We read the article by Oksi et al 1 describing three patients withBorrelia burgdorferi infection and intracranial aneurysms with great interest.We encountered a patient with neuroborreliose and an aneurysm of the basilar artery, whom we describe.

A previously healthy 33 year old man presented with headache and progressive right hemiparesis. On neurological examination there was right facial weakness, moderate weakness of the right arm and leg (3/5), and brisk deep tendon reflexes. A right Babinski’s sign was present. Cerebral CT and MRI showed left anterior infarction, without enhancement with contrast. Examination of CSF disclosed 246 leucocytes/mm³; the protein content was 3.49 g/l. The IgG index was raised to 1.35. The CSF was xanthochromic, because of bilirubin. IgG antibodies against Borrelia burgdorferi in CSF were detected. A cerebral angiogram showed narrowing of the left anterior cerebral artery and an aneurysm of the basilar artery. Serum IgG antibodies againstBorrelia burgdorferi were detected. Investigations for other disorders were normal. We concluded that our patient had neuroborreliosis and he was treated with ceftriaxon intrvenously for 14 days. There was an almost complete recovery.

The diagnosis of neuroborreliosis in this patient is supported by the clinical presentation with right hemiparesis, positive …