What are the likely causes and recommended work‑up and management for a 30‑year‑old woman with a 5‑day history of oscillopsia and dizziness on position changes, normal neurologic exam, negative Romberg, and recent renal colic with residual flank pain, normal urinary stream, and no dysuria or gross hematuria?

Positional Vertigo with Oscillopsia: Likely BPPV with Unrelated Renal Colic

This 30-year-old woman most likely has benign paroxysmal positional vertigo (BPPV) causing her positional dizziness and oscillopsia, with her ongoing flank pain representing residual discomfort from recent nephrolithiasis—two separate, unrelated conditions.

Primary Diagnosis: Benign Paroxysmal Positional Vertigo

Why BPPV is Most Likely

• BPPV is the most common cause of vertigo in young adults, accounting for 42% of peripheral vertigo cases, and characteristically presents with brief episodes triggered by position changes (sitting to standing, lying to sitting). 1
• The 5-day duration fits BPPV, which can persist for days to weeks if untreated. 1
• "Eyes shaking" (oscillopsia) during positional changes is consistent with the transient nystagmus that occurs with BPPV, though patients typically describe room-spinning rather than eye movement. 2, 3
• Her benign neurologic exam and negative Romberg effectively rule out central causes. 1

Immediate Diagnostic Maneuver Required

Perform bilateral Dix-Hallpike maneuvers immediately to confirm or exclude BPPV:

• Move the patient from seated to supine, turning the head 45° to the tested side and extending the neck ≈20°. 1
• A positive result shows torsional upbeating nystagmus with 5–20 second latency, lasting <60 seconds, and fatiguing with repeated testing. 1, 3
• If Dix-Hallpike is negative bilaterally, perform the supine roll test (rapidly turn head 90° to each side while supine) to detect lateral-canal BPPV (10–15% of cases). 1

Treatment if BPPV Confirmed

• Perform the Epley (canalith repositioning) maneuver immediately upon positive Dix-Hallpike, which achieves 80% success after 1–3 treatments and 90–98% with additional attempts. 1
• Do NOT prescribe vestibular suppressants (meclizine, dimenhydrinate) for BPPV, as they prevent central compensation and delay recovery. 1
• No postprocedural postural restrictions are necessary. 1

Alternative Diagnoses to Consider

Vestibular Neuritis

• Presents with acute continuous vertigo lasting days to weeks (not brief positional episodes), accounts for 41% of peripheral vertigo. 1
• Would show unidirectional horizontal nystagmus even without head movement. 3
• Less likely given the clear positional triggers in this case. 1

Vestibular Migraine

• Extremely common in young women (lifetime prevalence 3.2%), accounts for up to 14% of vertigo cases. 1, 4
• Episodes last 5 minutes to 72 hours with migraine features (photophobia, phonophobia, visual aura). 1
• Requires ≥5 episodes with current or past migraine history. 1
• Consider if BPPV maneuvers are negative and patient reports headache, light sensitivity, or motion intolerance. 1

Red Flags Requiring Urgent MRI (All Absent in This Case)

None of the following are present, so neuroimaging is NOT indicated: 1, 5

• Severe postural instability with falling
• New-onset severe headache
• Focal neurologic deficits (dysarthria, dysmetria, dysphagia, weakness, numbness)
• Pure vertical or downbeating nystagmus without torsional component
• Direction-changing nystagmus without head position changes
• Baseline nystagmus without provocative maneuvers
• Failure to respond to appropriate BPPV treatment

The diagnostic yield of CT or MRI for isolated positional dizziness without red flags is <1%. 1, 5

The Kidney Stone Issue: Separate and Unrelated

Why the Flank Pain is Not Causing Vertigo

• Renal colic causes severe unilateral flank pain, often with nausea/vomiting and occasionally hypotension/syncope, but does NOT cause vertigo or oscillopsia. 6, 7
• Her pain is residual from stones diagnosed 3 months ago, with good urine flow and no acute obstruction signs. 6
• Positional orthostatic symptoms from volume depletion would cause lightheadedness, not oscillopsia or "eyes shaking." 8

Management of Residual Renal Colic

• For ongoing flank pain, NSAIDs (diclofenac 50–75 mg IM or oral) are first-line, with morphine reserved for inadequate NSAID response. 7, 9
• Screen for NSAID contraindications (renal impairment, peptic ulcer disease, pregnancy). 7, 9
• Ensure adequate hydration but avoid excessive fluid intake. 6
• Stones <5 mm have high spontaneous passage rates; consider alpha-blocker (tamsulosin) to facilitate passage, which increases spontaneous passage by ≈50%. 7
• Arrange urology follow-up for persistent stones or recurrent symptoms. 6

Common Pitfalls to Avoid

• Do not assume vertigo and kidney stones are related—they represent two distinct pathologies requiring separate evaluation. 1, 6
• Do not order brain imaging for typical positional vertigo with benign exam and no red flags—the yield is <1%. 1, 5
• Do not prescribe vestibular suppressants if BPPV is confirmed—they delay recovery. 1
• Do not assume BPPV without performing Dix-Hallpike and supine roll tests—clinical history alone is insufficient. 1, 5
• Approximately 10% of cerebellar strokes mimic peripheral vertigo, but this patient's benign neuro exam, negative Romberg, and clear positional triggers make stroke extremely unlikely. 1, 4

Follow-Up Plan

• Reassess within 1 month to document symptom resolution or persistence. 1
• If symptoms persist despite appropriate canalith repositioning, repeat Dix-Hallpike to confirm ongoing BPPV or consider alternative diagnoses (vestibular migraine, vestibular neuritis). 1
• Worsening symptoms or new neurologic signs warrant urgent neuroimaging. 1, 5