Background: ESBL problem is increasing worldwide and only limited studies on genes of ESBL are performed in Nepal. Objectives: We aimed to focus on the molecular detection of plasmid-mediated blaTEM, blaSHV and blaCTX-M genes among the ESBL producing Enterobacteriaceae from different clinical samples. Methods: A total of 550 clinical samples were processed and organisms of Enterobacteriaceae were identified using standard microbiological process. ESBL producers were screened and confirmed using modified Kirby Bauer disc diffusion method by CLSI guidelines. Plasmids extracted from the confirmed ESBL positives were the template for PCR. blaSHV, blaTEM and blaCTX-M genes were amplified using specific primers of respective genes by uniplex PCR. The presence of these genes was confirmed by gel electrophoresis. Results: Among 550 different clinical samples 343 (62.36%) were culture positive. Of which, 157 (45.57%) belonged to Enterobacteriaceae. Escherichia coli (45.9%) was predominant. Of these 33.2% (52/157) isolates ESBL positive. ESBL- E. coli (52.8%) were prevalent. All ESBL positive organisms were sensitive to imipenem. Of confirmed ESBL positives, 34.6% harboring blaTEM gene, 30.8% harboring blaSHV gene and blaCTX-M genes were present in all ESBL producers. Twenty-eightout of 52 (53.9%) isolates harbored multiple bla genes, the most common combination being blaCTX-M + blaTEM (21.2%). Conclusion: We report 100% plasmid mediated CTX-M genotype among ESBL producers which might indicate rapid dissemination of blaCTX-Mgenes from the community to the patients. Besides, there is a need for regular monitoring of antibiotic resistance in the country and de-escalate the use of antibiotics so as to preserve the antibiotics for future generation.

Objectives: This study was done to determine the drug resistance pattern and Extended Spectrum β-Lactamase (ESBL) in bacterial isolates of Enterobacteriaceae family from different clinical specimens.Methods: The isolates were identified by conventional culture techniques and subjected to antimicrobial susceptibility testing by modified Kirby Bauer disk diffusion methods and ESBL detection by combined disk method.Results: Of the total 1602 sample processed 200 (12.5%) bacteria of Enterobacteriaceae family were isolated and 85.5% of them were multidrug resistant. Of the total Enterobacteriaceae isolates 27% were ESBL producers. Single isolate of stool was MDR and ESBL producer. Higher prevalence of MDR isolates (100%) and ESBL producer (41.2%) was observed in sputum specimen. Higher multidrug resistance (92.1%) and ESBL production (35%) was detected in Klebsiella pneumoniae.Conclusion: The most effective antibiotics towards the isolates of Enterobacteriaceae were imipenem, amikacin, chloramphenicol and tetracycline. Emergence of MDR and ESBL producing Enterobacteriaceae requires proper infection control measures and routine and reliable detection of ESBL with rationale use of antibiotics.

Staphylococcus aureus (S. aureus) is an important pathogen affecting children worldwide. Children are at increased risk of nasal colonization and may be responsible for spreading S. aureus and methicillin-resistant S. aureus (MRSA) to the community settings. This study aimed to determine MRSA nasal colonization among school-going (aged 10–16 years) children of Kathmandu Valley and detect the mecA gene among isolated S. aureus. This study is the first study from Nepal to test the mecA gene from S. aureus from the community (school children). A total of 190 samples were collected from anterior nares, and S. aureus was identified using standard microbiological techniques. An antibiotic susceptibility test was performed, and MRSA screening was done by incorporating the cefoxitin disk in the AST plate. DNA was extracted using the hexadecyltrimethylammonium bromide (CTAB) method, and the mecA gene was detected using PCR. Statistical analysis was carried out using SPSS v16.0. Among the total of 190 children, 85 (44.7%) had nasal S. aureus colonization, and 45 (53%) were positive for MRSA. The highest MRSA colonization (100%) was found in females aged 10–12 years. Age and handshaking habits were associated risk factors of nasal MRSA colonization. Gentamycin, linezolid, and vancomycin were highly effective against MRSA, and erythromycin was the least effective besides cefoxitin and penicillin. Similarly, among 45 MRSA isolates, 41 (91.1%) were mecA gene-positive, and among 40 MSSA isolates, 38 (95%) were mecA gene positive. Our study showed a high prevalence of MRSA among school children. The prevalence of the mecA gene among MRSA isolates was also high. Therefore, the proper screening of MRSA should be done to identify, decolonize carriers and prevent the possible spread of MRSA to students in school and even to the community.