Correlation Between Bone Morphogenic Protein-2 (BMP-2) Levels With Global Osteitis Scoring Scale (GOSS) and Endotype Biomarkers in Chronic Rhinosinusitis

Introduction: Chronic rhinosinusitis (CRS) is a nasal and sinus inflammation. It's divided into primary and secondary types, distinguishable by biomarkers. In general, endotypes in primary CRS classified into type 2 and non-type 2 (combination of type 1 and type 3) based on specific inflammatory mediators, immune cells, and physiological functions. Paranasal sinus osteitis, a bone change due to inflammation, occurs in primary CRS marked with the damage of lamellar bone structure and new bone formation. Bone morphogenetic protein 2 (BMP-2) is a potential biomarker for bone formation in CRS. Osteitis severity is measured by the Global Osteitis Scoring Scale (GOSS). This study aims to analyze the correlation between BMP-2, GOSS, and inflammation subtypes in primary CRS. Methods: An analytic, cross-sectional study was conducted on 33 primary CRS patients. BMP-2 and endotype biomarkers were measured in uncinate process tissue using ELISA. Normal BMP-2 and endotype biomarkers levels were determined from non-CRS nasal tissue. Osteitis was evaluated using CT scans and GOSS. Results: BMP-2 level has no significant difference in endotype 2 and non-type 2 CRS. BMP-2 level had a significant correlation with IL-5 (endotype 2) (p value = 0.00) and OSM (non-type 2) (p value = 0.00). BMP-2 did not correlate with GOSS values in endotype 2 or non-type 2. Conclusion: Type 2 CRS had slightly higher BMP-2 levels, correlating more with IL-5 and OSM. However, BMP-2 did not correlate with osteitis severity (GOSS), suggesting a minor role in CRS osteitis.