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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Inducible clindamycin resistance in Staphylococcus aureus: a study from North India

V Gupta1, P Datta, H Rani

  • 1Department of Microbiology, Government Medical College Hospital, Chandigarh, India. varshagupta_99@yahoo.com

Journal of Postgraduate Medicine
|November 4, 2009
PubMed
Abstract

Insights

A significant percentage of Staphylococcus aureus strains exhibit inducible clindamycin resistance (iMLS(B)), a concerning trend in both community and hospital settings. Routine D-testing is recommended for accurate susceptibility reporting.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Antimicrobial resistance in Staphylococci is a growing global health concern.
  • Macrolide resistance mechanisms include efflux (msrA) or enzymatic inactivation (erm genes).
  • Inducible clindamycin resistance (iMLS(B)) poses a challenge for treatment selection.

Purpose of the Study:

  • Determine the prevalence of inducible clindamycin resistance (iMLS(B)) in Staphylococcus aureus using the D-test.
  • Investigate the association between Methicillin-resistant Staphylococcus aureus (MRSA) and iMLS(B).
  • Analyze the community versus nosocomial distribution of iMLS(B) isolates and discuss treatment implications.

Main Methods:

  • Studied 200 non-duplicate Staphylococcus aureus isolates from clinical samples.
  • Antimicrobial susceptibility testing performed using Kirby Bauer method.
  • Methicillin resistance detected via oxacillin disc diffusion; D-test employed for inducible clindamycin resistance detection.

Main Results:

  • Out of 200 isolates, 50 (25%) were MRSA and 36 were D-test positive for iMLS(B).
  • MRSA isolates demonstrated higher rates of both inducible and constitutive clindamycin resistance compared to MSSA.
  • iMLS(B) isolates were more prevalent in the outpatient (community) setting (66.67%) than in indoor (hospital) patients (33.33%).

Conclusions:

  • A high incidence of iMLS(B) was observed in both community and hospital settings.
  • Clindamycin susceptibility testing, including D-testing, is crucial for guiding therapy, especially for MRSA infections.
  • Clinical microbiology laboratories should routinely report inducible clindamycin resistance.

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