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Updated: May 13, 2026

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Emerging threat of multidrug resistant bugs--Acinetobacter calcoaceticus baumannii complex and methicillin resistant

Shyam Kumar Mishra1, Basista Prasad Rijal, Bharat Mani Pokhrel

  • 1Department of Microbiology, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal. smishra7@hotmail.com

BMC Research Notes
|March 19, 2013
PubMed
Abstract

Insights

Multidrug-resistant (MDR) Acinetobacter and methicillin-resistant Staphylococcus aureus (MRSA) are prevalent in Nepal. High rates of MDR and extended-spectrum beta-lactamase (ESBL) producing Acinetobacter, alongside significant MRSA, highlight the urgent need for antimicrobial stewardship.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Clinical Diagnostics

Background:

  • Multidrug-resistant (MDR) Acinetobacter spp. and methicillin-resistant Staphylococcus aureus (MRSA) infections pose a global health threat.
  • Understanding the prevalence of these resistant strains is critical for reducing associated morbidity and mortality.

Purpose of the Study:

  • To determine the prevalence and characteristics of MDR Acinetobacter spp. and MRSA in a tertiary care setting in Nepal.
  • To identify extended-spectrum beta-lactamase (ESBL) production in Acinetobacter isolates.

Main Methods:

  • Specimens (sputum, endotracheal aspirate, bronchial washing) were collected from patients with suspected lower respiratory tract infections.
  • Standard microbiological methods were used for bacterial isolation and identification.
  • Double disk synergy test for ESBL detection in Acinetobacter and cefoxitin/oxacillin disk diffusion for MRSA confirmation in S. aureus.

Main Results:

  • Acinetobacter isolates included Acinetobacter calcoaceticus baumannii complex and A. lwoffii. Approximately 95% of Acinetobacter isolates were MDR, with 12.9% being ESBL producers.
  • Out of 33 S. aureus isolates, 78.8% were MDR, and 42.4% were confirmed as MRSA.

Conclusions:

  • The study identified a high burden of MDR Acinetobacter spp. and MRSA in the studied tertiary care center.
  • The emergence of ESBL-producing Acinetobacter exacerbates the resistance challenge.
  • Judicious antimicrobial use and vigilant laboratory surveillance of resistant strains are imperative.

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