Review Question - QID 212502

A 37-year-old man presents to his primary care physician with a chief complaint of diarrhea. The patient states that his symptoms have worsened recently. He works as a farmer and is dressed in tattered and old denim. He lives alone, and this is the first time he has come to town in years. The patient’s diet is mostly dairy products and some meat products. He denies any systemic symptoms and states that diarrhea tends to occur right after a meal. He also claims that at times he struggles to fall asleep, and sometimes he feels he lacks energy. The patient is instructed to avoid consuming dairy products for a week and to return with a report of his symptoms. As you set up the return appointment with this patient you notice that he is rather emotionless. He also states that he lacks anybody that he can list as an emergency contact so he leaves that section of his medical forms blank. What is the most likely diagnosis?