Review Question - QID 210827

A 27-year-old man presents to the emergency department with general weakness and fatigue. He states that he has not felt well for several days and can't take care of himself anymore due to fatigue. The patient has a past medical history of IV drug abuse, alcohol abuse, and multiple minor traumas associated with intoxication. His temperature is 104°F (40°C), blood pressure is 127/68 mmHg, pulse is 120/min, respirations are 19/min, and oxygen saturation is 98% on room air. A murmur is heard on cardiac exam. The patient is treated appropriately and transferred to the inpatient floor and recovers over the next several days. The patient has been unable to eat solids, though he has been drinking large amounts of juice. On day 5 of his stay, the patient states he feels much better. He is no longer febrile. His only concern is profuse and watery diarrhea and severe abdominal pain which he has been experiencing since yesterday. The patient is started on IV fluids and given oral fluid replacement as well. Which of the following is associated with the most likely underlying diagnosis?