Neurosyphilis presenting as a new onset lateralized movement disorder.

We report a unique and illustrative case of a 52-year-old man with neurosyphilis presenting as subacute hemichorea, and discuss a vascular, metabolic or inflammatory origin. A broad range of neurological findings may be linked to neurosyphilis, potentially complicating its diagnosis. We propose that new onset lateralized movement disorders may constitute the initial clinical presentations of neurosyphilis, and provide evidence for striatal hypermetabolism pointing to direct inflammatory, syphilitic changes as the underlying pathophysiological mechanism. Neurosyphilis is no longer a common disorder, but the prevalence of syphilis is rising again in Western countries and its past reputation as the great imitator should not be forgotten.