[Association between plasma inflammatory mediators and histological endotypes of nasal polyps]

Objective: To compare the clinical characteristics and plasma inflammatory markers levels in different endotypes of chronic rhinosinusitis with nasal polyps (CRSwNP), and to explore the plasma biomarkers associated with endotypes of CRSwNP. Methods: A total of 74 CRSwNP patients (male/female: 41/33; average age: 40 years) and 40 control subjects underwent septoplasty in Tongji Hospital from January 2015 to December 2017 were enrolled in this study. The demographic and clinical features of all subjects including age, gender, past history, visual analogue scale (VAS) and CT scores were recorded. Patients with CRSwNP were divided into Eos^highNeu^high, Eos^highNeu^low, Eos^lowNeu^high and Eos^lowNeu^low four endotypes according to the eosinophil (Eos) percentage and neutrophil (Neu) count of nasal polyps tissue. Preoperative blood routine was performed and the levels of 27 biomarkers in plasma were measured by Bio-Plex suspension chip method. The clinical characteristics and the level of serum biomarkers of patients with different endotypes were compared. SPSS 18.0 software was used for statistical analysis. Results: There was no difference in the clinical features including gender ratio, age, course of disease, VAS score, endoscopy and CT score among Eos^highNeu^high, Eos^highNeu^low, Eos^lowNeu^high and Eos^lowNeu^low CRSwNP patients. Compared with Eos^lowNeu^high and Eos^lowNeu^low CRSwNP patients, patients with Eos^highNeu^high and Eos^highNeu^low endotype demonstrated a higher prevalence of atopy, allergic rhinitis and asthma comorbidity, and increased peripheral blood eosinophil absolute count and percentage (all P<0.05). However, there was no significant difference between Eos^highNeu^high and Eos^highNeu^low CRSwNP. Plasma levels of all 27 mediators including type 1 cytokines (IL-12 and IFN-γ), type 2 cytokines (IL-4, IL-5 and IL-13), type 3 cytokines (IL-17A), pro-inflammatory cytokines (IL-6 and TNF-α) and tissue remodeling-related markers (bFGF, VEGF and PDGF-BB) demonstrated no significant difference among all endotypes of CRSwNP (all P>0.05). Conclusions: Eos^high and Eos^low CRSwNP patients display significant differences regarding the prevalence of atopy, allergic rhinitis and asthma comorbidity, peripheral blood eosinophil absolute count and percentage, but the clinical characteristics, blood cellular and biological markers can not effectively distinguish four endotypes of CRSwNP. Further studies are warranted to dig out the potential objective, convenient and reliable markers associated with endotypes in patients with CRSwNP.