Rhabdomyolysis-related acute kidney injury in patients with COVID-19.

Background: Viral and bacterial infections may be complicated by rhabdomyolysis, which has a spectrum of clinical presentations ranging from asymptomatic laboratory abnormalities to life-threatening conditions such as renal failure. Direct viral injury as well as inflammatory responses may cause rhabdomyolysis in the course of coronavirus disease 2019 (COVID-19). When presented with acute kidney injury (AKI), rhabdomyolysis may be related to higher morbidity and mortality.

Aim: To compare rhabdomyolysis-related AKI with other AKIs during COVID-19.

Methods: A total of 115 patients with COVID-19 who had AKI were evaluated retrospectively. Fifteen patients had a definite diagnosis of rhabdomyolysis (i.e., creatine kinase levels increased to > 5 times the upper normal range with a concomitant increase in transaminases and lactate dehydrogenase). These patients were aged 61.0 ± 19.1 years and their baseline creatinine levels were 0.87 ± 0.13 mg/dL. Patients were treated according to national COVID-19 treatment guidelines. They were compared with patients with COVID-19 who had AKI due to other reasons.

Results: For patients with rhabdomyolysis, creatinine reached 2.47 ± 1.17 mg/dL during follow-up in hospital. Of these patients, 13.3% had AKI upon hospital admission, and 86.4% developed AKI during hospital follow-up. Their peak C-reactive protein reached as high as 253.2 ± 80.6 mg/L and was higher than in patients with AKI due to other reasons (P < 0.01). Peak ferritin and procalcitonin levels were also higher for patients with rhabdomyolysis (P = 0.02 and P = 0.002, respectively). The mortality of patients with rhabdomyolysis was calculated as 73.3%, which was higher than in other patients with AKI (18.1%) (P = 0.001).

Conclusion: Rhabdomyolysis was present in 13.0% of the patients who had AKI during COVID-19 infection. Rhabdomyolysis-related AKI is more proinflammatory and has a more mortal clinical course.