first-line drugs to be used in the cases of UTI. We recommend the regular investigation of drug resistance among all isolates and develop a useful antibiotic prescription policy in our country.

Detection of TEM and CTX-M Genes in Escherichia coli Isolated from Clinical Specimens at Tertiary Care Heart Hospital, Kathmandu, Nepal

“…In this study, more than one-fourth (27.3%) of the total E. coli isolates were confirmed as ESBL producers. This finding is consistent with the previous studies reported from Model Hospital, Bagbazar, Kathmandu [15], Everest Hospital, Baneshwor, Kathmandu [20], and International Friendship Hospital, Maharajgunj, Kathmandu [3], and lower than a study reported from Manmohan Memorial Medical College and Teaching Hospital (MMCTH) [16,18] and Om Hospital and Research Centre, Kathmandu [41]. The higher rate of ESBL in this organism compared to the previous studies may indicate the temporal impact of increasing infections and AMR over the years.…”

“…PCR amplification reactions were carried out in a 21 µL volume, in which a master mix containing 200 µM of dNTP s (dATP, dCTP, dGTP, and dTTP), 120 nM of each primer (forward and reverse), 0.5 U/µL of Taq polymerase in 1× PCR buffer, 25 mM of MgCl 2 , and 3 µL of DNA template was added. Amplification reactions were performed in a DNA thermal cycler under the following thermal and cycling conditions for the bla TEM (F.P:5′-GAGACAATAACCCTGGTAAAT-3′R.P:5′-AGAAGTAAGTTGGCAGCAGTG-3′) [ 16 ] and bla CTX-M (Forward Primer: 5′-TTTGCGATGTGCAGTACCAGTAA-3′, Reverse Primer: 5′-CGATATCGTTGGTGGTGCCATA-3′) [ 31 ] genes: initial denaturation at 94 °C for 1 min, denaturation at 95 °C for 5 min of 35 cycles, annealing at 55 °C for 1 min of 35 cycles for bla CTX-M and 56 °C for 45 s of 35 cycles for bla TEM , extension at 72 °C for 1 min of 35 cycles, and final extension at 72 °C for 10 min [ 16 , 31 ].…”

“…PCR amplification reactions were carried out in a 21 µL volume, in which a master mix containing 200 µM of dNTP s (dATP, dCTP, dGTP, and dTTP), 120 nM of each primer (forward and reverse), 0.5 U/µL of Taq polymerase in 1× PCR buffer, 25 mM of MgCl 2 , and 3 µL of DNA template was added. Amplification reactions were performed in a DNA thermal cycler under the following thermal and cycling conditions for the bla TEM (F.P:5 -GAGACAATAACCCTGGTAAAT-3 R.P:5 -AGAAGTAAGTTGGCAGCAGTG-3 ) [ [16,31].…”

“…Higher rates of ESBLs have been reported from Southeast Asia, including Nepal [ 14 ]. Various studies have reported the circulation of ESBL-producing bacterial strains in Nepal [ 3 , 6 , 15 , 16 , 17 , 18 ]. Laboratory facilities for culture and antimicrobial susceptibility testing in different peripheral/district hospitals are still not available in Nepal.…”

Fecal carriage of ESBL-producing <em>Escherichia coli</em> in Egyptian patients admitted to the Medical Research Institute hospital, Alexandria University

“…They are encoded by genes that are often located on transferable conjugative plasmids. Additionally, genes that confer resistance to antibacterial agents, other than beta-lactams, are frequently carried simultaneously on these plasmids and contribute to the dissemination of resistance [3] .…”