Inherited genetic metabolic disorders, including carnitine palmitoyltransferase II (CPT-II) deficiency, should well be presumed in adults with recurrent events of rhabdomyolysis because of its swift evolution and potential severity, a recent study published in the Archive of Clinical Cases showed.
The study emphasized the importance of early and accurate diagnosis for such disorders and highlighted that while the common sources of rhabdomyolysis need to be addressed in the initial treatment approach, the other rare causes requiring a specific treatment should not be excised.
The authors presented a case study of a 22-year-old male patient with a history of recurrent rhabdomyolysis episodes, one of which presented with acute renal failure and acute hepatitis. The diagnostic process was challenging but carefully undertaken, considering all iterations. The patient was ultimately diagnosed with CPT-II deficiency, a long chain fatty acid oxidation disorder (LCFAOD).
Treatment with a carnitine supplement was initiated, followed by dietary restriction of long chain fatty acids, supplementation with medium chain fatty acids, and avoidance of triggers, such as fasting and strenuous exercise. After satisfactory compliance with the treatment, the patient experienced no acute episodes during the following 2 years.
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According to the researchers, infection was found to be the primary cause of the acute presentation of rhabdomyolysis, which rapidly evolved into acute kidney injury and was diagnosed by genetic testing.
The authors wrote that prompt and accurate diagnosis of these disorders is key for effective treatment, improving muscle function, and preventing episodes of rhabdomyolysis.
CPT-II deficiency is a frequently occurring defect in long chain fatty acid oxidation and is a common inherited cause of rhabdomyolysis and myoglobinuria. The patient experiences myalgia and myoglobinuria with brown-colored urine during attacks but is asymptomatic between episodes.
Rhabdomyolysis occurs from the injury of muscle fibers. Its clinical manifestations include myalgia, muscle swelling, and muscle weakness. In some cases, fever, renal failure, liver failure, arrhythmias, and even death might also occur.
Muscle biopsy and genetic testing are frequently used to diagnose metabolic myopathy. Recent research has suggested that muscle biopsy should be performed only after complete recovery from rhabdomyolysis, as taking a biopsy during acute injury may fail to identify the underlying myopathy.
Marques C, Silva C, Silva C, et al. From recurrent rhabdomyolysis in a young adult to carnitine palmitoyltransferase II deficiency. Arch Clin Cases. Published online March 27, 2023. doi: 10.22551/2023.38.1001.10238