Abernethy malformation: a case report

Congenital Extrahepatic Portosystemic Shunt Complicated by the Development of Hepatoblastoma: A Case Report and Review of Literature

Congenital portosystemic shunts (CPSS) or congenital extrahepatic portosystemic shunts (CEPS) is a rare malformation. This congenital anomaly presents with a diverse array of clinical manifestations, ranging from asymptomatic to severe complications such as cardiac failure, pronounced pulmonary hypertension, and widespread pulmonary arteriovenous malformations. CPSS increases the risk of developing benign or malignant liver tumors, including nodular regenerative hyperplasia, focal nodular hyperplasia, hepatic adenoma, hepatocellular carcinoma, and hepatoblastoma. We report a case of a 15-month-old boy, identified with Abernethy's malformation type Ib, who presented with an abdominal mass during a follow-up. A comprehensive assessment established a diagnosis of hepatoblastoma. The patient was transferred to a specialized liver transplant center for further treatment and management. This is a review of literature highlighting the complexity of Abernethy malformation and its associated risk of liver tumors.

An adolescent girl in Hong Kong with type Ib Abernethy malformation complicated by multiple focal nodular hyperplasia

Congenital portosystemic venous shunts are developmental anomalies. They represent portal communication with the systemic circulation. The pathogenesis is linked to the complexity of the embryological development of the inferior vena cava and portal vein. We reported a case of an asymptomatic 14-year-old Chinese adolescent girl in Hong Kong with a confirmed congenital portosystemic shunt type 1b. The condition can be diagnosed using contrast-enhanced CT scans and MRIs. Early recognition of the condition is important due to elevated risks of developing hepatocellular tumours. Liver transplantation may be considered curative.

A basic understanding of congenital extrahepatic portosystemic shunt: incidence, mechanism, complications, diagnosis, and treatment

Extrahepatic portosystemic shunt belongs to a family of rare vascular abnormalities. The clinical importance and manifestations of this vascular abnormality range from asymptomatic cases to liver or metabolic dysfunctions of various degrees. Congenital extrahepatic portosystemic shunt, also termed as Abernethy malformation, is a very rare congenital vascular malformation in which splenomesenteric blood drains into a systemic vein, bypassing the liver through a complete or partial extrahepatic shunt. So far, limited cases of congenital extrahepatic portosystemic shunt have been reported. In this review, incidence, mechanisms, complications, diagnoses and treatments of congenital extrahepatic portosystemic shunt are described.

An Interesting Case of Congenital Intrahepatic Porto-hepatic Shunt as a Cause of Unexplained Encephalopathy

Congenital portosystemic shunts can be divided into two types: intrahepatic shunts in which there is an abnormal connection between the branches of the portal vein and either the inferior vena cava or the hepatic veins and less commonly the extrahepatic type in which the portal system is connected to one of the branches of the mesenteric veins. Here we describe a 73-year-old woman who was admitted to the hospital with clinical evidence of encephalopathy and was found to have hyperammonemia. Abdominal computed tomography angiography was performed and revealed a dilated portal vein measuring up to 1.8 cm at the porta-hepatis along with dilated superior mesenteric and splenic veins. Multiple dilated vascular channels were identified within the right hepatic lobe. An intrahepatic portosystemic shunt between an enlarged middle hepatic vein and two separate branches of the right portal vein was demonstrated. A liver biopsy showed normal architecture with no evidence of inflammation or fibrosis. Portosystemic shunts are rare and often detected in adulthood but should be considered as an important cause of unexplained encephalopathy in the absence of cirrhotic liver disease or hepatic trauma. Given that the size of such shunts increases with age, older persons are more prone to the effect of toxic metabolites.This age-associated increase in shunt size may help explain why some patients remain asymptomatic until later in their life which may account for the late presentation in our patient.

A case report on an incidental discovery of congenital portosystemic shunt

RATIONALE

Congenital portosystemic shunt (Abernethy malformation) is a rare entity causing the portal blood to drain directly into the systemic circulation, eluding the liver. These shunts arise through disturbances in the embryonic development.

PATIENT CONCERNS

A 9-year-old male patient was referred to our department for further evaluation of a vascular malformation which was diagnosed in another facility when the patient was 2 years old, following a routine abdominal ultrasound. The patient had no complaints and the physical examination was normal at all times.

DIAGNOSIS

Laboratory tests and esogastroduodenoscopy were normal. The abdominal ultrasound showed a side-to-side shunt between a short portal trunk and the inferior vena cava. A hepatic mass suggestive for focal noduar hyperplasia was seen in the left liver lobe. Abdominal angio-computed tomography (angio-CT) was performed and the ultrasonographic anomalies were confirmed. Multiple other vascular malformations were diagnosed-hepatic artery emerging from the superior mesenteric artery, with early division; hepatic veins forming a short common trunk before draining into the inferior vena cava; supranumerary right renal artery emerging from the aorta, tributary for the upper renal pole. Ecocardiography showed left superior vena cava persistence. The final diagnosis was Abernathy malformation type IB. In the meantime the patient was diagnosed with allergic asthma.

INTERVENTIONS

No surgical cure was pursued because the malformation was an incidental discovery.

OUTCOMES

The patient was followed-up closely from the final diagnosis (when he was 9 years old) to present (he is currently 10 years old) with no change in his status-he remained asymptomatic.

LESSONS

Angio-CT should be the performed whenever a vascular malformation is suspected in order to establish a correct diagnosis, because portosystemic shunts carry a high risk of severe complications. Knowing that patients with portosystemic shunts may have pulmonary hypertension, respiratory complaints should be carefully evaluated-in this particular case, even though the most probable cause for the respiratory symptoms was pulmonary hypertension, it was ruled out by cardiac ultrasonography and further investigations confirmed the diagnosis of allergic asthma.

The Characteristics and Outcomes of Abernethy Syndrome in Korean Children: A Single Center Study

PURPOSE

Abernethy malformation is a rare condition, which was first described in 1793 as a congenital extrahepatic porto-systemic shunt (CEPS) directing splanchnic blood flow into the inferior vena cava. Eighty cases have been published so far that reported CEPS, while in Korea, very few cases have been reported. Through this study, we present 6 cases of patients diagnosed with CEPS at Samsung Medical Center and compare these with other such cases published in France and China.

METHODS

We reviewed clinical, laboratory, and imaging data of 6 children with CEPS in our pediatric clinic between 2004 and 2017.

RESULTS

A total of 6 children with CEPS was included in this study, namely, one with type 1a, two with type 1b, and three with type 2 CEPS. The most common presenting symptom was gastrointestinal bleeding (50.0%). Therapeutic interventions included shunting vessel ligation (16.7%) in type 2 CEPS and liver transplantation (16.7%) in type 2 CEPS patient with suddenly developed hepatic encephalopathy.

CONCLUSION

There is no consensus guideline for the optimal management of patients with CEPS. Large-sample studies regarding CEPS are needed to evaluate the characteristics of patients with CEPS and determine the treatment guideline for CEPS.

Living Donor Liver Transplantation for Unresectable Liver Adenomatosis Associated with Congenital Absence of Portal Vein: A Case Report and Literature Review

BACKGROUND

Abernethy malformation (AM), or congenital absence of portal vein (CAPV), is a very rare disease which tends to be associated with the development of benign or malignant tumors, usually in children or young adults.

CASE REPORT

We report the case of a 21-year-old woman diagnosed with type Ib AM (portal vein draining directly into the inferior vena cava) and unresectable liver adenomatosis. The patient presented mild liver dysfunction and was largely asymptomatic. Living donor liver transplantation was performed using a left hemiliver graft from her mother. Postoperatively, the patient attained optimal liver function and at 9-month follow-up has returned to normal life.

CONCLUSIONS

We consider that living donor liver transplantation is the best therapeutic solution for AM associated with unresectable liver adenomatosis, especially because compared to receiving a whole liver graft, the waiting time on the liver transplantation list is much shorter.

Congenital absence of the portal vein associated with focal nodular hyperplasia of the liver and congenital heart disease (Abernethy malformation): A case report and literature review

Abernethy malformation is a rare congenital malformation defined by an extrahepatic portosystemic shunt. The majority of affected patients are young (<18 years of age) and experience various symptoms, including vomiting, jaundice, dyspnea and coma. The current study presents a case of Abernethy malformation in an asymptomatic adult male patient. The patient exhibited congenital absence of the portal vein, congenital heart disease (postoperative ventricular septal defect status), and multiple liver lesions, confirmed to be focal nodular hyperplasia by biopsy. Ultrasonography and magnetic resonance imaging findings revealing the liver lesions, type II congenital absence of the portal vein and the portosystemic shunt are presented. In addition, the common clinical presentations, associated anomalies, diagnostic workup and treatment options of this disorder are investigated by reviewing 101 previously reported cases.