Ischemic stroke and transient ischemic attack associated with neuroborreliosis: a Danish retrospective cohort

Central nervous system (CNS) vasculitis and stroke are rare manifestations of neuroborreliosis (NB). We aimed to describe the clinical course, paraclinical findings, treatments, and outcomes of patients with ischemic stroke and transient ischemic attack (TIA) associated with NB from a comprehensive patient cohort and compare these findings to existing literature. We retrospectively analyzed data from 3841 patients who underwent intrathecal Borrelia burgdorferi sensu lato antibody index testing at Herlev and Gentofte Hospital between 2016 and 2024. Patients who fulfilled the EFNS criteria for definite or possible NB and had clinical and/or radiological evidence of stroke or transient ischemic attack were included. In total, 413 patients fulfilled criteria for NB. Twelve adults and one child fulfilled our criteria for NB-associated stroke or TIA. Seven out of 13 patients presented with gait difficulty and 4/13 with upper motor neuron signs. Mean cerebrospinal fluid (CSF) glucose and CSF/blood glucose ratio were significantly lower compared to NB patients without cerebrovascular events in our cohort. Seven of 13 presented with cognitive symptoms prior to stroke. Twelve out of 13 had magnetic resonance imaging-verified brain infarctions. One patient died; autopsy confirmed lymphocytic vasculitis. High resolution vessel wall imaging, when performed (n = 3), showed concentric vessel wall enhancement. Cerebrovascular manifestations of NB may present acutely with infarction or with chronic prodromal symptoms preceding stroke or transient ischemic attack. High resolution vessel wall imaging appears to be a promising noninvasive tool, potentially enabling earlier diagnosis and facilitating targeted treatment research.