Chronic Portal-Systemic Shunt Encephalopathy in a Hemodialysis Patient Treated with Balloon-Occluded Retrograde Transvenous Obliteration

We report a case of chronic portal-systemic shunt encephalopathy in a 79-year-old female hemodialysis patient with end-stage renal disease. Approximately 1 month before admission, she occasionally had a discrepant conversation. It was considered that hepatic encephalopathy was caused by an increase in the ammonia level in the blood flow of the shunt, which had been diagnosed 7 years previously between the splenic vein and the left renal vein. On admission, disturbed consciousness and an elevated serum ammonia level (221 μg/dl) were observed. No change in the shunt diameter was noted. Consciousness improved with conservative treatment, whereas hyperammonemia remained. Balloon-occluded retrograde transvenous obliteration (B-RTO) was performed on the shunt. As a result, hyperammonemia resolved immediately, and the level of ammonia was maintained at approximately 60 μg/dl. The patient often complained of drug-induced constipation; therefore, an increase in the intra-abdominal pressure in addition to ammonia production in the intestinal tract was suspected as the cause of encephalopathy. More than 23 months have passed since the B-RTO therapy, and no symptoms of encephalopathy have been observed yet.