Proinflammatory cytokine levels in nasal fluid as indicators of severity of nasal polyposis.

The aim of this prospective study was to evaluate whether cytokine levels in nasal secretions may be clinical parameters of severity of nasal polyposis. Forty nasal polyp patients (20 asthmatic and 20 nonasthmatic) requiring surgical treatment were included. Nasal secretion samples were collected from nasal cavities of all 40 subjects. The levels of T-helper type 1 (Th1) proinflammatory cytokines IL-2, IL-12, IFN-gamma, IL-1beta, TNF-alpha and TNF-beta, Th2 cytokines IL-4, IL-5 and IL-6, antiinflammatory cytokine IL-10 and chemokine IL-8 were measured using flow cytometric method. Each of the 40 patients was staged clinically according to global nasal symptom score, endoscopic score, and Lund-Mackay computed tomography (CT) score. Eosinophils were counted in hematoxylin-eosin stained sections of all nasal polyp samples. The concentrations of Th2 proinflammatory cytokines IL-5 and IL-6 were significantly higher (P < 0.05 and P < 0.01, respectively) in patients with nasal polyposis and asthma compared with nasal polyp patients without asthma. Positive correlations were observed between IL-2 concentration in nasal secretions and nasal symptom score, endoscopic score, and Lund-Mackay score only in nasal polyp patients without asthma. We also found positive correlation between Lund-Mackay score and the levels of IL-8, IL-4, and IL-1beta in nonasthmatic patients. A positive correlation between IL-5 levels in nasal fluid and endoscopic score was found only in asthmatic patients. Eosinophil counts were higher in asthmatic patients' polyps compared with nonasthmatic ones, but without statistical significance. Nasal polyposis in asthmatic patients has different immunological patterns compared to those without asthma. The concentrations of cytokines measured in nasal fluid were not sensitive enough to be universal criteria to determine the severity of all forms of nasal polyposis.