Rhabdomyolysis Following Recovery from Severe COVID-19: A Case Report

BACKGROUND Rhabdomyolysis occurs when muscle injury leads to the release of muscle cell constituents into circulation, often leading to significant systemic complications. There are many causes of rhabdomyolysis, and the etiology is often multifactorial or unclear. Current data suggest that acute COVID-19 may cause muscle injury that can lead to rhabdomyolysis, particularly in cases of severe illness requiring prolonged hospitalization; however, data on the long-term effects of COVID-19 on the musculoskeletal system are lacking. CASE REPORT We present a case of a woman with generalized weakness 1 week following discharge from the hospital after a prolonged admission for severe COVID-19. She was found to have acute kidney injury and elevated creatine kinase (CK) of 1775 U/L (normal 36-234 U/L). Her home medications, including her statin, were held, but her CK continued to rise, peaking at 15 085 U/L, and she developed renal failure necessitating renal replacement therapy. A thorough work-up for the underlying etiology of her rhabdomyolysis was pursued, including testing for autoimmune myositis, statin-associated necrotizing autoimmune myositis, and a muscle biopsy, which were all unrevealing. Ultimately, the patient's rhabdomyolysis was determined to likely be secondary to a post-viral myopathy from COVID-19. A toxic myopathy from medication use or a delayed critical illness myopathy from her recent prolonged hospitalization could have also contributed. CONCLUSIONS This case highlights the wide differential diagnosis of rhabdomyolysis in the setting of recent COVID-19 and prolonged hospitalization. It demonstrates the possibility that muscle injury and resultant rhabdomyolysis may be a late complication of COVID-19 that is not yet fully described in the literature.