INTRODUCTION
Rhabdomyolysis refers to the breakdown of skeletal muscle cells with the release of their intracellular constituents into circulation, such as myoglobin, enzymes (creatine kinase, transaminases, lactate dehydrogenase) and electrolytes (potassium, phosphate) [1-3]. Its causes may be physical such as trauma/ crush injury, prolonged immobilization, intense muscle activity (seizure, exertion, neuroleptic malignant syndrome), burns, and electrocution. It can have non-physical causes such as drugs, toxins, venoms, infections, genetic myopathies, dyselectrolytemia, ischemia and more. These non-physical causes induce muscle damage by direct sarcolemmic injury, ATP-depleting and other metabolic mechanisms [2, 3]. Drugs like statins and colchicine cause direct myotoxicity whereas cocaine and amphetamines cause vasoconstrictive ischemia [4, 5]. Concurrent usage of statins with other drugs like steroids, cyclosporine, gemfibrozil and CYP450 inhibitors in general, increases the risk of statin-induced rhabdomyolysis. Of the many complications of rhabdomyolysis, pigment (myoglobin)-induced acute kidney injury (AKI) is common, seen in up to 30% of cases, especially so when CK levels are more than 5000 IU/L [2].
COVID-19 is a known infectious cause of rhabdomyolysis, however, literature suggests that usually only severe COVID-19 leading to hypoxia causes rhabdomyolysis due to energy supply-demand mismatch [1]. Often, other risk factors are concurrently present with severe COVID-19, that may contribute to this, such as old age, diabetes, hypertension, hypothyroidism, injury, inborn errors of metabolism, and use of myotoxic drugs like statins, fluoroquinolones, macrolide antibiotics, HIV protease inhibitors, antipsychotics, and chemotherapy agents [1, 6]. Notably, the SARS CoV-2 virus spike protein is known to cause host cell mitochondrial dysfunction, leading to altered bioenergetics and cellular breakdown in muscles [1]. Asymptomatic COVID-19-associated rhabdomyolysis and AKI is a less reported occurrence [7]. This article will discuss this rare scenario, focusing on underlying risk factors.