Hemodialysis-Related Portal-Systemic Encephalopathy Possibly Associated with Right Femoral Vein Thrombosis.

In hemodialysis-related portal systemic encephalopathy (HRPSE), transient negative pressure in the inferior vena cava (IVC) during dialysis increases the blood flow through a portal-systemic shunt, leading to encephalopathy. We report the case of a 74-year-old man with a gastrorenal shunt who developed HRPSE for the first time following venous occlusion due to thrombosis around a right femoral tunneled-cuffed hemodialysis catheter. Before the thrombosis dissolved, ammonia levels increased after dialysis. Conversely, after the thrombosis was dissolved, the ammonia levels decreased after dialysis. We hypothesized that venous stasis in the right lower limb due to thrombosis intensified the negative pressure in the IVC during dialysis, triggering HRPSE.