Crohn's - the silent disease

Watching 22-year-old Molly Shannon race uphill, it's hard to imagine there are times when she can't get out of bed.

"When I am able to work out it makes me feel like I'm beating it because I'm overcoming the pain or fatigue I might have another day," she says.

Molly had a bout of intense stomach pain when she was seven, ulcers that were visible in the back of her throat extended throughout her gastrointestinal tract. She had Crohn's Disease.

An estimated 780,000 Americans have Crohn's.

Most of them are diagnosed between the ages of 15 and 35.

And unlike other inflammatory bowel diseases, Crohn's symptoms can be vague, ranging from diarrhea, to constipation and abdominal cramps.

"Many patients don't present with the disease until they have a complication, a perforation, or a stricture causing a blockage," says Dr. Marc Schwartz, a gastroenterologist.

Molly's inflammation required two surgeries.

"My first surgery - they took out five inches of my small intestine. Then while they were in there they found another five inches of stricture in my colon," she says.

During the second surgery, doctors removed another four inches. Right now, medication controls Molly's symptoms. Her experience with Crohn's sparked an interest in medicine. She's now a nurse, working with other gastroenterology patients.

She's helping spread the word about the so-called 'silent disease'.

Researchers are still not sure what causes the condition but say genetics and a trigger like a viral infection may play a role.