Cystic fibrosis: unenhanced CT description of the appendix in asymptomatic adults

The purpose of this study was to describe the unenhanced CT appearance of the appendix in adults with cystic fibrosis.

Among adults with cystic fibrosis undergoing follow-up at our hospital, 71 patients (35 women, 36 men; mean age, 33 years; range, 18-59 years) without a history of appendectomy or current abdominal pain were prospectively included in this study and underwent unenhanced abdominopelvic MDCT. Two readers coded visualization of the appendix, measured the diameter of the appendix, and described the attenuation of its contents in relation to the intestinal wall. They also coded the presence of colonic wall redundancy, pancreatic fatty replacement, and cirrhosis. Lung transplant status and CFTR gene mutations were recorded. Analysis of variance, linear regression analysis, Student t test, and Pearson test were used.

The appendix was detected in all patients. The mean diameter was recorded as 10.6 ± 3.5 mm. The mean diameter was larger when the appendix contained hyperattenuating material (p = 0.001). There was no association between diameter and the other coded CT findings (p = 0.076-0.466), transplant status (p = 0.788), or CFTR mutation (p = 0.078). In 75% of the patients, the appendix contained hyperattenuating material with a higher proportion in homozygous ΔF508 mutation (p = 0.029) without any significant effect of the other CT features (p = 0.056-0.392), or transplant status (p = 1.000).

The appendix is larger in adults with cystic fibrosis than in those without it and appears hyperattenuating at unenhanced CT in 75% of patients, more commonly in those with ΔF508 homozygous mutation.