Rhabdomyolysis is a term that refers to breakdown of muscle fibers of skeletal muscle. It is usually a result of various serious conditions with many consequences.
Excessive muscle strain
Extreme physical exercise, especially in untrained individuals, may lead to damage of overloaded muscles that can begin to break down.
Acute occlusion of an artery (that feeds muscle tissue) causes local muscle ischemia (lack of oxygen and nutrients). Typically, this occurs in the lower extremities. If the arterial closure is not solved, the affected tissues die and the muscles succumb to rhabdomyolysis.
This syndrome occurs in people who are buried under rubble or other objects. The prolonged compression of the tissues by external force causes muscle damage and rhabdomyolysis. The situation may be further worsened after the person is rescued due to reperfusion tissue damage.
Medications and other substances
Rhabdomyolysis is a severe side-effect of medications known as statins (commonly used medicines against high cholesterol). Neuroleptics (antipsychotics) can cause severe rhabdomyolysis as a part of feared neuroleptic malignant syndrome. Rhabdomyolysis has been also observed after ingestion of large amounts of alcohol and other addictive substances (cocaine, LSD, etc.).
The muscle damage may manifest with muscle pain and muscle weakness. Decaying muscle fibers release a number of substances such as enzyme known as creatine kinase (CK) and myoglobin. The molecules of myoglobin get into the bloodstream and enter the kidneys, where they can cause acute renal failure.
We should think about the rhabdomyolysis in risky patients. Blood tests are very important for proper diagnosis as we may find elevated creatine kinase and myoglobin blood levels. In case of kidney damage we find elevated renal parameters. The diagnosis can be confirmed also by urinalysis. The urine is dark and it contains large amounts of myoglobin.