Exploring Endotypes in Chronic Rhinosinusitis (ExpRess): Protocol for a cohort study

Area of Science:

• Immunology
• Otorhinolaryngology
• Microbiome research

Background:

• Chronic Rhinosinusitis (CRS) affects 1 in 10 UK adults, significantly impacting quality of life.
• Treatment response in CRS may depend on individual endotypes, necessitating research into biomarker clusters.
• The MACRO trial is a three-arm study randomizing adult CRS patients to surgery, macrolide therapy, or placebo.

Purpose of the Study:

• To correlate Chronic Rhinosinusitis (CRS) endotypes with clinical parameters from the MACRO trial.
• To analyze olfactory function and treatment response using core biomarker sets.
• To identify biomarkers that differentiate between responders and non-responders to CRS treatments.

Main Methods:

• Recruitment of adult CRS patients from UK otorhinolaryngology departments participating in the MACRO trial.
• Collection of nasal tissue and swabs for analysis of 32 cytokines (e.g., IL-5, IL-13, IgE, periostin) via multiplex electrochemiluminescence.
• 16S amplicon sequencing of bacterial swabs to analyze the nasal microbiome.

Main Results:

• Mean biomarker expression will be reported for treatment responder and non-responder groups.
• Correlation of identified biomarkers with MACRO trial outcome data, including endoscopic scores and quality-of-life improvements.
• Analysis of specific biomarkers like IL-5, IL-13, IgE, and periostin in relation to treatment outcomes.

Conclusions:

• Defining clear endotypes in Chronic Rhinosinusitis (CRS) will refine patient pathways and optimize clinical resource allocation.
• This research may enable future prediction of patient response to medical or surgical therapies.
• Biomarker discovery is crucial for personalized treatment strategies in CRS.