What are the differential diagnoses for a patient presenting with dizziness?

Differential Diagnoses for Dizziness

Primary Diagnostic Framework

Categorize dizziness based on timing and triggers rather than the patient's subjective description, as this approach is more diagnostically accurate and guides targeted evaluation. 1, 2

The differential diagnosis should be organized into four vestibular syndromes:

1. Triggered Episodic Vestibular Syndrome (seconds to minutes, positional triggers)

Benign Paroxysmal Positional Vertigo (BPPV) - Most common cause

• Episodes last <1 minute, triggered by head position changes 1, 3
• Diagnosed with Dix-Hallpike maneuver showing 5-20 second latency, torsional upbeating nystagmus toward affected ear, symptoms resolving within 60 seconds 1, 2

Posterior Fossa Structural Lesions - Rare but serious

• Atypical nystagmus patterns or failure to respond to canalith repositioning 2, 3

Superior Canal Dehiscence/Perilymph Fistula

• Triggered by pressure changes (Valsalva, loud sounds) 2

2. Acute Vestibular Syndrome (days to weeks, constant symptoms)

Vestibular Neuritis - Peripheral cause

• Acute persistent vertigo with normal HINTS examination (normal head impulse test, unidirectional horizontal nystagmus, no skew deviation) 1, 2

Posterior Circulation Stroke - CRITICAL to identify

• Approximately 4% of isolated dizziness cases are due to stroke 1, 2
• 75-80% have NO focal neurologic deficits, making clinical exam unreliable 2
• HINTS examination by trained practitioners has 100% sensitivity (vs 46% for early MRI) 1, 2
• Abnormal HINTS findings: normal head impulse test, direction-changing nystagmus, or skew deviation 1

Labyrinthitis

• Similar to vestibular neuritis but with associated hearing loss 4

3. Spontaneous Episodic Vestibular Syndrome (minutes to hours, no specific trigger)

Vestibular Migraine

• Headache, photophobia, phonophobia accompanying vertigo 2
• History of migraines 2, 5

Ménière's Disease

• Associated hearing loss, tinnitus, or aural fullness 1, 2
• Episodes typically last 20 minutes to several hours 4

Transient Ischemic Attack (TIA)

• High vascular risk factors: hypertension, atrial fibrillation 1
• Non-whirling type of dizziness increases stroke risk 1

4. Chronic Vestibular Syndrome (persistent symptoms)

Medication-Induced Dizziness - Leading cause

• Antihypertensives, sedatives, anticonvulsants, psychotropic drugs 2
• Medication review is essential and often reveals reversible cause 2

Psychiatric Disorders

• Depression, anxiety, panic disorder 2
• Presents as vague lightheadedness without true vertigo 4, 6

Bilateral Vestibulopathy

• Progressive symptoms, often from ototoxic medications or bilateral vestibular loss 2

Persistent Postural-Perceptual Dizziness (PPPD)

• Chronic non-vertiginous dizziness exacerbated by upright posture and visual motion 5

Posttraumatic Vertigo

• History of head trauma 2

Cerebellar Ataxia/Posterior Fossa Pathology

• Progressive neurologic symptoms, gait instability 2

Additional Differential Categories

Presyncope/Cardiovascular Causes

Orthostatic Hypotension

• Check orthostatic vital signs 4, 6

Cardiac Arrhythmias

• Atrial fibrillation, bradycardia 1

Disequilibrium (Imbalance without vertigo)

Parkinson's Disease 4

Diabetic Neuropathy/Peripheral Neuropathy 4

Multisensory Deficits - Common in elderly 5

Critical Red Flags Requiring Urgent Evaluation

These findings mandate immediate imaging (MRI preferred) and neurologic consultation:

• Focal neurological deficits 1, 2
• Sudden hearing loss 2
• Inability to stand or walk 2
• Downbeating or central nystagmus patterns 2
• New severe headache 2
• Failure to respond to appropriate vestibular treatments 2
• High vascular risk with acute vestibular syndrome 1

Common Diagnostic Pitfalls to Avoid

• Do not rely on patient descriptions of "spinning" vs "lightheadedness" - these subjective terms are unreliable and do not distinguish benign from dangerous causes 2, 7
• Normal neurologic exam does NOT exclude posterior circulation stroke - 75-80% of posterior circulation infarcts present without focal deficits 2
• Avoid routine imaging for clear peripheral causes - imaging has low yield (<1% for CT, 4% for MRI) in isolated dizziness without red flags 1, 2
• CT is inadequate for stroke evaluation - sensitivity only 20-40% for posterior circulation infarcts; use MRI with diffusion-weighted imaging 2
• HINTS examination requires trained practitioners - results are unreliable when performed by non-experts 2