Brain-stem auditory evoked responses (BAERs) in patients with chronic renal failure

Brain-stem auditory evoked responses have been investigated in 28 patients suffering from chronic renal failure (17 on diet, 11 on chronic dialysis) during monaural stimulation with 70 dB HL clicks. These responses were abnormal in 32.15% of cases. In 13 out of 15 years with altered BAERs a normal response morphology was present, with progressively more significant latency delays involving all peaks following wave I, while in the remaining two ears some of the components always found in healthy controls were not identifiable. The most prominent abnormality in patients with symptoms referable to peripheral neuropathy was the presence of a prolonged I-II interpeak latency, while in those without symptomatology the I-V and III-V interpeak times and the peak V latency were the most strikingly altered parameters. The incidence of altered BAERs was higher in the group of patients treated with diet than in the dialysed group. When BAERs were followed-up in the hours preceding and following the first dialysis in two patients not included in the previous group, the I-V interpeak time significantly decreased after 26 h from the end of dialysis.