Case Study of the Week: Rhabdomyolysis

Right now, I am training for a marathon spending my Saturday mornings running 20ish miles.    Naturally, I am beginning to acquire some aches and pains.  A twinge behind my left knee and a pull in my right achilles aren't painful, just a bit uncomfortable.  But what about when working out goes really haywire and muscle tissue begins to break down too rapidly?  

Rhabdomyolysis is one of my favorite conditions to diagnose and treat.  It is a condition where muscle tissue breaks down rapidly releasing products of damaged muscle cells, like myoglobin, into the bloodstream.  These muscle products are harmful to the kidney and can lead to renal failure.  

The classic triad of symptoms in rhabdomyolysis includes myalgia, generalized weakness and dark urine.  In reality, patients may present with a variety of symptoms including nausea, vomiting and fever.  Causes of rhabdomyolysis vary widely including illicit drug use, heatstroke, infection, trauma and alcohol use.  Because of it's potentially serious nature, medical providers must be familiar with diagnosis and treatment of rhabdomyolysis. 

Case Presentation

A 42 year-old male patient presents to the emergency department stating he has severe muscle aches over his entire body.  He reports he has been out in the heat all day working as a landscaper.  His job today was particularly taxing.  While he did drink some water throughout the day, he is concerned he may be dehydrated.  The patient reports dark urine the color of "Coca-Cola".  He has no prior medical history.

On exam, you note the patient appears to be uncomfortable.  He has diffuse muscle tenderness in his back, chest and legs.  Although his muscles are tender, they are not swollen and pulses are intact so you do not suspect compartment syndrome.  The patient is tachycardic with a pulse of 114.  Based on this patient's history and physical exam you suspect rhabdomyolysis and order a complete blood count, serum chemistries including kidney function and electrolytes and CK to confirm your diagnosis.

Management and Outcome

Treatment of rhabdomyolysis is largely supportive.  Patients should be rehydrated with IV fluids and urine output recorded.  Giving fluids corrects/ prevents acute renal failure.  The cause of rhabdomyolysis must be identified and corrected if possible.  Some patients with rhabdomyolysis develop electrolyte imbalances which must be monitored and corrected.  In patients with electrolyte imbalances, especially hyperkalemia, an ECG should be obtained.  Monitor CK levels as this shows resolution of rhabdomyolysis.  Once patients are hydrated and electrolytes and renal function have returned to normal, they may be released from the hospital for follow-up on an outpatient basis.  

While most patients treated for rhabdomyolysis have good outcomes, the condition must be promptly diagnosed and treated to prevent long-term kidney damage.  Patients with a CK level 2-3 times normal should be suspected of having the condition and IV fluid rehydration started immediately.  30-40% of patients with rhabdomyolysis develop acute renal failure.  Typically, this resolves with rehydration but in severe cases, such as those with renal failure and persistent hyperkalemia, dialysis may be required.  


Causes of rhabdomyolysis vary widely so providers must keep it in mind when diagnosing causes of muscle pain.  Popular workouts P90X and CrossFit, for example, have caused participants to develop the condition.  Simple lab tests are the key to diagnosing rhabdomyolysis.  Once the condition is diagnosed, it must be treated promptly to prevent complications.