Definition of rhabdomyolysis

Rhabdomyolysis is a serious medical condition that can be life-threatening if not detected and treated early. It is a complex medical condition which occurs when there is necrosis or damage to the muscle tissue, following which it releases a protein (called myoglobin) and electrolytes into the blood circulation and ultimately, urine, potentially causing complications such as damage to the heart and kidneys. Myoglobin and creatine kinase are the two measurable important components in clinical practice for diagnosing rhabdomyolysis, along with monitoring kidney profiles and cardiac markers.

Recognising signs and symptoms of rhabdomyolysis is essential as it could prompt early treatment and management, thereby reducing the likelihood of  complications of rhabdomyolysis, which can cause death. It has also become vital to create awareness of specific activities which could induce rhabdomyolysis. 

Causes of rhabdomyolysis

• Muscle trauma and injuries are a primary cause of rhabdomyolysis. Severe muscle injuries, such as in cases of crush injuries or severe muscle compression caused by motor vehicle accidents, could lead to rhabdomyolysis.¹
• Exercise-induced rhabdomyolysis: Intense and prolonged physical activity, especially where the person is not accustomed to the exercise, and training without a proper warm-up, could cause muscle breakdown and lead to rhabdomyolysis. This is often seen in athletes or military personnel during intense exercise.^1,12
• Genetic disorders: such as McArdle’s disease or carnitine palmitoyl-transferase deficiency (CPT deficiency is a  metabolic disorder causing symptoms like painful muscle cramps, weakness and muscular fatigue, and results in rhabdomyolysis during physical activities.²
• Drugs and substance abuse: Alcohol and substance abuse, in the case of heroin and amphetamine toxicity, can cause rhabdomyolysis. Certain medications or drugs, such as simvastatin,^4,5 potentially cause rhabdomyolysis when combined with other medicines. Taking antipsychotics like amitriptyline, haloperidol, and fluoxetine is also a risk factor for rhabdomyolysis.^1,3
• Infections: Viral or bacterial infections are common precipitants for rhabdomylosis. Several cases reported that rhabdomyolysis is a potential late complication of COVID-19 infection.^6,7

Symptoms of rhabdomyolysis

Clinically, a person with rhabdomyolysis typically presents with this triad of symptoms: 

• Unexpected, unbearable, severe muscle cramps and pains over the shoulder, calves and lower back.
• Muscle fatigue and weakness with difficulty in moving upper and lower extremities.
• Dark urine (tea or cola-coloured) with reduced urination.

However, some individuals might not have muscle-related symptoms of rhabdomyolysis.⁹ Instead, rhabdomyolysis may be diagnosed while diagnosing other health issues or during hospitalisations.

Diagnosis and signs of rhabdomyolysis

• Patient history plays a vital role in diagnosing rhabdomyolysis. In a traumatic accident, a physician usually anticipates the elevation of specific blood components due to muscle damage. It is also wise to ask the affected individual if a family history of the same symptoms occurred prior to the accident, or if there is a history of taking any medications or drugs.
• Physical examinations in rhabdomyolysis may reveal muscle tenderness with tension and sometimes swelling. General manifestations of rhabdomyolysis may be fever, tachycardia, malaise, nausea, vomiting and abdominal pain.
• In rhabdomyolysis, blood tests for creatinine kinase and lactate dehydrogenase will be elevated, indicating muscle breakdown.
• A urine dipstick is used in clinical settings to detect myoglobin or protein in the urine. Myoglobin is also responsible for dark-coloured urine.
• It is also useful to monitor liver markers such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as they could be elevated in cases of liver involvement secondary to rhabdomyolysis. It is one of the complications of rhabdomyolysis.
• To avoid further complications of rhabdomyolysis, such as acute kidney injury that potentially leads to kidney failure, it is best to monitor kidney markers such as blood tests for serum creatinine and blood urea nitrogen (BUN). Electrolyte levels of potassium, calcium and phosphate are also commonly monitored closely in case of rhabdomyolysis.
• In some instances, like recurrent episodes of rhabdomyolysis with extremely high CK, and persistently high CK levels more than eight weeks after the event, healthcare providers could advise a muscle biopsy to assess the musculoskeletal system for abnormalities¹⁰

Treatment and management of rhabdomyolysis

Individuals with rhabdomyolysis need to be monitored closely in an inpatient setting. Fluid replacement and electrolyte correction should be initiated immediately, regardless of renal function, to prevent severe metabolic acidosis and acute kidney injury. The intravenous fluid administered helps to maintain high urine output, which in turn helps flush out myoglobin and avoid kidney damage. Therefore, adequate hydration is vital in rhabdomyolysis.

In the hospital setting, it is essential to assess regularly the kidney function, liver markers and electrolytes to detect and address any signs of kidney damage or liver damage and electrolyte imbalances. 

Addressing underlying issues that cause rhabdomyolysis, such as those caused by medications and toxicity, is also important for the recovery of the individuals. Those medications should be discontinued, and if rhabdomyolysis occurs due to infections, appropriate antibiotics or antivirals should be initiated, considering the drug-to-drug combinations, interactions and toxicity.

The occurrence of rhabdomyolysis can be painful to individuals. Therefore, adequate pain management and bed rest, as well as immobilisation and limiting movement, should be practised on the road to recovery. 

FAQs

Is rhabdomyolysis treatable?

Yes, with early detection and diagnosis of rhabdomyolysis, it is possible for effective management and treatment to be initiated. Therefore, it is important that the general public understands rhabdomyolysis. Treatment involves intravenous fluid and antibiotics or antiviral administrations, monitoring liver and kidney profiles and electrolytes, and managing complications.

Can rhabdomyolysis be prevented?

Rhabdomyolysis can be prevented by staying hydrated during intense physical exercise. It is also crucial to start any physical activities with a good warm-up and gradually increasing exercise intensity. Awareness of the type of medications, their toxicity and side effects is also a good start in preventing rhabdomyolysis.

Can rhabdomyolysis recur?

Recurrence of rhabdomyolysis is possible, mainly if the underlying conditions causing rhabdomyolysis are not addressed. For individuals with a history of rhabdomyolysis, it is advisable to do a regular medical check-up to monitor rhabdomyolysis markers. 

How many weeks does it take to recover from rhabdomyolysis?

Recovery from rhabdomyolysis can vary among individuals depending on the severity of the condition, how soon the treatment was initiated and individual factors. Sometimes, it can take weeks before someone can fully regain their strength. There is a high possibility of full recovery with early intervention and appropriate treatment. hysiotheraphy and gradual physical exercise may be necessary for fullrecovery. Once a healthcare provider gives an all-clear to be able to start exercising again, then you will be able to do so, as long as you do not push too hard; avoid overworking yourself and always listen to your body's capacities. 

Does rhabdomyolysis cause kidney failure?

Rhabdomyolysis can lead to kidney damage or acute kidney injury (AKI). The myoglobin or proteins released from damaged muscle can clog the kidneys and cause acute kidney injury. AKI can be treated with proper hydration and urine output monitoring. However, late interventions and inadequate treatment or hydration can worsen acute kidney injury conditions and lead to severe damage to kidneys or kidney failure. 

What are the complications of rhabdomyolysis?

• Electrolyte disorders such as hyperkalemia (high potassium), hyperphosphatemia (high phosphate), hypercalcemia or hypocalcemia (high or low calcium)
• Metabolic acidosis
• Compartment syndrome
• Acute renal failure
• Cardiac arrhythmias due to electrolyte imbalance
• Disseminated intravascular coagulation
• Long-term muscle weakness or damage
• Liver damage¹¹

What not to do with rhabdomyolysis?

If you have rhabdomyolysis, it is helpful to avoid using anti-inflammatory medications such as ibuprofen, naproxen and aspirin for pain management, as these medications could worsen kidney functions. It is also advisable not to take alcohol during these periods because alcohol could make you more dehydrated, which is not helpful in the process of recovery and could impair more of your kidney’s function.

Summary

Rhabdomyolysis is a condition that arises from the rapid breakdown of skeletal muscle tissue which can become a life-threatening condition. The most significant marker in diagnosing rhabdomyolysis is the detection of myoglobin and creatine kinase in urine and blood tests. 

Recognising the symptoms of rhabdomyolysis is critical, and it is essential for treatment to commence early to avoid complications, as it may be fatal. Therefore, it is vital to create awareness in those engaged in activities that are prone to induce rhabdomyolysis, so that they may recognise the signs and  seek medical intervention in a timely manner. 

Individuals who are at risk for rhabdomyolysis include athletes, those with genetic disorders, those with a history of drug or substance abuse, as well as individuals who are involved in an accident or unfortunate situation that puts harm, stress and damage on their musculoskeletal systems. Rhabdomyolysis may also occur in those with an ongoing infection, including those infected with COVID-19.⁸

The triad of symptoms of rhabdomyolysis are muscular pain and weakness with dark-coloured urine. Diagnosing rhabdomyolysis involves assessing clinical history, physical examinations and specific blood and urine tests. Elevation of creatine kinase and lactate dehydrogenase on blood tests indicates muscle breakdown, and myoglobin in urine indicates leakage occurring in the kidneys due to impaired kidney function.

Treatment of rhabdomyolysis emphasises fluid replacement or hydration with intravenous fluids and simultaneous correction of electrolytes. It is crucial to monitor kidney, liver, electrolytes, cardiac markers, blood gases and urine output and content in clinical settings. It is also essential to address any underlying cause, by discontinuing medications or treating infections if necessary.