Predictive Significance of Charcot-Leyden Crystal Protein in Nasal Secretions in Recurrent Chronic Rhinosinusitis with Nasal Polyps

<b><i>Introduction:</i></b> The recurrence occurs frequently among patients with chronic rhinosinusitis with nasal polyps (CRSwNP), and predictors that could be conveniently detected during practice in outpatient service are needed. <b><i>Objective:</i></b> We aimed to illustrate that the concentration of Charcot-Leyden crystal (CLC) in nasal secretions can effectively and noninvasively predict polyp recurrence. <b><i>Methods:</i></b> 108 patients with CRSwNP were divided into recurrence (<i>n</i> = 68) and recurrence-free (<i>n</i> = 40) groups. Preoperative CLC concentrations in nasal secretions were collected and detected by ELISA. Polyp tissues were harvested during biopsy or endoscopic sinus surgery and were evaluated for inflammatory cells by histopathological staining. Demographic information and the clinical characteristics of each patient were reviewed for associations with recurrence. Binary logistic regression analysis was performed to determine predictive factors for polyp recurrence. Receiver operating characteristic (ROC) curves and the Youden index were performed to determine their predictive values. Survival analysis was performed to compare recurrence risk of patients with different CLC concentrations. <b><i>Results:</i></b> Sixty-eight (62.96%) patients developed recurrence during a 12- to 33-month postoperative follow-up. CLC concentrations in nasal secretions were positively correlated with eosinophil percent in polyp tissue and peripheral blood and were significantly higher in patients of the recurrence group than in the patients of the recurrence-free group (<i>p &#x3c;</i> 0.001). Binary logistic regression and ROC curve demonstrated that CLC protein in nasal secretions is predictive of polyp recurrence. According to the Youden index, a CLC concentration of 34.24 ng/mL can predict postoperative polyp recurrence with 92.6% sensitivity and 87.5% specificity. Patients with CLC concentrations higher than the cutoff value yielded a higher risk of recurrence (<i>p &#x3c;</i> 0.001, HR = 11.31, 95% CI: 6.41–19.98). <b><i>Conclusions:</i></b> CLC protein in nasal secretions may serve as a promising noninvasive biomarker to predict CRSwNP recurrence.