Occult appendiceal abscess complicating cystic fibrosis.

Three case histories illustrate the diagnostic dilemma encountered whenever a patient with 
CF who is receiving antibiotics is evaluated for abdominal pain. Although 
acute appendicitis with perforation and abscess formation is not a common 
complication of CF, it occurs more frequently than is generally appreciated. 
The large number of abdominal situations in CF which can cause 
pain confused with but not typical of acute appendicitis. The true 
underlying condition is further masked by the concurrent use of antibiotics 
for pulmonary infection. A higher index of suspicion is needed to 
rule out acute appendicitis in a patient with cystic fibrosis and 
abdominal pain. A greater awaremess of the possibility of occult appendiceal 
abscess may help to avoid this complication. 