Abernethy malformation: beware in cases of unexplained hepatic encephalopathy in adults-case report and review of the relevant literature

A case of the Abernethy malformation: An exceptionally rare clinical entity

I review a case of a 30-year-old woman who presented with diarrhea, nausea and vomiting for several days. She was ultimately diagnosed with acute gastroenteritis but was incidentally found to have a congenital extrahepatic portosystemic shunt, also known as the Abernethy malformation. The Abernethy malformation, first described by Dr John Abernethy in the year 1793, is an exceptionally rare clinical entity.

The physiological implications of absent ductus venosus during fetal and post-natal life

Background

The ductus venosus (DV) is a pivotal component of fetal circulation. Absent DV (ADV) is associated with structural defects, portal vein (PV) anomalies, and chromosomal anomalies. This observational study aims to investigate the impact of ADV on fetal circulation and postnatal outcomes.

Materials and Methods

This observational study was conducted from August 2016 to January 2020 at a fetal and pediatric cardiac center. The DV was evaluated as part of routine fetal echocardiography. Cases of ADV were identified. Blood flow and exit points of the umbilical vein were studied. Cardiothoracic ratio, hydrops, and PV were assessed during the initial and follow-up scans. The postnatal evaluation included an ultrasound abdomen and computed tomography with triple-phase imaging to assess portosystemic shunts (PSSs). Serum ammonia levels were monitored.

Results

Twelve patients with ADV were identified. The median maternal age and median gestational age were 27.5 years and 22 weeks, respectively. Four patients had intrahepatic drainage, while eight had extrahepatic drainage. All patients (100%) exhibited cardiomegaly, but none developed hydrops. Four patients had persistent PSS postnatally. All four patients with PSS had asymptomatic hyperammonemia. Two patients underwent transcatheter closure of PSS. The intrahepatic variant showed good PV anatomy with no evidence of PSS.

Conclusions

DV evaluation should be performed during fetal echocardiography. ADV can lead to cardiomegaly and dilation of the right atrium and ventricle. PSS can be a potential sequela of the extrahepatic variant of ADV.

A rare presentation of type II Abernethy malformation and nephrotic syndrome: Case report and review

Type II Abernethy malformation is an extremely reported congenital extrahepatic portosystemic shunt in complication with nephrotic syndrome. We present the case of an 8-year-old boy who presented with symptoms of type II Abernethy malformation and nephrotic syndrome. This diagnosis of this type II Abernethy malformation was based on physical examination, blood tests, urinalysis, nephrotic and hepatic function tests, routine clinical lipid measurements, abdominal ultrasonography, and computed tomographic angiography. A kidney biopsy revealed the pathological features of nephrotic syndrome. This is the second reported patient diagnosed with type II Abernethy malformation and nephrotic syndrome. Captopril treatment was effective in improving the symptoms of this case. A patient with type II Abernethy malformation related to immune complex-mediated glomerular injury was effectively improved with medication. Type II Abernethy malformation is a causative factor of immune complex-mediated glomerular injury in nephrotic syndrome. Captopril treatment significantly improved the symptoms in this case.

Paediatric gastrointestinal and hepatobiliary radiology: why do we need subspecialists, and what is new?

We present the case for subspecialisation in paediatric gastrointestinal and hepato-pancreatico-biliary radiology. We frame the discussion around a number of questions: What is different about the paediatric patient and paediatric gastrointestinal system? What does the radiologist need to do differently? And finally, what can be translated from these subspecialty areas into everyday practice? We cover conditions that the sub-specialist might encounter, focusing on entities such as inflammatory bowel disease and hepatic vascular anomalies. We also highlight novel imaging techniques that are a focus of research in the subspecialties, including contrast-enhanced ultrasound, MRI motility, magnetisation transfer factor, and magnetic resonance elastography.

Embolization of congenital portosystemic shunt presenting after pediatric liver transplantation: Case report and literature review

This case report describes a 13-year 10-month-old girl who underwent a deceased-donor split LT for primary diagnosis of biliary atresia at the age of 12 months, who presented with a lower GI bleed. Ultrasound and CT revealed a venous vascular anomaly involving the cecum and ascending colon, with communication of the SMV and pelvic veins consistent with a CEPS. Associated varices were noted in the pelvis along the uterus and urinary bladder. These findings were confirmed by trans-hepatic porto-venography, which was diagnostic and therapeutic as a successful embolization of the CEPS was performed using micro-coils. There were no complications following the procedure and no further GI bleeding occurred, illustrating the efficacy of this treatment option for CEPS. We discuss the literature regarding the presenting complaint of GI bleeding post-LT, CEPS as a rare cause of GI bleeding and its association with PV, and the classification and treatment of CEPS.

Abernethy malformation and hepatocellular carcinoma: a serious consequence of a rare disease

Congenital portosystemic shunts (CPSS) are a rare vascular consequence of embryogenetic vascular alterations or the persistence of the fetal circulation elements, first described by John Abernethy in 1793 and classified by Morgan and Superina, into complete and partial portosystemic shunts. Its prevalence to this day has not been defined. We present a patient series of a 44-year-old and 47-year-old man and woman, with this rare congenital malformation and underlining hepatocellular carcinoma (HCC) treatment strategies. Over half of the individuals with CPSS have benign or malignant liver tumours, ranging from nodular regenerative hyperplasia, focal nodular hyperplasia, adenomas, HCC and hepatoblastomas. Additionally, it is known that half of individuals with Abernethy malformation type Ib will develop one or multiple types of tumours. There seems to be a direct association with tumorigenesis and CPSS, which is the primary consequence of absent portal flow. Surgery is the treatment of choice, either as a curative resection or orthotopic liver transplantation if recommended as per the criteria, in which replacing the hepatic parenchyma in the setting of an Abernathy malformation will correct the underlining hyper-arterialisation.

Abernethy malformation: Our experience from a tertiary cardiac care center and review of literature

Abernethy malformation, also called as congenital extrahepatic portosystemic venous shunt, is a rare anomaly involving the portal venous system. Although rare, it is increasingly being reported and is important to diagnose given the adverse clinical consequences in untreated patients. It has myriad of clinical presentations, from being completely asymptomatic to causing hepatic carcinoma, hepatic encephalopathy, severe pulmonary hypertension, and diffuse pulmonary arteriovenous malformation. We describe our experience with five cases in a tertiary pediatric cardiac care center with Abernethy malformation, with review of literature and also discuss possible therapeutic implications.