BALTIMORE -- If you suffer from chronic fatigue, irritable bowel syndrome or you are often plagued by gas or diarrhea, you may actually have celiac disease. It's a common, but underdiagnosed genetic condition of the small intestine.

Kathleen Weber said she has always been gassy.

"It's a big thing in the family, it's embarrassingly bad," Weber said.

And she has always had diarrhea.

"I had to carry Immodium, Pepto Bismol. I would have Lactaid if I had dairy, use Beano if I had a salad," Weber said.

Two years ago, a bone scan showed she was on the edge of having osteoporosis. So Weber increased her calcium intake and started taking a prescription bone-building medicine.

But she thought it didn’t work.

"The next month, I had blood work, which showed my calcium levels were lower than the month before. That didn't make sense," Weber said.

But it did work. Weber actually had celiac disease passing through her. Celiac disease is often thought of as a children's ailment, which is why doctors missed it in adults for a long time.

"Now, we're seeing the classic celiac disease was just the tip of the iceberg. We're seeing celiac in people 70 to 80 years old," Dr. Michael Cox, of Baltimore's Mercy Medical Center, said.

The classic symptoms for celiac disease include diarrhea, short stature, anemia and weight loss. Doctors are now realizing liver problems, thyroid problems, gas and bloating, skin lesions and chronic fatigue are often related to celiac disease.

"All sorts of common symptoms, but we never thought about celiac disease. Now we are," Cox said.

Weber immediately went on the celiac, gluten-free diet, which prohibits any ingredients with wheat, oats, rye or barley. And she feels great -- all symptoms are gone.

Cox said people diagnosed with chronic fatigue syndrome or irritable bowel syndrome should also be tested for celiac disease.

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