Microbiology of chronic frontal sinusitis

Objectives. To determine bacterial and fungal organisms that are present in patients undergoing surgery for chronic frontal sinusitis. Study Design: R etrospective, nonrandomized study. Methods. Retrospective, nonrandomized ba cterial and fungal cultures were performed on 46 sinus aspirates obtained b y frontal sinus trephination performed on 30 consecutive patients with chro nic frontal sinusitis. Results. Six patients were having sinus surgery for the first time, 19 patients had undergone prior functional endoscopic sinus surgery without instrumentation of the frontal sinus/recess, and the third group included 5 patients who had undergone prior frontal sinus/recess sur gery. Preoperative computed tomography scan of the frontal sinuses revealed complete opacification in 63% (29/46 frontal sinuses) and partial opacific ation in 22% (10/46), and no data were available for 15% (7/46). Aerobic cu ltures revealed that 38% (13/35 cultures) had no growth, 21% (7/35) grew St aphylococcus aureus, 21% (7/35) grew coagulase-negative Staphylococcus, 9% (3/35) grew Haemophilus influenzae, and 26% (9/35) grew a variety of other organisms. Anaerobic cultures were positive in 3% (1/32) of sinuses, and fu ngal cultures were positive in 4% (1/24). Haemophilus influenzae was most c ommon in primary cases, whereas coagulase-negative Staphylococcus was most common in patients undergoing revision frontal sinus surgery. There were no other significant differences between cultures from patients undergoing re vision frontal sinus surgery, revision functional endoscopic sinus surgery without prior frontal surgery, and primary surgery. Conclusions: This study suggests that organisms involved in chronic inflammatory disease of the fr ontal sinus may change after previous sinus surgery. The study failed to su pport a significant role for anaerobes. The role for coagulase-negative Sta phylococcus as a potential pathogen or a contaminating agent remains unclea r.