[A clinicopathological analysis of 12 cases of cerebrovascular leptospirosis]

12 pathologically verified cases of cerebrovascular leptospirosis were analysed of its clinical characteristics and types. Formation and development of cerebral panarteritis and infarctions were also discussed. It occurred in rural areas among children and adolescents after infection by leptospira pomona, especially following latent infection. Multiple occlusive vascular disorder presenting as a late manifestation of pomona infection occurred in 9 cases, intracranial hemorrhage in 2, and intracranial hypertension in 1 case. Cerebral panarteritis involved the main trunks of larger arteries at the base of the brain. Owing to invariable narrowing of intracranial portions of internal carotid arteries, infarcts always appeared in areas supplied by the middle cerebral artery, often accompanied by marginal infarction at watershed areas. It was suggested that cerebrovascular leptospirosis could be ascribed to residual infection of cerebral arteries soaked in CSF during the septicemic stage of pomona infection.