Thakur J S, Mohindroo N K, Sharma D R, Soni K, Kaushal S S
Department of Otolaryngology-Head and Neck Surgery, Indira Gandhi Medical College, Shimla, 171001, HP, India.
J Laryngol Otol. 2011 Jun;125(6):567-71. doi: 10.1017/S0022215111000107. Epub 2011 Mar 4.
To investigate the hypothesis of cochlear and retrocochlear damage in scrub typhus, using evoked response audiometry.
Prospective, randomised, case-control study.
The study included 25 patients with scrub typhus and 25 controls with other febrile illnesses not known to cause hearing loss. Controls were age- and sex-matched. All subjects underwent pure tone audiometry and evoked response audiometry before commencing treatment.
Six patients presented with hearing loss, although a total of 23 patients had evidence of symmetrical high frequency loss on pure tone audiometry. Evoked response audiometry found significant prolongation of absolute latencies of wave I, III, V, and wave I-III interpeak latency. Two cases with normal hearing had increased interpeak latencies. These findings constitute level 3b evidence.
Findings were suggestive of retrocochlear pathology in two cases with normal hearing. In other patients, high frequency hearing loss may have led to altered evoked response results. Although scrub typhus appears to cause middle ear cochlear and retrocochlear damage, the presence of such damage could not be fully confirmed by evoked response audiometry.
采用诱发反应测听法研究恙虫病患者耳蜗及蜗后损伤的假说。
前瞻性、随机、病例对照研究。
该研究纳入25例恙虫病患者和25例患有其他已知不会导致听力损失的发热性疾病的对照者。对照者在年龄和性别上相匹配。所有受试者在开始治疗前均接受纯音测听和诱发反应测听。
6例患者出现听力损失，尽管共有23例患者在纯音测听中有对称性高频听力损失的证据。诱发反应测听发现I波、III波、V波的绝对潜伏期以及I-III波峰间期显著延长。2例听力正常的患者波峰间期增加。这些发现构成3b级证据。
在2例听力正常的患者中发现提示蜗后病变。在其他患者中，高频听力损失可能导致诱发反应结果改变。尽管恙虫病似乎会导致中耳、耳蜗及蜗后损伤，但诱发反应测听法无法完全证实此类损伤的存在。
