Eosinophilic cationic protein as a marker of nasal inflammation in patients with cystic fibrosis.

OBJECTIVES: Evaluation was made of eosinophilic cationic protein (ECP) in nasal secretion for measuring the degree of nasal inflammation and monitoring response to therapy in cystic fibrosis (CF) patients with chronic rhinosinusitis. Symptoms and findings in regard to ECP levels before and after treatment were described. STUDY DESIGN: Study was prospective, with 21 CF patients aged 4 to 19 years; 20 healthy volunteers served as controls. Collection of nasal secretion by a sponge was performed, and blood samples were obtained for serum. Cystic fibrosis (CF) patients were classified according to nasal symptoms and findings. METHODS: ECP was measured by fluoroimmunoassay. Age, sex, nasal symptoms, and endoscopic and histological findings were obtained, and examinations were conducted before and after treatment; recurrences were recorded. RESULTS: In CF patients with chronic nasal inflammation, increased nasal levels of ECP were detected when compared with asymptomatic CF patients or healthy nonatopic subjects. ECP concentrations were strongly related to the extent of nasal disease; patients with nasal polyps had higher levels than those without. Checked at 1 and 4 months after treatment, ECP levels declined with regression of symptoms, and in patients with exacerbation of nasal disease, ECP levels rose. CONCLUSIONS: According to our study, there is a relationship between levels of ECP in nasal secretions and the degrees of nasal inflammation. In addition, the measurement of ECP could be useful in monitoring nasal disease in CF patients.