Prevalence and histopathology of chronic polypoid sinusitis in pediatric patients with cystic fibrosis.

BACKGROUND: Chronic sinusitis is almost invariably a feature of cystic fibrosis. However, data on the endoscopically confirmed prevalence of chronic polypoid sinusitis (CPS) and its histological features are limited.

METHODS: Single centre prospective observational study. Unselected pediatric CF patients (n=81; ≤ 18 years) were endoscopically assessed for the prevalence of CPS. Sixteen of these underwent sinus surgery. The surgically obtained sinus specimens were compared to sinus specimen of non-CF-patients undergoing sinus surgery (n=61), using conventional histology and immunohistochemistry.

RESULTS: The prevalence of endoscopically confirmed CPS increased with age from 19% in infants younger than six years reaching 45% in adolescents. In CF patients, histology typically showed dilated glandular ducts and a predominance of mucous glands. The number of plasma cells and mast cells but not of eosinophils was significantly elevated compared to non-CF patients.

CONCLUSION: Prevalence of CPS in pediatric CF patients increases with age. Our findings indicate that chronic bacterial infection rather than allergic mechanisms may forward this pathology.