Abernethy syndrome is a rare congenital anomaly characterized by an intrahepatic or extrahepatic portosystemic shunt. Most patients are asymptomatic; however, due to the alteration in, or lack of, a portovenous flow, patients with Abernethy syndrome are at high risk of developing sequelae of liver failure. Once these complications develop, the only definitive treatment is transplantation. Patients with Abernethy syndrome are also at a higher risk of developing benign and malignant liver lesions, including hepatic adenomas. Here, we describe the first case of deceased donor liver transplantation as a treatment for a patient with type 1 Abernethy syndrome complicated by large, unresectable hepatic adenoma, found to have focal hepatocellular carcinoma on pathologic examination. Our male patient was found to have elevated liver enzymes at age 33, during a routine outpatient medical appointment. Despite being asymptomatic, his history of prior liver resection prompted CT imaging, which revealed two large liver lesions concerning for hepatic adenomas. When surveillance imaging showed a significant growth of the liver lesions, biopsy was pursued, which confirmed a diagnosis of hepatic adenomas. However, given the size of these lesions, resection was not a viable option for the patient. Instead, the patient underwent liver transplantation at age 41, which he tolerated well. Our case demonstrates the utility of deceased donor liver transplantation as a treatment for patients with Abernethy syndrome complicated by unresectable adenomas.

Congenital extrahepatic portocaval shunt (CEPS) is a rare condition in which a rare congenital vascular anomaly of the portal system is present. CEPS may manifest as pulmonary arterial hypertension (PAH). When diagnosed and treated early, PAH can be reversible. We report a case of a previously asymptomatic woman, who manifested with severe pulmonary hypertension during pregnancy and was consequently diagnosed with CEPS. After unsuccessful medical treatment, urgent lung transplantation was done.

BACKGROUND: Abernethy malformation is a rare condition defined by a congenital extrahepatic portosystemic shunt, often leading to absence or hypoplasia of the intrahepatic portal venous system. Although there are no consensus treatment guidelines, interventional techniques now offer minimally invasive treatment options for Abernethy malformations. This case report describes a case of Abernethy Syndrome Type II where the patient had two separate extrahepatic portosystemic shunts treated with endovascular occlusion with two Amplatzer plugs and demonstrates the feasibility of this treatment for this rare condition. This case was in a young adult, adding to the scarce literature of treatment for Abernethy syndrome in the adult population.
METHODS: We report a case of a 20-year-old female patient with neurocognitive behavioral difficulty, voracious appetite, and chronic encephalopathy secondary to type II Abernethy malformation with not one, but two extrahepatic portosystemic shunts. The patient had failed medical management and was not a liver transplant candidate. Therefore, she presented to us for an endovascular treatment option. The two shunts were treated with endovascular occlusion using Amplatzer vascular plugs. Following embolization, flow into the hypoplastic portal vein improved with near complete occlusion of flow into the portosystemic shunts, thus restoring blood flow into the native portal system. At 3 month follow up, a CT demonstrated complete occlusion of the two portosystemic shunts, and a portal vein diminutive in caliber. The portal vein measured 7 mm in diameter on both pre and post-procedure CT scans. The total volume of the liver was found to be 843 cm3 on pre-procedure CT & 1191 cm3 on post-procedure CT.
CONCLUSIONS: This report demonstrates the feasibility of using endovascular embolization to treat Abernethy II malformations. The management strategy of Type II Abernethy Syndrome should be to redirect blood flow into the hypoplastic native portal system, allowing for physiologic hepatic metabolism of splanchnic blood, hypertrophy of the portal system, and growth of the liver from the increased trophic flow.

Objective: The aim of this single-center retrospective study was to analyze the clinical characteristics, treatment options, and course of neonatal-onset congenital portosystemic shunts (CPSS). Methods: We included all patients with CPSS who presented with clinical symptoms within the neonatal period in our institution between 2015 and 2020. Results: Sixteen patients were identified, including 13 patients with intrahepatic portosystemic shunts (IPSS) and three patients with extrahepatic portosystemic shunts (EPSS). The median age of diagnosis was 16 days (range prenatal 24 weeks-12 months). Hyperammonemia (60%), neonatal cholestasis (44%), elevated liver enzyme (40%), hypoglycemia (40%), thrombocytopenia (38%), and coagulation abnormalities (23%) appeared in neonatal CPSS. Twelve patients (75%) presented with congenital anomalies, of which congenital heart disease (CHD) (44%) was the most common. Thirteen patients with IPSS initially underwent conservative treatment, but two of them were recommended for the catheter interventional therapy and liver transplantation, respectively, due to progressive deterioration of liver function. Spontaneous closure occurred in nine patients with IPSS. The shunt was closed using transcatheter embolization in one patient with EPSS type II. Another patient with EPSS type II underwent surgical treatment of CHD firstly. The remaining patient with EPSS type Ib received medical therapy and refused liver transplantation. Conclusion: Hyperammonemia, neonatal cholestasis, elevated liver enzyme, hypoglycemia, and thrombocytopenia are the main complications of neonatal CPSS. Moreover, CPSS is associated with multiple congenital abnormalities, especially CHD. Intrahepatic portosystemic shunts may close spontaneously, and conservative treatment can be taken first. Extrahepatic portosystemic shunts should be closed to prevent complications.

Isomerism, also referred to as \"heterotaxy\" is a complex set of anatomic and functional perturbations. One of the most obvious manifestations of isomerism is the disturbance of organ arrangement, such that the thoracic organs are no longer asymmetric on the left and right. We report the case of a 14-year-old female in whom exercise-induced dyspnea led to a late diagnosis of left isomerism complicated by Abernethy malformation and portopulmonary hypertension. A comprehensive evaluation revealed two anatomic left lungs and hyparterial bronchi, bilateral left atria, an interrupted inferior caval vein with azygos continuation, multiple spleens, sinus node dysfunction, hepatic hypertrophy with focal nodular hyperplasia, and absence of the portal vein. Pulmonary vasodilator therapy was initiated resulting in clinical improvement. This case exhibits unique features including a late diagnosis of isomerism with Abernethy malformation and portopulmonary hypertension. The patient\'s presentation, medical workup, and future treatment emphasise the importance of multidisciplinary care in children with complex multisystem disease. We review the multiple cardiac and extracardiac manifestations of isomerism.

BACKGROUND: Abernethy syndrome is a congenital vascular anomaly in which the portal blood completely or partially bypasses the liver through a congenital portosystemic shunt. Although the number of recognized and reported cases is gradually increasing, Abernethy syndrome is still a rare disease entity, with an estimated prevalence between 1 per 30000 to 1 per 50000 cases. With this case series, we aimed to contribute to the growing knowledge of potential clinical presentations, course and complications of congenital portosystemic shunts (CPSS) in children.
METHODS: Five children are presented in this case series: One female and four males, two with an intrahepatic CPSS and three with an extrahepatic CPSS. The first patient, who was diagnosed with an intrahepatic CPSS, presented with gastrointestinal bleeding, abdominal pain and hyperammonaemia at six years of age. He underwent a percutaneous embolization of his shunt and has remained asymptomatic ever since. The second patient presented with direct hyperbilirubinemia in the neonatal period and his intrahepatic CPSS later spontaneously regressed. The third patient had pulmonary hypertension and hyperammonaemia due to complete portal vein agenesis and underwent liver transplantation at five years of age. The fourth patient was diagnosed immediately after birth, when evaluated due to another congenital vascular anomaly, and the last patient presented as a teenager with recurrent bone fractures associated with severe osteoporosis. In addition, the last two patients are characterised by benign liver nodules; however, they are clinically stable on symptomatic therapy.
CONCLUSIONS: Abernethy syndrome is a rare anomaly with diverse clinical features, affecting almost all organ systems and presenting at any age.

Diffuse pulmonary arteriovenous malformations or pulmonary arterial hypertension (PAH) may result from congenital portosystemic venous shunts. Hemangioma as a physical sign of congenital portosystemic shunts (like Abernethy syndrome) has not been described. I report two children (one with severe cyanosis from pulmonary arteriovenous malformations and the other with severe PAH) with cutaneous hemangioma and Abernethy syndrome. Hemangioma may be a clinical pointer to portosystemic shunts even in the absence of obvious liver disease.

Patients with congenital agenesis of the portal vein may develop hepatocellular tumors due to enhanced arterial blood flow. These tumors may be benign (FNH, adenomas) or malignant (hepatoblastoma, HCC). Liver resection can be proposed, and preoperative arterial embolization may decrease blood loss during surgery. Liver transplantation with PV reconstruction is also an option.

Abernethy syndrome (congenital extrahepatic portosystemic shunt (CEPS II)) as an etiology of hepatopulmonary syndrome (HPS) is uncommon. The severe hypoxemia and its consequences become incapacitating for the patient. Early shunt closure resolves hypoxemia and clinical symptomatology and prevents irreversible changes in pulmonary vasculature.