A 22-year-old woman came into my office complaining of increasing fatigue that had been worsening over the last six months. On top of that, dull abdominal pain and bloating were causing her considerable discomfort.

Her previous medical visits resulted in a barrage of appropriate blood work that showed mild anemia with low iron counts and mild inflammation of the liver – puzzling in a young woman who rarely drank alcohol and was otherwise very healthy. Breath testing ruled out the presence of bacteria that might have caused inflammation in the stomach or small intestine.

An ultrasound and CT scan of her abdomen were of no help in finding a diagnosis. Eventually, she was thought to have heartburn and started on acid blocking medications. When her symptoms didn’t improve, she was diagnosed with functional dyspepsia – which is simply the medical term for a condition that causes discomfort in the upper belly. In other words, it wasn’t helpful to the patient.

Stumped, her clinicians referred her to a gastroenterologist, which is how I met her.

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When I pressed gently on my patient’s upper abdomen, I could see she was in pain. I also noticed a red, blistering rash on her knees she hadn’t thought to mention.

But it turned out to be an important clue that, along with her abdominal symptoms, prompted me to send her for more testing.

Solution

As I suspected she would, my patient tested positive for antibodies that attack tissue transglutaminase, an important enzyme that helps the body heal.

An endoscopy with biopsies confirmed that my patient had celiac disease. When she stopped eating anything containing gluten, her symptoms and blood counts improved significantly.

Celiac disease is an autoimmune reaction to foods containing gluten, such as wheat, barley, rye, and bulgur. To judge from all the gluten-free products on the market, you might think celiac is a very common condition. In reality, an estimated 1% of the population has true celiac disease. Others may have a wheat allergy or a less-severe sensitivity to gluten, or just may prefer a gluten-free diet.

Years and years of data have shown us that patients with celiac disease should never eat gluten. If they do, the short-term results can include fatigue, abdominal pain, weight loss, and particularly foul-smelling diarrhea. Longer term, it can cause vitamin deficiencies and osteoporosis.

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It’s important to get a medical diagnosis, rather than relying on the internet to decide you have celiac disease. Keep a food journal including what you’ve eaten and how you react to it with the help of such phone applications as MySymptoms Food Diary & Symptom Tracker. If gluten appears to be a problem, see your doctor.

If your celiac tests are positive, go gluten free. It is a medical necessity. Keep in mind that not all products and restaurant meals that claim to be gluten-free are truly gluten-free.

If your celiac tests are negative, try a gluten-free diet and monitor symptoms. If you feel better, you might have non-celiac sensitivity or food allergies. If there is no difference in symptoms, introduce gluten back to your diet.

Keerthi Shah is a gastrointestinal fellow at Temple University. Follow her on Twitter at @KeerthiShahDO or Instagram at @Digestivedoc.