The study will be conducted to identify factors predicting the response of chronic rhinosinusitis with nasal polyps ( CRSwNP) to oral corticosteroids.

Treatment of nasal polyposis is divided into medical or surgical treatment .

Steroids are widely used as the most effective medicine in nasal polyposis. Although oral corticosteroids are one of the frequently used treatments in the management of chronic rhinosinusitis with nasal polyps (CRSwNP), there is lack of effective means of predicting corticosteroid sensitivity in those patients. It was reported that the overall sensitivity rates of corticosteroid therapy to nasal polyps( NP) were only between 53.8% and 80%.. Many reports stated that serum and tissue interleukeine 25 (IL 25) and serum and tissue eosinophalia are good predictors to the response of CRSwNP to oral corticosteroids.

Interleukeine 25(IL-25), an important epithelial-derived proinflammatory cytokine, plays various roles in different inflammatory and allergic diseases, such as asthma and atopic dermatitis .

Hong et al demonstrated that the levels of IL-25 in NP tissues and in serum, as well as the NP endoscopic scores, were significantly elevated in the corticosteroid-sensitive patients compared with the non-sensitive ones. In general, eosinophilic NPs are pharmacologically glucocorticoid responsive, but non-eosinophilic or neutrophilic CRSwNP is frequently resistant to steroid treatment.

Inclusion Criteria:

• clinical diagnosis of chronic rhinosinusitis with nasal polyps

Exclusion Criteria:

• 1-Patients who had taken any steroid , antihistamine or other immune-modulating medications within the past 4 weeks

  2- previous nasal and sinus surgery.

  3-Allergic Fungal rhinosinusitis.

  4-Unilateral rhinosinusitis.

  5- Antrochoanal polyps or cystic fibrosis.