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Penicillin-susceptible and erythromycin-resistant Streptococcus pneumoniae in children with acute mastoiditis

F del Castillo1, F Ledesma, A García-Perea

  • 1Pediatric Infectious Disease Unit, Children's University Hospital La Paz, Madrid, Spain. fdm02m@nacom.es

European Journal of Clinical Microbiology & Infectious Diseases : Official Publication of the European Society of Clinical Microbiology
|January 11, 2002
PubMed

Insights

Penicillin-susceptible and erythromycin-resistant Streptococcus pneumoniae strains are increasingly causing acute otitis media with acute mastoiditis in children. This study investigated these resistant Streptococcus pneumoniae isolates in Madrid.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pediatrics

Background:

  • Erythromycin resistance in Streptococcus pneumoniae typically correlates with penicillin resistance.
  • An emerging trend of penicillin-susceptible, erythromycin-resistant Streptococcus pneumoniae has been observed in pediatric acute otitis media cases complicated by acute mastoiditis.

Purpose of the Study:

  • To analyze the prevalence and characteristics of Streptococcus pneumoniae isolates exhibiting a penicillin-susceptible and erythromycin-resistant profile.
  • To investigate the clinical significance of this specific antibiotic resistance pattern in pediatric mastoiditis.

Main Methods:

  • Retrospective review of a microbiology database.
  • Analysis of Streptococcus pneumoniae isolates from patients with acute otitis media and acute mastoiditis.
  • Characterization of antibiotic susceptibility profiles, focusing on penicillin and erythromycin.

Main Results:

  • Identification of an increasing number of Streptococcus pneumoniae isolates with a distinct penicillin-susceptible and erythromycin-resistant phenotype.
  • These isolates were specifically associated with complicated acute otitis media cases leading to acute mastoiditis in children.

Conclusions:

  • The emergence of penicillin-susceptible, erythromycin-resistant Streptococcus pneumoniae poses a diagnostic and therapeutic challenge in pediatric mastoiditis.
  • Further research is needed to understand the mechanisms and epidemiological spread of this resistance pattern.

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