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Changes in frequency and pathogens causing acute otitis media in 1995-2003

Janet R Casey1, Michael E Pichichero

  • 1Elmwood Pediatric Group, Department of Pediatrics, University of Rochester, Rochester, NY, USA.

The Pediatric Infectious Disease Journal
|September 14, 2004
PubMed
Abstract

Insights

High-dose amoxicillin and pneumococcal conjugate vaccines significantly reduced persistent acute otitis media (AOM) and AOM treatment failure (AOMTF). Haemophilus influenzae is now the leading cause, with increased beta-lactamase production.

Area of Science:

  • Pediatrics
  • Infectious Diseases
  • Microbiology

Background:

  • Acute otitis media (AOM) and AOM treatment failure (AOMTF) pose significant challenges in pediatric care.
  • Changes in causative pathogens and treatment guidelines may impact AOMTF rates.

Purpose of the Study:

  • To evaluate the impact of high-dose amoxicillin and pneumococcal conjugate vaccination on pathogens causing persistent AOM and AOMTF.
  • To analyze trends in bacterial isolates and antimicrobial resistance following guideline changes.

Main Methods:

  • A 9-year prospective study involving tympanocentesis in children with persistent AOM or AOMTF.
  • Comparison of three periods: standard-dose amoxicillin, high-dose amoxicillin, and high-dose amoxicillin with pneumococcal vaccination.

Main Results:

  • A significant 24% decline in persistent AOM and AOMTF was observed after 2000 (P = 0.007).
  • Streptococcus pneumoniae decreased (48% to 31%), while Haemophilus influenzae increased (38% to 57%).
  • H. influenzae showed increased beta-lactamase production (P = 0.04), and a trend towards penicillin-susceptible S. pneumoniae was noted.

Conclusions:

  • High-dose amoxicillin and pneumococcal vaccination effectively reduced persistent AOM and AOMTF.
  • H. influenzae has emerged as the predominant pathogen in these cases.
  • Shifts in pathogen prevalence and resistance patterns necessitate ongoing surveillance and treatment strategy evaluation.

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