Two cases of malignant hypertension with reversible diffuse leukoencephalopathy exhibiting a reversible nocturnal blood pressure "riser" pattern.

We report two cases of malignant hypertension with reversible diffuse leukoencephalopathy demonstrating a nocturnal blood pressure (BP) rising pattern ("riser" pattern). Case 1 was a 54-year-old man diagnosed with malignant hypertension who presented with diffuse leukoencephalopathy and nocturnal BP rise during the acute phase. These abnormal findings diminished after treatment of hypertension. Case 2 was a 50-year-old woman diagnosed with malignant hypertension in association with leukoencephalopathy, heart failure and acute renal failure. She also presented with a "riser" pattern during the acute phase. In contrast to case 1, the leukoencephalopathy and "riser" pattern in case 2 were not improved even after 1 month of treatment. Following intensive antihypertensive treatment, renal failure was improved in case 1, but renal failure was not improved after 1 month in case 2. In conclusion, a possible explanation of this phenomenon is that a causative volume overload due to renal dysfunction produced the temporal leukoencephalopathy-like brain edema and "riser" pattern in these cases.