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Updated: Jun 13, 2025
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
Phenotypic and genotypic characterization of methicillin resistant Staphylococcus aureus associated with pyogenic
Sharanya Krishnakumar1, Abdul Azeez Mohamed Khalid2, Jothipandian Sowndarya2
1Department of Microbiology, Sree Balaji Medical College and Hospital, Bharath Institute of Higher Education and Research, Chennai, Tamilnadu, India.
Background And Objectives:
Staphylococcal infections are one of the major infectious diseases affecting globally in spite of advances in development of antimicrobial agents. Knowledge and awareness about the local pattern and prevalence of MRSA infections plays a key role in treatment. The aim of this study was to identify MRSA strains by phenotypic and genotypic methods and to analyze the antibiotic susceptibility pattern of MRSA strains from patients attending a tertiary care hospital.
Materials And Methods:
This study was conducted over a period of 1 year, where 296 isolates of Staphylococcus aureus were isolated from various clinical specimens. The isolated strains were examined for antibiotic susceptibility by the modified Kirby Bauer disc diffusion method. Methicillin resistance was detected by cefoxitin disk diffusion test.
Results:
A total of 104 isolates were found to be MRSA and 192 were found to be MSSA. Among the 104 MRSA isolates, 10 strains that were multidrug resistant were subjected to 16S rRNA gene sequencing analysis. All the 10 strains had a 99% match with S. aureus strains that were responsible for causing some serious biofilm mediated clinical manifestations like cystic fibrosis and device mediated infections. The biofilms were quantified using crystal violet staining and their ability to produce biofilms was analyzed using scanning electron microscopy and matched with the Genbank.
Conclusion:
Hence these phylogenetic analysis aid in treating the patients and combating resistance to antibiotics.
Insights
This study identified methicillin-resistant Staphylococcus aureus (MRSA) strains and analyzed their antibiotic resistance patterns. Phylogenetic analysis of MRSA strains aids in understanding and combating antibiotic resistance in clinical settings.
Area of Science:
- Microbiology
- Infectious Diseases
- Genetics
Background:
- Staphylococcal infections remain a global health concern despite antimicrobial advancements.
- Understanding local patterns of Methicillin-Resistant Staphylococcus aureus (MRSA) is crucial for effective treatment.
- MRSA poses significant challenges in healthcare settings worldwide.
Purpose of the Study:
- To identify MRSA strains using both phenotypic and genotypic methods.
- To determine the antibiotic susceptibility patterns of MRSA isolates.
- To investigate the genetic relatedness and biofilm-forming potential of multidrug-resistant MRSA strains.
Main Methods:
- Phenotypic antibiotic susceptibility testing using the modified Kirby Bauer disc diffusion method.
- Detection of methicillin resistance using the cefoxitin disk diffusion test.
- Genotypic analysis including 16S rRNA gene sequencing and biofilm quantification via crystal violet staining and scanning electron microscopy.
Main Results:
- Out of 296 Staphylococcus aureus isolates, 104 were identified as MRSA and 192 as MSSA.
- Ten multidrug-resistant MRSA strains showed a 99% match with S. aureus strains linked to serious biofilm-mediated infections.
- Biofilm formation was quantified and analyzed using advanced microscopy techniques.
Conclusions:
- Phylogenetic analysis of MRSA strains provides valuable insights for patient treatment.
- Understanding MRSA epidemiology and resistance mechanisms is essential for combating antibiotic resistance.
- Genotypic characterization aids in managing complex staphylococcal infections.
