Case · Trainee · Non-stroke central mimic
Vertigo, ataxia, downbeat nystagmus
72-year-old woman, multiple medications, recent dose increase.
Vignette
A 72-year-old woman is brought in confused and ataxic with persistent vertigo and downbeat nystagmus enhanced by lateral and downward gaze. Her gait is wide-based; she points past the target on finger-to-nose. Her medications include lithium, recently increased.
Diagnostic question
What is the most appropriate next step?
Teaching point
Central HINTS findings can arise from non-vascular causes. Drug toxicity (lithium, antiepileptics, alcohol), cerebellar degeneration, and Wernicke encephalopathy can all produce downbeat nystagmus and ataxia. HINTS flags 'central'; it does not name the lesion.
References: 4