Biomarker Identifies CRSwNP Endotypes, Risk of Postoperative Nasal Polyp Recurrence

Findings published in International Immunopharmacology identified circulating B cell–activating factor (BAFF) as a potential biomarker for distinguishing endotypes of chronic rhinosinusitis with nasal polyps (CRSwNP), as well as postoperative disease recurrence risk.

Characterized by its highly heterogeneous nature, CRSwNP pathogenesis was explained by researchers to be the accumulation of inflammatory cells and corresponding inflammatory mediators in mucosal tissue.

“Based on the degree of mucosal eosinophil infiltration, CRSwNP is further divided into eosinophilic CRSwNP or noneosinophilic CRSwNP,” they added. “In a disease with such a high heterogeneity and recurrence rate, exploring novel biomarkers for distinguishing CRSwNP endotypes and predicting postoperative recurrence is an urgent need.”

With prior research having cited BAFF as a mediating factor in the activation and migration of eosinophils for several inflammatory/autoimmune diseases, such as rheumatoid arthritis and dermatomyositis, the study authors sought to explore its potential role in the pathogenesis of CRSwNP endotypes and postoperative recurrence.

They conducted a long-term prospective study of 120 patients with CRSwNP who underwent nasal endoscopic surgery between June 2017 and September 2017 at Hainan General Hospital, China. Participants were followed for more than 3 years, in which 68 patients presented with noneosinophilic CRSwNP (mean [SD] age, 43.1 [17.2] years) and 52 patients presented with eosinophilic CRSwNP (mean age, 41.6 [15.8] years); there were also 60 healthy controls (mean age, 41.3 [14.7] years)

“Circulating BAFF levels of all participants were measured by enzyme-linked immunosorbent assay, and receiver-operating characteristic (ROC) and logistic regression analyses were applied to assess the predictive ability of BAFF levels in distinguishing CRSwNP endotypes,” the researchers said.

Of the study cohort, serum BAFF levels were shown to be elevated in patients with CRSwNP overall compared with controls (P < .01). Patients with eosinophilic disease presented with significantly higher levels vs those with noneosinophilic disease (P < 0.05).

Increased serum BAFF concentrations were indicated to be positively correlated with blood eosinophil counts and percentages, tissue eosinophil counts, and serum total immunoglobulin E (P < .05). Findings of the ROC curve further showed that serum BAFF exhibited strong discriminative ability for patients with eosinophilic CRSwNP.

Ninety-nine patients with CRSwNP completed the follow-up schedule, with 65 patients classified into the nonrecurrence group and the other 34 patients placed into the recurrence group.

Among these groups, serum BAFF levels were significantly higher in the recurrence vs nonrecurrence group (P < .001), and the ROC curve suggested a high predictive value of serum BAFF in predicting postoperative recurrence. Logistic regression and Kaplan-Meier curves additionally confirmed that serum BAFF was an independent risk factor for postoperative nasal polyps recurrence (P < .05).

“Our data suggested that serum BAFF levels were upregulated in CRSwNP patients and correlated with mucosal eosinophil infiltration severity,” concluded the researchers. “Serum BAFF seemed to be a novel biomarker for preoperatively distinguishing CRSwNP endotypes and predicting postoperative recurrence.”

Reference

Wang G, Li M, Zheng J, et al. Circulating BAFF as novel biomarker in distinguishing chronic rhinosinusitis with nasal polyps endotypes and predicting postoperative recurrence. Int Immunopharmacol. 2022;104:108515. doi:10.1016/j.intimp.2021.108515