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Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance
09:59

Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance

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[Salmonella of Indian origin: pseudo-susceptibility to fluoroquinolones]

E Denes1, G Gondran, H Bezanahary

  • 1Service des maladies infectieuses et tropicales, CHU Dupuytren, 2, avenue Martin-Luther-King, 87042 Limoges cedex, France. eric.denes@unilim.fr

Medecine Et Maladies Infectieuses
|May 26, 2005
PubMed

Insights

A typhoid fever case in India resistant to ciprofloxacin highlights fluoroquinolone resistance. Nalidixic acid MIC may predict resistance, suggesting alternative antibiotics for travelers.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Pharmacology

Background:

  • Typhoid fever is a significant global health concern, particularly in endemic regions like India.
  • Fluoroquinolones are commonly prescribed for typhoid fever, but antimicrobial resistance is a growing challenge.

Observation:

  • A patient returning from India developed typhoid fever unresponsive to ciprofloxacin treatment.
  • Standard antibiogram did not detect reduced susceptibility, but a high Minimum Inhibitory Concentration (MIC) for nalidixic acid (>32 mg/l) was noted.

Findings:

  • The typhoid-causing bacteria exhibited reduced susceptibility to fluoroquinolones, a resistance not identified by routine testing.
  • Elevated MIC for nalidixic acid and norfloxacin can serve as early indicators of fluoroquinolone resistance.

Implications:

  • For travelers from high-risk areas, consider third-generation cephalosporins over fluoroquinolones for typhoid treatment.
  • Implementing MIC testing for nalidixic acid and norfloxacin could improve early detection of fluoroquinolone resistance in Salmonella Typhi.

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