Asymptomatic Brain Edema after Hemodialysis Initiation in a Patient with Severe Uremia

A 66-year-old man with severe renal insufficiency presented with mild confusion associated with uremia. Cranial magnetic resonance imaging (MRI) showed no remarkable changes. The patient was placed on short-duration hemodialysis (2 hours) with smaller surface area and low blood flow (100 mL/min) to avoid dialysis disequilibrium syndrome (DDS). His consciousness gradually improved and he did not develop apparent DDS symptoms. However, T2-weighted FLAIR MRI showed increased signal intensities bilaterally in the cortical and subcortical areas of the occipital lobe on day 15. In other words, cranial MRI showed cerebral edema, indicating asymptomatic DDS. On day 29, cranial MRI showed a return to findings on admission. In this case, because the patient did not have apparent DDS symptoms despite MRI changes, we diagnosed asymptomatic cerebral edema. The patient was discharged on regular intermittent HD without any neurological deficits. No further neurological disturbances were noted during 1-year follow-up. MRI findings in ESKD patients without DDS symptoms help to clarify the diagnosis of cerebral edema. In this case, the patient did not have apparent DDS symptoms and was therefore diagnosed with asymptomatic cerebral edema.