The prognostic role of serum eosinophil and basophil levels in sinonasal polyposis

Background Predicting which patients are at a higher risk for recurrent chronic rhinosinusitis with nasal polyps (CRSwNP) is one of the most challenging problems in clinical rhinology. A direct association between CRSwNP recurrence rates and serum eosinophil and basophil counts was reported. This study aimed to identify best-fitting cutoffs for binarizing preoperative serum eosinophils and basophils (counts/percentages) for prognostic purposes in cases of CRSwNP recurrence after surgery. A secondary endpoint was to distinguish said cutoffs for prognosticating recurrence in subcohorts of patients with histologically diagnosed eosinophilic/non-eosinophilic CRSwNP. Methods A retrospective study was performed on 280 patients (127 eosinophilic and 153 non-eosinophilic CRSwNP) examining the prognostic role of serum eosinophil and basophil levels. Results For all patients examined, mean preoperative serum eosinophil and basophil levels were significantly higher in patients whose CRSwNP recurred. Patients with eosinophil counts ≥0.24 cells × 109/L and percentages ≥3.7% had odds ratios (ORs) of 2.57 and 2.19 for recurrence; patients with basophil counts ≥0.03 cells × 109/L and percentages ≥0.5% had ORs of 2.19 and 2.24, respectively. Among histologically eosinophilic CRSwNP patients, mean eosinophils and basophils (counts/percentages) were significantly higher in cases that recurred. Serum eosinophil and basophil values were directly correlated. The recurrence odds were OR 2.52 for high eosinophils (≥5.9%), and OR 2.52 and 2.69 for high basophils (≥0.04 cells × 109/L and ≥0.5%, respectively). Conclusion High serum eosinophil and basophil values should be further investigated because they could pinpoint patients at higher risk of eosinophilic-type CRSwNP recurrence. These preliminary results support the increasing interest in the role of basophils in CRSwNP.