Effectiveness of Oral Steroid Administration for Eosinophilic Sinusitis

Special attention has been recently paid to chronic sinusitis with marked eosinophilic infiltration given its resistance to conservative as well as surgical treatment. This pathology is now classified as eosinophilic sinusitis (ES). Several reports suggest that systemic steroid administration is effective and necessary as maintenance therapy after surgery. However, the optimal doses and duration of steroid therapy following surgery remain unknown. The present study was performed to examine the effectiveness of oral steroid therapy for ES after endoscopic sinus surgery (ESS). Two hundred and three patients with chronic sinusitis complicated with nasal polyps who underwent ESS in the ENT clinic of Kagoshima University Hospital from January 2000 to December 2003 were enrolled in the study. Biopsy of nasal polyp was performed prior to ESS, and ES was diagnosed by the histological findings of more than 60 eosinophils/field at the magnification of 200. ES cases were classified into two groups based on clinical records; one group was orally administered with steroid after ESS (SG), the other group did not receive steroid after ESS (NSG). Topical findings and laboratory data such as eosinophils and eosinophil cationic protein (ECP) within peripheral blood were compared between the SG and NSG groups. In the results, ES was observed in 30 out of 203 (15%) cases of sinusitis. ES was complicated with asthma in 63%, and with allergic rhinitis in 33%. Recurrence of nasal polyp was statistically less in SG than in NSG. Oral steroid administration was particularly effective in patients with both ES and asthma. Decreased nasal polyp recurrence rates were observed in patients with lower peripheral blood eosinophil counts and lower serum ECP levels. Those findings indicate that oral steroid therapy is effective to reduce recurrence in patients with ES by decreasing the number of activated eosinophils in peripheral blood.