A child, adolescent or adult with cystic fibrosis is at risk for the distal intestinal obstructive syndrome (DIOS).


Synonym: meconium ileus equivalent


Pathophysiology: bowel contents become inspissated because of pancreatic insufficiency and reduced intestinal water content


Clinical features:

(1) partial or complete bowel obstruction

(2) presence of a tenacious mucofeculent plug in the terminal ileum, cecum and right colon

(3) right lower quadrant pain with a palpable mass


Imaging studies:

(1) dilated ileum with collapsed distal colon

(2) ultrasonography identifies the plug


Medical management:

(1) rehydration if dehydrated

(2) oral 2-4% N-acetylcysteine (a mucolytic agent)

(3) oral pancreatic enzyme supplementation

(4) oral lactulose, senna or other laxative

(5) oral agent to help mobilized stool

(5a) diatrizoate meglumine and diatrizoate sodium

(5b) osmotically active hypertonic agent

(5c) oral polyethylene glycol

(6) analgesic for pain control

(7) colonoscopy to instill diatrizoate meglumine and diatrizoate sodium


Surgery is generally discouraged because of the risk of complications but it may be needed if there is bowel ischemia or if medical management fails.


Surgical management:

(1) open disimpaction

(2) appendectomy with appendicostomy tube placed for bowel irrigation, followed by open disimpaction

(3) enterostomy with bowel irrigation

(4) bowel resection as last resort


Differential diagnosis:

(1) acute pancreatitis


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