A study on nosocomial pathogens in ICU with special reference to multiresistant Acinetobacter baumannii harbouring
R B Patwardhan1, P K Dhakephalkar, K B Niphadkar
1Department of Microbiology, University of Pune, Pune, India.
The Indian Journal of Medical Research
|November 13, 2008
Summary
Antibiotic-resistant Acinetobacter baumannii is a significant threat in intensive care units, often linked to transferable plasmids. Targeting this pathogen is crucial for managing nosocomial infections.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Nosocomial infections caused by antibiotic-resistant bacteria pose a major challenge in intensive care units (ICUs).
- Acinetobacter baumannii is a key pathogen frequently implicated in ICU-acquired infections.
- Understanding the mechanisms of antibiotic resistance, particularly plasmid-mediated transfer, is critical for effective treatment strategies.
Purpose of the Study:
- To investigate antibiotic resistance patterns in Acinetobacter baumannii and other pathogens from ICU clinical samples.
- To specifically examine plasmid-mediated transferable antibiotic resistance in Acinetobacter.
- To determine the prevalence and characteristics of nosocomial pathogens in the ICU setting.
Main Methods:
- Analysis of 272 clinical specimens from ICUs to identify nosocomial pathogens and their antibiotic resistance profiles.
- Identification of Acinetobacter isolates using the API2ONE system and determination of Minimum Inhibitory Concentrations (MICs).
- Plasmid profiling of resistant Acinetobacter isolates, including plasmid curing experiments and transformation studies to assess transferability.
Main Results:
- Acinetobacter baumannii was a predominant pathogen, particularly in urinary tract infections (44.4%) and wound infections (29.4%).
- Acinetobacter isolates exhibited high-level resistance to numerous antibiotics, with over 90% resistant to at least 23 different agents.
- Plasmid analysis confirmed the presence of transferable resistance markers in Acinetobacter baumannii, with successful plasmid transfer demonstrated via transformation.
Conclusions:
- Acinetobacter baumannii is a significant cause of diverse nosocomial infections in ICUs, including UTIs, respiratory infections, and wound infections.
- The high level of antibiotic resistance in A. baumannii is largely attributed to plasmid-borne genes, facilitating horizontal gene transfer.
- Effective control of nosocomial infections necessitates targeted strategies against Acinetobacter baumannii due to its resistance and transmissibility.
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