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.