Exertional rhabdomyolysis: a case series of 30 hospitalized patients.

INTRODUCTION: Exertional rhabdomyolysis is a clinical entity of significant muscle breakdown in the setting of exercise. However, clinical course and discharge criteria, once hospitalized, are poorly described. We describe 30 cases of exertional rhabdomyolysis and their hospital course. METHODS: Thirty hospitalized cases with ICD-9 code of 722.88 (rhabdomyolysis) as the primary diagnosis were reviewed from 2010 to 2012. We excluded those with associated trauma, toxin, and heat illnesses. RESULTS: The average length of stay was 3.6 days (range: 1-8 days). Length of stay correlated significantly with peak creatine kinase (CK) levels. The mean admission CK was 61,391 U/L (range 697-233,180 U/L). The mean discharge CK was 23,865 U/L with a wide range (1,410-94,665 U/L). Six cases (20%) had evidence of acute kidney injury, but most had serum creatinine (Cr) <1.7 mg/dL. One had a peak Cr of 4.8 mg/dL. Higher serum Cr levels correlated significantly with lower CK levels. Twenty-nine out of 30 patients were discharged when CKs downtrended. CONCLUSION: Higher peak CK levels predicted longer length of stay. Higher serum Cr significantly correlated with lower CK levels. There did not appear to be any threshold CK for admission or discharge, however, all but one patient were discharged after CK downtrended.