Characteristics of patient are summarized in Table 1 . CF patients had more expiratory airflow obstruction, as mea-sured by the FEV 1 % predicted, although not significantly different from PCD patients, and were more likely to be colonized with Pseudomonas aeruginosa and Staphylococcus aureus. In some CF patients, more than one bacterial strain colonized the same patient. The acute and stable groups of CF patients were well differentiated on the basis of decrease in FEV 1 as compared with the best one in the last year (ΔFEV 1 ), serum CRP, and clinical score ( Table 1) .