An Unusual Presentation of Rhabdomyolysis and Acute Kidney Injury after Physical Activity: A Case Report.

Exercise-induced rhabdomyolysis refers to the breakdown of striated muscle, which releases intracellular elements into the bloodstream due to heavy physical activity. In rare instances, this condition may be the first clinical manifestation of sickle cell trait (SCT). We report on a 31-year-old woman with post-infectious fatigue who, after suffering mild COVID-19 symptoms 3 weeks prior, presented with intense muscle pain in the ankles, dyspnea, and choluria hours after strenuous physical exercise during a practical test. She sought emergent care the next day, where serum creatinine was measured at 2.4 mg/dL (baseline 1.0 mg/dL) and creatine phosphokinase at 118,000 U/L. She was previously healthy, without regular use of any medication, and habitually sedentary except in training, with no personal or family history of blood or muscle diseases. She was admitted without hemodialysis and discharged after 2 weeks. At 3 months, she had normalization of creatine phosphokinase and creatinine. As an outpatient, other tests were requested. Hemoglobin (Hb) electrophoresis revealed HbA1 of 57.8%, HbA2 of 3.1%, HbF of 0.3%, and HbS of 38.8%, which were compatible with SCT. Evaluation for SCT should be considered in cases of exercise-induced rhabdomyolysis, especially in young, healthy patients.