Review Question - QID 214216

A 45-year-old woman presents to the clinic for an annual well check. She complains of a burning epigastric pain that is worse after food intake for the past 4 months. Over-the-counter omeprazole partially alleviates the pain. In addition, the patient endorses constipation and vague abdominal pain over the past several weeks. She eats a well-balanced diet with fruits and vegetables and exercises 2-3 times a week. Family history is significant for a pituitary tumor in her mother and heart attack in her father when he was 67 years old. Which of the following laboratory abnormalities is most likely in this patient?