Are laboratory workups (lab tests) indicated in cases of vertigo?

Laboratory Workups Are NOT Indicated in Routine Vertigo Evaluation

Laboratory testing should not be routinely ordered in patients presenting with vertigo, as the diagnosis relies on clinical history and physical examination, not blood work. 1

Why Laboratory Tests Are Not Recommended

The American Academy of Otolaryngology-Head and Neck Surgery explicitly recommends against routine testing in vertigo cases because:

• Laboratory tests do not improve diagnostic accuracy for the most common causes of vertigo (BPPV, vestibular neuritis, Meniere's disease) 1
• Testing adds unnecessary costs without changing management in the vast majority of cases 1
• Diagnosis is clinical, based on history, physical examination, and specific maneuvers like the Dix-Hallpike test 1
• Testing delays treatment when the diagnosis can be made immediately at the bedside 1, 2

What Testing IS Actually Needed

For Benign Paroxysmal Positional Vertigo (BPPV)

• Dix-Hallpike maneuver is diagnostic for posterior canal BPPV (most common type) 1
• Supine roll test if horizontal nystagmus or negative Dix-Hallpike with compatible history 1
• No imaging, no vestibular testing, no audiometry, no blood work when diagnostic criteria are met 1

Clinical History Distinguishes Common Causes

• BPPV: Brief episodes (seconds) triggered by specific head positions 3, 4
• Vestibular neuritis: Single prolonged episode (hours to days) of continuous vertigo 3, 4
• Meniere's disease: Episodic vertigo with unilateral hearing loss, tinnitus, aural fullness 3, 4
• Migraine-associated vertigo: Recurrent episodes with headache history 4

When Additional Testing IS Indicated

Red Flags Requiring Further Workup

Specialized testing or imaging becomes appropriate only when:

• Neurological signs present: Diplopia, dysarthria, ataxia, focal weakness suggesting central pathology 1, 5, 3
• Atypical presentation: Symptoms inconsistent with common peripheral causes 1, 2
• Treatment failure: Persistent symptoms after appropriate repositioning maneuvers 1, 2
• Unclear diagnosis: Equivocal or unusual nystagmus patterns on examination 1, 2
• Multiple concurrent disorders suspected: Complex presentations suggesting overlapping pathology 1, 2

Appropriate Testing When Indicated

• MRI brain (not CT): For suspected central causes with neurological symptoms 1, 6, 5
• Audiometry: Only if hearing loss is part of the presentation or diagnosis unclear 1, 7
• Vestibular function testing (ENG/VNG): Reserved for atypical cases, treatment failures, or when diagnosis remains unclear after clinical assessment 1, 2, 6
• CT temporal bone: For suspected superior canal dehiscence, temporal bone fracture, or pre-surgical planning 1

Common Pitfalls to Avoid

• Do not order "routine vertigo workup" labs (CBC, metabolic panel, thyroid function) as these do not aid diagnosis 8
• Do not substitute testing for a thorough history - this is the most common error in vertigo evaluation 8, 3
• Do not order MRI for typical BPPV - costs are not justified and imaging does not improve diagnostic accuracy 1
• Do not assume normal vestibular tests rule out disease - results fluctuate and correlate poorly with symptoms 2, 6
• Recognize that elderly patients may have multifactorial dizziness requiring more careful evaluation, but still not routine labs 7

The Bottom Line

The diagnosis of vertigo is clinical, made through detailed history and targeted physical examination including positional testing. 5, 8, 3 Laboratory blood work plays no role in routine evaluation and should not be ordered unless specific systemic conditions are suspected based on additional symptoms beyond vertigo itself. 8, 3