Bacterial Cultures of the Middle Meatus and Bronchoalveolar Lavage in Chronic Rhinosinusitis

Abstract

The role of bacteria in chronic rhinosinusitis (CRS) is still debated and their effect on the lower airways is less known. The aim of this study was to identify the individual bacterial species in CRS and to correlate these microbiological data with the clinical findings and associated bacterial cultures of the lower airways. This prospective study included 25 CRS patients scheduled for functional endoscopic sinus surgery. Preoperatively, pulmonary function and CT examinations were performed together with endoscopic and clinical assessment. Under aseptic conditions, with the patient under general anesthesia, 25 bronchoalveolar lavages (BALs) via the endotracheal tube and 50 endoscopically guided middle meatal specimens were obtained. All the specimens were examined for aerobic and anaerobic bacteria and correlated to the associated neutrophilic cellular changes. Positive bacterial cultures were obtained in 71% of the middle meatal specimens and 8% of the BAL specimens. Three subgroups of lower airway involvement were identified, i.e. asthma, small airway disease (SAD) and normal lower airways. In SAD only, there was a significant correlation between the cultured bacteria of the left (p = 0.04) and the right (p = 0.04) middle meatus and the presence of local neutrophilia. In asthma, middle meatal bacterial cultures correlated with nasal blockage (p = 0.04) and CT Lund-Mackay score (p = 0.04). Conclusion: Middle meatal cultures were frequently positive, mainly aerobic Gram-positive bacteria. In SAD, a mixed flora of Gram-positive aerobic bacteria and anaerobic bacteria was observed that correlated with neutrophilic inflammation. BAL cultures do not show infection or colonization of the lower airways, despite functional abnormalities in 60% of the patients.