Congenital extrahepatic portosystemic shunt: description of four cases and review of the literature

Abernethy Malformation and Gastrointestinal Bleeding: A Case Report and Literature Review

Background: Congenital extrahepatic portosystemic shunt (CEPS), also termed Abernethy malformation (AF) is a rare anomaly of the splanchnic venous system. Several approaches, including shunt closures through surgical or radiological interventions and liver transplantations, have been proposed, but clear comparisons among different treatment strategies are still unavailable. Purpose: We report a case in which an unusual portosystemic shunt was present between the dilated inferior mesenteric vein (IMV) to the right ovarian vein. A mini literature review of AF patients presented with gastrointestinal (GI) tract bleeding. Research design: Case report and literature review. Data Collection: An electronic search of PubMed was performed from inception to December 2023. Results: 34 AF patients presented with GI tract bleeding were identified published in the literature. The proportion of type II AF patients presenting with GI bleeding is greater (79%). Conclusions: We regard that both surgical ligation and endovascular closure of the shunt are effective and safe treatments for these patients, but coils embolization alone may not be sufficient to completely close the shunt when the shunt flow is high.

Physiological and behavioural implications of the portosystemic shunt in C57Bl/6J mice

A significant fraction of the popular inbred C57Bl/6J mice show structural and biochemical features of the congenital portosystemic shunt (PSS). How this hepatic abnormality affects physiological and behavioural parameters has not been explored in detail. Here, we confirmed the frequent occurrence of the PSS in C57Bl/6J mice by three different methods. We screened a cohort of 119 C57Bl/6J mice for total bile acids (TBA) in plasma, identified 11 animals (9.2%) with high TBA (>11 µm; 171.1 ± 76.8 µm), and confirmed PSS presence in that subset by magnetic resonance angiography and 1H-magnetic resonance spectroscopy of brain metabolites in the hippocampal area. In addition to the high glutamine and low myo-inositol levels, we detected lower levels of several neurotransmitters and metabolites in the hippocampus, higher brain weight and volume, as well as enhanced brain glucose utilisation in the PSS mice. We also observed differences in peripheral organ weights, haematological cell counts and clinical chemistry parameters in C57Bl/6J mice with and without PSS. Animals with PSS were slightly hyperlocomotive, had better balance on the rotarod, showed altered gait properties, and displayed attenuated fear memory in the fear conditioning test. Furthermore, we revealed a significant alteration of the pharmacokinetic profile of diazepam in C57Bl/6J mice with PSS. Our data support previous reports of hepatic disturbances and demonstrate an altered neurobiological phenotype in C57Bl/6J mice with PSS. Such congenital differences between inbred C57Bl/6J littermates may significantly distort experimental outcomes of pharmacological, behavioural and genetic studies. KEY POINTS: A significant proportion of C57Bl/6J mice, an inbred strain popular in preclinical research, have congenital portosystemic shunts (PSS) that allow venous blood to enter systemic circulation bypassing the liver. In this study, we extended existing knowledge of PSS consequences, particularly with respect to the effects on brain structure and function. We demonstrated that C57Bl/6J mice with PSS differ from their normal counterparts in brain size and contents of several neuroactive substances, as well as in peripheral organ weights, rate of glucose utilisation, blood cell counts and blood clinical chemistry parameters. C57Bl/6J mice with PSS showed altered locomotor behaviour, performed worse in a memory test and had abnormal blood pharmacokinetics of a benzodiazepine drug after a single administration. PSS presence may significantly complicate the interpretation of experiments in C57Bl/6J mice; therefore, we propose that before their use in biomedical studies, these mice should be screened with a simple blood test.

Twelve-year review of galactosemia newborn screening in Taiwan: Evolving methods and insights

Background

Galactosemia was introduced into Taiwan's routine newborn screening (NBS) program in 1985. This study presents a 12-year experience, emphasizing disease diagnosis and screening performance.

Method

NBS for galactosemia utilized dried blood spot samples taken 48-72 h post-delivery, with total galactose (TGal) level as the primary marker. Newborns with critical TGal levels were referred immediately, while those with borderline TGal underwent a recall test. GALT activity measurement was applied simultaneously as the second-tier marker. Further confirmatory tests, such as whole exome sequencing (WES), were conducted upon referral.

Results

From January 1st, 2011, to December 31st, 2022, 51 cases were identified from 817,906 newborns. Of these, nine individuals had persistently elevated TGal. Diagnoses included one case of GALT deficiency, one of GALM deficiency, and seven of GALE deficiencies. Notably, the classic galactosemia patient (GALT deficiency) presented with extreme high TGal and was referred to the hospital for diet management immediately. All affected patients were instructed to adopt a galactose-restricted diet. By the median age of 2.5 years, all exhibited normal development and liver function.

Conclusion

The incidence of classical galactosemia and its variants is extremely low in Taiwan. Incorporating WES into NBS has improved our ability to detect various galactosemia forms, enriching our understanding of the genetic underpinnings. While these newly discovered forms often present with milder initial elevations in TGal, specific biochemical investigations and regular monitoring are essential to understanding the long-term implications and outcomes.

Percutaneous sequential closure of an Abernethy malformation: A case report

Abernethy malformation (congenital extrahepatic portosystemic shunt [CEPS]) is rare and is characterized by an aberrant connection between the portal and systemic veins, bypassing the liver. It can have varying presentations and can lead to severe complications if left untreated. It is usually diagnosed incidentally on abdominal imaging. Occlusion venography and measurement of portal pressures (pre- and postocclusion) is an important step in management. Complete occlusion of the malformation in cases where the portal veins in the liver are very small and the gradient is more than 10 mm Hg, can potentially lead to acute portal hypertensive complications, such as porto-mesenteric thrombosis. We report a case of Abernethy malformation diagnosed on an abdominal computed tomography scan that presented with neurological symptoms and was successfully managed by interventional radiology via endovascular closure through placement and sequential occlusion of 2 metal stents.

Rare portal hypertension caused by Abernethy malformation (Type IIC): A case report

BACKGROUND

Abernethy malformation is a rare congenital vascular malformation with a portosystemic shunt that may clinically manifest as cholestasis, dyspnea, or hepatic encephalopathy, among other conditions. Early diagnosis and classification are very important to further guide treatment. Typically, patients with congenital portosystemic shunts have no characteristics of portal hypertension. Herein, we report an 18-year-old female with prominent portal hypertension that manifested mainly as rupture and bleeding of esophageal varices. Imaging showed a thin main portal vein, no portal vein branches in the liver, and bleeding of the esophageal and gastric varices caused by the collateral circulation upwards from the proximal main portal vein. Patients with Abernethy malformation type I are usually treated with liver transplantation, and patients with type II are treated with shunt occlusion, surgery, or transcatheter coiling. Our patient was treated with endoscopic surgery combined with drug therapy and had no portal hypertension and good hepatic function for 24 mo of follow-up.

CASE SUMMARY

This case report describes our experience in the diagnosis and treatment of an 18-year-old female with Abernethy malformation type IIC and portal hypertension. This condition was initially diagnosed as cirrhosis combined with portal hypertension. The patient was ultimately diagnosed using liver histology and subsequent imaging, and the treatment was highly effective. To publish this case report, written informed consent was obtained from the patient, including the attached imaging data.

CONCLUSION

Abernethy malformation type IIC may develop portal hypertension, and traditional nonselective beta-blockers combined with endoscopic treatment can achieve high efficacy.

Congenital Absence of the Portal Vein as a Rare Cause of Portopulmonary Hypertension-A Case Study Series

Background. Congenital absence of the portal vein (CAPV) is an extremely rare malformation that is caused by aberrant venous development during embryogenesis and is usually associated with congenital portosystemic shunts (CPSS). This hemodynamic allows mesenteric blood to bypass the liver metabolism and causes an imbalance between vasodilators and vasoconstrictors in the pulmonary circulation, which, again, might lead to the development of secondary portopulmonary hypertension (PoPH). Establishing the exact morphology of the splanchnic venous system is important when evaluating possible therapeutic options (differentiating type I and II CAPV), because some variants enable the closure of the shunt, and this represents a potential cure for pulmonary arterial hypertension (PAH). Once PoPH is diagnosed, complex care in a specialized expert centre is necessary. If possible, CPSS closure is recommended. For long-term successful patient management, specific targeted PAH therapy administration is crucial. Significant morbidity and mortality in these patients may result not only from PAH itself but also due to specific PoPH complications, such as compression of the left main coronary artery by pulmonary artery aneurysm. Case Report. We report on two patients with PoPH due to CAPV and CPSS (without any liver disease) who presented as severe PAH and who, before admission to our expert centre, were misdiagnosed as idiopathic PAH. The case reports also represent our experience with respect to the long-term follow-up and PAH-specific medical treatment of these patients, as well as the possible (even fatal) complications of these rare and complex patients.

A new variant of Abernethy malformation treated by transhepatic interventional closure: a case report

Background

Congenital portosystemic shunts (CPSS) are rare vascular malformations and can be classified into extrahepatic and intrahepatic shunts. Extrahepatic CPSS, also termed Abernethy malformations are associated with severe long-term complications including portopulmonary hypertension, liver atrophy, hyperammoniemia and hepatic encephalopathy. We report a hitherto undescribed variant of Abernethy malformation requiring an innovative approach for interventional treatment.

Case presentation

We describe a 31-year-old patient following surgical repair of atrioventricular septal defect at the age of 6 years. In the long-term follow-up he showed persistent pulmonary hypertension which deteriorated despite dual pulmonary vasodilative treatment. When he developed arterial desaturation and symptomatic hyperammoniemia detailed reassessment revealed as underlying cause a hitherto undescribed variant of Abernethy malformation connecting the portal vein with the right lower pulmonary vein. Following interdisciplinary discussions we opted for an interventional approach. Since the malformation was un-accessible to interventional closure via antegrade venous or retrograde arterial access, a transhepatic percutaneous puncture of the portal vein was performed. Temporary balloon occlusion of the malformation revealed only a slight increase in portal venous pressure. Interventional occlusion of the large vascular connection was achieved via this transhepatic approach by successive implantation of two large vascular occluding devices. The postinterventional course was unremarkable and both ammonia levels and arterial saturation normalized at follow-up of 12 months.

Conclusions

Portal vein anomalies should be included in the differential diagnoses of pulmonary hypertension or pulmonary arterio-venous malformations. Based on careful assessment of the anatomy and testing of portal vein hemodynamics interventional therapy of complex Abernethy malformations can be performed successfully in specialized centers.

Angiographic diagnosis for accurate assessment of congenital porto-systemic shunt and extrahepatic portal vein obstruction in children

BACKGROUND

Congenital porto-systemic shunt (CPSS) is a rare disease and can cause fatal complications. Accurate angiographic assessment is mandatory for proper treatment. Although technically difficult, we developed assessment techniques and assessed their accuracy. One technique came from evaluating patients with extrahepatic portal vein obstruction (EHPVO).

METHODS

We conducted a single center retrospective study to evaluate the efficacy of angiographic diagnostic procedure for the assessment of CPSS and EHPVO, and its impact on patients' subsequent interventions and clinical course. Eight patients with CPSS and two patients with EHPVO who underwent diagnostic angiography were included. Assessment of the intrahepatic portal vein was performed in all patients. The route of the shunt, and portal vein pressure under shunt occlusion, were also evaluated for patients with CPSS. Evaluation was first attempted with a balloon angiographic catheter (standard method). Three additional techniques were performed as needed: (i) direct wedge-catheter injection without balloon inflation, (ii) use of occlusion balloon in two patients, and (iii) hybrid angiography with sheath placement directly into the superior mesenteric vein.

RESULTS

The standard method was sufficient in four patients. On the other hand, all three techniques were required in two patients each. One lost contact during follow up, but all other patients underwent optimal intervention. There were no complications related to the angiographic procedure.

CONCLUSIONS

Use of direct wedge-catheter injection without balloon inflation, occlusion balloon, and hybrid catheterization improved the diagnostic yield in patients with CPSS or EHPVO.

Abernethy Malformation Type II in a 70-Year-Old Patient with Angina Pectoris

Congenital extrahepatic portosystemic shunts (ECPSS) are rare developmental anomalies in which a variable portion of the portal blood bypasses the liver and is shunted in the systemic circulation via one or more aberrant vessels. We present a clinical case of a 70-year-old man, who was referred to the Cardiology Department because of exertional dyspnea, fatigue, and feeling of heaviness and pressure behind the sternum. MDCT of the aorta was performed and an aberrant vessel was discovered with communication with the left iliac vein on one side and superior mesenteric and splenic veins on the other. The portal vein was hypoplastic. The radiologic findings were suggestive of malformation of Abernethy. The ECPSS can be classified into 2 main groups (with complete and partial shunting). The patients have different clinical presentation. Some of them are completely asymptomatic while in others the shunt can manifest even before birth as fetal growth retardation or in the early neonatal period with neonatal cholestasis and galactosemia. Common complications are hepatic encephalopathy and hepatopulmonary syndrome and there is a wide variety of concomitant abnormalities. The imaging modalities play a crucial role in the diagnosis, classification, follow-up and the proper choice of therapeutic management in patients with ECPSS.

Abernethy syndrome in Slovenian children: Five case reports and review of literature

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.

CASE SUMMARY

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.

CONCLUSION

Abernethy syndrome is a rare anomaly with diverse clinical features, affecting almost all organ systems and presenting at any age.

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.

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.