What is Labyrinthitis?
Labyrinthitis is an inner ear disorder characterized by sudden severe vertigo with profound hearing loss and prolonged vertigo lasting more than 24 hours, caused by inflammation of the membranous labyrinth. 1
Clinical Presentation
Labyrinthitis presents with a distinct constellation of symptoms that differentiate it from other vestibular disorders:
- Sudden onset of severe vertigo (spinning sensation) that is prolonged, typically lasting more than 24 hours 1
- Profound hearing loss occurring concurrently with vertigo 1, 2
- Nausea and vomiting accompanying the vertigo 1
- Tinnitus (ringing, buzzing, or other noises in the ear) 3, 4
- Aural fullness (sensation of ear feeling plugged or full) 4
Pathophysiology
The condition results from inflammation of the membranous labyrinth, which can have multiple etiologies:
- Viral infections (most common) - including adenovirus and SARS-CoV-2 1, 4
- Bacterial infections - including Staphylococcus and Streptococcus species 1
- Autoimmune processes 5
- Temporal bone trauma 5
- Hemorrhage or tumor (less common) 5
This inflammation disrupts the transmission of sensory information from the inner ear to the brain, affecting both hearing and balance functions 5.
Key Distinguishing Features
Labyrinthitis differs critically from other vestibular disorders:
- Unlike vestibular neuritis: Labyrinthitis includes hearing loss, whereas vestibular neuritis affects only the vestibular system without hearing loss, tinnitus, or aural fullness 1
- Unlike Ménière's disease: Labyrinthitis is not episodic or fluctuating; symptoms are continuous and do not come in discrete attacks 1
- Unlike BPPV: Labyrinthitis is not positional and lasts much longer than seconds to minutes 1
- Unlike vestibular migraine: Labyrinthitis does not have migraine features or photophobia 1
Prognosis
The prognosis for labyrinthitis is generally poor for complete recovery:
- Hearing recovery occurs in only 20% of cases 2
- 72.5% of patients experience persistent balance problems at long-term follow-up (median 61 months) 2
- Losses are often permanent and do not fluctuate, distinguishing this from Ménière's disease 1
- All patients demonstrate vestibular weakness at initial presentation 2
Clinical Pitfalls
Important considerations to avoid misdiagnosis:
- Do not confuse with vestibular neuritis—the presence of hearing loss is the critical differentiating feature 1
- The prolonged duration (>24 hours) distinguishes it from BPPV or other brief positional vertigo syndromes 1
- Fever and severe otalgia may suggest bacterial etiology requiring more aggressive treatment 1
- Early comprehensive audiological and vestibular evaluation is essential for diagnosis and optimal outcomes 3