Congenital extrahepatic portosystemic shunt: an underdiagnosed but treatable cause of hepatopulmonary syndrome

Diagnosis and management of Abernethy syndrome

Abernethy syndrome (AS or extrahepatic portosystemic shunt) is an uncommon congenital malformation consisting of agenesis or hypoplasia of the portal vein (PV) in such a way that splanchnic venous blood drains directly into the systemic circulation through aberrant communications, resulting in a portosystemic shunt that bypasses the liver AS is an underdiagnosed condition with unknown incidence and complication rate given that symptoms are usually absent. AS identification is increasingly common because of improved imaging techniques, hence prognostic implications and clinical management need be understood. This editorial reviews the natural history of AS and its diagnostic-therapeutic implications, illustrating the process with a series of cases from our institution.

Abernethy Malformation Masquerading as Congenital Heart Disease: A Boy With Cyanosis, Clubbing, and Hypoxia

Abernethy malformation is an extrahepatic congenital portosystemic shunt characterized by the diversion of the portal blood away from the liver through a shunt that drains directly into the inferior vena cava. We present a case of a male child with Abernethy malformation, which was initially diagnosed as cyanotic heart disease due to pulmonary arteriovenous malformation. However, after proper clinical evaluation and investigations, the diagnosis of Abernethy malformation was established. Thereafter, the patient was successfully treated with endovascular embolization. At one year follow-up, marked relief in exertional dyspnea and improvement in physical growth was achieved with no observable complications.

Surgical shunt ligation for a congenital extrahepatic portosystemic shunt with pulmonary hypertension: A case report

Introduction and importance

Case presentation

Clinical discussion

Conclusion

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Congenital extrahepatic portosystemic shunt (CEPS) is a rare vascular malformation.

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Our patient had pulmonary hypertension due to CEPS.

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Pre- and intraoperative shunt occlusion tests were within acceptable limits.

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He underwent primary surgical portosystemic shunt ligation.

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No postoperative complications including acute portal hypertension occurred.

Endovascular Treatment of Congenital Portosystemic Shunt: A Single-Center Prospective Study

PURPOSE

To design a prospective study on endovascular closure of congenital portosystemic shunts. The primary endpoint was to assess the safety of endovascular closure. The secondary endpoint was to evaluate the clinical, analytical and imaging outcomes of treatment.

METHODS

Fifteen patients (age range: 2 days to 21 years; 10 male) were referred to our center due to congenital portosystemic shunts. The following data were collected prior to treatment: age, sex, medical history, clinical and analytical data, urine trimethylaminuria, abdominal-US, and body-CT. The following data were collected at the time of intervention: anatomical and hemodynamic characteristics of the shunts, device used, and closure success. The following data were collected at various post-intervention time points: during hospital stay (to confirm shunt closure and detect complications) and at one year after (for clinical, analytical, and imaging purposes).

RESULTS

The treatment was successful in 12 participants, migration of the device was observed in two, while acute splanchnic thrombosis was observed in one. Off-label devices were used in attempting to close the side-to-side shunts, and success was achieved using Amplatzer^™ Ductus-Occluder and Amplatzer^™ Muscular-Vascular-Septal-Defect-Occluder. The main changes were: increased prothrombin activity (p=0.043); decreased AST, ALT, GGT, and bilirubin (p=0.007, p=0.056, p=0.036, p=0.013); thrombocytopenia resolution (p=0.131); expansion of portal veins (p=0.005); normalization of Doppler portal flow (100%); regression of liver nodules (p=0.001); ammonia normalization (p=0.003); and disappearance of trimethylaminuria (p=0.285).

CONCLUSION

Endovascular closure is effective. Our results support the indication of endovascular closure for side-to-side shunts and for cases of congenital absence of portal vein.

Extracorporeal membrane oxygenation as rescue therapy in a pediatric liver transplant recipient with very severe hepatopulmonary syndrome

BACKGROUND

In children with cirrhosis, the prevalence of HPS ranges from 3% to 20%, resulting in impaired gas exchange due to alterations in pulmonary microvasculature. LT is the gold-standard cure for cirrhosis complicated by HPS and should ideally be performed prior to the development of severe HPS due to increased risk for post-transplant hypoxia, right heart failure, and outflow obstruction.

METHODS

We present a case of a 13-year-old man, who underwent pediatric LT for severe HPS complicated by postoperative respiratory collapse, requiring a 92-day course of veno-venous ECMO.

RESULTS

Post-transplant, despite BiPAP, inhaled nitric oxide and isoproterenol infusion, he remained hypoxic postoperatively and acutely decompensated on postoperative day 25, requiring veno-venous ECMO. After 84 days on ECMO, a persistent large splenorenal shunt was identified that was embolized by interventional radiology, and 8 days after shunt embolization and ASD closure, he was successfully weaned off ECMO.

CONCLUSIONS

This case describes the longest known duration of ECMO in a pediatric LT recipient and a unique improvement in hypoxemia following a portosystemic shunt closure. ECMO presents a heroic rescue measure for pediatric LT recipients with HPS that develops acute respiratory failure postoperatively refractory to alternative measures.

Presentation of Congenital Portosystemic Shunts in Children

Background: Congenital portosystemic shunts (CPSS) are rare vascular anomalies resulting in communications between the portal venous system and the systemic venous circulation, affecting an estimated 30,000 to 50,000 live births. CPSS can present at any age as a multi-system disease of variable severity mimicking both common and rare pediatric conditions. Case presentations: Case A: A vascular malformation was identified in the liver of a 10-year-old girl with tall stature, advanced somatic maturation, insulin resistance with hyperinsulinemia, hyperandrogenemia and transient hematuria. Work-up also suggested elevated pulmonary pressures. Case B: A young girl with trisomy 8 mosaicism with a history of neonatal hypoglycemia, transient neonatal cholestasis and tall stature presented newly increased aminotransferase levels at 6 years of age. Case C: A 3-year-old boy with speech delay, tall stature and abdominal pain underwent abdominal ultrasound (US) showing multiple liver nodules, diagnosed as liver hemangiomas by hepatic magnetic resonance imaging (MRI). Management and outcome: After identification of a venous malformation on liver Doppler US, all three patients were referred to a specialized liver center for further work-up within 12 to 18 months from diagnosis. Angio-computed tomography (CT) scan confirmed the presence of either an intrahepatic or extrahepatic CPSS with multiples liver nodules. All three had a hyperintense signal in the globus pallidus on T1 weighted cerebral MRI. Right heart catheterization confirmed pulmonary hypertension in cases A and C. Shunts were closed either using an endovascular or surgical approach. Liver nodules were either surgically removed if there was a risk of malignant degeneration or closely monitored by serial imaging when benign. Conclusion: These cases illustrate most of the common chief complaints and manifestations of CPSS. Liver Doppler US is the key to diagnosis. Considering portosystemic shunts in the diagnostic work-up of a patient with unexplained endocrine, liver, gastro-intestinal, cardiovascular, hematological, renal or neurocognitive disorder is important as prompt referral to a specialized center may significantly impact patient outcome.

Hepatopulmonary Syndrome and Portopulmonary Hypertension: Pulmonary Vascular Complications of Liver Disease

Pulmonary vascular disease is a frequent complication of chronic liver disease and portal hypertension, affecting up to 30% of patients. There are two distinct pulmonary vascular complications of liver disease: hepatopulmonary syndrome (HPS) and portopulmonary hypertension (POPH). HPS affects 25% of patients with chronic liver disease and is characterized by intrapulmonary vasodilatation and abnormal arterial oxygenation. HPS negatively impacts quality of life and is associated with a 2-fold increased risk of death compared to controls with liver disease without HPS. Angiogenesis, endothelin-1 mediated endothelial dysfunction, monocyte influx, and alveolar type 2 cell dysfunction seem to play important roles in disease pathogenesis but there are currently no effective medical therapies. Fortunately, HPS resolves following liver transplant (LT) with improvements in hypoxemia. POPH is a subtype of pulmonary arterial hypertension (PAH) characterized by an elevated mean pulmonary arterial pressure and pulmonary vascular resistance in the setting of normal left-sided filling pressures. POPH affects 5% to 6% of patients with chronic liver disease. Although the pathogenesis has not been fully elucidated, endothelial dysfunction, inflammation, and estrogen signaling have been identified as key pathways involved in disease pathogenesis. POPH is typically treated with PAH targeted therapy and may also improve with liver transplantation in selected patients. This article highlights what is currently known regarding the diagnosis, management, pathobiology, and outcomes of HPS and POPH. Ongoing research is needed to improve understanding of the pathophysiology and outcomes of these distinct and often misunderstood pulmonary vascular complications of liver disease. © 2021 American Physiological Society. Compr Physiol 11:1-22, 2021.

Clinical characteristics and therapeutic outcomes of pulmonary arterial hypertension secondary to congenital portosystemic shunts

The aim of this retrospective study was to investigate the clinical characteristics and therapeutic outcomes of pulmonary arterial hypertension (PAH) secondary to congenital portosystemic shunts (CPSS). Thirty-three pediatric patients diagnosed in our institution with CPSS between 2012 and 2019 were enrolled in this study. The patients were divided into PAH and non-PAH groups. The PAH group included 15 patients who presented with unexplained PAH when CPSS was diagnosed. Two patients with microangiopathic hemolytic anemia died of right heart failure shortly after diagnosis. One patient received a liver transplant at the age of 4.3 years and showed a mild decrease in pulmonary artery pressure (PAP) 4 years after the operation. Seven patients underwent one-stage shunt closure at a median age of 2.8 years (1.4-13 years). Follow-up examinations, from 1.6 to 4.1 years after intervention, showed marked reduction of PAP in one patient and stabilization of PAH in six others. However, in one patient who underwent two-stage shunt closure, a marked increase in PAP was noted after partial ligation of the shunt. The remaining four patients received only pulmonary vasodilator therapy, and one of them died of right heart failure 12 years after the PAH diagnosis. The non-PAH group included 18 patients without evidence of PAH upon CPSS diagnosis. Shunt closure was carried out in eight of these patients, but one patient subsequently developed PAH after the resolution of hepatopulmonary syndrome.Conclusion: CPSS may be a more likely cause of unexplained PAH in pediatric patients than previously thought. Shunt closure or liver transplantation may prevent the progression of PAH, or even improve it for the majority of CPSS patients.

Treatment Option for Abernethy Malformation-Two Cases Report and Review of the Literature

Background: Abernethy malformation is a rare vascular anomaly of the portal venous system, which is also known as congenital portosystemic shunts (CPSS). The clinical manifestations of this anomaly can be serious, including hepatopulmonary syndrome(HPS), which can lead to significant hypoxemia and cyanosis. Case Presentation: This study reports two cases of patients with Abernethy Malformation. Case 1 was a 6-year-old boy whose blood oxygen saturation was 78%. Case 2 was a 6-year-old girl who had a history of open heart surgery and residual cardiac left to right shunt, whose blood oxygen saturation was 83%. These two children had unexplained cyanosis and were diagnosed with pulmonary arteriovenous fistula by contrast echocardiography with agitated saline. A selective retrograde catheter angiography confirmed the presence of a portosystemic shunt. Case 1 was a type I Abernethy malformation and did not receive any specific treatment and could only wait for liver transplantation. Case 2 was with type II Abernethy and underwent transcatheter closure of the CPSS. A 20mm-diameter, 14mm-long Vascular Plug (SHSMA Inc, Shanghai, China) was used to occlude the shunt. Results: In case 1, the boy developed deteriorating cyanosis and dyspnea on exertion. In case 2, the exercise tolerance of the patient improved after shunt closure. During a follow-up of 3 years, her blood oxygen saturation increased from 83 to 98%. Conclusion: The results indicate that children with unexplained cyanosis require special attention since these patients may have Abernethy malformation, and part of them could be treated by transcatheter occlusion with a good outcome. The key to treatment is how it is diagnosed and carefully assessed.

Hyperandrogenism and malignant degeneration of hepatic adenomas in the setting of Abernethy malformation

Abernethy malformation refer to a congenital absence of intrahepatic portal veins leading to a primarily extrahepatic congenital portosystemic shunt. The lack of intrahepatic portal veins leads to a characteristic set of physical exam and imaging findings that may include hyperandrogenism and liver masses such as hepatic adenomas or focal nodular hyperplasia. In this case report, we describe a 20-year-old female who presented with an enlarging hepatic adenoma. A separate hepatic adenoma had previously been biopsied and noted to have undergone malignant degeneration into hepatocellular carcinoma. For each lesion, she was treated with combination transarterial embolization and microwave ablation. On follow-up imaging after therapy, it was then noted that her extrahepatic portal vein drained directly into the inferior vena cava, consistent with congenital portosystemic shunt. Recognition of this vascular anomaly is critical in treatment planning, as early intervention with either medical therapy or surgery can prevent the metabolic sequela of this unique constellation of symptoms.

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.

Congenital Extrahepatic Portosystemic Shunts (Abernethy Malformation): An International Observational Study

Congenital extrahepatic portosystemic shunt (CEPS) or Abernethy malformation is a rare condition in which splanchnic venous blood bypasses the liver draining directly into systemic circulation through a congenital shunt. Patients may develop hepatic encephalopathy (HE), pulmonary hypertension (PaHT), or liver tumors, among other complications. However, the actual incidence of such complications is unknown, mainly because of the lack of a protocolized approach to these patients. This study characterizes the clinical manifestations and outcome of a large cohort of CEPS patients with the aim of proposing a guide for their management. This is an observational, multicenter, international study. Sixty-six patients were included; median age at the end of follow-up was 30 years. Nineteen patients (28%) presented HE. Ten-, 20-, and 30-year HE incidence rates were 13%, 24%, and 28%, respectively. No clinical factors predicted HE. Twenty-five patients had benign nodular lesions. Ten patients developed adenomas (median age, 18 years), and another 8 developed HCC (median age, 39 years). Of 10 patients with dyspnea, PaHT was diagnosed in 8 and hepatopulmonary syndrome in 2. Pulmonary complications were only screened for in 19 asymptomatic patients, and PaHT was identified in 2. Six patients underwent liver transplantation for hepatocellular carcinoma or adenoma. Shunt closure was performed in 15 patients with improvement/stability/cure of CEPS manifestations. Conclusion: CEPS patients may develop severe complications. Screening for asymptomatic complications and close surveillance is needed. Shunt closure should be considered both as a therapeutic and prophylactic approach.

Pulmonary arteriovenous malformations in a patient with single ventricle and polysplenia syndrome

A 5-month-old girl with single ventricle, interrupted inferior vena cava and polysplenia syndrome palliated with bilateral Blalock-Taussig shunts developed severe cyanosis despite apparently increased pulmonary blood flow. Angiography revealed diffuse pulmonary arteriolar capillary dilatation and early pulmonary venous filling, suggesting the presence of pulmonary arteriovenous malformations. Abdominal angiography at 6 months demonstrated a large extrahepatic portosystemic shunt, which was percutaneously closed with a vascular plug. Kawashima operation was performed 2 weeks after portosystemic shunt closure. Although cyanosis improved temporarily, the patient suffered from deteriorating cyanosis at 9 months of age and underwent Fontan completion. Thereafter, her oxygen saturation gradually improved to 95% over the course of 3 weeks. Both the congenital extrahepatic portosystemic shunt and Kawashima operation contributed to the development of pulmonary arteriovenous malformations.

Congenital extrahepatic portosystemic shunt with progressive myelopathy and encephalopathy

Portosystemic encephalopathy commonly occurs in patients with portal hypertension caused by end-stage liver disease or portal vein thrombosis. Congenital extrahepatic portosystemic shunt (CEPS) is an underdiagnosed and treatable condition that can cause encephalopathy and various neuropsychiatric symptoms. We report an unusual case of type 2 CEPS in a 29-year-old woman who presented with progressive myelopathy and fluctuating encephalopathy on a background of congenital cardiac disease. Investigations showed hyperammonaemia, and despite no evidence of portal hypertension on ultrasound imaging, CT scan of abdomen showed a shunt between the mesenteric and left internal iliac veins. Patients with unexplained fluctuating or progressive neuropsychiatric symptoms should have their serum ammonia checked. A raised serum ammonia concentration without known portal hypertension should prompt further investigations for extrahepatic shunts.

Congenital Portosystemic Shunts: Current Diagnosis and Management

Congenital portosystemic shunts are increasingly recognized in several settings and at any age. The following are some of the most common presentations: prenatal ultrasound, neonatal cholestasis, incidental finding on abdominal imaging, or systemic complications such as unexplained cardiopulmonary or neurological disease, or the presence of liver nodules in a noncirrhotic liver. The purpose of the present review is to summarize clinical presentation and current recommendations for management, and highlight areas of future research. Illustrative examples from the veterinary literature complement our current lack of knowledge of this rare malformation often masquerading as a multisystem disease.

Abernethy malformation type 2: varied presentation, management and outcome

PURPOSE

To study the varied presentations and the outcomes in children with Type 2 Abernethy malformation following shunt ligation.

MATERIAL AND METHODS

Children with Type 2 Abernethy who had had been operated between 2013 and 2017 were included in the study. The diagnosis had been confirmed on ultrasonography, CECT or angiography. All patients underwent laparotomy. The shunt was identified, clamped and the bowel congestion was noted. The shunt was ligated if the bowel congestion was not significant or had improved. Relevant follow-up investigations were done to document the resolution or amelioration of symptoms and the patency of the shunt.

RESULTS

Five patients were included in the study with a median age of 6 years. Hepatopulmonary syndrome was the presentation in 4 patients while one patient presented with liver tumor. Ultrasonography and CECT were able to diagnose Type 2 malformation in 4 patients whereas in 1 patient the distal portal vein was not seen. The postoperative period was complicated in 3 patients. At the median follow up at 14 months, good intrahepatic portal flow in all patients. All patients demonstrated improvement/ resolution of symptoms.

CONCLUSION

Abernethy is rare malformation which can have a varied presentation. Additional investigations may be needed to confirm the diagnosis of Type 2 variety. Most patients have gradual improvement of symptoms.

LEVEL OF EVIDENCE

Level IV/ Treatment study.

A 10-year-old boy with dyspnea and hypoxia: abernathy malformation masquerading as pulmonary arteriovenous fistula

Background

Abernethy malformation is an extremely rare congenital malformation characterised by an extrahepatic portosystemic shunt. Children with Abernathy malformation can develop hepatopulmonary syndrome (HPS) with pulmonary arteriovenous fistulas (PAVF) or pulmonary hypertension. PAVF manifests as central cyanosis with effort intolerance. We report a case of PAVF in a Ten-year-old Boy. Persistent symptoms identified Abernathy malformation as the cause of progressive symptoms and current understanding of this rare malformation is reviewed.

Case presentation

A case of 10-year-old boy with Abernethy malformation complicated with HPS initially managed as PAVF was presented. Selective lung angiography showed a typical diffuse reticular pattern on right lower lung, which suggested PAVF. However, cyanosis was not improved post transcatheter coil embolization. Then, liver disease was considered although the patient had normal aspartate aminotransferase and alanine aminotransferase. The significantly elevated serum ammonia was attracted our attention. Abdominal computed tomography also exhibited enlarged main portal vein (MPV), cirsoid spleen vein, and superior mesenteric vein (SMV). Angiography with direct opacification of the SMV with a catheter coming from the inferior vena cava (IVC) and going to the SMV via the shunt vessel (SHUNT) between the MPV and IVC. Occlusion the IVC with an inflated balloon, injection of contrast medium via a catheter placed in the SMV, MPV was showed and absence of intrahepatic branches. Abernethy malformation IB type is finally confirmed.

Conclusions

Abernethy malformation is an unusual cause for development of PAVF and cyanosis in children. Clinicians must be suspicious of Abernethy malformation complicated with HPS. If patients have abnormal serum ammonia and enlarged MPV in abdominal CT, cathether angiography should be done to rule out Abernethy malformation.

Laparoscopic Partial Closure for Congenital Portosystemic Shunt-Indications, Postoperative Management, and Subsequent Complete Closure

Extrahepatic congenital portosystemic shunts (CPSSs) can be occluded by surgical or endovascular approaches. However, when the estimated portal vein (PV) pressure after the closure is high enough to induce symptoms associated with portal hypertension, partial closure is recommended to avoid life-threatening events. In this study, we attempted laparoscopic partial closure of a CPSS in two patients. Along with intraoperative real-time measuring of the PV pressure and angiography, laparoscopic partial closure was performed to achieve a PV pressure of ≤25 mmHg. Subsequently, the intrahepatic portal system grew in both patients. The partially ligated CPSS closed spontaneously in the first patient. In the second patient, laparoscopic complete closure was performed for the residual CPSS 6 months after the first operation. To our knowledge, this is the first report of laparoscopic partial closure for CPSS. Minimally invasive laparoscopic partial ligation of CPSS is technically feasible and useful when the estimated PV pressure is too high to tolerate one-step complete closure.

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.

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.

Congenital portosystemic shunts: diagnosis and treatment

Congenital portosystemic shunts (CPSS) are rare vascular malformations that create an abnormal connection between portal and systemic veins resulting in complete or partial diversion of the portal flow away from the liver to the systemic venous system. Different anatomic types exist and several classifications have been proposed. They can be associated with other malformations especially cardiac and heterotaxia. The main complications include hepatic encephalopathy, liver tumors, portopulmonary hypertension, and pulmonary arteriovenous shunts. Diagnosis relies on imaging, and prenatal diagnosis is possible. Spontaneous closure of the CPSS is possible in some anatomic forms during the first year of life. When the CPSS remains patent, radiologic or surgical closure of the CPSS may prevent, resolve, or stabilize complications. Interventional radiology plays a key role for both the preoperative evaluation with occlusion test to assess the exact anatomy and to measure portal pressure after occlusion of the CPSS. Endovascular closure is the first option for treatment when possible.

Congenital portosystemic venous shunt

Congenital portosystemic venous shunts are rare developmental anomalies resulting in diversion of portal flow to the systemic circulation and have been divided into extra- and intrahepatic shunts. They occur during liver and systemic venous vascular embryogenesis and are associated with other congenital abnormalities. They carry a higher risk of benign and malignant liver tumors and, if left untreated, can result in significant medical complications including systemic encephalopathy and pulmonary hypertension.

CONCLUSION

This article reviews the various types of congenital portosystemic shunts and their anatomy, pathogenesis, symptomatology, and timing and options of treatment. What is Known: • The natural history and basic management of this rare congenital anomaly are presented. What is New: • This paper is a comprehensive review; highlights important topics in pathogenesis, clinical symptomatology, and treatment options; and proposes an algorithm in the management of congenital portosystemic shunt disease in order to provide a clear idea to a pediatrician. An effort has been made to emphasize the indications for treatment in the children population and link to the adult group by discussing the consequences of lack of treatment or delayed diagnosis.

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

The Abernethy malformation consists of a congenital extrahepatic portosystemic shunt and is believed to be extremely rare in humans. The potential implications of abnormal portovenous shunting and decreased hepatic portal flow are numerous and potentially serious. Although congenital extrahepatic portosystemic shunts are increasingly suspected and diagnosed in specialized centres, much of their clinical presentation and natural history is not fully understood. Symptoms of portosystemic shunt are mainly caused by increased levels of ammonia, which lead to signs of encephalopathy. Therapeutic options depend on the type of shunt and its clinical course, so the classification of the congenital portosystemic shunt is a key finding in these patients.