Case Presentation: A 66-year-old female with a history of primary hypothyroidism presented to the emergency department with an episode of vertigo. The patient reported a persistent spinning sensation, nausea, vomiting, and tinnitus of the left ear without hearing loss for over 10 hours. Review of systems revealed abnormal gait and findings consistent with hypothyroidism (cold intolerance, weight gain, decreased appetite, constipation, dry skin). The patient denied taking levothyroxine for 5 months. No history of falls, migraines, or recent illnesses were reported. On admission, blood pressure was 118/68 and heart rate was 63. Labs included TSH of 266 mcIU/mL, undetectable T4, and CK 393 units/L. Physical exam revealed 4/5 power in all extremities, delayed deep tendon reflexes, ataxic gait, positive Romberg, and a bilateral horizontal nystagmus at rest that was not suppressed by visual fixation. The Dix-Hallpike maneuver demonstrated a non-fatiguing left-beating nystagmus with a 1-2 second latency that lasted greater than 1 minute. Direction of the nystagmus did not change despite variations in head position and gaze direction. Brain CT and MRI with and without contrast did not reveal any abnormalities. Treatment with levothyroxine led to clinical improvement over 2 days. Patient was discharged with diagnosis of Vestibular Ménière Disease (VMD).

Discussion: The etiologies of vertigo implicated in autoimmune hypothyroidism are peripheral in nature and include Ménière Disease and benign paroxysmal positional vertigo (BPPV). Though exact mechanisms are unknown, there is a strong association between autoimmunity and Ménière Disease. A vestibular subtype of Ménière Disease has been described in the setting of hypothyroidism. Episodes are typically mild, brief, and lack sensorineural hearing loss. Additional symptoms frequently reported include nausea, vomiting, tinnitus, and fatigue. As demonstrated in this case, hypothyroidism may be associated with a mixed presentation of peripheral and central vertigo. The unidirectional horizontal nystagmus, tinnitus, nausea, and vomiting were consistent with a peripheral lesion. However, the lack of sensorineural hearing loss and aural fullness did not align with classical Ménière Disease while the findings from the Dix-Hallpike maneuver were inconsistent with BPPV. Features congruent with a central lesion included nystagmus not suppressed by visual fixation, wide-based ataxic gait, and persistent spinning sensation at rest irrespective of position. However, CT or MRI would have been able to identify central causes. Therefore, the patient was clinically diagnosed with VMD.

Conclusions: Autoimmune hypothyroidism is strongly associated with vestibular causes of vertigo, including Vestibular Ménière Disease. It should be recognized that hypothyroid patients may uniquely present with mixed features of peripheral and central vertigo severe enough for hospital admission. Early recognition of these features may guide appropriate diagnosis and management.