Instrumentation in Microbiology

Our newly published book for B.Sc. Microbiology Fourth-year course on Instrumentation in Microbiology MB407 of Tribhuvan University from Garuda Publication Pvt. Ltd. The whole course is divided into 8 units with illustrated figures and annexes. In addition, a collection of TU board exam questions have been included. I hope this book will be very useful for the B.Sc students and also master level students of Microbiology, TU.

This book is available at

1. Anu book (Bhotahity)

2. Bajra Barahi Book (Bhotahity)

You can also buy a soft copy of this book (Contact at upendarts@gmail.com).

Article published in The American Journal of Tropical Medicine and Hygiene

 Am. J. Trop. Med. Hyg., 105(5), 2021, pp. 1347–1355

doi:10.4269/ajtmh.21-0691

Copyright © 2021 by The American Society of Tropical Medicine and Hygiene

 

Higher Prevalence of Extended Spectrum b-Lactamase Producing Uropathogenic Escherichia coli Among Patients with Diabetes from a Tertiary Care Hospital of Kathmandu, Nepal

 

Tulsi Nayaju^1†, Milan Kumar Upreti^1†, Alina Ghimire¹, Basudha Shrestha², Basanta Maharjan², Rajesh Dhoj Joshi², Binod Lekhak³, and Upendra Thapa Shrestha^3*

 

¹Department of Microbiology, GoldenGate International College, Kathmandu, Nepal; 

²Kathmandu Model Hospital, Kathmandu, Nepal;

³Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu, Nepal

 

^*Address correspondence to Upendra Thapa Shrestha, Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu, Bagmati 44600, Nepal. E-mail:  upendra.thapashrestha@cdmi.tu.edu.np

 

^†These authors contributed equally to this work.

 

ABSTRACT

 

This study aimed to determine the occurrence of antibiotic resistance genes for b-lactamases; bla_TEM and bla_CTX-M in uropathogenic Escherichia coli isolate from urinary tract infection (UTI) suspected diabetic and nondiabetic patients. A hospital-based cross-sectional study was conducted in Kathmandu Model Hospital, Kathmandu, in association with the Department of Microbiology, GoldenGate International College, Kathmandu, Nepal, from June to December 2018. A total of 1,267 nonduplicate midstream urine specimens were obtained and processed immediately for isolation of uropathogens. The isolates were subjected to antibiotic susceptibility testing and extended-spectrum b-lactamase (ESBL) confirmation. In addition, bla_TEM and bla_CTX-M genes were detected using specific primers. The overall prevalence of UTI was 17.2% (218/1,267), of which patients with diabetes were significantly more infected; 32.3% (31/96) as compared with nonpatients with diabetes, 15.9% (187/1,171). A total of 221 bacterial isolates were obtained from 218 culture-positive specimens in which E. coli was the most predominant; 67.9% (150/221). Forty-four percent (66/150) of the total E. coli was multidrug-resistant and 37.3% (56/150) were ESBL producers. Among 56 isolates, 92.3% (12/13) were from patients with diabetes, and 83.0% (44/53) were from nondiabetics. Furthermore, 84.9% of the screened ESBL producers were confirmed to possess either single or both of bla_TEM and bla_CTX-M genes. The bla_TEM and bla_CTX-M genes were detected in 53.6% and 87.5% of the phenotypically ESBL confirmed E. coli, respectively. Higher rates of ESBL producing uropathogenic E. coli are associated among patients with diabetes causing an alarming situation for disease management. However, second-line drugs with broad antimicrobial properties are still found to be effective drugs for multidrug-resistant strains.

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Article published in Diseases, MDPI

 

MDPI

Diseases 2021, 9, 80. https://doi.org/10.3390/diseases9040080

 

Antibiotic Susceptibility, Biofilm Production, and Detection of mecA Gene among Staphylococcus aureus Isolates from Different Clinical Specimens

Upama Gaire¹, Upendra Thapa Shrestha¹, Sanjib Adhikari¹, Nabaraj Adhikari¹, Anup Bastola², Komal Raj Rijal^1,*, Prakash Ghimire¹ and Megha Raj Banjara^1,*

¹Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu 44600, Nepal

²Sukraraj Tropical and Infectious Diseases Hospital, Teku, Kathmandu 44600, Nepal; docanup11@gmail.com

 

* Correspondence: komal.rijal@cdmi.tu.edu.np (K.R.R.); megha.banjara@cdmi.tu.edu.np (M.R.B.)

 

ABSTRACT

 The increasing incidence of methicillin-resistant and biofilm-forming S. aureus isolates in hospital settings is a gruesome concern today. The main objectives of this study were to determine the burden of S. aureus in clinical samples, assess their antibiotic susceptibility pattern and detect biofilm formation and mecA gene in them. A total of 1968 different clinical specimens were processed to isolate S. aureus following standard microbiological procedures. Antibiotic susceptibility test of the isolates was performed by Kirby–Bauer disc-diffusion method following CLSI guidelines. Biofilm was detected through tissue culture plate method. Methicillin-resistant S. aureus (MRSA) isolates were screened using cefoxitin (30 μg) discs and mecA gene was amplified by conventional polymerase chain reaction (PCR). Of 177 bacterial growth, the prevalence of S. aureus was 15.3% (n= 27). MRSA were 55.6% (15/27) and 44% (12/27) exhibited multidrug resistance (MDR). There was no significant association between methicillin resistance and MDR (p > 0.05). Both MRSA and MSSA were least sensitive to penicillin (100%, 75%) followed by erythromycin (86.6%, 66.6%). Most of the MRSA (93.4%) were susceptible to tetracycline. All S. aureus isolates were biofilm producers—19 (70%) were weak and only one (4%) was a strong biofilm producer. The strong biofilm-producing MSSA was resistant to most of the antibiotics except cefoxitin and clindamycin. None of the MSSA possessed mecA gene while 8 (53.3%) MRSA had it. More than half of S. aureus isolated were MRSA. High incidence of multidrug resistance along with capacity to form biofilm among clinical isolates of S. aureus is a matter of apprehension and prompt adoption of biosafety measures is suggested to curb their dissemination in the hospital environments.

 

Keywords: S. aureus; antibiotic susceptibility; MRSA; mecA gene; biofilm

 

Citation: Gaire, U.; Shrestha, U.T.; Adhikari, S.; Adhikari, N.; Bastola, A.; Rijal, K.R.; Ghimire, P.; Banjara, M.R. Antibiotic Susceptibility, Biofilm Production and Detection of mecA Gene among Staphylococcus aureus Isolates from Different Clinical Specimens. Diseases 2021, 9, 80. https://doi.org/10.3390/diseases9040080

 

Academic Editor: St Patrick Reid

Received: 9 October 2021

Accepted: 29 October 2021

Published: 1 November 2021

 

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