Contrast enemas in cystic fibrosis: implications of appendiceal nonfilling

In patients with abdominal pain and suspected appendicitis, contrast examinations of the colon suggest appendicitis when there is lack of filling of the appendix, and a cecal filling defect. Complete opacification of the appendiceal lumen tends to exclude this diagnosis. In cystic fibrosis, however, the incidence and importance of these findings are unknown. The colon examinations of 29 cystic fibrosis patients who had surgery or long-term follow-up were reviewed. Some degree of appendiceal filling occurred in seven patients. Five had normal appendices of laparotomy; two were discharged. The appendices of the other 22 patients failed to fill and there were 10 cecal filling defects. Appendicitis was shown by laparotomy in only four of these patients. Although appendiceal filling indicated lack of appendicitis as in other patients, lack of visualization of the appendix is not a reliable sign of appendicitis in cystic fibrosis. Histologic studies indicate that nonfilling is frequently related to mucus plugging of the lumen.