Rhabdomyolysis is the breakdown of muscle fibers resulting in the release of muscle fiber contents (myoglobin) into the bloodstream. Some of these are harmful to the kidney and frequently result in kidney damage.
When muscle is damaged, a protein pigment called myoglobin is released into the bloodstream and filtered out of the body by the kidneys. Myoglobin breaks down into potentially harmful compounds. It may block the structures of the kidney, causing damage such as acute tubular necrosis or kidney failure.
Dead muscle tissue may cause a large amount of fluid to move from the blood into the muscle, reducing the fluid volume of the body and leading to shock and reduced blood flow to the kidneys.
The disorder may be caused by any condition that results in damage to skeletal muscle, especially trauma.
Risk factors include the following:
Additional symptoms that may be associated with this disease include the following:
An examination reveals tender or damaged skeletal muscles.
This disease may also alter the results of the following tests:
Early and aggressive fluids (hydration) may prevent kidney damage by rapidly flushing myoglobin out of the kidneys. Fluids may need to be given through a vein (by IV). Some patients may need kidney dialysis.
Medicines that may be prescribed include diuretics and bicarbonate (if urine output is sufficient).
The outcome varies depending on the extent of kidney damage. Acute kidney failure occurs in many patients. Treatment soon after rhabdomyolysis begins will reduce the risk of chronic kidney damage.
People with milder cases may return to normal activity within a few weeks to a month or more. However, some continue to have problems with fatigue and muscle pain.
Call your health care provider if symptoms indicate rhabdomyolysis may be present.
Drink plenty of fluids after strenous exercise to dilute the urine and flush the myoglobin out of the kidney. Proper hydration is also necessary after any condition or event that may involve damage to skeletal muscle.
In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 114.