The bacterial microbiome in chronic rhinosinusitis: Richness, diversity, postoperative changes, and patient outcomes

Background: The bacterial microbiome in chronic rhinosinusitis (CRS) remains poorly understood. Microorganisms are believed to be important contributors to the inflammatory response seen in these patients. Objective: To examine the bacterial CRS microbiome by using a pyrosequencing technique and determine the diversity, richness, prevalence, and abundance of bacterial species in these patients. Furthermore, the postoperative changes that occur in the microbiome and correlations with patient outcomes are assessed. Methods: Swabs were collected from 23 patients with CRS and 11 controls during surgery. Further postoperative swabs were collected in the CRS group. Bacterial DNA was extracted from the swabs and then sequenced by using 16S ribosomal DNA bacterial tag-encoded FLX amplicon pyrosequencing. Results: A total of 456 unique bacterial species were detected. No difference was seen for richness or diversity between the study groups (p > 0.05). Diversity declined after surgery in the CRS group (p = 0.01). Propionibacterium acnes and Staphylococcus epidermidis were the most prevalent species. Several significant differences were determined for prevalence and mean relative abundance (MRA) between the study groups. In particular, Acinetobacter johnsonii was more prevalent and had a higher MRA in the controls. Furthermore, the MRA of this species increased after surgery and was associated with improved quality of life. Conclusion: This study characterized the sinonasal microbiome in a group of controls and patients with CRS. Important differences in diversity, prevalence, abundance, and temporal changes were described. Of great interest is the potential association between A. johnsonii and health. These findings provide new insights into the interplay between the microbiome and health in the paranasal sinuses.