A progressive multifocal neurological syndrome in a 42-year-old woman.

This is the case of a 42-year-old female who presented with transient dizziness. Her symptoms and signs progressed to include dysarthria, ataxia and cognitive decline over 2 years, such that she was unable to care for herself. She died 4 years after first presentation without a diagnosis. Investigations revealed a normochromic normocytic anaemia. Cerebrospinal fluid was normal. Serial computed tomography brain showed a wedge-shaped frontal infarct but no progressive changes. Examination at autopsy showed discoloration of the gray and white matter of the brain and spinal cord.Microscopy of leptomeningeal and parenchymal vessels showed they were filled with atypical B lymphocytes confined to the intravascular space with multiple infarcts in the brain, cerebellum and spinal cord. A diagnosis of intravascular B cell lymphoma was made and is discussed.