Anorexia nervosa

Disease Description (Causes and Symptoms)

• Definition summary: A chronic autoimmune disease (celiac disease) in which an immune response to gluten (a protein contained in wheat, barley, rye, etc.) damages the villi of the small-intestinal mucosa, reducing nutrient absorption.
• Causes/Pathophysiology:
  • Interaction between genetic predisposition (mainly HLA‑DQ2 or HLA‑DQ8) and gluten exposure.
  • When peptides in gluten (e.g., gliadin) are modified by tissue transglutaminase (tTG), the immune system recognizes them and causes CD4+ T-cell-mediated inflammation, resulting in villous atrophy and mucosal damage.
  • Environmental factors such as infection, surgery, pregnancy, and stress may trigger disease onset.
• Main symptoms:
  • Gastrointestinal: Chronic diarrhea (steatorrhea), abdominal bloating and pain, weight loss, and signs of malnutrition.
  • Systemic/other: Iron- or folate-deficiency anemia, growth delay (in children), infertility and menstrual abnormalities, fatigue, skin rash (e.g., dermatitis herpetiformis), neurological symptoms (numbness, tingling, ataxia), oral ulcers, etc.
  • Symptoms vary from mild to severe, and some people may be asymptomatic or have atypical symptoms (non-gastrointestinal symptoms).

Treatment Methods

• First-line treatment: A lifelong strict gluten-free diet (GFD).
  • Avoid wheat, barley, rye (and, in the case of oats, check for cross-contamination) and foods containing ingredients derived from them.
  • Designing a balanced diet and receiving label-reading education through a registered dietitian (in consultation with a gastroenterologist) are recommended.
• Supportive treatment:
  • Replenishing deficiencies: Supplement iron, folate, vitamin B12, vitamin D, calcium, etc., according to the deficiencies present.
  • If bone density is reduced, treat osteoporosis (vitamin D and calcium, and osteoporosis medication if necessary).
• Drug treatment:
  • If symptoms do not improve after gluten elimination or if there is severe inflammation (or refractory celiac disease), the use of steroids (e.g., budesonide) or immunomodulators (such as azathioprine) may be considered. Diagnosis and treatment by a specialist are required.
  • Rare refractory or recurrent forms (such as T-cell variants related to recurrent villous enteropathy) may require additional immunotherapy or anticancer treatment at a specialized center.
• Follow-up:
  • Monitor treatment response with serological tests (anti‑tTG, DGP, etc.), usually every 6–12 months.
  • Symptoms may begin to improve within several weeks, but mucosal recovery may take several months to several years.
• Precautions (related to treatment):
  • If gluten is eliminated before diagnosis, serum test and biopsy results may be falsely negative. Therefore, if you plan to undergo testing, you should continue eating foods containing gluten before the tests.
  • Be aware of hidden gluten in over-the-counter medications, restaurant meals, and processed foods.
  • Pure oats are generally allowed, but it is necessary to check whether the product has been cross-contaminated.
  • Smoking and excessive alcohol consumption may increase the risk of complications, so consultation is recommended.

Checklist Before an Outpatient Visit (Including Sample Questions)

• Items/documents to prepare:
  • A list of medications and supplements currently or recently taken (especially vitamins and iron supplements).
  • Previous blood test results (especially hemoglobin, iron/ferritin, vitamin D, and B12), and any previous gastrointestinal endoscopy (biopsy) results or medical records.
  • Family history (especially celiac disease, type 1 diabetes, or autoimmune diseases in first-degree relatives).
  • Symptom diary: The timing and changes in weight changes, diarrhea (color, amount, and duration), abdominal bloating, rash, and neurological symptoms.
  • Dietary status: Whether you have consumed gluten in recent weeks (important before testing).
• Information helpful for the doctor to know during the outpatient visit:
  • When symptoms began and how they have progressed (whether they began in childhood or adulthood).
  • Whether you suspect a connection between symptoms and gluten consumption.
  • Any history of allergies or autoimmune diseases.
• Sample questions (for showing to the doctor):
  • "How long do I need to continue eating gluten for the tests?"
  • "Which tests are needed: blood tests, endoscopy, or biopsy?"

General Sample Questions to Ask the Doctor

• What are the side effects and interactions of this medication (or supplement)?
• What is the prognosis? When can I expect mucosal recovery and symptom improvement after treatment?
• Are there any particular precautions I should take regarding lifestyle factors (diet, exercise, pregnancy plans, etc.)?
• How often are follow-up tests (such as blood tests and bone density tests) recommended?

Disease-Specific Sample Questions

• 1. "How should my anti‑tTG (or EMA) level and biopsy results (Marsh classification) be interpreted, and to what extent is treatment necessary?"
• 2. "How many weeks does it take for symptoms to improve after eliminating gluten? How can mucosal recovery be confirmed (which tests should be performed and when)?"

Summary of Additional Recommendations:

• Before diagnosis, never stop eating gluten on your own; maintain your usual diet before testing (serology and endoscopic biopsy).
• After diagnosis, consult a registered dietitian and receive regular monitoring of bone density, vitamins, and anemia.
• If symptoms persist or new symptoms develop, consult a gastroenterologist for reevaluation.