Labyrinthitis

Some sources consider vestibular neuritis and labyrinthitis to be the same condition; differentiation is based on the presence of auditory symptoms.

Background

• Inflammation of the inner ear (cochlear and vestibular apparatus)
• Key distinction from vestibular neuritis: Labyrinthitis includes hearing loss in addition to vertigo
• Types:
  • Viral/serous: Most common; follows viral URI; self-limited (similar course to vestibular neuritis)
  • Suppurative (bacterial): Extension from otitis media, meningitis, or mastoiditis — requires urgent treatment

Clinical Features

• Acute, continuous peripheral vertigo (not positional)
• Unilateral sensorineural hearing loss and/or tinnitus (distinguishes from vestibular neuritis)
• Nausea/vomiting
• Unidirectional horizontal nystagmus (fast phase away from affected ear)
• Normal neurologic exam otherwise
• Suppurative form: Fever, otorrhea, signs of systemic toxicity, concurrent otitis media or mastoiditis

Differential Diagnosis

Vertigo

• Vestibular/otologic
  • Benign paroxysmal positional vertigo (BPPV)
  • Traumatic (following head injury)
  • Infection
    • Labyrinthitis
    • Vestibular neuritis
    • Ramsay Hunt syndrome
  • Ménière's disease
  • Ear foreign body
  • Otic barotrauma
  • Otosclerosis
• Neurologic
  • Cerebellar stroke
  • Vertebrobasilar insufficiency
  • Lateral Wallenberg syndrome
  • Anterior inferior cerebellar artery syndrome
  • Neoplastic: cerebellopontine angle tumors
  • Basal ganglion diseases
  • Vertebral Artery Dissection
  • Multiple sclerosis
  • Infections: neurosyphilis, tuberculosis
  • Epilepsy
  • Migraine (basilar)
• Other
  • Hematologic: anemia, polycythemia, hyperviscosity syndrome
  • Toxic
    • Alcohol
    • Aminoglycosides
  • Chronic renal failure
  • Metabolic
    • Thyroid Disease
    • Hypoglycemia

Evaluation

• HINTS Exam: Differentiates peripheral from central cause of acute vestibular syndrome
  • HI: Head impulse test (positive/corrective saccade = peripheral)
  • N: Nystagmus (unidirectional = peripheral; direction-changing = central)
  • TS: Test of skew (vertical skew deviation = central)
• Hearing assessment (bedside finger rub; formal audiometry outpatient)
• Assess for otitis media/mastoiditis on otoscopy
• CT/MRI brain: If HINTS concerning for central cause, or if suppurative form suspected

Management

• Viral/serous:
  • Vestibular suppressants (short-term, 24-72 hours only): meclizine 25 mg PO q6h, diazepam 2-5 mg PO q8h, or promethazine
  • Antiemetics: ondansetron, prochlorperazine
  • Early vestibular rehabilitation (encourage mobilization after acute phase)
  • Corticosteroids controversial but may hasten recovery
• Suppurative: IV antibiotics targeting middle ear pathogens; urgent ENT consult

Disposition

• Viral: discharge with vestibular suppressants (limit to 3 days), antiemetics, PCP/ENT follow-up
• Suppurative: admit for IV antibiotics and ENT evaluation
• Return if: New neurologic symptoms, severe headache, inability to tolerate PO

See Also

• Vertigo
• Vestibular Neuritis (Neuronitis)
• HINTS Exam
• Benign paroxysmal positional vertigo
• Dizziness