Audiovestibular findings in patients with mitochondrial A1555G mutation
Audiovestibular findings in patients with mitochondrial A1555G mutation
复制标题
DOI：
10.1097/00005537-200402000-00031
复制
发表时间：
2004-02-01
期刊：
影响因子：
2.6
通讯作者：
Kitamura, K
中科院分区：
文献类型：
--
作者：
Noguchi, Y;Yashima, T;Kitamura, K
目的：本研究的目的是探讨一组日本患者中A1555 G突变的患病率，并评估与突变相关的听力损害的病理生理学。研究设计：遗传学研究和回顾性病历审查。研究方法：我们筛选了138例无亲缘关系的日本耳聋患者的线粒体DNA A1555 G突变，其中包括63例散发病例和75例具有不同遗传模式的家族性病例。当可用时，携带突变的患者接受听前庭检查，包括言语测听，畸变产物耳声发射（DPOAE）测试，耳蜗电图（ECochG）和眼震电图。结果：63例散发性病例中1例（1.6%）和75例家族性病例中6例（8.0%）携带A1555 G突变。有突变和家族史的患者包括2例常染色体隐性遗传和4例母系遗传。此外，6例氨基糖苷类药物诱导的感音神经性听力损失（SNHL）患者中有2例（33.3%）与A1555 G突变相关。除了一名携带突变的患者外，所有患者都表现出高频SNHL。DPOAE畸变产物水平降低到噪声水平，提示A1555 G突变引起耳蜗性耳聋。耳蜗微音电图显示耳蜗微音电位检测阈值和相应的测听阈值升高。ECochG数据表明，高频SNHL患者的耳蜗毛细胞受损最严重，朝向基底转。眼震电图结果显示无明显前庭功能障碍。结论.筛查A1555 G突变，即使是在特发性双侧SNHL患者中，也可能有助于预防耳聋的进一步发展和/或加速。
Objective: The aims of this study were to explore the prevalence of the A1555G mutation among a group of Japanese patients and to assess the pathophysiology of the hearing impairment associated with the mutation. Study design: Genetic study and retrospective chart review. Methods: We screened for the mitochondrial DNA A1555G mutation in 138 unrelated Japanese deaf patients, including 63 sporadic cases and 75 familial cases with different patterns of inheritance. When available, patients carrying the mutation received audiovestibular examinations, including speech audiometry, distortion-product otoacoustic emission (DPOAE) testing, electrocochleography (ECochG), and electronystagmography. Results: One of 63 sporadic cases (1.6%) and 6 of 75 familial cases (8.0%) carried the A1555G mutation. Patients with the mutation and a familial history included two with autosomal recessive inheritance and four with maternal inheritance. In addition, two of six patients (33.3%) presenting with aminoglycoside-induced sensorineural hearing loss (SNHL) were associated with the A1555G mutation. All but one of the patients carrying the mutation showed high-frequency SNHL. Distortion-product levels of DPOAE were reduced to the noise levels, suggesting the A1555G mutation caused cochlear deafness. Cochlear microphonics in ECochG showed elevation of the detection thresholds and corresponding audiometric thresholds. The ECochG data implied that patients with high-frequency SNHL had impairment of the cochlear hair cells that was most severe toward the basal turn. The electronystagmographic findings indicated no apparent vestibular dysfunction. Conclusions. Screening for the A1555G mutation, even in patients with idiopathic bilateral SNHL, likely would be useful for preventing further development and/or acceleration of the deafness.