Auditory brainstem response and audiologic findings in adrenoleukodystrophy: its variant and carrier

Auditory brain stem response, auditory sensitivity, speech discrimination function, acoustic reflex threshold, and reflex decay were studied in seven children with adrenoleukodystrophy (ALD), nine adults with adrenomyeloneuropathy (AMN), one child with neonatal ALD, and two carriers of ALD. Significant auditory dysfunctions were found in only two patients; a retrocochlear type auditory disorder in one child with ALD, and a profound deafness in a child with neonatal ALD. None of the patients showed significant abnormality in acoustic reflex threshold and reflex decay except for one patient with ALD who showed a slightly elevated reflex threshold. All but two ALD patients showed significantly prolonged wave latencies and interwave intervals. The latency values revealed the highest incidence of abnormality in the I to III interval; this was followed by the III to V interval, then by wave I. Significantly, one child with asymptomatic ALD and both heterozygous female relatives showed abnormal ABRs, demonstrating the high sensitivity of ABR in detection of the existence of pathophysiological condition in subclinical or presymptomatic ALD.