Bacteriology of normal frontal sinuses

Abstract Purpose The aim of this cross-sectional trial was to identify the bacterial flora and to quantify the level of bacterial presence in healthy adult frontal sinus cavities. Materials and methods Ninety five consecutive patients undergoing craniotomy of the anterior cranial fossa were enrolled. All patients were evaluated preoperatively by a sino-nasal questionnaire, nasal endoscopy and CT scan. Exclusion criteria were patients with sinus tumours, presenting a cold in the past 8 weeks, having signs or symptoms suggestive of sinus disease, history suggestive of allergic rhinitis and/or asthma, having undergone hospitalization or an outpatient clinic visit within the past 12 months, patients with known systemic disease, having previous sinus or nose surgery, history of trauma of the sino-nasal region, or having used systemic antibiotics, steroids, or nasal spray in the past 8 weeks. Lavages were obtained from frontal sinuses before craniotomy through trephination of the anterior wall. The sinus was irrigated with sterile saline followed by aspiration. Specimens were inoculated for aerobic and anaerobic organisms. Results After applying the exclusion criteria, 42 patients (84 sinuses) were finally included in the study. Bacterial organisms were recovered in 12 of 84 (14.28%) sinuses. However, 85.72% of the sinuses were found to be sterile. Bacteria recovered included three different coagulase-negative staphylococci, one Citrobacter diversus and two Micrococcus spp. No anaerobic organism was isolated. Conclusions This study demonstrated that the majority of frontal sinuses of asymptomatic adults with normal CT and endoscopic appearance are sterile.