A 20-year-old woman is brought to the emergency department because of severe muscle soreness, nausea, and darkened urine for 2 days. The patient is on the college track team and has been training intensively for an upcoming event. One month ago, she had a urinary tract infection and was treated with nitrofurantoin. She appears healthy. Her temperature is 37.0°C (98.6°F), pulse is 64/min, and blood pressure is 110/70 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. There is diffuse muscle tenderness over the arms, legs, and back. Laboratory results are as follows: Which of the following is the most likely cause of this patient's kidney injury?

Question

A 20-year-old woman is brought to the emergency department because of severe muscle soreness, nausea, and darkened urine for 2 days. The patient is on the college track team and has been training intensively for an upcoming event. One month ago, she had a urinary tract infection and was treated with nitrofurantoin. She appears healthy. Her temperature is 37.0°C (98.6°F), pulse is 64/min, and blood pressure is 110/70 mm Hg. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. There is diffuse muscle tenderness over the arms, legs, and back.   Laboratory results are as follows:  Which of the following is the most likely cause of this patient's kidney injury?

Quizplus · Accepted Answer

Eductional Objective: Rhabdomyolysis is characterized by the release of intracellular muscle contents (eg, myoglobin, electrolytes) due to myocyte injury; it is common with crush injuries, seizures, or drug use (eg, statins).  Heme pigment (released from myoglobin after degradation in the kidney) is toxic to tubular cells and can cause acute tubular necrosis.  Positive blood on urine dipstick in the absence of red blood cells on microscopic urinalysis suggests myoglobinuria.

A 20-Year-Old Woman Is Brought to the Emergency Department Because