Relationship between functional and X-ray alterations in patients with cystic fibrosis

background: cystic fibrosis (cf) is a disease marked by airway inflammation and airflow obstruction, resulting in air trapping in the lungs. objective: to assess the associations between airflow limitation, pulmonary volume and x-ray findings in patients with cystic fibrosis. method: a cross-sectional retrospective study. review of spirometric, plethysmographic, and chest x-ray findings of outpatients (age 3 16 years). the airflow findings were classified as within normal limits or as airflow obstruction: mild, moderate or severe obstructive alteration. results: a total of 23 patients (15 male and eight female; mean age, 21 ± 5.9 years) were studied. six of them were within normal limits, four had a mild, five had a moderate, and eight had a severe obstructive alteration. there was an association between airflow limitation and the increase of residual volume (p = 0.006) and also with the brasfield score (p = 0.001), but not with the total lung capacity (p = 0.33). there was a correlation between residual volume and brasfield score (r = 0,73, p = 0,002), but not with the total pulmonary capacity. moreover, according to x-ray criteria, the air trapping was correlated only with the residual volume (p = 0.006). conclusion: in patients with cystic fibrosis (age 3 16 years), the progressive airflow limitation is accompanied by an increase in residual volume, while the total pulmonary capacity remains normal or tends to decrease. the x-ray score was associated with airflow limitation and residual volume, but not with total lung capacity.