Portal Systemic Encephalopathy without Significant Changes of Chronic Liver Disease

Abstract

Introduction: Determining the etiology of an encephalopathy can be challenging for the neurologists, especially when the preliminary investigations do not indicate any significant biochemical or other systemic abnormality. Portosystemic shunts maybe easily missed and may present as recurrent encephalopathy with elevated serum ammonia or cerebrospinal glutamate levels. These shunts maybe easily identified in the presence of overt chronic liver disease, but maybe easily missed in patients with cryptogenic liver disease or in congenital abnormalities of the intrahepatic vascular system without an associated chronic liver disease. Materials and Methods: The triple-phase computed tomography (CT) or contrast magnetic resonance imaging can demonstrate the extent of portal vein thrombosis, map the extent of the portosystemic collateral, and aid in planning the treatment in patients with difficult anatomy of the portosystemic collaterals. Treatment regimens for patients with portosystemic shunts manifesting as hyperammonemic encephalopathy include restriction of oral protein intake, lactulose administration, oral nonabsorbable antibiotics, closure of the endovascular shunt, or finally, liver transplant. We present a case of a 55-year-old female with seizure disorder presenting with recurrent episodes of encephalopathy with elevated serum ammonia without the overt signs of chronic liver disease with identification of portosystemic shunting on a triple-phase CT of the abdomen. Conclusion: Specialized investigations to identify the presence of portosystemic collaterals should be conducted in patients with cryptogenic encephalopathy with elevated serum ammonia.