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

RESUMO

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 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 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.