kidney and urinary tract disorders
Rhabdomyolysis
Introduction
Rhabdomyolysis occurs when muscle fibers damaged by disease, injury, or toxic substances break down and release their contents into the bloodstream. Severe disease can cause acute kidney injury. Common causes include muscle injury and impaired blood flow in damaged tissue, medications, toxic substances, and infections. Less common causes include electrolyte imbalances, endocrine and genetic disorders, extreme exercise, and extremes in body temperature. Symptoms can include muscle pain, weakness, and reddish-brown (or tea-colored) urine, but few people have all of these symptoms. Serious complications include Acute Kidney Injury (also called acute kidney failure). Diagnosis is with blood and urine tests. Treatments are aimed at the cause and any resulting complications (for example, acute kidney injury is treated with intravenous fluids and sometimes Dialysis ). (See also Overview of Kidney Failure .) Normal skeletal muscle function requires proper exchange of electrolytes (electrically charged minerals such as sodium and potassium) across muscle cells (myocytes). This exchange allows the cells to adequately metabolizeadenosinetriphosphate (ATP), a molecule necessary for transporting energy within cells and powering the body’s functions. In rhabdomyolysis the processes that support the normal functioning of skeletal muscle are disrupted, so that myocytes break down and release some of their contents into the bloodstream, including Creatine kinase (CK), a protein that rises when muscle is damaged Myoglobin, an iron-containing protein that transports and stores oxygen in myocytes Electrolytes When the kidneys are functioning normally, they filter all myoglobin and excess creatine kinase out of the bloodstream through urination. High concentrations of myoglobin in the blood can overwhelm and damage the kidneys (causing Acute Kidney Injury ) and other organs. Any form of muscle damage can result in rhabdomyolysis. The most common causes of that damage include Direct injury of the muscle or impairment of blood flow in muscle tissue, such as occurs in crush injuries, Electrical Injuries , Some medications and toxic substances Infection (for example, Influenza (Flu) virus, Some medications and toxic substances (for example, Lipid-Lowering Drugs ) can cause direct muscle damage. Other medications and toxic substances raise levels of medications that could damage muscle (for example, drug interactions involving Less common causes of rhabdomyolysis include Electrolyte disorders (for example, low blood levels of potassium [ Hypokalemia (Low Level of Potassium in the Blood) ] or phosphate [ Endocrine disorders (for example, Diabetic Ketoacidosis ) Genetic disorders (for example, Duchenne Muscular Dystrophy and Becker Muscular Dystrophy or Extreme exercise Prolonged bed rest Extremes in body temperature (for example, Hypothermia [low body temperature]; and disorders accompanied by hyperthermia [high body temperatures], such as 