Down Syndrome Patients with Congenital Portosystemic Shunts: A Case Report and Review.

Introduction: Down syndrome is due to trisomy 21 and is characterized by intellectual disability, dysmorphic facial features, congenital malformations, and gastrointestinal abnormalities. There is an increased appreciation of congenital portosystemic shunts in Down syndrome patients. Congenital portosystemic shunts have been associated with many defects in body systems, including cardiac, metabolic, and neurological. Case Presentation: Herein, we describe a portosystemic shunt in a Down syndrome patient that resulted in hyperammonemia with altered mental status and choreiform movements. Computed tomography angiography of the abdomen and pelvis identified a connection between the right portal vein and inferior vena cava. An 18 mm Amplatzer PFO closure device was placed within the congenital shunt, significantly improving symptoms. The patient has no sequelae from the related shunt or the device at the 2-year follow-up. We extensively reviewed the literature and identified cases of portosystemic shunts in Down syndrome patients. Shunts can either be extrahepatic or intrahepatic and are classified by vasculature connections. Conclusion: From our literature review and case presentation, we identify other conditions in patients, including cardiac and gastrointestinal defects. We then review the available treatment options, whether observation or surgical, depending on the patient's clinical picture.