Q. A 45-year-old man with a history of hypertension and diabetes, presents to the emergency department with complaints of nausea, vomiting, and diffuse abdominal pain. Physical examination reveals hypotension and oliguria. His laboratory results show an increase in creatinine levels. Imaging studies reveal diffuse parenchymal damage. The patient's medical history reveals recent episodes of diarrhea and vomiting. Urine analysis shows the presence of muddy brown casts. What is the most likely diagnosis in this patient?