High tissue eosinophilia as a marker to predict recurrence for eosinophilic chronic rhinosinusitis: a systematic review and meta‐analysis

Background Patients with eosinophilic chronic rhinosinusitis (ECRS) have been shown to have greater disease severity and poorer treatment outcomes after sinus surgery. Although the inflammatory pattern of ECRS is essential to diagnosing this subtype, there is currently no consensus for diagnosis. Our aim in this study was to determine whether high tissue eosinophilia (HTE), measured as eosinophils per high‐power field (eos/HPF), could be used to define ECRS based on likelihood of recurrence. Methods Embase, Medline, and PubMed databases were searched for studies that reported HTE and recurrence in ECRS patients after surgical treatment. We used a random‐effects bivariate meta‐analysis to calculate summary sensitivity, specificity, and diagnostic odds ratios (DORs) for detecting ECRS at different HTE cut‐off scores using risk of recurrence as the primary outcome. Results We identified 11 articles (n = 3183) that reported HTE associated with recurrence. A cut‐off value of >55 eos/HPF showed the highest sensitivity (0.87; 95% confidence interval [CI], 0.82‐0.91), specificity (0.97; 95% CI, 0.93‐0.99), and DOR (232.7; 95% CI, 91.0‐595.1). Meta‐regression analysis performed showed that the Quality Assessment of Diagnostic Accuracy Studies score (p = 0.1287), geographic location (p = 0.3745), follow‐up time (p = 0.2879), and study design (p = 0.1865) did not affect the test accuracy. Conclusion Our findings suggest that using eos/HPF has good diagnostic accuracy and may be a useful tool for identifying ECRS patients. Based on the results of our meta‐analysis, we recommend a cut‐off value of >55 eos/HPF for predicting the likelihood of recurrence of ECRS.