What can cause postural vertigo in a patient with a recent history of sepsis (systemic inflammatory response syndrome) secondary to a ureteric stone, who underwent a cystoscopy with ureteral stent insertion?

Differential Diagnosis for Postural Vertigo

Single most likely diagnosis

• Benign Paroxysmal Positional Vertigo (BPPV): This condition is a common cause of postural vertigo and can be triggered by recent medical procedures, including cystoscopy, or by the stress of a septic episode. The movement or manipulation during these procedures can cause otoconia in the inner ear to become dislodged, leading to BPPV.

Other Likely diagnoses

• Vestibular Neuritis or Labyrinthitis: These conditions can be caused by viral infections or post-viral inflammation and might be precipitated by the stress of sepsis. They could lead to vertigo, especially if the vestibular system is affected.
• Orthostatic Hypotension: This condition can occur after a period of bed rest, such as during recovery from sepsis, or due to dehydration and can cause dizziness upon standing.
• Medication Side Effects: Certain medications used during or after the treatment of sepsis or the procedure (e.g., antibiotics, anesthetics) can cause vertigo as a side effect.

Do Not Miss (ddxs that may not be likely, but would be deadly if missed)

• Cerebellar Stroke or Infarct: Although less common, a cerebellar stroke can cause vertigo and is a medical emergency. The recent history of sepsis might increase the risk of thrombotic events.
• Central Nervous System (CNS) Infection: Given the recent episode of sepsis, there's a small chance of CNS infection (e.g., meningitis, encephalitis) that could present with vertigo among other symptoms.
• Severe Hyponatremia or Other Electrolyte Imbalances: These can occur due to various reasons including the treatment of sepsis and can cause neurological symptoms including vertigo.

Rare diagnoses

• Perilymphatic Fistula: A rare condition that can be caused by barotrauma during medical procedures (less likely with cystoscopy but possible with other aspects of care) and leads to vertigo.
• Superior Semicircular Canal Dehiscence: A rare inner ear disorder that can cause vertigo triggered by sound or pressure changes, which might be noticed post-procedure.