What is the differential diagnosis and initial management approach for a patient presenting with vertigo?

Differential Diagnosis of Vertigo

Initial Classification by Timing and Triggers

The differential diagnosis of vertigo is best approached by first classifying the presentation into one of four distinct vestibular syndromes based on timing and triggers, which immediately narrows the diagnostic possibilities and guides subsequent evaluation. 1, 2

Triggered Episodic Vertigo (Brief, Positional)

• Benign Paroxysmal Positional Vertigo (BPPV): Most common cause, accounting for 42% of vertigo cases in general practice, characterized by brief episodes (<1 minute) triggered by specific head position changes (lying down, rolling over, bending down, tilting head back) 1, 2, 3
• Central Paroxysmal Positional Vertigo: Rare central mimic of BPPV that fails to respond to repositioning maneuvers 1
• Perilymphatic Fistula: Positional vertigo following trauma or barotrauma 1, 3
• Superior Canal Dehiscence Syndrome: Vertigo triggered by loud sounds or Valsalva maneuvers 1

Spontaneous Episodic Vertigo (Minutes to Hours, Not Positional)

• Ménière's Disease: Episodic vertigo lasting 20 minutes to hours with fluctuating hearing loss, tinnitus, and aural fullness; accounts for 10% of cases 1, 2, 3
• Vestibular Migraine: Vertigo attacks lasting hours with migraine history (headache, photophobia, phonophobia, visual aura); accounts for 3.2% of cases 1, 2
• Vertebrobasilar Insufficiency/TIA: Episodes typically <30 minutes without hearing loss, may precede stroke by weeks to months 1

Acute Vestibular Syndrome (Continuous, Days)

• Vestibular Neuritis: Acute severe continuous vertigo lasting days without hearing loss; accounts for 41% of cases 1, 2, 3
• Labyrinthitis: Similar to vestibular neuritis but with associated hearing loss 1, 3
• Posterior Circulation Stroke: Cerebellar or brainstem infarction; 10% of cerebellar strokes present with isolated vertigo, and 75-80% of posterior circulation strokes causing acute vestibular syndrome lack focal neurologic deficits initially 1, 2
• Demyelinating Diseases: Multiple sclerosis can present with acute vertigo 1, 3

Chronic Vestibular Syndrome (Weeks to Months)

• Anxiety or Panic Disorder: Chronic dizziness with hyperventilation, though vestibular dysfunction may coexist 1
• Medication Side Effects: Aminoglycosides, anticonvulsants (carbamazepine, phenytoin), antihypertensives, cardiovascular medications 1, 2
• Posttraumatic Vertigo: Persistent symptoms following head injury, may coexist with BPPV 1
• Posterior Fossa Mass Lesions: Tumors (acoustic neuroma, meningioma) causing progressive symptoms 1, 3

Peripheral vs. Central Differentiation

Peripheral Vertigo Characteristics

• Nystagmus: Horizontal with rotatory (torsional) component, unidirectional, suppressed by visual fixation, fatigable with repeated testing 2, 4
• Associated Symptoms: Often includes hearing loss, tinnitus, or aural fullness 2, 3
• Neurologic Examination: Normal except for vestibular findings 2, 4

Central Vertigo Characteristics (Red Flags)

• Nystagmus: Pure vertical without torsional component, direction-changing without head position changes, not suppressed by visual fixation 2, 4
• Neurologic Signs: Limb weakness/hemiparesis (sensitivity 11.4%, specificity 98.5%), truncal/gait ataxia (sensitivity 69.7%, specificity 83.7%), dysmetria (sensitivity 24.6%, specificity 97.8%) 4
• Severe Postural Instability: Inability to stand or walk suggests central pathology 1
• Associated Neurologic Symptoms: Diplopia, dysarthria, dysphagia, facial numbness, limb weakness 1, 2, 3

Additional Differential Considerations

Other Otologic Disorders

• Postural Hypotension: Vertigo provoked by moving from supine to upright position, distinct from BPPV's positional triggers 1
• Cervicogenic Vertigo: Triggered by head rotation relative to body while upright (not relative to gravity), associated with degenerative cervical spine disease 1

Concurrent Diagnoses

• Multiple Vestibular Disorders: BPPV can occur in conjunction with Ménière's disease or vestibular neuritis; clinicians must remain alert for mixed presentations 1
• Posttraumatic BPPV: Traumatic brain injury is a specific cause of BPPV that may coexist with other posttraumatic vestibular symptoms 1

Critical Diagnostic Maneuvers

Dix-Hallpike Maneuver for BPPV

• Technique: Bring patient from upright to supine with head turned 45 degrees to one side and neck extended 20 degrees 2
• Positive Test: Vertigo and nystagmus with 5-20 second latency period, fatigable with repetition 2
• Diagnostic Accuracy: Most peripheral and central causes can be distinguished based on Dix-Hallpike and supine roll test responses 1

HINTS Examination for Acute Vestibular Syndrome

• Components: Head Impulse test, Nystagmus type, Test of Skew 4
• Diagnostic Performance: Sensitivity 92.9%, specificity 83.4% for central causes when performed by trained clinicians 4
• HINTS+: Adding hearing assessment increases sensitivity to 99.0% and specificity to 84.8% 4
• Individual Components: Abnormal head impulse test (sensitivity 76.8%, specificity 89.1%), central nystagmus patterns (sensitivity 50.7%, specificity 98.5%), skew deviation (sensitivity 23.7%, specificity 97.6%) 4

When to Suspect Misdiagnosis

Treatment Failure Indicators

• Persistent BPPV: Failure to respond to 2-3 particle repositioning maneuvers warrants thorough neurological examination and consideration of MRI to exclude CNS pathology 1, 2
• Atypical Features: Absence of typical positional triggers, presence of neurologic symptoms, or unusual nystagmus patterns should prompt reevaluation 1
• CNS Disorders Masquerading as BPPV: Found in 3% of treatment failures; acute brain lesions detected in 6% on CT and 11% on MRI in patients with central paroxysmal positional vertigo 1