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Topical ocular antibiotics induce bacterial resistance at extraocular sites

B D Gaynor1, J D Chidambaram, V Cevallos

  • 1Department of Ophthalmology, F I Proctor Foundation, 95 Kirkham Street, Room 307, University of California San Francisco, San Francisco, CA 94143-0944, USA.

The British Journal of Ophthalmology
|August 23, 2005
PubMed

Insights

Mass antibiotic treatments for trachoma control can increase drug-resistant Streptococcus pneumoniae. Both oral azithromycin and topical tetracycline showed increased resistance, suggesting topical antibiotics impact nasopharyngeal bacterial resistance.

Area of Science:

  • Medical Microbiology
  • Public Health
  • Infectious Diseases

Background:

  • Trachoma control programs often utilize mass antibiotic administration.
  • The impact of these treatments on nasopharyngeal bacterial resistance, particularly Streptococcus pneumoniae, is not fully understood.
  • Understanding resistance patterns is crucial for effective antibiotic stewardship.

Purpose of the Study:

  • To compare antibiotic resistance in nasopharyngeal Streptococcus pneumoniae.
  • To assess resistance following topical tetracycline or systemic azithromycin treatment for trachoma.
  • To evaluate the effect of mass antibiotic administration on antibiotic resistance.

Main Methods:

  • Children (1-10 years) in trachoma-endemic villages received annual oral azithromycin or topical tetracycline for 3 years.
  • Nasopharyngeal carriage of S. pneumoniae was surveyed 6 months after the third treatment.
  • Antibiotic resistance was determined using broth dilution MIC technique.

Main Results:

  • S. pneumoniae carriage rates were similar across treated and untreated villages.
  • Antibiotic resistance patterns differed significantly between treatment groups (p=0.004).
  • Topical tetracycline treatment correlated with higher tetracycline resistance (p=0.010), while oral azithromycin correlated with higher macrolide resistance (p=0.014).

Conclusions:

  • Annual mass oral azithromycin treatment can alter the prevalence of drug-resistant S. pneumoniae.
  • Topical tetracycline treatment may also increase nasopharyngeal pneumococcal resistance.
  • Topical antibiotic use could potentially influence extraocular bacterial resistance patterns.
Abstract

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