Background: Epithelial hyperplasia and mucosal infiltration of leukocytes are common features of chronic rhinosinusitis. The epithelium can produce chemoattractant cytokines that may contribute to leukocyte infiltration in rhinosinusitis.
Objective: We sought to determine whether mucosal IL-8 gene expression is increased in chronic rhinosinusitis and to relate IL-8 gene expression to disease severity.
Methods: We used both a noncompetitive and a quantitative, competitive reverse transcription-polymerase chain reaction to examine IL-8 gene expression in samples of sinus mucosal tissue obtained during surgery from 22 patients with chronic rhinosinusitis and 9 normal control subjects. IL-8 gene expression was related to disease severity assessed by sinus computed tomography (CT) scores and to symptom scores assessed by means of a questionnaire.
Results: Sinus mucosal IL-8 gene expression was not detected in any of the control subjects but was present in 12 of 22 (55%) patients with rhinosinusitis. Sinus CT scores and symptom scores were both significantly higher in patients with positive mucosal IL-8 gene expression than in subjects with no detectable IL-8 gene expression. Positive IL-8 gene expression was not predicted by history of prior surgery nor by atopic or asthmatic status. In 9 subjects with positive IL-8 gene expression, levels of mRNA expression, assessed by competitive reverse transcription-polymerase chain reaction, correlated significantly (rho = 0.72, P <.05) with sinus CT scores.
Conclusion: Sinus mucosal expression of the gene for IL-8 is increased in patients with chronic rhinosinusitis, and the level of IL-8 gene expression correlates with disease severity.