Correlating matrix metalloproteinase‐9 sinus secretion levels with tissue biopsy levels

BACKGROUND: Collecting mucosal biopsies is invasive and creates additional inflammation, hampering a better understanding of nasal and sinus disease evolution and response to treatment. We examine whether sinus secretion collection can replace tissue biopsy for protein determination. METHODS: Prior to surgical intervention for chronic rhinosinusitis (CRS), a piece of gelatin foam was used to collect secretions from the ethmoid mucosa. A tissue biopsy was then taken from the same location. Matrix metalloproteinase-9 (MMP-9) protein levels were measured in each sample. RESULTS: MMP-9 protein levels in secretions and tissues were significantly correlated (p = 0.0033, r = 0.52, by Pearson correlation). CONCLUSION: Secretion collection can replace tissue biopsy for MMP-9 determinations, reducing morbidity. Furthermore, secretion collection allows sequential sampling from the same location.