Health Encyclopedia

Rhabdomyolysis

Definition

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.

Causes, incidence, and risk factors

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:

Alcoholism (with subsequent muscle tremors)
Certain inherited or genetic syndromes
Crush Injuries
Heat intolerance
Heatstroke
Ischemia or necrosis of the muscles (as may occur with arterial occlusion, deep venous thrombosis, or other conditions)
Low phosphate levels
Seizures
Severe exertion such as marathon running or calisthenics
Shaking chills
Trauma
Use or overdose of drugs, especially cocaine, amphetamines, statins, heroin, or PCP

Symptoms

Abnormal urine color (dark, red, or cola colored)
General weakness
Muscle stiffness or aching (myalgia)
Muscle tenderness
Weakness of the affected muscles

Additional symptoms that may be associated with this disease include the following:

Signs and tests

An examination reveals tender or damaged skeletal muscles.

CPK is very high.
Serum myoglobin test is positive.
Serum potassium may be very high
Urinalysis may reveal casts and be positive for hemoglobin without evidence of red blood cells on microscopic examination.
Urine myoglobin test is positive.

This disease may also alter the results of the following tests:

Treatment

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).

Hyperkalemia and low blood calcium levels (hypocalcemia) should be treated if present. Kidney failure should be treated as appropriate.

Expectations (prognosis)

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.

Complications

Calling your health care provider

Call your health care provider if symptoms indicate rhabdomyolysis may be present.

Prevention

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.

References

In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 114.

Review Date:8/13/2009
Reviewed By:Parul Patel, MD, Private Practice specializing in Nephrology and Kidney and Pancreas Transplantation, Affiliated with California Pacific Medical Center, Department of Transplantation, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

The Agency for Health Care Administration (Agency) and this website do not claim the information on, or referred to by, this site is error free. This site may include links to websites of other government agencies or private groups. Our Agency and this website do not control such sites and are not responsible for their content. Reference to or links to any other group, product, service, or information does not mean our Agency or this website approves of that group, product, service, or information.

Additionally, while health information provided through this website may be a valuable resource for the public, it is not designed to offer medical advice. Talk with your doctor about medical care questions you may have.