Acute ischaemic pontine stroke revealing lyme neuroborreliosis in a young adult.

We report the case of a 23-year-old male patient who suddenly developed right hemiparesis, cerebellar ataxia, dysarthria, and bilateral dysmetria. Brain magnetic resonance (MR) examination demonstrated hyperacute ischaemic lesions within the pons. CSF analysis revealed a high protein content, lymphocytic pleocytosis, and oligoclonal IgG bands not present in the serum. Elevated IgM and IgG anti-Borrelia burgdorferi antibodies were shown in both serum and CSF samples, associated with an intrathecal synthesis of these antibodies. Ischaemic CNS lesions have been rarely observed as the first manifestation of Lyme neuroborreliosis. The putative mechanism for parenchymal ischaemia is the local extension of inflammatory changes from meninges to the wall of penetrating arterioles.