Rhabdomyolysis and Acute Kidney Injury: Exploring the Potential Causes in a Hospitalized Patient

Rhabdomyolysis refers to the breakdown of skeletal muscle with subsequent release of intracellular contents into blood, causing elevated creatine kinase (CK) and renal damage. The four main etiological categories are traumatic, non-traumatic, non-traumatic exertional, and non-traumatic non-exertional. We report a case of a young female who presented with rhabdomyolysis due to agitation, increased motor activity, and venlafaxine use, resulting in severe organ dysfunction. A 30-year-old female on venlafaxine, pregabalin, and fentanyl patch presented to our hospital with a sudden onset of generalized pain and agitation. Before presentation, the patient was flailing her extremities and thrashing herself against the wall, and the patient became more confused, which prompted the mother to bring her to our emergency department. She had icterus, diffuse ecchymosis over bilateral upper and lower extremities, edematous extremities, and generalized weakness of all extremities with 3/5 strength, normal reflexes without rigidity or clonus or tremors. At presentation, the patient had elevated CK, elevated creatinine, transaminitis, international normalized ratio (INR) of 5.4, and ammonia of 126 umol/L. Given rhabdomyolysis and non-oliguric acute kidney injury, the patient was started on aggressive intravenous hydration at admission. However, her creatinine worsened in the next 24 hours, and the patient developed a worsening of creatinine with high anion gap metabolic acidosis. The patient was given a Lasix challenge and sodium bicarbonate infusion to aid in the excretion of myoglobin and N-acetylcysteine infusion for worsening liver function. She became anuric despite diuretics, developed acute tubular necrosis, and was started on intermittent hemodialysis. Over the next few days, her urine output improved and her creatinine gradually improved. During her hospital course, her mental status returned to baseline, she was started on physical therapy as tolerated, her lower extremity strength gradually improved, and she was discharged to an inpatient rehabilitation facility. Agitation is one of the most common presentations to the emergency department and can cause rhabdomyolysis. Careful monitoring, evaluation of other coexisting causes of rhabdomyolysis, and early aggressive hydration are of paramount importance. Additionally, the use of prediction tools such as the McMahon score can aid in identifying patients who will need renal replacement therapy.