Background: CD14 is known as a receptor for bacterial LPS (Lipopolysaccharides) and is followed by inflammatory reactions. This receptor on macrophage surface has a major role for recognition and clearance was happen without inflammatory reaction. Prolonged exposure to microbial products decreases the risk of allergic reactions. This is related to high level of CD14 in blood cells. Although the causes of nasal polyposis is not obviously determined but allergy is a potential risk factor for nasal polyposis. CD14 is in 5q31 chromosomal position and CD14 variants have association with asthma. We try to assay association between CD14 polymorphism and nasal polyposis and severity of this disease.

Methods: We had 106 patients with nasal polyps with mean age 41 y old in case group and 87 with mean age 36.7 in control group. We obtained 3 ml whole blood from each patient and then extract DNA by PCR-RFLP method and determined variant genotypes of CD14. Although there is no previous study in this field, the results of this pilot study shown in more detailed below.

Results: There is significant relationship between C allele (CC + CT) in comparison with TT (p= 0.03, odds ratio= 1.87, CI 95% (0.99- 3.55)) and nasal polyposis. Further-more another significant relationship had been shown between asthmatic patients and C allele (CC) in comparison with (CT + TT). (p= 0.01, odds ratio= 3.8, CI (0.99- 13.9). In asthmatic patients with C allele of CD14 incidence of nasal polyposis increased.

Conclusion: Based on the results of this study, C allele of CD14 could play a role in nasal polyposis.