Rhabdomyolysis in Children

Rhabdomyolysis is a rare but serious condition that causes excessive muscle breakdown which may lead to kidney injury or failure.   

Rhabdomyolysis in children can be triggered by infections, exercise, muscle injury, and in rare cases some medications or genetic conditions.  

What happens? 

• • The excess breakdown of muscle fibers releases a protein called myoglobin into the blood stream.  
  • Small amounts of myoglobin breakdown from normal muscle use every day.  These are filtered out of the blood stream through the kidneys.   
  • The dangerous effect of rhabdomyolysis occurs when large amounts of myoglobin are released quickly. 
  • The extra protein can overwhelm and potentially damage the kidneys.  This condition requires prompt and appropriate treatment to prevent serious or life-threatening kidney injury or failure.  

Causes of Rhabdomyolysis in Children:   

• • Infection:   
    • Infections are the most frequent cause of rhabdomyolysis in children.   
    • Influenza, Ebstein Barr Virus (which causes Mononucleosis) and other flu-like viruses are the most common illnesses that may lead to rhabdomyolysis in children.   
    • Rhabdo has also been reported rarely in association with bacterial infections such as strep throat. 

• • Exercise, muscle strain, or injury:  
    This is the most common cause of rhabdomyolysis in adults, but less so in children. When rhabdomyolysis from exercise (or injury) does occur in children, it is often a result of a rapid increase in activity after a period or inactivity.  For example, if a teenager goes all Winter without exercising and then starts an aggressive training routine for a new sports season in the Spring. 
    • Dehydration, heat, high humidity, underlying medical conditions (such as sickle cell), and some medications increase the risk of rhabdomyolysis developing from exercise.  
    • Children should never exercise or play sports while sick with fever, body aches, or flu-like symptoms for this reason. 

    Crush injuries may also lead to rhabdomyolysis and should always be evaluated by a medical professional. 

  • Medications: Some pediatric medications that have been associated with rhabdomyolysis include: 
    • Neuroleptic and psychiatric medications such as risperidone, quietapine, olanzapine, arpiprazole and lithium.  
    • Isotretenoin acne medications such as Accutane 
    • Corticosteroids  
    • Anesthesia

• • Genetic Conditions: Some genetic and inheritable conditions may increase the chances of a child developing rhabdomyolysis. 

          Signs of these may include:   

• • • Family history of rhabdo 
    • Multiple episodes in the same child 
    • Rhabdomyolysis with no other triggering causes

Signs and Symptoms: Severe body aches (also called myalgia) during a flu-like or febrile illness may be the first sign of rhabdomyolysis in your child.  

Other signs to watch for include:

• • Body aches, with muscle tenderness, that appear much more severe than expected. 
  • Muscle weakness 
  • Pain and tenderness that limits motion of the joints such as the neck, arms, or legs. 
  • Swelling of the tender or painful muscles (especially with no injury beforehand) 
  • Difficulty walking due to pain or weakness. 
  • Brown or tea colored urine 
  • Decrease in urine output. 

What to do: 

• For mild body aches and flu-like symptoms push fluids and lots of rest.  Avoid exercise and sports until fully recovered or cleared by the doctor.  
• If your child has any signs and symptoms of rhabdomyolysis seek evaluation as soon as possible. 
• For muscle weakness, brown/tea colored urine, decreased urine output or no urine in more than 6 hours with any other of the above symptoms, seek immediate medical attention. 

Diagnosis and Treatment:  

• If your child’s doctor is concerned about rhabdomyolysis, they may order blood work to evaluate the degree of muscle breakdown and to check for electrolyte imbalance and kidney function.  
• Treatment often involves a hospital stay and includes rest, Intravenous (IV) fluids, and monitoring kidney function until symptoms resolve.