What is the differential diagnosis of vertigo?

Differential Diagnosis of Vertigo

Primary Classification Framework

The differential diagnosis of vertigo should be organized by timing and triggers rather than patient descriptors, as this approach provides superior diagnostic accuracy. 1, 2

The American Academy of Otolaryngology-Head and Neck Surgery categorizes vertigo into four distinct clinical syndromes 2, 3:

1. Triggered Episodic Vestibular Syndrome

Brief episodes (<1 minute) provoked by specific head or body position changes 2, 3:

Peripheral Causes:

• Benign Paroxysmal Positional Vertigo (BPPV) - Most common cause, accounting for 42% of general practice vertigo cases 1, 2, 3
• Postural hypotension 1, 2
• Perilymphatic fistula 1, 2
• Superior canal dehiscence syndrome 1, 2

Central Causes:

• Central paroxysmal positional vertigo 1
• Vertebrobasilar insufficiency 1, 2

2. Spontaneous Episodic Vestibular Syndrome

Episodes lasting minutes to hours without positional triggers 2, 3:

Peripheral Causes:

• Ménière's disease - Characterized by episodic vertigo with fluctuating hearing loss, tinnitus, and aural fullness; accounts for 10% of general practice cases and up to 43% in specialty settings 1, 2, 3
• Vestibular migraine - Episodes lasting 5 minutes to 72 hours with migraine symptoms during at least 50% of episodes; accounts for up to 14% of vertigo cases 2, 4, 3

Central Causes:

• Posterior circulation transient ischemic attack - Episodes typically last <30 minutes without hearing loss and may precede stroke by weeks or months 1, 2
• Medication side effects 1, 2

Other:

• Anxiety or panic disorder 1, 2, 4

3. Acute Vestibular Syndrome

Continuous vertigo lasting days to weeks with nausea, vomiting, and intolerance to head motion 2, 3:

Peripheral Causes:

• Vestibular neuritis - Accounts for 41% of peripheral vertigo cases; presents with acute severe vertigo lasting days without hearing loss 1, 2, 3
• Labyrinthitis - Inflammation causing vertigo with associated hearing loss 1, 2
• Posttraumatic vertigo 1, 2

Central Causes:

• Posterior circulation stroke - 10% of cerebellar strokes can present similarly to peripheral vestibular disorders 2, 3
• Demyelinating diseases 1, 2

4. Chronic Vestibular Syndrome

Dizziness lasting weeks to months 2, 3:

Peripheral Causes:

• Medication side effects - Ototoxic medications, particularly aminoglycosides like gentamicin, can cause irreversible vestibular toxicity 2, 3
• Posttraumatic vertigo 1, 2

Central Causes:

• Posterior fossa mass lesions 1, 2
• Central nervous system lesions 1

Other:

• Anxiety or panic disorder 1, 2
• Cervicogenic vertigo 1, 2
• Various medical conditions (toxic, infectious, metabolic) 1

Critical Distinguishing Features: Central vs. Peripheral

Nystagmus Characteristics

Peripheral vertigo nystagmus: 2, 3

• Horizontal with rotatory (torsional) component
• Unidirectional
• Suppressed by visual fixation
• Fatigable with repeated testing
• Brief latency period (5-20 seconds) before onset

Central vertigo nystagmus: 2, 3

• Pure vertical (upbeating or downbeating) without torsional component
• Direction-changing without head position changes
• Direction-switching with gaze
• Not suppressed by visual fixation
• Persistent without modification on repositioning maneuvers
• Baseline nystagmus present without provocative maneuvers

Red Flags for Central Causes

Immediate neuroimaging warranted when: 2, 3

• Downbeating nystagmus on Dix-Hallpike without torsional component
• Pure vertical nystagmus without torsion
• Additional neurological symptoms: dysarthria, dysmetria, dysphagia, sensory or motor deficits, diplopia, or Horner's syndrome 2
• New-onset severe headache with vertigo (suggests vertebrobasilar stroke or hemorrhage) 2
• Severe postural instability 2
• Failure to respond to appropriate peripheral vertigo treatments after 2-3 attempts 2, 3

Diagnostic Maneuvers

Dix-Hallpike Maneuver Interpretation: 3

BPPV (Peripheral):

• Latency period of 5-20 seconds
• Fatigability on repeat testing
• Torsional component present

Central Causes:

• Immediate onset
• Persistent nystagmus
• Purely vertical without torsional component

HINTS Examination (for Acute Vestibular Syndrome): The HINTS examination (Head Impulse, Nystagmus, Test of Skew) demonstrates 92.9% sensitivity and 83.4% specificity for central causes when performed by trained clinicians 5. HINTS+ (adding hearing assessment) increases sensitivity to 99.0% 5.

Common Diagnostic Pitfalls

• Missing cerebellar stroke: 10% of cerebellar strokes present similarly to peripheral vestibular disorders; always assess for neurological signs 2, 3
• Overlooking medication effects: Aminoglycosides and other ototoxic drugs can cause vestibular toxicity 2, 3
• Misinterpreting nystagmus: Pure vertical nystagmus without torsion is central until proven otherwise 2, 3
• Overlooking subtle neurological signs that may indicate central pathology 2
• Misdiagnosing vertebrobasilar insufficiency: Isolated transient vertigo may precede stroke by weeks or months 2
• Ignoring multiple concurrent vestibular disorders: Consider BPPV with Ménière's disease or vestibular neuritis 2