めまい，難聴を伴った抗MOG（myelin oligodendrocyte glycoprotein）抗体陽性関連疾患の1例

抄録

We report a case of a 44-year-old man who presented with dizziness, left sensorineural hearing loss, leg numbness, and gait disturbance. Initial MRI of the head and spine and CSF examination revealed no abnormal findings. Neurotological examinations suggested a central pathology: Auditory Brainstem Response (ABR) showed a loss of waves II and subsequent waves, and Vestibular Evoked Myogenic Potentials (VEMPs) revealed bilateral latency delays (cVEMP and oVEMP), indicating decreased neural conduction velocity. The patient’s symptoms, including the hearing and lower limb deficits, responded well to steroid therapy, but relapsed upon steroid discontinuation. After a second relapse six months later, a repeat spinal MRI revealed myelitis, and Anti-Myelin Oligodendrocyte Glycoprotein (MOG) antibody was detected in the CSF, which led us to make a definitive diagnosis of Anti-MOG Antibody-Positive Myelitis.

Conclusion: This case highlights that neurotological tests (ABR, VEMP, vHIT) can reveal characteristic signs of demyelinating CNS disorders, such as delayed conduction velocity, even when the initial MRI findings are normal. Such physiological tests are valuable tools for suspecting and diagnosing CNS inflammatory demyelinating diseases, including Anti-MOG antibody-associated disease.