Accident ischémique transitoire révélant une neuroborréliose de Lyme

Ischemic stroke has many etiologies but in 30% of patients the mechanism remains unknown, leading to a search for rare causes. We report the case of a 64-year-old man with no known vascular risk factor. The patient was a hiker who presented isolated phasic disorders leading to the diagnosis of a transient ischemic attack (TIA). The etiological search remained negative excepting for the frail irregular aspect of the left sylvian artery implicated in the symptoms. The patient then developed vertigo without any MRI signs of a vascular event. Lyme serology, in both blood and CSF samples enabled the diagnosis of neuroborreliosis to which the TIA was secondarily attributed due to the vasculitis of the left sylvian artery. Antibiotic therapy provided cure. Lyme disease is a rare cause of stroke but should always be entertained as a possible diagnosis since there is a curative treatment.