A 26-year-old man is involved in a motor vehicle accident and sustains acute blood loss. He is hypotensive for several hours before paramedical personnel arrive. They stabilize the bleeding and transport him to a hospital, where he receives a transfusion of 3 units of packed RBCs. Over the next week, the serum urea nitrogen level increases to 48md/dL, the serum creatinine level increases to 5mg/dL, and the urine output decreases. He undergoes hemodialysis for the next 2 weeks and then develops marked polyuria, with urine output of 2 to 3L per day. His recovery is complicated by bronchopneumonia, but renal function gradually returns to normal. Which of the following histological features best characterizes the patient’s transient renal disease?