Thrombotic thrombocytopenic purpura presenting with reversible posterior leukoencephalopathy syndrome.

A 48-year-old man presented with consciousness disturbance with vasogenic edema in the occipital lobe on brain CT. The diagnosis of reversible posterior leukoencephalopathy syndrome (RPLS) was made. His hypertension was refractory to treatment, and his neurological disabilities and CT abnormalities, along with renal dysfunction, became worse. Hemodialysis and strict management of blood pressure resolved the neurological findings and the lesions on brain CT. However, one week later, consciousness disturbance and brain CT abnormalities recurred. At that time, hemolytic anemia with fragmented erythrocytes, thrombocytopenia, and renal dysfunction became apparent. We therefore diagnosed thrombotic thrombocytopenic purpura (TTP). Plasma exchange and vincristine administration improved not only the clinical findings of TTP, but also consciousness disturbance and brain CT abnormalities. We concluded that latent TTP had caused RPLS in this patient.