Correlation of middle meatus and ethmoid sinus microbiology in patients with chronic sinusitis.

Empirical antibiotics constitute the cornerstone of medical therapy for chronic sinusitis due to difficulties of obtaining cultures from the paranasal sinuses. Indirect isolation of the pathogenic microorganisms outside the paranasal sinuses with a non-invasive method may enable administration of specific antibiotics. In this prospective study, we obtained cultures from the middle meatus and ethmoid sinuses of 193 sides from 127 patients who had undergone FESS for chronic sinusitis with a method that minimizes the risk of nasal contamination. The same bacterial species were isolated from both the ethmoid sinus and middle meatus in 59.3% of the cultures. There was no bacterial growth in either site in 32.3% of the cultures. The overall correlation rate of middle meatus and ethmoid sinus cultures was estimated to be 91.6%. In conclusion, middle meatal cultures can be used for the isolation of pathogenic microorganisms indirectly, while administration of specific antibiotics can be possible according to the results of these cultures.