Aetiology and management of extrahepatic portal vein obstruction in children: King's College Hospital experience

Esophagogastric Varix Caused by Extrahepatic Portal Vein Obstruction with Essential Thrombocythemia: A Case Report

Extrahepatic portal vein obstruction (EHPVO) is a rare disease-causing form of portal hypertension. Myeloproliferative neoplasm (MPN) including essential thrombocythemia (ET) is a reported risk factor for EHPVO due to underlying persistent thrombophilia. A Japanese woman in her 40s was referred to our hospital with a 1-month history of gastric variceal bleeding due to EHPVO. Laboratory investigation showed thrombocytosis despite portal hypertension. She had a mutation in clonal marker JAK2V617F with EHPVO, which prompted us to consult a hematologist. A bone marrow biopsy revealed megakaryocyte lineage proliferation, which confirmed a diagnosis of ET. Esophagogastroduodenoscopy revealed esophagogastric varices (LsF2CbRC2, Lg-cF1RC1), and abdominal computed tomography and angiography revealed splenomegaly and portal vein thrombosis with cavernous transformation, which suggested EHPVO. The patient had a history of ruptured esophagogastric varices and required prophylaxis against further variceal bleeding before antithrombotic therapy for EHPVO with ET. We performed laparoscopic Hassab's operation followed by endoscopic variceal ligation (EVL) and hematological cytoreduction therapy. Laparoscopic Hassab's operation and three bi-monthly EVL procedures improved the esophagogastric varix (LmF0RC0, Lg-f F0RC0) at 6 months after surgery. Cytoreduction therapy reduced platelet count to 60.1 × 104/uL, and the patient was very healthy at 7 months after surgery. Patients with EHPVO are traditionally referred to a gastroenterologist for abdominal pain, intestinal bleeding, or refractory ascites; however, hypercoagulative disease may be occult in such patients and require the attention of a hematologist. When treating patients with EHPVO, gastroenterologists should screen for hematological disease, including MPN.

Guidelines for the diagnosis and treatment of idiopathic portal hypertension, extrahepatic portal obstruction, and Budd-Chiari syndrome in Japan

This is the English version of the guidelines for the diagnosis and treatment of idiopathic portal hypertension, extrahepatic portal obstruction, and Budd-Chiari syndrome, which were established and revised in 2018 by the Aberrant Portal Hemodynamics Study Group under the jurisdiction of the Ministry of Health, Labor, and Welfare in Japan. These guidelines are excerpts, and the full version consists of 86 clinical questions and explanations, totaling 183 pages in Japanese.

Extrahepatic Portal Vein Obstruction in Children

OBJECTIVES

Extrahepatic portal vein obstruction is the most common cause of portal hypertension in children. This study aimed to evaluate the causes, clinical, laboratory and endoscopic findings, treatment approaches, long-term results, and prognosis of extrahepatic portal vein obstruction in children.

MATERIALS AND METHODS

We retrospectively evaluated 82 patients who were followed up with the diagnosis of extrahepatic portal vein obstruction at Gazi University Pediatric Gastroenterology clinic between January 1, 2011, and October 31, 2021.

RESULTS

Among our patients, 58.5% were male, median age at presentation was 36 months (range, 1 month to 6 years), and the follow-up period was 2 years (range, 1-14 years). The most common reasons for admission were gastrointestinal bleeding and splenomegaly. All patients diagnosed with incidentally detected obstruction were children under 5 years of age. The most frequently detected risk factors were history of umbilical vein catheterization (50%) and presence of procoagulant status (31%). Esophageal varices (94.8%), variceal bleeding (73.2%), hypersplenism (64.6%), and growth failure (13.4%) were the most common complications. Weight and/or height z-scores were lower in children with esophageal varices, variceal bleeding, and hypersplenism. Endoscopic treatments were more frequently applied to those with splenomegaly, thrombocytopenia, red color sign, and esophageal variceal bleeding. Rates of splenomegaly, hypersplenism, esophageal variceal bleeding, advanced varicose veins, and portal biliopathy were higher in patients who underwent portosystemic shunt surgery than in patients who did not undergo it.

CONCLUSIONS

Morbidity and mortality rates of variceal bleeding in extrahepatic portal vein obstruction were lower than bleeding seen in cirrhotic prehepatic portal hypertension. In our study, no patients died from extrahepatic portal vein obstruction-related complications. One patient died from tuberculous meningitis.

Wedged hepatic vein portovenography for assessment of Rex vein patency in children with extrahepatic portal venous obstruction

BACKGROUND

Meso-Rex bypass is the surgical intervention of choice for children with extrahepatic portal vein obstruction (EHPVO). Patency of Rex vein, umbilical recessus of the portal vein, is a prerequisite for this surgery. Conventional diagnostic modalities poorly detect patency, while transjugular wedged hepatic vein portography (WHVP) accurately detects patency in 90%.

OBJECTIVES

We aimed to assess Rex vein patency and portal vein branching pattern in children with EHPVO using transjugular WHVP and to identify factors associated with Rex vein patency.

METHODS

Transjugular WHVP was performed in 31 children with EHPVO by selective cannulation of left and right hepatic veins. Rex vein patency, type of intrahepatic portal venous anatomy (Types A-E), and factors associated with patency of Rex vein were studied.

RESULTS

The patency of Rex recess on transjugular WHVP was 29%. Complete obliteration of intrahepatic portal venous radicles was the commonest pattern (Type E, 38.7%) while Type A, the favorable anatomy for meso-Rex bypass, was seen in only 12.9%. Patency of the Rex vein, but not the anatomical pattern, was associated with younger age at evaluation (patent Rex: 6.6 ± 4.9 years vs. nonpatent Rex: 12.7 ± 3.9 years, p = 0.001). Under-5-year children had a 12 times greater chance of having a patent Rex vein (odds ratio: 12.22, 95% confidence interval: 1.65-90.40, p = 0.004). Patency or pattern was unrelated to local factors like umbilical vein catheterization, systemic thrombophilia, or disease severity.

CONCLUSION

Less than one-third of our pediatric EHPVO patients have a patent Rex vein. Younger age at evaluation is significantly associated with Rex vein patency.

A rare delayed onset of esophageal varices and portal vein thrombosis in a ten-year-old patient following umbilical vein catheterization

Introduction and significance

Portal vein thrombosis (PVT) is not commonly observed in patients, particularly those who have gone through neonatal intensive care unit (NICU) stays and had umbilical catheters. Although PVT can potentially cause hypertension and gastrointestinal bleeding it is highly unusual for this condition to manifest during childhood.

Case presentation

The authors present a case of a 10-year-old child who developed portal hypertension, esophageal varices, and multiple thrombophilia associated mutations. This child was born prematurely. Had to stay in the NICU, where an umbilical venous catheter was used which likely triggered the development of PVT. At the age of 7 he started experiencing distension, anemia and low platelet count, which eventually led to splenectomy. On at the age of 10 he began experiencing episodes of bleeding. Was diagnosed with esophageal varices and portal gastropathy. Through procedures, like Histoacryl glue injection and band ligation bleeding was successfully controlled. Genetic analysis revealed mutations associated with thrombophilia.

Clinical discussion

This case highlights how rare it is for older children to develop PVT and emphasizes the possibility of delayed onset symptoms following catheterization. The placement of catheters in NICUs can disrupt blood flow and increase the likelihood of clot formation. The presence of hypertension resulting from PVT can lead to complications such as varices. Effective control, over bleeding was achieved through interventions.Importantly, the presence of ACE I/D, FXIII Val34Leu, and Factor V Leiden mutations introduces an aspect to this scenario. It is worth noting that these mutations are not commonly linked to thrombophilia or clotting disorders.

Conclusion

This case highlights pediatric PVT, emphasizing the need for a collaborative approach among gastroenterologists, hematologists, and geneticists. Further research is required to understand PVT mechanisms and long-term implications, aiding in diagnosis and management, especially when it appears in late childhood. Evaluation is crucial in deciphering thrombophilia-related complications in the context of hypertension.

A high rate of post thrombotic complication in pediatric portal vein thrombosis

INTRODUCTION

Portal vein thrombosis (PVT) is a rare disease in children and may be complicated by portal hypertension (PH), hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPHTN) but their incidence and risk factors are unknown.

METHODS

An observational, retrospective cohort study of all consecutive children (≤18 years) with PVT treated at the Emma Children's Hospital Amsterdam University Medical Centers between January 1996 and January 2022 was conducted to identify the incidence and risk factors of these post thrombotic complications (PTC) in pediatric patients.

RESULTS

In total 43/ 703 thrombosis patients had PVT (boys 72.1 %; mean age 1.3 ± 0.5 years). Overall, 51 % of patients developed PH (n = 22), complicated by PPHTN in one of them. In 16 of 22 patients, PVT presented with portal hypertension. Clinically relevant bleeding due to portal hypertension occurred in 13 (59.1 %) patients with PH. The mean age at the first clinically relevant bleeding was 5.1 ± 5.9 years. Risk factors for the development of PH were lack of complete thrombus resolution (OR 24.3, 95 % CI 1.2-7.0; p = 0.008) and unprovoked VTE (OR, 35.4; 95 % CI 1.4-6.3; p = 0.012). Median time from PVT to PH was 137 days (range: 0 days to 5.04 years).

CONCLUSION

We demonstrated that half of the patients develop PH after PVT, with a lack of thrombus resolution and unprovoked VTE as independent risk factors. This high incidence underlines the importance of long-term standardized follow-up of patients after PVT and standard screening in patients at risk of PTC.

Portal Hypertension in Children: A Tertiary Center Experience in Turkey

Purpose

Portal hypertension (PH) and its complications have a significant impact on morbidity and mortality. This study aimed to evaluate the etiology; clinical, laboratory, and endoscopic findings; treatment approaches; long-term outcomes; and prognosis of pediatric PH.

Methods

This retrospective study included 222 pediatric patients diagnosed with PH between 1998 and 2016, and data encompassing clinical, laboratory, and radiological features; treatments; and complications were analyzed.

Results

The most common causes of PH were portal vein thrombosis (20.3%), progressive familial intrahepatic cholestasis (18.9%), and biliary atresia (12.2%). Among the enrolled patients, 131 (59.0%) were included in the cirrhotic group and 91 (41.0%) in the non-cirrhotic group. Hepatomegaly and increased transaminase levels were more frequent in the cirrhotic group than in the non-cirrhotic group. Additionally, portal gastropathy, esophageal varices, and variceal bleeding were more frequent in the non-cirrhotic group, whereas ascites, hepatopulmonary syndrome and hepatic encephalopathy were more common in the cirrhotic group. The incidence of hepatomegaly was higher in the presinusoidal group than in the prehepatic group (p<0.001). Hyperbilirubinemia was more frequent in the prehepatic group (p=0.046). The frequency of esophageal varices was similar between the prehepatic and presinusoidal groups; however, variceal bleeding was more frequent in the prehepatic group (p=0.002).

Conclusion

Extrahepatic portal vein obstruction, genetic-metabolic diseases, and biliary atresia were the most prevalent causes of PH in our country. In patients with PH, hepatomegaly, increased transaminase levels, and synthesis dysfunction were suggestive of cirrhotic PH. Notably, PH in patients without cirrhosis might be more severe than that in those with cirrhosis.

[A rare case of neonatal-onset hepatic sinusoidal obstruction syndrome]

A male infant, aged 1 month and 14 days, was admitted to the hospital due to abdominal distension lasting for 2 weeks and worsening for 3 days. The infant had a history of omphalitis. Physical examination revealed severe abdominal distension, prominent abdominal wall veins, hepatosplenomegaly, and massive ascites. There was a slight elevation in liver transaminase levels. Liver ultrasound and CT scans demonstrated the absence of visualization of the intrahepatic segment of the portal vein and the left, middle, and right veins of the liver, indicating occlusion of these vessels, along with surrounding fibrous hyperplasia. The clinical diagnosis was hepatic sinusoidal obstruction syndrome resulting from omphalitis. A large amount of bloody ascites developed after 12 days of hospitalization, resulting in hypovolemic shock and respiratory failure. The infant passed away following the family's decision to discontinue treatment. This article focuses on the diagnostic approach and multidisciplinary management of neonatal-onset hepatic sinusoidal obstruction syndrome, as well as provides insights into the differential diagnosis of hepatomegaly and ascites.

Gastrointestinal Bleeding in Children: Current Management, Controversies, and Advances

Upper gastrointestinal bleeding (UGIB) in children has many causes, with its prevalence varying by age. Often presenting as hematemesis or melena, the initial treatment is stabilization of the patient, including protection of the airway, fluid resuscitation, and a transfusion hemoglobin threshold of 7 g/L. Endoscopy should be performed with the goal of using combinations of therapies to treat a bleeding lesion, generally involving epinephrine injection along with either cautery, hemoclips, or hemospray. This review discusses the diagnosis and treatment of variceal and non-variceal gastrointestinal bleeding in children with a focus on current advances in the treatment of severe UGIB.

Angiographic patterns of portal venous system in children with extrahepatic portal hypertension and its etiological and clinical relevance

PURPOSE

To study the relationship between the angiographic pattern of extrahepatic portal vein obstruction (EHPVO) and its etiology and clinical manifestations.

METHODS

Clinical, etiological, and angiographic findings in 155 children with EHPVO were reviewed. Anatomy of extrahepatic portal venous system (EPVS) was categorized into five imaging patterns. Assessment of the severity of esophageal and gastric varices (EV and GV) was performed by upper gastrointestinal endoscopy.

RESULTS

Based on multislice CT angiography, most commonly observed pattern of EHPVO was type I (48.4%) and type II (29%). According to anamnesis, 68 (43.8%) children had pathological conditions in neonatal period. Of these, 35 (22.6%) had an umbilical vein catheterization, 11 (7.1%) had a history of omphalitis, and 9 (5.8%) had prolonged jaundice. Thirteen (8.4%) patients had various septic conditions in neonatal period and it was more common associated with widespread thrombosis throughout the EPVS (type 5)-28% of observations. Significantly lower risk of bleeding from EV (p = 0.01) was noted in children with type IV pattern, whereas children with type III and V patterns had higher grades of EV.

CONCLUSION

Angiographic pattern of portomesenteric occlusion may provide a clue to its etiology, and clinical manifestation, especially in children with widespread thrombosis throughout the EPVS.

A rare case of duodenal variceal bleeding due to extrahepatic portal vein obstruction successfully treated with endoscopic injection sclerotherapy

Primary extra-hepatic portal vein obstruction (EHPVO) is a disease that develops ectopic varices due to portal hypertension and obstruction of the portal vein. Since bleeding from ectopic varices is life-threatening, the management of ectopic varices is important for patients with primary EHPVO. Here, we report a case of duodenal variceal bleeding in a patient with primary EHPVO. A 39-year-old man was diagnosed with F2-shaped duodenal varices (DV) due to primary EHPVO and was first treated with endoscopic variceal ligation for temporary hemostasis. We then performed angiography to understand the detailed hemodynamics and subsequently conducted endoscopic injection sclerotherapy (EIS) with a sclerosing agent containing N-butyl-2-cyanoacrylate for further hemostasis. After the treatment, dynamic computed tomography and endoscopic ultrasound revealed that the blood flow to the causative DV disappeared, although the DV itself remained. The patient was discharged without any re-bleeding or adverse events. Since treatment for DV due to primary EHPVO differs depending on hemodynamics (hepatofugal or hepatopetal blood flow), evaluating detailed hemodynamics for optimal treatment selection is crucial. Although EIS for this patient was not a radical treatment, it was effective in managing acute bleeding from the DV. This case will serve as a reference for successful treatment in future cases.

Young boy with a long history of splenomegaly and cytopenia

A 15-year-old boy was admitted with a history of cytopenia (white blood cell count 3.170/μm, platelets 90.000/μm) associated with splenomegaly, found during investigations for recurrent mild jaundice due to Gilbert's syndrome.He was in good general health, without systemic symptoms; therefore, the leading causes of asymptomatic splenomegaly were excluded. Coagulation, liver tests and abdomen ultrasound (US) were normal, showing a hepatopetal portal flow to the colour-Doppler. There was no sign of haemolysis on haematology investigations. The C reactive protein, immune globulins levels and erythrocyte sedimentation rate were normal, excluding both an infective and an immune regulation disorder. We excluded the haematological malignancy and lymphoproliferative disorders through a peripheral blood smear and a bone marrow biopsy.His history was remarkable for neonatal sepsis, which required umbilical venous catheter during hospitalisation in a neonatal intensive care unit (NICU). The patient follow-up was interrupted for a while, probably due to his good health condition.At age 17 years, the child accessed our emergency department. for a minor trauma to the limbs, and his physical examination was unremarkable, except for the splenomegaly. We repeated the abdomen US, with colour flow Doppler (figure 1).

Optimal Treatment for Patients With Cavernous Transformation of the Portal Vein

Cavernous transformation of the portal vein (CTPV) is a sequela of extrahepatic and/or intrahepatic portal vein obstruction caused by a combination of local and risk factors. It was ever taken as a relatively rare disease due to its scant literature, which was mainly based on clinical series and case reports. CTPV often manifests as gastroesophageal variceal bleeding, splenomegaly, and portal biliopathy after the long-term insidious presentation. It is unable for CTPV to be recanalized with anticoagulation because it is a complete obstruction of the mesentericoportal axis. Endoscopic therapy is mainly used for temporary hemostasis in acute variceal bleeding. Meso-Rex shunting characterized by portal-flow-preserving shunts has been widely performed in children with CTPV. The multitude of complications associated with CTPV in adults can be effectively addressed by various interventional vascular therapies. With the ubiquity of radiological examinations, optimal treatment for patients with CTPV becomes important. Multivisceral transplantation, such as liver-small intestinal transplantation, may be lifesaving and should be considered for patients with diffuse mesenteric venous thrombosis.

Pediatric non-cirrhotic portal hypertension: Endoscopic outcome and perspectives from developing nations

Non-cirrhotic portal hypertension (NCPH) forms an important subset of portal hypertension in children. Variceal bleed and splenomegaly are their predominant presentation. Laboratory features show cytopenias (hypersplenism) and preserved hepatic synthetic functions. Repeated sessions of endoscopic variceal ligation or endoscopic sclerotherapy eradicate esophageal varices in almost all cases. After variceal eradication, there is an increased risk of other complications like secondary gastric varices, cholangiopathy, colopathy, growth failure, especially in extra-hepatic portal vein obstruction (EHPVO). Massive splenomegaly-related pain and early satiety cause poor quality of life (QoL). Meso-Rex bypass is the definitive therapy when the procedure is anatomically feasible in EHPVO. Other portosystemic shunt surgeries with splenectomy are indicated when patients present late and spleen-related issues predominate. Shunt surgeries prevent rebleed, improve growth and QoL. Non-cirrhotic portal fibrosis (NCPF) is a less common cause of portal hypertension in children in developing nations. Presentation in the second decade, massive splenomegaly and patent portal vein are discriminating features of NCPF. Shunt surgery is required in severe cases when endotherapy is insufficient for the varices. Congenital hepatic fibrosis (CHF) presents with firm palpable liver and splenomegaly. Ductal plate malformation forms the histological hallmark of CHF. CHF is commonly associated with Caroli’s disease, renal cysts, and syndromes associated with neurological defects. Isolated CHF has a favourable prognosis requiring endotherapy. Liver transplantation is required when there is decompensation or recurrent cholangitis, especially in Caroli’s syndrome. Combined liver-kidney transplantation is indicated when both liver and renal issues are present.

Diagnosis and management of extrahepatic oesophageal variceal bleed in children in a low resourced setting

Extrahepatic portal vein obstruction (EHPVO) is a major cause of portal hypertension (PH) in children. Portal vein thrombosis (PVT) is the most common cause accounting for up to 75% of cases in developing countries. Upper gastrointestinal bleeding is the most dreaded and commonest presentation of portal hypertension. Successful treatment of paediatric PH, though challenging is performed in resource constraint countries.

Jejunal varices with extra hepatic portal vein obstruction: A case report

Introduction and importance

Extrahepatic portal vein obstruction (EHPVO) with portal hypertension is rare in children. Intestinal varices as new collaterals accompanying portal hypertension are very rare.

Presentation of case

We report an unusual case of a 12-year-old boy with EHPVO with gastrointestinal bleeding from ectopic jejunal varices, without any gastroesophageal varices.

Discussion

Portal hypertension is the most common cause of EHPVO. Among various ectopic varices, intestinal varices are found distal to the duodenum and present with complaints of hematochezia, melena, or intraperitoneal bleeding. The diagnosis of the EHPVO is aided by imaging investigations like Doppler ultrasound, computed tomography, or magnetic resonance imaging. A multidisciplinary team including gastroenterologists, interventional radiologists, surgeons, and intensivists is crucial in the management of ectopic varices.

Conclusion

Jejunal varices must be considered in the differential diagnosis of gastrointestinal (GI) hemorrhage in patients with a negative source of bleed on upper and lower GI endoscopy.

•

Intestinal varices are rarely developed as new collaterals accompanying portal hypertension with EHPVO (Extrahepatic portal vein obstruction).

•

Jejunal varices must be considered in patients with a negative source of bleed on upper and lower GI endoscopy.

Therapeutic Upper Gastrointestinal Endoscopy in Pediatric Gastroenterology

This paper seeks to give a broad overview of pediatric upper gastrointestinal (GI) pathologies that we are now able to treat endoscopically, acquired or congenital, and we hope this delivers the reader an impression of what is increasingly available to pediatric endoscopists and their patients.

Ascites in children with extrahepatic portal venous obstruction: Etiology, risk factors and outcome

BACKGROUND

Ascites in extrahepatic portal venous obstruction (EHPVO)  is uncommon. We studied the etiology and natural history of ascites and risk factors of post-bleeding ascites in children with EHPVO.

METHODS

All admitted EHPVO patients with clinically detectable ascites and/or gastrointestinal (GI) bleeding in previous 6 weeks were analysed. Subjects with ascites were classified as post-bleeding ascites and de-novo ascites (no GI bleeding) Post-bleeding ascites group was compared with controls (GI bleeding without ascites) for risk factors of developing ascites.

RESULTS

Of the total 307 analysed EHPVO patients, 26% (n=79) had ascites. Majority (n=66, 83%) were post-bleeding ascites and 17% (n=13) had de-novo ascites due to secondary causes. Risk factors of ascites in post-bleeding ascites (n=56) versus controls (n=188) were younger age of disease onset, lower height z-scores and greater reduction in serum protein, albumin and hemoglobin from baseline non-bled state. 32%, 39%, and 29% of patients with post-bleeding ascites had ascites resolution with salt restriction, additional diuretics and large volume paracentesis respectively.

CONCLUSIONS

Majority of ascites in EHPVO children is after GI bleeding where early age of disease onset, large volume of blood loss and poor nutritional status are risk factors. Overall outcome of EHPVO with ascites is favourable.

Endoscopic prophylaxis and factors associated with bleeding in children with extrahepatic portal vein obstruction

OBJECTIVES

This study aimed to evaluate factors associated with upper digestive hemorrhage and primary and secondary endoscopic prophylaxis outcomes in children with extrahepatic portal vein obstruction.

METHODS

This observational and prospective study included 72 children with extrahepatic portal vein obstruction who were followed from 2005 to 2017. Risk factors associated with upper digestive hemorrhage and the results of primary and secondary prophylaxis of these patients were evaluated.

RESULTS

Fifty patients (69.4%) had one or more episodes of bleeding during follow-up, with a median age at first hemorrhage of 4.81 years. The multivariate analysis showed that medium- to large-caliber esophageal varices were associated with an 18-fold risk of upper digestive hemorrhage (95% CI: 4.33-74.76; p < 0.0001). Primary prophylaxis was administered to 14 patients, with eradication in 85.7%; however, 14.3% of these patients had hemorrhages during the follow-up period and 41.7% had a relapse of varices. Secondary prophylaxis was administered to 41 patients. Esophageal varices were eradicated in 90.2% of patients. There were relapse and re-bleeding of esophageal varices in 45.9% and 34.1% of the children, respectively.

CONCLUSION

Primary and secondary endoscopic prophylaxes showed high rates of esophageal varix eradication, but with significant relapses. Eradication of esophageal varices cannot definitively prevent recurrent upper digestive hemorrhage, since bleeding from alternate sites can occur. Medium- and large-caliber esophageal varices were associated with upper digestive hemorrhage in patients with extrahepatic portal vein obstruction. To the best of the authors' knowledge, this study is the first to evaluate bleeding risk factors in children with extrahepatic portal vein obstruction.

Pharmacological management of portal hypertension and its complications in children: lessons from adults and opportunities for the future

INTRODUCTION

Portal hypertension (PHT) and its complications in children are thought to be distinct from adult PHT in several areas, including the underlying bio-physiology of a child in which PHT develops, but also because of the pediatric-specific etiologies that drive disease progression. And yet pharmacologic approaches to PHT in children are mainly based on adult data, modified for pediatric practice. This reality has been driven by a lack of data specific to children.

AREAS COVERED

The authors discuss current therapeutic approaches to PHT in children, including management of acute gastrointestinal variceal bleed, pharmacotherapy in prophylaxis, and established and emerging therapies to combat systemic co-morbidities that result from PHT. The few areas where pediatric-specific data exist are highlighted and the many gaps in knowledge that remain unresolved are underscored.

EXPERT OPINION

Despite decades of experience, optimal management of pediatric PHT remains undefined. In large part, this can be directly linked to a lack of basic understanding related to the unique pathophysiology and natural history that defines PHT in children. As a result, meaningful research into the utility and effectiveness of pharmacotherapy in children with PHT remains in its infancy. Large, multi-center, prospective studies will be needed to begin to establish an infrastructure on which a pediatric-specific research agenda can be built.

Portal cavernoma or chronic non cirrhotic extrahepatic portal vein obstruction

Chronic non cirrhotic extrahepatic portal vein obstruction (EHPVO) refers to the cavernomatous transformation of the portal vein (the so-called "portal cavernoma") which occurs following acute thrombosis of the portal vein in the absence of recanalization. In adults, EHPVO mainly occurs following thrombosis, while in children it may be related to congenital malformations and/or neonatal umbilical venous catheterization. However, 50% of the cases of EHPVO remain idiopathic [1]. Risk factors and associated diseases should be investigated (chapter 1). Indeed, the presence of a thrombophilic alteration, in particular myeloproliferative neoplasm impacts prognosis and determine a causal treatment.

Noncirrhotic Portal Hypertension: Current and Emerging Perspectives

Idiopathic portal hypertension (IPH) and extrahepatic portal venous obstruction (EHPVO) are prototype noncirrhotic causes of portal hypertension (PHT), characterized by normal hepatic venous pressure gradient, variceal bleeds, and moderate to massive splenomegaly with preserved liver synthetic functions. Infections, toxins, and immunologic, prothrombotic and genetic disorders are possible causes in IPH, whereas prothrombotic and local factors around the portal vein lead to EHPVO. Growth failure, portal biliopathy, and minimal hepatic encephalopathy are long-term concerns in EHPVO. Surgical shunts and transjugular intrahepatic portosystemic shunt resolve the complications secondary to PHT. Meso-Rex shunt is now the standard-of-care surgery in children with EHPVO.

Etiology, presenting features and outcome of children with non-cirrhotic portal vein thrombosis: A multicentre national study

OBJECTIVES

Non-cirrhotic portal vein thrombosis (PVT) is a main cause of portal hypertension in children. We describe the characteristics at presentation and outcome of a cohort of patients with PVT to determine clinical features and predictors of outcome.

METHODS

We recorded: (1) Associated factors: prematurity, congenital malformations, neonatal illnesses, umbilical vein catheterization (UVC), deep infections, surgery; (2) congenital and acquired prothrombotic disorders; (3) features at last follow up including survival rate and need for surgery.

RESULTS

187 patients, mean age at diagnosis 4 ± 3.7 years, had a history of prematurity (61%); UVC (65%); neonatal illnesses (79%). The diagnosis followed the detection of splenomegaly (40%), gastrointestinal bleeding (36%), hypersplenism (6%), or was incidental (18%). Of 71 patients who had endoscopy at presentation 62 (87%) had oesophageal varices. After 11.3 years' follow up 63 (34%) required surgery or TIPS. Ten-year survival rate was 98%, with 90% shunt patency. Spleen size, variceal bleeding and hypersplenism at presentation were predictors of surgery or TIPS (p < 0.05).

CONCLUSION

PVT is associated with congenital and acquired co-morbidities. History of prematurity, neonatal illnesses and UVC should lead to rule out PVT. Large spleen, variceal bleeding and hypersplenism at presentation predict the need for eventual surgery in a third of cases.

Portal Cavernoma Cholangiopathy: Histologic Features and Differential Diagnosis

Objectives

Portal cavernoma cholangiopathy (formerly portal biliopathy) is a type of biliary injury that occurs in association with a portal vein thrombus or cavernoma. Although the radiographic features of portal cavernoma cholangiopathy have been enumerated in the literature, its histologic features have not been described in detail.

Methods

We describe the histologic findings in liver specimens from three patients with radiologically confirmed portal cavernoma cholangiopathy.

Results

Of the three patients, one underwent surgical resection due to a clinical suspicion for cholangiocarcinoma, one had a liver biopsy sample obtained for evaluation of possible cirrhosis, and one had a clinically suspicious "hilar mass" at the time of orthotopic liver transplant. Histologic features common among the three liver specimens included portal venous abnormalities, where the portal veins were obliterated or small relative to the portal tract size, and obstructive biliary changes, such as ductular reaction and reactive epithelial atypia accompanied by a mixed inflammatory cell infiltrate with neutrophils.

Conclusions

This case series provides clinicopathologic characteristics of portal cavernoma cholangiopathy. Histologic changes are reminiscent of hepatoportal sclerosis and/or bile duct obstruction. Attention to portal veins can provide helpful diagnostic clues, especially when biopsy samples are obtained from patients with a known portal vein thrombus or cavernoma.

Cirrhosis and Portal Hypertension in the Pediatric Population

Cirrhosis is a complex process in which the architecture of the liver is replaced by structurally abnormal nodules due to cirrhosis. Cirrhosis frequently leads to the development of portal hypertension. In children, portal hypertension may be caused by a wide range of etiologies, including extrahepatic portal vein obstruction, biliary atresia, alpha 1 antitrypsin deficiency, and autoimmune hepatitis. Gastroesophageal varices and ascites are two of the complications of portal hypertension likely to cause morbidity and mortality. This review also discusses extrahepatic manifestations of portal hypertension and treatment options.

Idiopathic portal hypertension and extrahepatic portal venous obstruction

BACKGROUND

Idiopathic portal hypertension (IPH) and extrahepatic portal venous obstruction (EHPVO) are non-cirrhotic vascular causes of portal hypertension (PHT). Variceal bleed and splenomegaly are the commonest presentations.

AIM

The present review is intended to provide the existing literature on etiopathogenesis, clinical profile, diagnosis, natural history and management of IPH and EHPVO.

RESULTS

IPH and EHPVO are both characterized by normal hepatic venous pressure gradient, moderate to massive splenomegaly with preserved liver synthetic functions. While the level of block in IPH is presinusoidal, in EHPVO it is at prehepatic level. Infections, autoimmunity, drugs, immunodeficiency and prothrombotic states are possible etiological agents in IPH. Contrastingly in EHPVO, prothrombotic disorders and local factors around the portal vein are the incriminating factors. Diagnosis is often clinical, supported by simple radiological tools. Natural history is defined by episodes of variceal bleed and symptoms related to enlarged spleen. Growth failure, portal biliopathy and minimal hepatic encephalopathy are additional concerns in EHPVO. Long-term survival is reasonably good with endoscopic surveillance; however, parenchymal extinction leading to decompensation is seen in a minority of patients in both the disorders. Surgical shunts revert the complications secondary to PHT. Meso-Rex shunt has become the standard surgery in children with EHPVO.

CONCLUSION

This review gives a detailed summary of these two vascular conditions of liver-IPH and EHPVO. Further research is needed to understand the pathogenesis and natural history of these disorders.

Portal hypertension and its management in children

Portal hypertension (PHT), defined as raised intravascular pressure in the portal system, is a complication of chronic liver disease or liver vascular occlusion. Advances in our ability to diagnose and monitor the condition but also predict the risk of gastrointestinal bleeding have enabled us to optimise the management of children with PHT either at a surveillance or at a postbleeding stage. A consensus among paediatric centres in the classification of varices can be beneficial in streamlining future paediatric studies. New invasive (endoscopic and surgical procedures) and non-invasive (pharmacotherapy) techniques are currently used enabling clinicians to reduce mortality and morbidity in children with PHT.

Combined Rex-bypass shunt with pericardial devascularization alleviated prehepatic portal hypertension caused by cavernomatous transformation of portal vein

OBJECTIVE

To evaluate the effects of combined Rex-bypass shunt and pericardial devascularization on prehepatic portal hypertension secondary to cavernomatous transformation of portal vein (CTPV).

METHODS

Forty-two patients aged from 3 years to 49 years (divided into 3 groups), 26 cases male and 16 female, with prehepatic vascular hepertention were treated with Rex-bypass shunt combined with pericardial devascularization. In each patient, preoperative assessment included ultrasound and computed tomographic angiography of the portal vein and blood analysis. The procedure was Rex-bypass shunt (with or without graft), and patients with moderate or severe gastroesophageal varices required additional paraesophagogastric devascularization. Splenectomy or subtotal splenectomy was performed if combined hypersplenism co-existed. All data were analyzed retrospectively.

RESULTS

No intraoperative death occurred, blood routine analysis improved (P < 0.05), the blood flow velocity (P < 0.05) and diameter (P < 0.05) of the left portal vein (LPV) significantly increased, the esophageal and gastric varices significantly relieved in 34 patients (P < 0.05), and better effects of earlier operations were demonstrated than the delayed ones (P < 0.05). During the period of follow-up from 6 to 64 months, the overall patency rate was 85.7% and the younger the age the better of the effect.

CONCLUSION

Rex-bypass shunt combined with pericardial devascularization is a safe and effective procedure for prehepatic portal hypertension caused by CTPV.

Working Subgroup for Clinical Practice Guideline for Aberrant Portal Hemodynamics. Diagnosis and treatment guidelines for aberrant portal hemodynamics: The Aberrant Portal Hemodynamics Study Group supported by the Ministry of Health, Labor and Welfare of Japan

Idiopathic portal hypertension (IPH), causing aberrant portal hemodynamics, is a disease with an as yet unidentified cause and no established treatment protocol. The Japanese research group on IPH in Japan was set up in 1975 by the Ministry of Health, Labor and Welfare. Extrahepatic portal obstruction and Budd-Chiari syndrome (BCS) have since been added to the group's research subjects. The aims of the research group are to accurately evaluate the current status of the three diseases in Japan, elucidate their etiology and pathogenesis, and develop new treatments. Due to the long-term efforts of the Japanese research group, aberrant portal hemodynamics has been investigated in a variety of aspects, from epidemiological and pathological studies to molecular biology analyses. As a result, it has been shown that there are abnormal genes in the liver, specific for IPH. In addition, pathological findings of BCS were internationally compared and the difference in findings between Japan and Europe (or North America) has been clarified. Furthermore, it was found that complication rates of hepatocellular carcinoma in BCS were higher in Japan. Based on the research, "Diagnosis and treatment of aberrant portal hemodynamics (2001)", including diagnostic criteria for aberrant portal hemodynamics, was published in 2001. In 2013, it was revised to "Diagnosis and treatment guidelines for aberrant portal hemodynamics (2013)" after the incorporation of diagnosis and treatment in accordance with its current status.

A pilot study using lactulose in management of minimal hepatic encephalopathy in children with extrahepatic portal vein obstruction

BACKGROUND

Minimal hepatic encephalopathy (MHE) is not associated with overt neuropsychiatric symptoms but rather with subtle changes in psychometric and/or neurophysiologic tests. We aimed to diagnose MHE in children with extrahepatic portal vein obstruction (EHPVO) and to evaluate the effect of lactulose on MHE.

METHODS

A prospective study was carried out on 30 patients with EHPVO (21 males; mean age 10±2.5 years). The study was carried out in the Pediatric Hepatology Unit, Cairo University Pediatric Hospital, Cairo, Egypt, between 2011 and 2013. All patients were subjected to clinical and laboratory assessment, neuropsychmetric testing using the arabic version of Wechsler intelligence tests, neurophysiological testing by visual electroencephalogram and P300 event related potentials (ERP).

RESULTS

The prevalence of MHE among children with EHPVO was 20% (6/30). After randomization to treatment and no-treatment groups using lactulose, all tests were repeated after three months. Among four patients with MHE who received lactulose, three (75%) improved. On the other hand, one of the patients in the no-treatment group developed MHE. Only one patient in the treatment arm had to discontinue lactulose because of severe diarrhea.

CONCLUSIONS

This pilot study revealed that the prevalence of MHE was 20%. Improvement on psychometic tests was seen in 75% of our patients (3/4) after treatment with lactulose. Lactulose treatment was well tolerated.

Low frequency of V617F mutation in JAK2 gene in Indian patients with hepatic venous outflow obstruction and extrahepatic portal venous obstruction

BACKGROUND

Hepatic venous outflow tract obstruction (HVOTO) and extrahepatic portal venous obstruction (EHPVO) are important causes of portal hypertension and related complications in India. Both these conditions result from splanchnic venous thrombosis. In recent years, a V617F somatic mutation in Janus kinase 2 (JAK2) gene which is highly specific for myeloproliferative disorders has been detected in 40 % to 50 % and 30 % to 35 % of Western patients with HVOTO and EHPVO, respectively. However, data on this mutation in these conditions from Asian countries are limited.

METHODS

We looked for JAK2 V617F mutation in Indian patients with HVOTO (n = 40, median age 31 [range 17-51] years, 21 female) and EHPVO (n = 50, median age 23 [15-70] years, 25 female) by using two separate methods. Both the methods involved polymerase chain reaction using allele-specific primers. Positive results on one or both of these techniques were confirmed using DNA sequencing.

RESULTS

None of the 40 patients with HVOTO and only 1 of 50 patients with EHPVO was found to have JAK2 V617F mutation. In the one patient who was found to have this mutation, both the PCR methods and DNA sequencing showed positive results.

CONCLUSION

Hypercoagulability associated with JAK2 V617F mutation and associated chronic myeloproliferative disorders was not a major cause of HVOTO and EHPVO in this population.

Primary prophylaxis of variceal bleeding in children and the role of MesoRex Bypass: Summary of the Baveno VI Pediatric Satellite Symposium

Approaches to the management of portal hypertension and variceal hemorrhage in pediatrics remain controversial, in large part because they are not well informed by rigorous clinical studies. Fundamental biological and clinical differences preclude automatic application of approaches used for adults to children. On April 11-12, 2015, experts in the field convened at the first Baveno Pediatric Satellite Meeting to discuss and explore current available evidence regarding indications for MesoRex bypass (MRB) in extrahepatic portal vein obstruction and the role of primary prophylaxis of variceal hemorrhage in children. Consensus was reached regarding MRB. The vast majority of children with extrahepatic portal vein obstruction will experience complications that can be prevented by successful MRB surgery. Therefore, children with extrahepatic portal vein obstruction should be offered MRB for primary and secondary prophylaxis of variceal bleeding and other complications, if appropriate surgical expertise is available, if preoperative and intraoperative evaluation demonstrates favorable anatomy, and if appropriate multidisciplinary care is available for postoperative evaluation and management of shunt thrombosis or stenosis. In contrast, consensus was not achieved regarding primary prophylaxis of varices. Although variceal hemorrhage is a concerning complication of portal hypertension in children, the first bleed appears to be only rarely fatal and the associated morbidity has not been well characterized.

CONCLUSION

There are few pediatric data to indicate the efficacy and safety of pharmacologic or endoscopic therapies as primary prophylaxis or that prevention of a sentinel variceal bleed will ultimately improve survival; therefore, no recommendation for primary prophylaxis with endoscopic variceal ligation, sclerotherapy, or nonspecific beta-blockade in children was proposed.

Extrahepatic portal vein obstruction in Egyptian children

BACKGROUND AND AIM

Extrahepatic portal vein obstruction (EHPVO) is an important cause of portal hypertension in children. The aim of this study was to describe the clinical presentation, possible risk factors, upper gastrointestinal endoscopic findings, and treatment modalities of children with EHPVO.

METHODS

After ethical approval of our study protocol by our institution review board, we analyzed available data from medical records of patients with EHPVO presenting to the Pediatric Hepatology Unit, Cairo University Pediatric Hospital, Egypt, for a period of 15 years from January 1996 to December 2010.

RESULTS

The study included 169 patients. Their ages at presentation ranged from 1 month to 12 years (median 2.5 years, interquartile range 5); 101 were boys. Hematemesis was a presenting symptom in 58%, splenomegaly was present in 87%, esophageal varices were present in 94%, and fundal varices were present in 23%. Possible risk factors, in the form of umbilical catheterization, umbilical sepsis, and exchange transfusion, were elicited in 18%. Propranolol was associated with reduction in bleeding episodes (P < 0.001), but was associated with increased chest symptoms (P < 0.01). Both injection sclerotherapy and band ligation were effective in the management of bleeding varices and for primary and secondary prophylaxis; however, injection sclerotherapy was associated with the development of secondary gastric varices (P = 0.03).

CONCLUSIONS

This large study of children with EHPVO demonstrates the efficacy of propranolol in the reduction of gastrointestinal bleeding in children with EHPVO. Both injection sclerotherapy and band ligation were effective in the management of esophageal varices, although the former was associated with the development of secondary gastric varices. Randomized clinical trials to choose the best modalities for the management of portal hypertension in children are still lacking.

Non-cirrhotic portal hypertension

Non-cirrhotic portal hypertension (NCPH) encompasses a wide range of disorders, primarily vascular in origin, presenting with portal hypertension (PHT), but with preserved liver synthetic functions and near normal hepatic venous pressure gradient (HVPG). Non-cirrhotic portal fibrosis/Idiopathic PHT (NCPF/IPH) and extrahepatic portal venous obstruction (EHPVO) are two prototype disorders in the category. Etiopathogenesis in both of them centers on infections and prothrombotic states. Presentation and management strategies focus on repeated well tolerated episodes of variceal bleed and moderate to massive splenomegaly and other features of PHT. While the long-term prognosis is generally good in NCPF, portal biliopathy and parenchymal extinction after prolonged PHT makes outcome somewhat less favorable in EHPVO. While hepatic schistosomiasis, congenital hepatic fibrosis and nodular regenerative hyperplasia have their distinctive features, they often present with NCPH.

Revisiting extra hepatic portal vein obstruction in children from the north Indian gangetic plain

OBJECTIVES

To study the demographic features, etiology, clinical, radiology and laboratory findings in children with Extra hepatic portal vein obstruction (EHPVO) from the North Indian Gangetic Plain.

METHODS

A prospective analysis of 53 patients of EHPVO (<14 y of age) was done. Data for clinical presentation, laboratory workup, endoscopic procedures, growth and development, management and outcome were analyzed.

RESULTS

A total of 53 patients (32 male, 21 female) with mean age of 8.66 ± 3.32 y at presentation were included. Growth retardation was present in 30 (56.60 %) patients at time of diagnosis. The most common presenting symptoms were upper gastrointestinal bleeding (86.80 %) and an incidental finding of splenomegaly (13.2 %). Hematological parameters of hypersplenism were present in 9 (17 %) patients. Protein C (PC), Protein S (PS), antithrombin III (AT) deficiency were found in 8 (20 %), 4 (10 %) and 6 (15 %) of the patients respectively in 40 patients tested. On first endoscopy, esophageal varices were present in all patients. Endoscopic sclerotherapy (EST)/band ligation (EBL) was performed in 46 bleeder patients and success rate was 83.3 % for sclerotherapy and 90 % for band ligation.

CONCLUSIONS

The etiology of EHPVO in the majority of patients remains elusive. It results in impaired somatic growth. Sclerotherapy and endoscopic banding are effective means for treatment for bleeding varices. It is still not clear whether deficiency of anticoagulant proteins is a primary event or secondary to disease process.

Non-cirrhotic portal hypertension - diagnosis and management

NCPH is a heterogeneous group of liver disorders of vascular origin, leading to PHT with near normal HVPG. NCPF/IPH is a disorder of young adults or middle aged women, whereas EHPVO is a disorder of childhood. Early age acute or recurrent infections in an individual with thrombotic predisposition constitute the likely pathogenesis. Both disorders present with clinically significant PHT with preserved liver functions. Diagnosis is easy and can often be made clinically with support from imaging modalities. Management centers on control and prophylaxis of variceal bleeding. In EHPVO, there are additional concerns of growth faltering, portal biliopathy, MHE and parenchymal dysfunction. Surgical shunts are indicated in patients with failure of endotherapy, bleeding from sites not amenable to endotherapy, symptomatic hypersplenism or symptomatic biliopathy. Persistent growth failure, symptomatic and recurrent hepatic encephalopathy, impaired quality of life or massive splenomegaly that interferes with daily activities are other surgical indications. Rex-shunt or MLPVB is the recommended shunt for EHPVO, but needs proper pre-operative radiological assessment and surgical expertise. Both disorders have otherwise a fairly good prognosis, but need regular and careful surveillance. Hepatic schistosomiasis, CHF and NRH have similar presentation and comparable prognosis.

Ultrasonographic predictors of esophageal varices

OBJECTIVE

The aim of this study was to identify ultrasonographic predictors of esophageal varices (EVs) in children and adolescents with chronic liver disease (CLD) and extrahepatic portal venous obstruction (EHPVO).

METHODS

This study evaluates 53 patients younger than 20 years with CLD or EHPVO and no history of bleeding or prophylactic EVs treatment. They were divided into 2 groups: group I (35 with CLD) and group II (18 with EHPVO). Splenorenal shunt (SS), gallbladder wall varices, gallbladder wall thickening (GT), and lesser omental thickness (LOT) were compared with the presence of EVs, gastric varices, and portal hypertensive gastropathy (PHG). Univariate (χ² test, Fisher exact test, and Wilcoxon signed rank test) and multivariate (logistic regression) analyses were performed. The area under the receiver operating curve was calculated.

RESULTS

EVs were observed in 48.5% of patients with CLD and in 83.3% of patients with EHPVO. SS (P = 0.0329) and LOT (P = 0.0151) predicted EV among patients with CLD. A median of 5.3 mm of LOT was considered a predictor of EVs among these patients. Multivariate analysis showed SS as an independent predictor of EVs in patients with EHPVO (odds ratio 15). Gallbladder varices (P = 0.0245) and GT (P = 0.0289) predicted EVs among patients with EHPVO. PHG occurred more often among patients with CLD who had SS (P = 0.0384) and greater LOT (P = 0.0226).

CONCLUSIONS

SS and a greater LOT were indicative of EV among children and adolescents with CLD. Gallbladder varices and GT were indicative of EVs among patients with EHPVO. SS and a greater LOT were indicative of PHG among patients with CLD.

Meso-Rex bypass for extrahepatic portal vein obstruction in children

Background

Meso-Rex bypass (MRB) and portosystemic surgical shunt (PSS) are both used to treat extrahepatic portal vein obstruction (EHPVO) in children. The aim of this study was to analyse the outcome of MRB and PSS to select patients who could benefit from a prophylactic MRB.

Methods

This single-centre retrospective study of children who underwent either MRB or PSS for EHPVO was conducted between 1996 and 2010. Details of patient demographics and preoperative evaluation were collected. Success rates, defined as shunt patency after a minimum of 6 months and clearance of varices or symptoms, were compared. Determinants of outcomes were explored.

Results

Sixty-nine patients underwent a MRB or PSS. Median (interquartile range, i.q.r.) age at surgery was 6·6 (4·0–10·6) years. Twenty-four patients (35 per cent) had had a neonatal umbilical catheter (NUC) placed previously and 47 (68 per cent) had experienced an upper gastrointestinal bleed. Imaging assessment of the intrahepatic left portal vein was considered favourable in 40 patients. Of 43 MRBs attempted, 11 failed during surgery and four patients had persistent thrombosis after a median of 55 (i.q.r. 18–107) months. The success rate of MRB was 60 per cent (26 of 43) compared with 100 per cent (26 of 26) for PSS (P &lt; 0·001). It was lower among patients in whom a NUC had been used (2 of 10 versus 24 of 33; P = 0·004), for procedures undertaken early in the series (6 of 16 versus 20 of 27; P = 0·020) and when the imaging pattern was unfavourable (0 of 5 versus 26 of 38; P = 0·006). On multivariable analysis, only a previous history of NUC predicted failure (P = 0·016).

Conclusion

Prophylactic MRB seems a good treatment option for EHPVO in children, but should be done only by an experienced team in patients with favourable imaging and without a previous history of NUC.

Presented in part to the 43rd Annual Meeting of the American Pediatric Surgical Association, San Antonio, Texas, USA, May 2012

Management of portal hypertension in children with portal vein thrombosis

Portal vein thrombosis (PVT) is a common cause of portal hypertension in children. Predisposing conditions for PVT are obscure in more than half of the cases. Variceal bleeding and splenomegaly are the most frequent initial manifestations. Radiologic imaging studies are the mainstay for diagnosis. Treatment includes pharmacologic, endoscopic, and surgical modalities. β-Adrenergic blockers are not routinely used in children because of unproven efficacy and significant adverse effects. Endoscopic methods, such as sclerotherapy and endoscopic variceal ligation (EVL), are highly effective in the treatment of acute variceal bleeding and eradication of varices. EVL is the treatment of choice because of minimal complications and the need for few endoscopic sessions. EVL facilitates portal decompression either by the formation of collateral vessels or by surgical portosystemic shunting, when vessels grow to the proper diameter for anastomosis. Surgical portosystemic shunts are reserved for refractory cases because of significant complications and technical difficulties. Transjugular portosystemic shunts have an emerging role in the management of portal hypertension caused by PVT. PVT may occur in the posttransplant setting, but optimal management is not defined yet.

Guidelines for the diagnosis and treatment of extrahepatic portal vein obstruction (EHPVO) in children

INTRODUCTION

Extrahepatic portal vein obstruction is an important cause of portal hypertension among children. The etiology is heterogeneous and there are few evidences related to the optimal treatment.

AIM AND METHODS

To establish guidelines for the diagnosis and treatment of EHPVO in children, a group of gastroenterologists and pediatric surgery experts reviewed and analyzed data reported in the literature and issued evidence-based recommendations.

RESULTS

Pediatric EHPVO is idiopathic in most of the cases. Digestive hemorrhage and/or hypersplenism are the main symptoms. Doppler ultrasound is a non-invasive technique with a high degree of accuracy for the diagnosis. Morbidity is related to variceal bleeding, recurrent thrombosis, portal biliopathy and hypersplenism. Endoscopic therapy is effective in controlling acute variceal hemorrhage and it seems that vasoactive drug therapy can be helpful. For primary prophylaxis of variceal bleeding, there are insufficient data for the use of beta blockers or endoscopic therapy. For secondary prophylaxis, sclerotherapy or variceal band ligation is effective; there is scare evidence to recommend beta-blockers. Surgery shunt is indicated in children with variceal bleeding who fail endoscopic therapy and for symptomatic hypersplenism; spleno-renal or meso-ilio-cava shunting is the alternative when Mesorex bypass is not feasible due to anatomic problems or in centers with no experience.

CONCLUSIONS

Prospective control studies are required for a better knowledge of the natural history of EHPVO, etiology identification including prothrombotic states, efficacy of beta-blockers and comparison with endoscopic therapy on primary and secondary prophylaxis.

Evaluation of the presence of hereditary and acquired thrombophilias in Brazilian children and adolescents with diagnoses of portal vein thrombosis

OBJECTIVE

The aim of this study was to describe the prevalence of main hereditary thrombophilias, Janus kinase 2 (JAK2) V617F mutation, antiphospholipid antibody syndrome (APS), and hyperhomocysteinemia in Brazilian children and adolescents diagnosed with portal vein thrombosis (PVT) without associated hepatic disease.

METHODS

A cross-sectional study was carried out with 32 children with PVT in accompaniment at Hospital das Clínicas of the Universidade Federal de Minas Gerais from January 1990 to July 2011. Laboratory evaluation of thrombophilias was performed from September 2010 to July 2011.

RESULTS

Thirty-two patients were evaluated; 59% were boys. Median age at diagnosis was 2.4 years. Mean time of patients' accompaniment was between 4.7 and 5.2 years. The presence of hereditary and acquired thrombophilias occurred in 34.4% of patients, and 9 of them also showed other risk factors in the previous history evaluation. Risk factors were absent in the previous history of 18 patients (56.3%). Two patients showed persistent high titres of anticardiolipin antibodies. Hyperhomocysteinemia was not observed. One patient was heterozygous for factor V Leiden and prothrombin G20210A mutation (3.1%). Eleven patients (34.4%) showed heterozygous methylenetetrahydrofolate reductase (MTHFR) C677T, and no patient had the JAK2V617F mutation.

CONCLUSIONS

Even after investigation of main hereditary and acquired thrombophilia, PVT remains without apparent cause in most patients. Nevertheless, association of local and systemic risk factors seems to be important also in the pediatric age group. Therefore, despite the low prevalence, a complete investigation, which includes both hereditary and acquired thrombophilias, may be necessary.

Portal vein thrombosis in children and adolescents: 20 years experience of a pediatric hepatology reference center

CONTEXT

Portal vein thrombosis refers to a total or partial obstruction of the blood flow in this vein due to a thrombus formation. It is an important cause of portal hypertension in the pediatric age group with high morbidity rates due to its main complication - the upper gastrointestinal bleeding.

OBJECTIVE

To describe a group of patients with portal vein thrombosis without associated hepatic disease of the Pediatric Hepatology Clinic of the Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil with emphasis on diagnosis, presentation form and clinical complications, and the treatment of portal hypertension.

METHODS

This is a descriptive study of a series of children and adolescents cases assisted from January 1990 to December 2010. The portal vein thrombosis diagnosis was established by ultrasound.

RESULTS

Of the 55 studied patients, 30 (54.5%) were male. In 29 patients (52.7%), none of the risk factors for portal vein thrombosis was observed. The predominant form of presentation was the upper gastrointestinal bleeding (52.7%). In 20 patients (36.4%), the initial manifestation was splenomegaly. During the whole following period of the study, 39 patients (70.9%) showed at least one episode of upper gastrointestinal bleeding. The mean age of patients in the first episode was 4.6 ± 3.4 years old. The endoscopic procedure carried out in the urgency or electively for search of esophageal varices showed its presence in 84.9% of the evaluated patients. The prophylactic endoscopic treatment was performed with endoscopic band ligation of varices in 31.3% of patients. Only one died due to refractory bleeding.

CONCLUSIONS

The portal vein thrombosis is one of the most important causes of upper gastrointestinal bleeding in children. In all non febrile children with splenomegaly and/or hematemesis and without hepatomegaly and with normal hepatic function tests, it should be suspect of portal vein thrombosis. Thus, an appropriate diagnostic and treatment approach is desirable in an attempt to reduce morbidity and mortality.

Medical management of esophageal varices and portal hypertension in children

Portal hypertension (PH) is a common complication of chronic liver disease in children and represents a cause of morbidity and, rarely, mortality in this group of patients. Although often self-limiting, gastrointestinal bleeding in this setting is regarded as a frightening event by patients and carers, giving the impression of impending death. Therefore, it is important to raise the awareness on the natural history of PH in children, the utility of tools that help preventing and managing acute bleeding, and the signs predicting a poor outcome, thus indicating surgery. There is lack of data on the ability of endoscopy screening, endoscopic treatment of varices, and use of nonselective β-blockers to alter the outcome of PH in children; major efforts should be made to avoid such treatments empirically and promote multicenter trials instead. Nevertheless, such approach should be balanced against the need of offering the best care to children with PH. In this review, we discuss the advances made in the management of PH in children and compare it with the larger adult experience. A rational approach to acute gastrointestinal bleeding is proposed along with an algorithm suggesting a stepwise protocol to manage children with esophageal varices in the long-term, with some hints on possible future studies.

Pre- and postoperative imaging of the Rex shunt in children: what radiologists should know

OBJECTIVE

The objective of this article is to illustrate the imaging features of patients with extrahepatic portal venous obstruction who are evaluated before or after a Rex shunt surgery.

CONCLUSION

The Rex shunt is a potentially curative surgical procedure that reestablishes physiologic hepatopetal portal flow. It is typically accomplished by interposing a vascular conduit between the superior mesenteric vein to the still patent intrahepatic portal venous system. This procedure results in resolution of portal hypertension.