PATHOGENS

• The bacteriology of chronic sinusitis is less well-defined than acute sinusitis (typically due to Streptococcus pneumonia, Haemophilus influenzae, and Moraxella catarrhalis).
  • A multifactorial disease that, aside from infection, is thought to result from genetics, environmental or occupational exposures, allergies, and immunodeficiencies.
  • Typical respiratory pathogens may cause acute exacerbations of chronic sinusitis noted above.
• Polymicrobial flora is typically found if sinuses are cultured, especially in patients with a history of sinus surgeries, but the role of recovered organisms is often unclear.
  • Gram-negative organisms increased, and possibly anaerobes.
  • Pseudomonas aeruginosa and Staphylococcus aureus are more common in nosocomial and immunocompromised infections.
• Controversy exists over the role of fungi in chronic sinusitis.
  • The suggestion is that fungal elements may incite an eosinophil-mediated immune response in sinonasal mucosa.