What is the initial workup for a 15-year-old patient presenting with dizziness?

Initial Workup for a 15-Year-Old with Dizziness

The initial workup should focus on categorizing the dizziness by timing and triggers through targeted history and physical examination, with imaging reserved only for red flag features suggesting central pathology. 1, 2

History: Focus on Timing and Triggers

Do not rely on the adolescent's description of "spinning" versus "lightheadedness"—instead, determine the specific temporal pattern: 1, 3

• Brief episodic (seconds to <1 minute): Triggered by head position changes suggests benign paroxysmal positional vertigo (BPPV) 1, 2
• Acute persistent (days to weeks): Constant symptoms suggest acute vestibular syndrome, requiring differentiation between peripheral versus central causes 1, 3
• Recurrent episodic (minutes to hours): Associated with headache, photophobia, or phonophobia suggests vestibular migraine 1
• Chronic (weeks to months): Consider medication effects, psychiatric causes (anxiety, panic disorder), or posttraumatic vertigo 1

Key associated symptoms to elicit: 1, 2

• Hearing loss, tinnitus, or aural fullness (suggests Ménière disease) 1, 4
• Headache, diplopia, dysarthria, numbness, or weakness (suggests central pathology) 2
• Triggers: positional changes, pressure changes, specific head movements 1

Physical Examination: Targeted Bedside Testing

Perform these specific maneuvers based on the temporal pattern: 1, 3

• Dix-Hallpike maneuver for suspected BPPV: Look for latency period of 5-20 seconds, torsional upbeating nystagmus toward the affected ear, and symptoms that resolve within 60 seconds 5, 1, 2
• Complete neurologic examination including cranial nerves, cerebellar testing (finger-to-nose, heel-to-shin, rapid alternating movements), and gait assessment 3, 2
• Observe for spontaneous nystagmus: Central patterns (downbeating, direction-changing without gaze, purely vertical) are red flags 1, 2
• Orthostatic vital signs to assess for presyncope 4, 6

Laboratory Testing: Minimal Utility

Routine laboratory testing has extremely low yield in adolescents with isolated dizziness and normal examination. 5, 4, 7

• Bedside glucose testing if altered mental status or history suggests hypoglycemia 5
• Pregnancy test in post-menarchal females (affects testing decisions and disposition) 5
• No routine electrolytes, CBC, or metabolic panels unless specific clinical suspicion from history/exam 5, 7

Imaging: Only for Red Flags

Imaging is NOT routinely indicated for typical BPPV or peripheral vertigo patterns. 1, 2

Order MRI brain (without contrast, with diffusion-weighted imaging) ONLY if: 1, 3, 2

• Focal neurological deficits on examination 1, 3
• Sudden unilateral hearing loss 1, 3
• Inability to stand or walk 1, 3
• Downbeating or other central nystagmus patterns 1, 3
• New severe headache accompanying dizziness 1
• Progressive neurologic symptoms 1

Critical pitfall: CT head has only 20-40% sensitivity for posterior circulation stroke and should NOT be used instead of MRI when central pathology is suspected. 1, 2

Treatment Based on Diagnosis

For BPPV (most common cause): Perform canalith repositioning procedure (Epley maneuver) immediately—success rate 90-98%, no medications needed. 1, 3 Counsel about 10-18% recurrence rate at 1 year. 3

For vestibular migraine: Initiate migraine prophylaxis and lifestyle modifications. 1, 3

For suspected vestibular neuritis: Consider vestibular suppressants (short-term only) and vestibular rehabilitation. 4

Critical Pitfalls to Avoid

• Do not assume a normal neurologic exam excludes stroke: 75-80% of posterior circulation strokes have NO focal deficits. 1, 3
• Do not order imaging for straightforward BPPV with positive Dix-Hallpike and no concerning features—this delays treatment unnecessarily. 1, 2
• Do not skip the Dix-Hallpike maneuver—it is the gold standard diagnostic test and guides immediate treatment. 5, 1
• Do not rely on symptom quality alone—timing and triggers are far more diagnostically valuable. 1, 3, 2