A 62-year-old woman was referred to Gastroenterology appointment due to severe iron deficiency anemia (5.9 g/dL), complaining of asthenia and requiring blood transfusion. The patient denied blood loss. Initial blood test showed a severe iron deficiency, with ferritin of 5ng/mL and transferrin saturation of 2.7%. Folic acid and vitamin B12 were normal. Upper gastroscopy and colonoscopy didn't show any lesions. Abdominopelvic CT and capsule endoscopy were, also, normal.