Correlation of Chest Radiograph Pattern with Genotype, Age, and Gender in Adult Cystic Fibrosis: a Single-center Study

Introduction: Cystic fibrosis (CF) is a common lethal genetic disorder. The aim of this study was to determine the common chest radiograph (CXR) patterns in adult CF, and correlate disease distribution on CXRs with genotype, age, and gender.

Methods: One hundred nine CF patients treated at Baylor Adult Cystic Fibrosis Center were identified. The intake CXR was reviewed and characterized as diffuse bilateral (DB), unilateral, upper lobe (UL), and lower lobe (LL) disease, or relatively normal. Lack of intake CXR, and/or genotype excluded 41 patients from analysis.

Results: Of 68 patients, 38 were homozygous for DeltaF508 and 30 were heterozygous. Mean age of the population was 30 +/- 8 years (+/- SD) [range, 18 to 48 years]. The most common CXR pattern was DB; 62% had DB, 28% had UL, and 7% had LL predominance. This is in contrast to the UL-predominant CXR pattern commonly described in the pediatric population. In 18 DB patients, archived pediatric films were available, and the average patient age was 15.7 years. DB pattern was present in 16 of 18 CXRs that antedated adult intake CXRs by an average of 12.7 years. Homozygous DeltaF508 genotype was identified in 56% of patients and did not distinguish radiologic phenotypes. There was no association between radiograph pattern and identified infecting/colonizing organisms and percentage of predicted FEV(1).

Conclusions: CF has commonly been reported as an UL disease. However, in this study of adult patients, the common pattern observed was DB. A small subgroup analysis suggests that DB disease was not a pattern of disease evolution but may be present from disease onset.