[Reversible posterior leukoencephalopathy syndrome probably caused by L-asparaginase].

A 46-year-old male with refractory biphenotypic acute leukemia was treated with doxorubicin (days 1-3, 15-17), vincristine (days 1, 8, 15, 22), prednisolone (days 1-28), and L-asparaginase (L-ASP: days 15-28) as reinduction therapy. Physical examination revealed normotensive state and normal consciousness. On the 27th day, systemic seizures developed with mild hypertension (BP 151/98 mmHg). Computed tomography (CT) imaging of the brain showed areas of hypodensity in the bilateral white matter, and in the occipital and posterior parietal areas. Fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) showed some high intensity area involving the white matter, but also involving the cortex in the same area. Because the patient's condition progressed into unconsciousness and apnea from recurrent seizures, a respirator and anticonvulsants were needed. Four days later, the patient's general condition dramatically improved. There were no abnormal findings on MRI, and we diagnosed the cause of the seizures as reversible posterior leukoencephalopathy syndrome (RPLS). In adults, RPLS caused by chemotherapy is rare, especially L-ASP. Our patient did not have any previous history of convulsion up to the LAdVP, which brought on the seizures. It was considered that the RPLS might be caused by L-ASP, which had been given to this patient for the first time and was being given to him at the time of developing the seizures. RPLS is one of the causes of neurologic complications by L-ASP.