Cytological characterization of persistent paranasal sinus secretions after endoscopic sinus surgery

The aim of this study was to characterize the cellular composition of persisting sinus secretions after endoscopic sinus surgery (ESS).

Consecutive adult patients with persisting abnormal sinus secretions post-ESS were prospectively evaluated. Sinus secretions were aspirated and submitted for cytological analysis. Semiquantitative cell counts were obtained for epithelial cells (graded as present or absent), eosinophils (graded on a 4-point Likert severity scale), and neutrophils (3-point Likert scale). Prior operative histopathology from ESS and Lund CT scores were reviewed. Statistical analyses were conducted to determine the relationships between preoperative Lund score, operative histopathology, and subsequent cellular infiltrate in sinus secretions.

Forty-three patients (mean age, 49 years) were enrolled. Epithelial cells were present in 13 (30.2%) of these individuals. Cytological eosinophilia was rated as absent in 14 (32.6%) cases, mild in 5 (11.6%) cases, moderate in 18 (41.9%) cases, and severe in 6 (14.0%) cases. Neutrophil presence was absent in 24 (55.8%) cases, present/mild in 15 (34.9%) cases, and severe in 4 (9.3%) cases. No significant correlation could be found between the presence of each of these three cell types, the presence or absence of polyps, or preoperative Lund score (all p > 0.05). Sloughed epithelial cell presence was inversely but significantly correlated with original sinus histopathological inflammation (Spearman's rho, -0.348; p = 0.04); eosinophilic cytology tended to increase with prior operative histopathology inflammatory grade but neutrophils did not.

The cytological profile of persisting secretions after ESS is dominated by eosinophils and to a lesser degree neutrophils. The presence of sloughed epithelial cells may signify ongoing mucosal damage from persisting sinonasal inflammation.