infective organisms

Last reviewed 01/2018

• bacterial causes include:
  • Strep pneumonia - 30%
  • H. influenzae - 20%
  • Moraxella catarrhalis - 20%
  • Group A Strep and Staph aureus - 5%
• viral causes (less than 10%) (1):
  • polymerase chain reaction (PCR) has shown detectable virus in the middle ear space
  • respiratory viral infection predisposes to bacterial infection (1)
• coinfection with bacteria is present in more than 40 percent viral-induced acute otitis media (2)
• associated viruses include (1,2):
  • RSV
  • parainfluenzae
  • influenza virus
  • rhinovirus
  • enterovirus
• Mycoplasma pneumoniae, Chlamydia pneumoniae, Chlamydia trachomatis are rare causes

Reference:

• (1) Acute otitis media:virtual classroom of the American Academy of Paediatrics
• (2) Kalyanakrishnan R et al. Diagnosis and treatment of otitis media.Am Fam Physician  2007; 76:1650-8, 1659-60