Clinical analysis in patients with rhabdomyolysis and acute kidney injury caused by intense exercise

Abstract

Objective To investigate the clinical features of patients with rhabdomyolysis and acute kidney injury (AKI) caused by intense exercise. Methods Data on patients with rhabdomyolysis and AKI due to intense military exercise from January 2002 to December 2017 in a single Chinese nephrology center were retrospectively reviewed. Parameters included clinical manifestations, markers of renal function and muscle damage, treatment and prognosis. Results Twenty-two male servicemen with AKI caused by rhabdomyolysis were included. They took part in the military running training before onset. 95.5%(21/22) took part in 5-kilometer race, of which cross-country was 86.4% (19 cases) and bare-handed was 9.1% (2 cases). Most cases occurred in summer, in which 72.7% (16 cases) took part in 5-kilometer cross-country race. The levels of serum creatinine (Scr), blood urea nitrogen (BUN), uric acid (UA) and creatine kinase (CK) significantly increased in patients, with 9.1% (2 cases) reaching AKI stage 1, 31.8% (7 cases) reaching AKI stage 2, and 59.1% (13 cases) reaching AKI stage 3, respectively. Serum CK levels were positively correlated with AKI stage (r=0.453, P<0.05), Scr (r=0.494, P<0.05) and BUN (r=0.545, P<0.01), while negatively correlated with UA (r=- 0.487, P<0.05). Serum LDH levels were positively correlated only with age (r=0.533, P<0.05). Serum UA presented inverse correlations with BUN (r=- 0.513, P<0.05), K+ (r=- 0.642, P<0.01) and CK (r=- 0.487, P<0.05), and positive correlation with age (r=0.431, P<0.05). In particular, duration from onset of disease had a stronger positive association with BUN (r=0.907, P<0.01) and Scr (r=0.690, P<0.01). Of these patients with AKI, 21 cases(95.5%) reached complete recovery of kidney function and 1 case (4.5%) changed to chronic renal failure within 3 months after comprehensive treatments, including 8 cases(36.4%) who received appropriate continuous venovenous hemofiltration. Conclusions Intense exercise in summer is likely to cause rhabdomyolysis and AKI. Early diagnosis and comprehensive treatment including appropriate blood purification are crucial for a successful treatment. Our findings also emphasize the importance of age on muscle injury and the monitoring of electrolysts, markers of muscle damage and renal function for prevention of rhabdomyolysis and its related complications. Key words: Rhabdomyolysis; Acute kidney injury; Intense exercise; Blood purification