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Levofloxacin treatment failure in a patient with fluoroquinolone-resistant Streptococcus pneumoniae pneumonia

Michael B Kays1, David W Smith, Matthew E Wack

  • 1Department of Pharmacy Practice, Purdue University School of Pharmacy and Pharmacal Sciences, Indianapolis, IN 46202-2879, USA.

Pharmacotherapy
|March 20, 2002
PubMed

Insights

Fluoroquinolone resistance in Streptococcus pneumoniae is rising. A patient with pneumococcal pneumonia experienced levofloxacin treatment failure due to high-level resistance, highlighting the need for awareness of local resistance patterns.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Pharmacology

Background:

  • Increasing use of fluoroquinolones for respiratory tract infections has correlated with a rise in fluoroquinolone-resistant Streptococcus pneumoniae.
  • This resistance poses a significant challenge to treating common bacterial infections effectively.

Observation:

  • A case of pneumococcal pneumonia in a patient with a history of three prior levofloxacin treatments is presented.
  • Levofloxacin treatment failed, demonstrating high-level resistance (MIC > 32 microg/ml) and cross-resistance to other fluoroquinolones including moxifloxacin, trovafloxacin, and gatifloxacin.

Findings:

  • Genetic analysis identified specific mutations in the quinolone-resistance determining regions of DNA gyrase (gyrA: Ser81-->Phe) and topoisomerase IV (parC: Ser79-->Phe) as the cause of resistance.
  • The patient was successfully treated with alternative antibiotics, intravenous ceftriaxone followed by oral cefprozil.

Implications:

  • Clinicians must be vigilant regarding local antimicrobial resistance patterns for Streptococcus pneumoniae.
  • The potential for fluoroquinolone treatment failure in patients with S. pneumoniae infections necessitates careful consideration of empirical therapy and susceptibility testing.

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