Serum heat shock protein 70 and its correlation with clinical characteristics in patients with sudden sensorineural hearing loss

OBJECTIVES: Previous studies have reported that in cochlear cells, heat shock protein (HSP)70 is expressed after ototoxic stimuli. We performed this study to investigate the possibility of HSP70 being found in circulation and to observe its possible clinical role in patients with sudden sensorineural hearing loss (SSNHL). METHODS: A total of 67 patients with SSNHL and age-sex matched normal controls were included in this study. Their serum HSP70 levels were measured with highly sensitive enzyme-linked immunoadsorbent assay (ELISA) test and confirmed with Western blot immunoassay. Clinical variables including initial and final audiometric findings and accompanying symptoms were analyzed to find the possible clinical value of serum HSP70 level in the patients with SSNHL. RESULTS: Serum HSP70 levels were significantly higher in the patients with SSNHL than those of normal controls by ELISA test (P < .01), and their presence were confirmed as strong bands in the Western blot assay. There was significant correlation between serum HSP70 levels and the recovery of HL in the patients with SSNHL (P < .0l). CONCLUSION: This is the first report showing elevated serum HSP70 levels in the patients with SSNHL compared with normal controls. We suggest that serum HSP70 levels might have a clinical role for predicting prognosis of HL in the patients with SSNHL.