Resident Physician University of North Carolina at Chapel Hill Chapel Hill, North Carolina
Background: Sampling chemical mediators in the sinonasal mucosa has typically been accomplished through sinonasal lavage (SNL). This method is not specific for location within the paranasal sinuses, dilutes analytes and prevents subsite analysis within the sinuses. Recent advancements in sampling technology allows for consistent and highly concentrated extraction of nasal mucosa proteins, permitting site specific analysis of inflammatory proteins throughout the sinonasal cavity. In this study, we examined site specific differences between the mucosa of the inferior turbinate (IT), middle meatus (MM) and the sphenoethmoidal recess (SER).
Methods: Leukosorb paper strips were placed bilaterally at either the head of the IT, MM or SER under direct endoscopic visualization. Epithelial lining fluid (ELF) was collected and analyzed via direct enzyme-linked immunosorbent assay (ELISA) for 30 key inflammatory mediators. Two-way ANOVA analysis was conducted to determine significance between sites.
Results: A majority of inflammatory markers assayed (73.3%) had similar levels between distinct sub-sites. A subset of markers was differentially expressed between sites. Eotaxin and MIP1-alpha were more highly expressed at the MM, Eotaxin-3 was more highly expressed at the SER, and IL2, IL4, IL6, IL15 and IFN-gamma were more highly expressed at the MM.
Conclusions: Site-specific ELF testing of inflammatory mediators within the sinonasal cavity can be accomplished with a high degree of repeatability. There is not significant variability between sites; however, in our preliminary study we noted small, persistent site-specific changes in certain chemical mediators. Additional work is needed to better understand this variability.