Metformin-associated Encephalopathy in Hemodialysis

Metformin-associated encephalopathy in maintenance hemodialysis is very rare in literature, till now only three to four cases are published. We report a patient on maintenance hemodialysis from standalone unit presented to us with abnormal neurological signs and symptoms. His medication chart included metformin, which he was taking for quite a long time. Computed tomography brain showed hypointensity in bilateral basal ganglia. Magnetic resonance imaging (MRI) brain showed hyperintensity in T2/fluid-attenuated inversion recovery sequences suggestive of Lentiform fork sign. We stopped metformin, and he was continued on regular hemodialysis. He showed dramatic improvement in neurological manifestations. Two months later, we repeated MRI brain, which showed resolution of basal ganglia changes. We should suspect the possibility of this when a diabetic end-stage renal disease presents with unknown etiology of encephalopathy.