Labyrinthitis

Overview

Labyrinthitis is an inflammatory disorder of the inner ear, specifically affecting the labyrinth - a delicate structure that contains the organs of hearing and balance. This condition occurs when both branches of the vestibulocochlear nerve (the eighth cranial nerve) become inflamed, leading to a combination of hearing symptoms and vertigo. The labyrinth consists of the cochlea, responsible for hearing, and the vestibular system, which maintains balance and spatial orientation. When inflammation disrupts these structures, patients experience a characteristic set of symptoms that can be quite debilitating.

Unlike vestibular neuritis, which affects only the vestibular portion of the nerve and causes isolated vertigo, labyrinthitis involves both the vestibular and cochlear components, resulting in both balance problems and hearing loss. The condition typically develops suddenly, often following a viral upper respiratory infection, and can cause severe vertigo that lasts for days to weeks. While the acute symptoms usually improve within a few weeks, some patients may experience lingering balance problems or hearing changes that persist for months.

The incidence of labyrinthitis is estimated at 3.5 per 100,000 people annually, though this may be an underestimate as milder cases often go unreported. It can affect people of all ages but is most common in adults between 40 and 70 years old. The condition affects men and women equally. While most cases are viral in origin and resolve with supportive care, bacterial labyrinthitis, though rare, can occur as a complication of meningitis or chronic ear infections and requires urgent treatment to prevent permanent hearing loss and other serious complications.

Symptoms

Labyrinthitis symptoms typically begin suddenly and can be severe, significantly impacting daily activities. The hallmark of labyrinthitis is the combination of vertigo with hearing changes.

Primary Symptoms

Vertigo

Severe spinning sensation, worse with head movement, lasting days to weeks

Hearing loss

Usually unilateral, ranging from mild to severe, may be temporary or permanent

Tinnitus

Ringing, buzzing, or roaring sounds in the affected ear

Nausea and vomiting

Often severe, triggered by vertigo and head movements

Associated Symptoms

Imbalance

Difficulty walking, tendency to fall toward affected side

Nystagmus

Involuntary eye movements, typically horizontal

Ear fullness

Sensation of pressure or blockage in the affected ear

Headache

Often accompanying the vertigo and nausea

Symptom Timeline

  • Acute phase (first 1-3 days):
    • Severe, continuous vertigo
    • Intense nausea and vomiting
    • Sudden hearing loss or distortion
    • Unable to walk without assistance
    • Anxiety and panic feelings
  • Subacute phase (days 3-21):
    • Gradual improvement in vertigo
    • Positional vertigo becomes prominent
    • Hearing may start to improve
    • Fatigue from compensation efforts
  • Recovery phase (weeks to months):
    • Residual imbalance, especially in darkness
    • Motion sensitivity
    • Possible persistent hearing changes
    • Occasional brief vertigo episodes

Distinguishing Features

  • From vestibular neuritis: Presence of hearing loss and tinnitus
  • From Ménière's disease: Single prolonged episode rather than recurrent attacks
  • From BPPV: Continuous rather than positional vertigo initially
  • From acoustic neuroma: Sudden onset rather than gradual progression

Causes

Labyrinthitis results from inflammation of the inner ear structures, most commonly due to viral infections, though bacterial causes and other factors can also be responsible.

Viral Labyrinthitis (Most Common)

  • Upper respiratory viruses:
    • Influenza virus
    • Respiratory syncytial virus (RSV)
    • Adenovirus
    • Parainfluenza viruses
  • Herpes viruses:
    • Herpes simplex virus (HSV-1)
    • Varicella-zoster virus (VZV)
    • Epstein-Barr virus (EBV)
    • Cytomegalovirus (CMV)
  • Other viral causes:
    • Measles virus
    • Mumps virus
    • Rubella virus
    • Poliovirus (rare in vaccinated populations)
    • COVID-19 (emerging evidence)

Bacterial Labyrinthitis

  • Meningogenic labyrinthitis:
    • Complication of bacterial meningitis
    • Streptococcus pneumoniae
    • Neisseria meningitidis
    • Haemophilus influenzae
  • Tympanogenic labyrinthitis:
    • Extension from middle ear infection
    • Chronic otitis media with cholesteatoma
    • Acute otitis media complications
  • Hematogenous spread:
    • Septicemia
    • Syphilis (rare)
    • Tuberculosis (rare)

Autoimmune Causes

  • Autoimmune inner ear disease (AIED):
    • Bilateral progressive hearing loss
    • Responds to steroids
    • May be associated with systemic autoimmune diseases
  • Cogan's syndrome:
    • Interstitial keratitis
    • Audiovestibular symptoms
    • Systemic vasculitis features

Other Causes

  • Vascular: Anterior inferior cerebellar artery (AICA) infarction
  • Traumatic: Head injury, barotrauma, acoustic trauma
  • Toxic: Ototoxic medications (aminoglycosides, loop diuretics)
  • Neoplastic: Leukemic infiltration, carcinomatous meningitis

Risk Factors

Several factors increase the likelihood of developing labyrinthitis:

Infection-Related Risk Factors

  • Recent viral infections:
    • Upper respiratory tract infections
    • Flu or flu-like illnesses
    • Viral gastroenteritis
    • Herpes simplex reactivation
  • Ear infections:
    • Chronic otitis media
    • Cholesteatoma
    • Mastoiditis
    • Previous ear surgeries

Age and Demographics

  • Most common in adults 40-70 years
  • Can occur at any age
  • No gender preference
  • Seasonal variation (higher in winter/spring)

Medical Conditions

  • Immunocompromised states:
    • HIV/AIDS
    • Diabetes mellitus
    • Cancer treatment
    • Organ transplant recipients
    • Chronic steroid use
  • Autoimmune disorders:
    • Systemic lupus erythematosus
    • Rheumatoid arthritis
    • Temporal arteritis
    • Antiphospholipid syndrome
  • Vascular risk factors:
    • Hypertension
    • Diabetes
    • Hyperlipidemia
    • Smoking
    • Previous stroke

Lifestyle and Environmental Factors

  • High stress levels
  • Sleep deprivation
  • Excessive alcohol consumption
  • Exposure to loud noises
  • Recent air travel (barotrauma)

Medication-Related Risks

  • Ototoxic medications (aminoglycosides, loop diuretics)
  • High-dose aspirin
  • Certain chemotherapy drugs
  • Some antimalarials

Diagnosis

Diagnosing labyrinthitis requires careful clinical evaluation to distinguish it from other causes of vertigo and to identify potential complications requiring urgent treatment.

Clinical History

  • Symptom onset and progression:
    • Sudden versus gradual onset
    • Preceding illness or triggers
    • Duration and severity of symptoms
    • Associated hearing changes
  • Associated symptoms:
    • Fever, headache, neck stiffness
    • Ear pain or discharge
    • Neurological symptoms
    • Visual changes
  • Medical history:
    • Previous ear problems
    • Recent infections
    • Medications
    • Head trauma
    • Vascular risk factors

Physical Examination

  • Otoscopic examination:
    • Tympanic membrane appearance
    • Signs of middle ear infection
    • Cholesteatoma
    • Hemotympanum
  • Neurological examination:
    • Cranial nerve assessment
    • Cerebellar testing
    • Romberg test
    • Gait assessment
    • Fukuda stepping test
  • Vestibular examination:
    • Head impulse test (HIT)
    • Nystagmus evaluation
    • Dix-Hallpike maneuver
    • Head shake test

Hearing Assessment

  • Bedside tests:
    • Weber test (lateralization)
    • Rinne test (air vs bone conduction)
    • Whisper test
  • Audiometry:
    • Pure tone audiometry
    • Speech audiometry
    • Tympanometry
    • Acoustic reflex testing

Laboratory Tests

  • When bacterial infection suspected:
    • Complete blood count
    • C-reactive protein
    • Blood cultures
    • Lumbar puncture if meningitis suspected
  • Autoimmune workup if indicated:
    • ESR, CRP
    • ANA, anti-dsDNA
    • ANCA
    • Anticochlear antibodies

Imaging Studies

  • MRI with gadolinium:
    • Enhancement of labyrinth or cochlear nerve
    • Rule out acoustic neuroma
    • Detect stroke or demyelination
    • Identify complications
  • CT scan:
    • Temporal bone assessment
    • Cholesteatoma evaluation
    • Fracture detection
    • Mastoiditis

Vestibular Function Tests

  • Videonystagmography (VNG):
    • Caloric testing
    • Positional testing
    • Oculomotor evaluation
  • Video head impulse test (vHIT):
    • Quantifies vestibulo-ocular reflex
    • Identifies affected semicircular canals
  • Vestibular evoked myogenic potentials (VEMP):
    • Assesses otolith function
    • Cervical and ocular VEMP

Differential Diagnosis

  • Vestibular neuritis (no hearing loss)
  • Ménière's disease (episodic attacks)
  • Benign paroxysmal positional vertigo (BPPV)
  • Acoustic neuroma
  • Stroke (AICA territory)
  • Vestibular migraine
  • Perilymphatic fistula
  • Superior semicircular canal dehiscence

Treatment Options

Treatment of labyrinthitis focuses on symptom management, treating underlying causes when identified, and promoting vestibular compensation through rehabilitation.

Acute Phase Management

  • Symptomatic relief:
    • Vestibular suppressants (use sparingly):
      • Meclizine 25-50 mg every 4-6 hours
      • Diazepam 2-5 mg every 6-8 hours
      • Promethazine 25 mg every 6-8 hours
      • Limit use to first 48-72 hours
    • Antiemetics:
      • Ondansetron 4-8 mg every 8 hours
      • Metoclopramide 10 mg every 6 hours
      • Prochlorperazine 5-10 mg every 6 hours
  • Hydration:
    • IV fluids if severe vomiting
    • Electrolyte monitoring
    • Small frequent sips when tolerated

Specific Treatments

  • Corticosteroids:
    • Prednisone 1 mg/kg/day (max 60-80 mg) x 3-5 days
    • Then taper over 7-10 days
    • May improve hearing outcomes
    • Most effective if started within 72 hours
    • Intratympanic steroids for severe cases
  • Antiviral therapy (controversial):
    • Limited evidence for routine use
    • Consider for HSV or VZV suspected
    • Acyclovir 800 mg 5x daily x 7-10 days
    • Valacyclovir 1000 mg TID x 7 days
  • Antibiotics (bacterial labyrinthitis only):
    • High-dose IV antibiotics
    • Based on CSF culture if meningitis
    • Ceftriaxone + vancomycin empirically
    • Surgical drainage if mastoiditis

Vestibular Rehabilitation

  • Early mobilization:
    • Begin as soon as acute nausea improves
    • Gradual increase in activity
    • Avoid prolonged bed rest
  • Vestibular exercises:
    • Gaze stabilization exercises
    • Balance training
    • Habituation exercises
    • Canalith repositioning if BPPV develops
  • Physical therapy program:
    • Customized to patient deficits
    • Progressive difficulty
    • Home exercise program
    • Fall prevention strategies

Hearing Management

  • Monitoring:
    • Serial audiometry
    • Document recovery pattern
    • Identify permanent loss
  • Hearing aids:
    • For permanent hearing loss
    • Consider after 3-6 months
    • May help with tinnitus
  • Tinnitus management:
    • Sound therapy
    • Cognitive behavioral therapy
    • Tinnitus retraining therapy
    • Masking devices

Long-term Management

  • Follow-up care:
    • Regular vestibular assessment
    • Hearing monitoring
    • Psychological support if needed
  • Lifestyle modifications:
    • Avoid sudden head movements initially
    • Good lighting for balance
    • Remove trip hazards
    • Gradual return to driving
  • Secondary prevention:
    • Treat allergies and sinus problems
    • Manage stress
    • Adequate sleep
    • Avoid ototoxic medications

Prevention

While labyrinthitis cannot always be prevented, certain measures can reduce the risk of developing this condition:

Infection Prevention

  • General hygiene:
    • Regular handwashing
    • Avoid touching face with unwashed hands
    • Cover coughs and sneezes
    • Avoid close contact with sick individuals
  • Vaccinations:
    • Annual influenza vaccine
    • Pneumococcal vaccine
    • MMR vaccine
    • Varicella vaccine
    • COVID-19 vaccination
  • Prompt treatment:
    • Early treatment of ear infections
    • Complete antibiotic courses
    • Address chronic sinusitis
    • Manage allergies effectively

Ear Health Maintenance

  • Protect ears from injury:
    • Avoid inserting objects in ears
    • Gentle ear cleaning only
    • Protect from loud noises
    • Proper ear protection in water
  • Regular check-ups:
    • Annual hearing tests if at risk
    • Monitor chronic ear conditions
    • Early intervention for problems

Lifestyle Factors

  • Immune system support:
    • Balanced nutrition
    • Regular exercise
    • Adequate sleep (7-9 hours)
    • Stress management
    • Limit alcohol consumption
    • Avoid smoking
  • Manage underlying conditions:
    • Control diabetes
    • Treat autoimmune disorders
    • Manage cardiovascular risk factors

Environmental Precautions

  • Avoid rapid pressure changes when possible
  • Use proper ear protection during flights if prone to problems
  • Avoid swimming in contaminated water
  • Maintain good indoor air quality

When to See a Doctor

Prompt medical evaluation is important for proper diagnosis and to rule out serious conditions that can mimic labyrinthitis:

Seek Emergency Care Immediately For:

  • Sudden severe vertigo with any of the following:
    • Severe headache ("worst headache of life")
    • Neck stiffness and fever
    • Confusion or altered consciousness
    • Difficulty speaking or understanding speech
    • Facial drooping or weakness
    • Arm or leg weakness
    • Double vision
    • Difficulty swallowing
  • Sudden complete hearing loss in one or both ears
  • Severe vomiting preventing fluid intake
  • High fever with ear pain or drainage
  • Recent head trauma followed by vertigo

See Your Doctor Promptly (Within 24-48 Hours) For:

  • New onset vertigo lasting more than a few hours
  • Vertigo with hearing changes or tinnitus
  • Persistent nausea and vomiting
  • Inability to walk due to imbalance
  • Ear pain or discharge
  • Vertigo following recent infection

Schedule an Appointment For:

  • Recurring episodes of vertigo
  • Persistent imbalance after acute symptoms resolve
  • Ongoing tinnitus or hearing changes
  • Anxiety about symptoms
  • Need for vestibular rehabilitation referral

Follow-up Care:

  • Return if symptoms worsen despite treatment
  • New neurological symptoms develop
  • Hearing continues to deteriorate
  • Vertigo persists beyond expected timeline
  • Falls or injuries due to imbalance
  • Depression or anxiety affecting recovery

References

  1. Strupp M, Brandt T. Diagnosis and treatment of vertigo and dizziness. Deutsches Ärzteblatt International. 2008;105(10):173-180.
  2. Fishman JM, et al. Corticosteroids for the treatment of idiopathic acute vestibular dysfunction (vestibular neuritis). Cochrane Database of Systematic Reviews. 2011;(5):CD008607.
  3. Jeong SH, et al. Vestibular neuritis. Clinical Neurology and Neurosurgery. 2023;51(2):107-115.
  4. Goudakos JK, et al. Corticosteroids vs corticosteroids plus antiviral agents in the treatment of Bell palsy: a systematic review and meta-analysis. Archives of Otolaryngology–Head & Neck Surgery. 2009;135(6):558-564.
  5. Thompson TL, Amedee R. Vertigo: a review of common peripheral and central vestibular disorders. The Ochsner Journal. 2009;9(1):20-26.
  6. Seemungal BM, et al. Vestibular perception and navigation in the congenitally blind. Journal of Clinical Investigation. 2007;117(10):2916-2924.

Medical Disclaimer: This information is for educational purposes only and should not replace professional medical advice. Always consult with a qualified healthcare provider for diagnosis and treatment of medical conditions.