Rhabdomyolysis: Information on Causes, Diagnosis & Treatments
Rhabdomyolysis (skeletal muscle rapid breakdown) is a serious condition that involves the breakdown of the body's muscle tissue caused b an indirect or direct injury. This syndrome destroys muscle fibers and releases the dead tissue into the body's bloodstream. Over time, the condition causes serious complications including kidney (renal) failure that leads to the inability to remove waste when urinating.
Rhabdomyolysis can lead to death in rare cases. However, with effective treatment immediately after a diagnosis, many patients have a good prognosis (outlook). Many of the initial warning signs of rhabdomyolysis are subtle. The condition affects only the skeletal muscles out of the three distinct types of muscles in the body that include:
- Cardiac (heart) muscle
- Skeletal muscles attached to the skeleton and provide movement
- Smooth muscles that work in the bronchi in the lung, gastrointestinal (G.I.) tract, and blood vessels.
More than 26,000 individuals are diagnosed with rhabdomyolysis in America every year and receive treatments involving the delivery of fluids through an IV (intravenous) drip. In severe cases, the patient may require hemofiltration or dialysis due to extensive kidney damage.
The condition was first identified in the early 1900s after a volcano erected in Italy leaving it victims with serious glass injuries. Further research was done on rhabdomyolysis during both world wars involving victims who had suffered injuries from explosions.
What Causes Rhabdomyolysis?
Due to the injury to the muscle, the cells begin to leak a protein (myoglobin) into the bloodstream that is often highly toxic to kidney cells. With the buildup of the protein, the damage can significantly clog and impair the kidney filtration system resulting in kidney failure, the most recognized major complication associated with the syndrome.
There are significant risk factors and causes of rhabdomyolysis that involve exposure to toxins, trauma to the body, metabolic and genetic disorders, inflammation, infection and exposure to toxins and drugs. The most common causes of rhabdomyolysis include:
- Third-degree burns
- Bacterial and viral infections
- Snake bites
- prescription Stat medications including Lipitor, Crestor, and Pravachol
- Exposure to toxic drugs including cyclosporine, cocaine, and amphetamines, LSD, ecstasy, colchicine, and erythromycin.
- Excessive alcohol consumption
- Crushing injury
- Lightning strike
- Blood vessels that have been blocked or obstructed
- Automobile accidents
- Muscle exertion
- Ischemic injuries caused by inadequate blood supply to the area
- Genetic problems associated with carbohydrates, fats, lipids, or purines
- Hypothyroidism (low levels of thyroid hormone)
- Electrolyte imbalance
- Diabetic ketoacidosis where ketones build up in the body
- Genetic disorders associated with carnitine deficiency, Duchenne muscular dystrophy, lactate dehydrogenase deficiency, and McArdle's disease
As the muscle becomes injured they leak protein into the bloodstream, a significant shift occurs in the electrolytes and fluids that can damage muscle cells. This damage often leads to dehydration and hyperkalemia (elevated latrine potassium levels). When this occurs, it can cause a disturbance of heart rhythm or produce sudden cardiac death caused by ventricular fibrillation or ventricular tachycardia.
The individual should be concerned and seek out immediate medical attention if dark urine is detected or if unexplained muscle weakness/pain develops when taking certain drugs including cholesterol-controlling fibrates and statins.
The damage to the muscles can produce small blood clots that form in the blood vessels leading to serious complications including disseminated intravascular coagulation. As this develops, all the clotting factors and platelets in the bloodstream are totally consumed by the complication leading to spontaneous uncontrollable bleeding.
Muscles can become damaged by a crushing injury that leaves the cells of the muscle swollen, causing compartment syndrome. While the body is able to heal from the syndrome, it might be challenged when fascia (fibrous tough tissue membranes) bind the muscle and cause significant pressure to restrict blood supplying muscle fibers. When the muscle becomes compromised, the cells inside the muscles can die.
Mild to severe symptoms that are most associated with rhabdomyolysis include:
- Muscle aches
- Weakened muscles
- Mental confusion
- Achy sore feeling
- Low urine output
- Dark urine that is often described as bloody urine that instead contains no red blood cells when examined in the laboratory setting
- Swelling of the feet and hands associated with kidney failure
- Diminished urine production
- Shortness of breath caused by excessive buildup of fluids in the lungs
- Hyperkalemia that leads to heart rhythm disturbances, palpitations, lightheadedness, nausea, and overall weakness
- Infrequent urination
- Unexpected excessive bleeding caused by disseminated intravascular coagulation
It is rare for children who suffer from rhabdomyolysis to develop disseminated intravascular coagulation or renal failure. The primary symptoms associated with young patients include weakness and primary muscle aches.
Damage to the muscle often leads to inflammation that can develop into weakening, swelling and tender muscles. Dark urine is produced by the excessive amounts of myoglobin produced by rhabdomyolysis.
Doctors consider rhabdomyolysis to be a major medical event like another serious illness or significant trauma to the body. The condition is often diagnosed after extensive evaluation of associated symptoms, obtaining a patient/family history in performing a comprehensive physical examination.
As a part of the diagnosis, the doctor will attempt to identify the underlying cause of the body's breakdown of muscle tissue. In many cases, the cause is obvious after the patient suffered serious trauma or injury. Other times, the doctor must perform a variety of tests to accurately diagnose the condition.
During the physical examination, the doctor will focus on the injury to the muscle and determine if other symptoms including heart rhythm disturbances, hyperkalemia, or kidney failure are present. The physician will likely order a variety of tests that include:
- Complete Blood Count (CDC)
- Bloodstream potassium level test
- Clotting Profile
- Electrolyte test
- Creatinine and BUN test to determine kidney function
- Creatine Phosphokinase (CPK)
The CPK test can identify chemicals that are known to be released into the bloodstream when damage to the muscle occurs. Highly elevated levels of creatine phosphokinase can usually confirm the diagnosis of rhabdomyolysis.
In addition, the doctor may find the results of the urinalysis test to be extremely helpful to rule out blood in the urine when a microscopic evaluation fails to identify any red blood cells in the blood sample, ruling out many other medical conditions.
If rhabdomyolysis is detected in its initial stage, the condition can be treated successfully without suffering any extensive damage to the kidneys. Common treatments include:
- Fluid Recovery – The doctor will typically begin an IV (intravenous) drip to ensure the patient receives sufficient amounts of fluid as quickly as possible. The fluid likely contains bicarbonate to ensure that the kidney is flushed out the excessive levels of mild globulin.
- Drugs – The patient will likely receive numerous prescription drugs and diuretics to help improve kidney function, treat hyperkalemia, elevate bloodstream potassium levels and balance calcium levels in patients who suffer from hypocalcemia.
- Dialysis – If the patient suffers acute renal failure or extensive kidney damage, they likely will require dialysis where a special machine filters out waste products that are typically excreted by the kidneys.
The long-term prognosis of the patient who suffers from rhabdomyolysis is usually determined by the extent of kidney damage. If permanently damage, the patient may be required to maintain dialysis treatments for the remainder of his or her life, or undergo kidney transplantation.