USA: Higher IL-17A Levels Associated with Increased Sinus Surgeries for CRS

A recent study in the International Forum of Allergy & Rhinology finds that higher IL-17A levels are associated with an increased number of prior sinus surgeries for chronic rhinosinusitis (CRS). The findings suggest that the presence of type 3 inflammatory markers may indicate a particularly difficult-to-treat, recalcitrant CRS endotype.

The identification of potential inflammatory endotypes of CRS has been made possible due to recent advances in molecular biology. Prior work has suggested differential short-term surgical outcome trajectories based on cytokine signatures. However, there is a lack of data assessing long-term treatment failure and the need for revision surgery based on inflammatory biomarkers.

To address this, Nikita Chapurin from Vanderbilt University Medical Center, Nashville, TN, USA, and colleagues performed a retrospective analysis of prospectively collected cross-sectional data from 231 patients electing surgical therapy for CRS.

The researchers quantitatively sampled intraoperative mucus specimens for inflammatory cytokines using a multiplex flow cytometric bead assay. Univariate Spearman correlations between cytokine levels and the number of prior surgeries were assessed. Patient-reported prior sinus surgery counts as a function of cytokine levels were modeled using a stepwise adjusted multivariate Poisson regression analysis.

Key Findings of the Study

• Several cytokines (interleukin [IL]-1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, IL-17A, tumor necrosis factor α [TNF-α], interferon γ [IFN-γ], and eotaxin) demonstrated significant positive correlations with the number of prior surgeries.
• Only higher IL-17A levels were independently associated with a higher number of prior sinus surgeries (β = 0.345) after adjusting for significant covariates such as age (β = 0.018), Lund-Mackay score (β = –0.046), history of aspirin-exacerbated respiratory disease (β = 1.01), and allergic fungal rhinosinusitis (β = 1.08).
• Higher levels of regulated on activation, normal T-cell expressed and secreted (RANTES) were conversely associated with a lower number of prior surgeries (β = –0.17).

"An IL-17A–predominant cytokine profile is linked to an increased number of prior sinus surgeries. Thus, type 3 inflammatory markers may indicate a particularly difficult-to-treat, recalcitrant CRS endotype," wrote the authors.

The study titled, "Elevated mucus interleukin-17A levels are associated with increased prior sinus surgery for chronic rhinosinusitis," is published in the journal International Forum of Allergy & Rhinology.

DOI: https://onlinelibrary.wiley.com/doi/abs/10.1002/alr.22652