Endoscopically guided sinonasal cultures: a direct comparison with maxillary sinus aspirate cultures.

Sinusitis is a common medical problem that can at times be challenging to treat. Although most cases respond to empiric therapy, success is not achieved universally. If empiric therapy fails, it is important to identify the causative bacterial pathogen. Antral puncture is the traditional diagnostic method to recover and identify pathogens in sinusitis; however, it remains a painful, invasive test with potential complications. In contrast, rigid sinonasal endoscopy permits recovery of mucopus emanating from the sinus ostia with little pain and few possible complications. Endoscopy also affords important visual information that can confirm or refute a historical/clinical diagnosis of sinusitis. Although previous studies have shown poor correlation between nasal cavity swab cultures and maxillary sinus aspiration cultures, few investigations have compared endoscopically guided middle meatal cultures with cultures obtained from maxillary sinus aspiration. Thirteen patients with maxillary sinusitis in one or both sinuses underwent endoscopically guided culture of the middle meatus and maxillary sinus puncture with aspiration and culture (16 total study samples). Results from the microbiologic analysis were compared. Endoscopically guided middle meatal cultures accurately identified the predominant bacterial pathogen and correlated with the cultures from maxillary sinus aspiration in more than 90% of infections. These preliminary results suggest that endoscopically guided sinonasal cultures hold promise as a viable alternative to maxillary sinus aspiration. Endoscopically guided cultures appear to be an effective, noninvasive diagnostic tool for otolaryngologists managing sinusitis.