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

Portal Hypertension in Children: Investigating Umbilical Catheterization in the Neonatal Period

Portal cavernoma is a major cause of extrahepatic portal hypertension (EHPH) in children. It is a serious condition, due to the frequency and severity of digestive hemorrhages secondary to the rupture of esophageal varices (EV). Neonatal umbilical catheterization is a significant risk factor for the development of portal vein thrombosis (PVT) and portal hypertension. We report a case of a five-year-old male who presented with upper gastrointestinal (GI) bleeding on ruptured esophageal varices resulting from a portal cavernoma, complicating neonatal umbilical vein catheterization. This case illustrates the risk of severe vascular complications, particularly portal hypertension that can result from neonatal umbilical vein catheterization.

A rare case of esophageal variceal bleeding as a result of portal hypertension due to extra-hepatic portal vein obstruction and its management in a 7-year-old

INTRODUCTION

Extrahepatic Portal Vein Obstruction is the most common cause of portal hypertension in children. However, it has a very low prevalence. Esophageal varices due to portal hypertension in children can lead to recurrent episodes of upper gastrointestinal bleeding, which can have a sinister outcome if timely diagnosis and treatment are not initiated.

CASE PRESENTATION

A 7-year-old male child presents with recurrent episodes of upper gastrointestinal bleeding for 3 years. Clinical examination reveals pallor and splenomegaly. Laboratory investigations revealed signs of hypersplenism with anemia, leucopenia and thrombocytopenia, and Doppler ultrasonography and CT abdomen and pelvis revealed splenic vein thrombosis with splenomegaly and cavernous transformation of the portal vein. The patient was managed operatively with splenectomy with splenorenal shunting and devascularization of esophagogastric varices.

DISCUSSION

Extrahepatic Portal Vein obstruction is the most common cause of noncirrhotic portal hypertension in children. Its occurrence in the pediatric population is very rare. Portal hypertension can lead to variceal bleeding and splenomegaly, which can have a significant impact on a child's long-term health. Because of its insidious nature, a meticulous workup is required for its diagnosis, and treatment in the pediatric population is difficult, and appropriate guidelines for its management specifically targeting the pediatric population are lacking.

CONCLUSION

Extrahepatic Portal Vein obstruction is rare in children with a difficult diagnosis and management. Despite these hindrances, timely intervention can lift a significant burden of its detrimental outcome off the young children and drastically uplift the quality of life of these patients.

A systematic review and meta-analysis of portal vein morphometry in pediatric and adult populations: Drawing the line between normal and abnormal findings

PURPOSE

The morphometry of the hepatic portal vein is of clinical importance, particularly in pre-operative assessments, surgical management, and diagnoses of liver conditions. This systematic review and meta-analysis aimed to characterize the morphometry of the normal portal vein in both pediatric and adult patients.

METHODS

The study, conducted using the PRISMA guidelines and registered with PROSPERO, utilized the MEDLINE, EMBASE, SCOPUS and Web of Science databases up to May 2020, and updated to May 2023. All studies reporting extractable data on diameter, length, and cross-sectional area (CSA) of the main, left, and right portal veins (PV, LPV, RPV, respectively) were included. The AQUA Tool was used to assess the quality of the included studies. Data analysis included subgroup analyses based on geographical location, sex, age, and imaging modality.

RESULTS

A total of 122 studies with 11,637 subjects were eligible for inclusion. Overall, the pooled mean diameter of the PV (PVD) was 10.09 mm (95% CI: 9.56-10.62). Significant differences in diameter were found between pediatric (6.60 mm; 95% CI: 5.38-7.82) and adult (10.72 mm; 95% CI: 10.25-11.19) subjects. Additionally, there was a significantly larger PVD measurement from computed tomography (CT) than other imaging modalities: CT, 13.28 mm (95% CI: 11.71-14.84); magnetic resonance imaging (MRI), 10.50 mm (95% CI: 9.35-11.66) and ultrasound (US), 9.81 mm (95% CI: 9.47-10.16). The mean diameters of the LPV and RPV were 8.27 mm (95% CI: 6.78-9.77) and 8.33 mm (95% CI: 6.70-9.95), respectively. Mean PV length in adults is 48.63 mm (95% CI: 35.63-61.64). Mean CSA of the PV was 1.09 cm2.

CONCLUSIONS

The study obtained aim to improve the understanding of portal vein anatomy, especially with relevance to surgical interventions of the liver in both pediatric and adult patients. Measurements from ultrasound imaging closely approximates the generated pooled PVD mean for pediatric and adult patients. CT imaging, however, significantly exceeded the established 13 mm threshold for adults. For pediatric patients, a threshold of 8 mm is proposed as a diagnostic upper limit for a normal PVD. Although not significant, the PVD decreased from the portal confluence towards its bifurcation.

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.

Portal vein thrombosis in a 10-month-old infant as a complication of neonatal umbilical catheterization: a case report

Introduction

Esophageal varices bleeding after portal hypertension is a rare condition in children but is associated with significant morbidity and mortality. Neonatal umbilical catheterization is one of the risk factors for the development of portal vein thrombosis (PVT) and portal hypertension.

Case presentation

Neonatal umbilical catheterization was used here to provide appropriate treatment for postpartum sepsis. Color Doppler revealed an approximate total obstruction of the portal vein, and endoscopy showed esophageal varices. The patient was sequentially managed with endoscopic sclerotherapy.

Discussion

The manifestations associated with PVT (like splenomegaly and bleeding esophageal varices) have been detected in a 10-month-old, which is considered a relatively young age according to the medical literature review.

Conclusion

Using umbilical vein catheterization in neonates may be associated with several complications, including PVT. This case report describes a rare instance of portal hypertension complicated by bleeding esophageal varices in a 10-month-old infant who had undergone newborn umbilical catheterization.

Anticoagulant treatment for pediatric splanchnic vein thrombosis: a systematic review and meta-analysis

BACKGROUND

The clinical characteristics of splanchnic vein thrombosis (SVT) in pediatric patients and its optimal treatment strategies are unknown.

OBJECTIVES

This study aimed to assess the effectiveness and safety of anticoagulant therapy for pediatric SVT.

METHODS

MEDLINE and EMBASE databases were searched up to December 2021. We included observational and interventional studies that enrolled pediatric patients with SVT and reported anticoagulant treatment and outcomes, including rates of vessel recanalization, SVT extension, venous thromboembolism (VTE) recurrence, major bleeding, and mortality. Pooled proportions of vessel recanalization were calculated with their 95% CI.

RESULTS

A total of 506 pediatric patients (aged 0-18 years) across 17 observational studies were included. The majority of patients had portal vein thrombosis (n = 308, 60.8%) or Budd-Chiari syndrome (n = 175, 34.6%). Most events were triggered by transient provoking factors. Anticoagulation (heparins and vitamin K antagonists) was prescribed in 217 (42.9%) patients, and 148 (29.2%) patients underwent vascular interventions. The overall pooled proportions of vessel recanalization were 55.3% (95% CI, 34.1%-74.7%; I2 = 74.0%) among anticoagulated patients and 29.4% (95% CI, 2.6%-86.6%; I2 = 49.0%) among non-anticoagulated patients. SVT extension, major bleeding, VTE recurrence, and mortality rates were 8.9%, 3.8%, 3.5%, and 10.0%, respectively, in anticoagulated patients and 2.8%, 1.4%, 0%, and 50.3%, respectively, in non-anticoagulated patients.

CONCLUSION

In pediatric SVT, anticoagulation appears to be associated with moderate recanalization rates and a low risk of major bleeding. VTE recurrence is low and comparable to that reported in pediatric patients with other types of provoked VTE.

Portal cavernoma in type 1 neurofibromatosis: A fortuitous or causal association?

Neurofibromatosis type 1 (NF-1) is a multisystem genetic disorder affecting the NF1 tumor suppressor gene. Patients typically develop superficial (cutaneous) and internal (plexiform) neurofibromas. The latter may rarely involve the liver locating in the hilum and encasing the portal vessels, leading to portal hypertension. Vascular abnormalities (NF-I vasculopathy) are a well-recognized manifestation of NF-1. Although the pathogenesis is not well-known, NF-1 vasculopathy involves arteries of both peripheral and cerebral territories, with venous thrombosis being exceptionally reported. Portal venous thrombosis (PVT) is the leading cause of portal hypertension in childhood and has been associated with several risk factors. Nevertheless, predisposing conditions remain unknown in more than 50% of the cases. The treatment options are limited, and its management is nonconsensual in the pediatric age. We report the case of a 9-year-old boy with clinically and genetically confirmed NF-1, diagnosed with portal venous cavernoma after an episode of gastrointestinal bleeding. There were no identifiable risk factors for PVT and intrahepatic peri-hilar plexiform neurofibroma was excluded by MRI imaging. To the best of our knowledge, this is the first report of PVT in NF-1. We speculate that NF-1 vasculopathy may have been a pathogenic factor, or instead, it was a fortuitous association.

Frequency of Causes of Portal Hypertension in Children

Introduction

The most common etiology of portal hypertension (PH) in children is obstruction at the presinusoidal or sinusoidal level. In addition, portal vein thrombosis (PVT) and biliary atresia are the most prevalent extrahepatic causes. This study aims to evaluate all the possible etiologies leading to PH in the pediatric population and provide the most common cause associated with this condition along with the age group most frequently affected by it.

Material and Methods

From January 2018 to December 2020, a cross-sectional study was carried out in tertiary care hospitals in Pakistan. A total of 100 children, both male and female, aged one month to 15 years and diagnosed with PH, were enrolled for the evaluation for the causes of PH. The Statistical Package for the Social Sciences (SPSS), version 20, was used to analyze the data.

Results

The mean age of enrolled participants was 9.01 ± 2.81 years. It was found that PVT (63%) was the most common cause of PH, followed by liver cirrhosis (19%) and biliary atresia (18%). Age of more than eight years was significantly associated with PVT (p-value: 0.007).

Conclusion

In children, PH may be caused by a wide range of etiologies. It is imperative to understand the underlying etiologies contributing to PH for proper guidance and management, prevention, and overall outcomes.

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).

Management of Acute Portal Vein Thrombosis With Serial Mechanical Thrombectomy and tPA in a Pediatric Liver Transplant Recipient: A Case Report

BACKGROUND

Acute portal vein thrombosis is a major cause of fulminant allograft failure in pediatric liver transplantation. Timely intervention is critical to save the graft and patient. Serial interventional radiologic management of this condition is scarcely reported in the literature.

CASE SUMMARY

A recently transplanted 17-year-old male presented to the emergency department with abdominal pain. Rising liver enzymes prompted discovery of a diffuse portal thrombus, which precipitated fulminant liver failure. The adolescent developed respiratory failure, vasodilatory shock, acute kidney injury, and hepatic encephalopathy, complicating treatment. Multiple interventions attempted to clear the thrombus, including interventional radiologic and medical therapies. Uniquely, a continuous infusion catheter was placed at the thrombosis, delivering local tissue plasminogen activator during a 5-day period. Upon thrombus clearance, the patient made a full recovery with no complications during 12 months of follow-up.

CONCLUSIONS

When used as a component of multidisciplinary management, continuous locally directed tissue plasminogen activator may be a useful tool for clearance of persistent portal vein thrombosis.

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.

Extrahepatic Portal Vein Thrombosis, an Important Cause of Portal Hypertension in Children

One of the most important causes of portal hypertension among children is extrahepatic portal vein thrombosis (EHPVT). The most common risk factors for EHPVT are neonatal umbilical vein catheterization, transfusions, bacterial infections, dehydration, and thrombophilia. Our study aimed to describe the clinical manifestations, treatment, evolution, and risk factors of children with EHPVT.

METHODS

We analyzed retrospectively all children admitted and followed in our hospital with EHPVT between January 2011-December 2020. The diagnosis was made by ultrasound or contrast magnetic resonance imaging. We evaluated the onset symptoms, complications, therapeutic methods, and risk factors.

RESULTS

A total of 63 children, mean age 5.14 ± 4.90 (33 boys, 52.38%), were evaluated for EHPVT during the study period. The first symptoms were upper gastrointestinal bleeding (31 children, 49.21%) and splenomegaly (22 children, 34.92%). Thrombocytopenia was present in 44 children (69.84%). The most frequent risk factors were umbilical vein catheterization (46 children, 73.02%) and bacterial infections during the neonatal period (30 children, 47.62%). Protein C, protein S, antithrombin III levels were decreased in 44 of the 48 patients tested. In 42 of these cases, mutations for thrombophilia were tested, and 37 were positive. Upper digestive endoscopy was performed in all cases, revealing esophageal varices in 56 children (88.89%). All children with gastrointestinal bleeding received an octreotide infusion. In 26 children (41.27%), variceal ligation was performed, and in 5 children (7.94%), sclerotherapy. Porto-systemic shunt was performed in 11 children (17.46%), and Meso-Rex shunt was done in 4 children (6.35%). The evolution was favorable in 62 cases (98.41%). Only one child died secondary to severe sepsis.

CONCLUSIONS

EHPVT is frequently diagnosed in the last period in our region due to the increased use of umbilical vein catheterization. Furthermore, genetic predisposition, neonatal bacterial infections, and prematurity certainly play an important role in this condition. A proactive ultrasound assessment of children with risk factors for EHPVT should be encouraged for early diagnosis and treatment.

Vascular Anomalies of the Pediatric Liver

The liver is a unique organ as it receives afferent blood supply from the umbilical vein, portal vein, and hepatic artery in the developing embryo but has only one efferent drainage method, through the hepatic veins. In the postnatal period, about 70% of the afferent blood flow into the liver is from the portal venous system, unique vessels that begin and end in a capillary system. Vascular anomalies of the hepatic artery, hepatic veins, portal vein, and/or umbilical vein can be congenital or acquired secondary to inflammation and/or infection, trauma, systemic disorders, or iatrogenic causes. The vascular anomalies can be incidental findings at imaging, or the infant or child can present with symptoms such as abdominal pain and ascites, be diagnosed with gastrointestinal bleeding, and have abnormal liver function test results. Imaging can demonstrate vascular findings such as shunts, thrombosis, or collaterals; secondary parenchymal findings such as diffuse or focal abnormal enhancement patterns; and parenchymal lesions such as regenerative nodules. This article discusses and illustrates vascular disorders of the liver that may be encountered in the pediatric population. These include (a) normal vascular variants; (b) congenital anomalies (preduodenal portal vein and infradiaphragmatic total anomalous pulmonary venous return); (c) acquired thromboses (extrahepatic portal venous thrombosis); (d) inflammatory vascular conditions, which can result in hepatic artery aneurysms or pseudoaneurysms; (e) hepatic venous outflow disorders (veno-occlusive disease); and shunt lesions. Liver transplantation and associated vascular complications are a large topic and will not be reviewed in this article. Knowledge of the vascular and parenchymal changes seen with these entities can aid imaging diagnosis and guide appropriate management. ^©RSNA, 2019.

Recanalization of Chronic Portal Vein Occlusion in Pediatric Liver Transplant Patients

PURPOSE

To evaluate technical and clinical success and report long-term outcomes of portal vein (PV) recanalization in pediatric orthotopic liver transplant (OLT) patients with chronic PV occlusion.

MATERIALS AND METHODS

This is a retrospective review of 15 OLT patients (5 males) with chronic PV occlusion who underwent PV recanalization (33 procedures) between October 2011 and February 2018. Median age was 4.5 years (range, 1-16 years); median weight was 16.6 kg (range, 11.5-57.3 kg). Median time interval from OLT to first intervention was 3.25 years (range, 0.6-15.7 years). Clinical presentations included hypersplenism (n = 12), gastrointestinal bleeding (n = 9), and ascites (n = 3). One patient had incidental diagnosis of PV occlusion. Primary, primary-assisted, and secondary patency at 3, 6, 12, and 24 months were evaluated.

RESULTS

Technically successful PV recanalization and reduction of PV pressure gradient to ≤ 5 mm Hg was performed in 13/15 patients (87%). Ten of 15 (67%) patients had successful recanalization with the first attempt. Clinical success, defined as improvement in signs and symptoms of portal hypertension, was achieved in 12/13 (92%) patients. Five of 33 (15%) major complications (Society of Interventional Radiology class C), including perisplenic hematoma (n = 2), hemoperitoneum (n = 2), and hepatic artery pseudo aneurysm (n = 1), were managed with pain medication and blood product replacement. Median follow-up was 22 months (range, 1-77 months). Median primary patency was 5 months. Primary patency at 3, 6, 12, and 24 months was 53.8%, 46.2%, 38.5%, and 30.8%, respectively. Primary-assisted patency was 84.6%, 76.9%, 53.8%, and 46.2%, respectively. Secondary patency was 92.3%, 84.6%, 53.8%, and 46.2%, respectively.

CONCLUSIONS

PV recanalization is a safe and effective minimally invasive option in the management of chronic PV occlusion after pediatric OLT.

Thrombosis of the Abdominal Veins in Childhood

Abdominal venous thrombosis is a rare form of venous thromboembolic disease in children. While mortality rates are low, a significant proportion of affected children may suffer long-term morbidity. Additionally, given the infrequency of these thrombi, there is lack of stringent research data and evidence-based treatment guidelines. Nonetheless, pediatric hematologists and other subspecialists are likely to encounter these problems in practice. This review is therefore intended to provide a useful guide on the clinical diagnosis and management of children with these rare forms of venous thromboembolic disease. Herein, we will thus appraise the current knowledge regarding major forms of abdominal venous thrombosis in children. The discussion will focus on the epidemiology, presentation, diagnosis, management, and outcomes of (1) inferior vena cava, (2) portal, (3) mesenteric, (4) hepatic, and (5) renal vein thrombosis.

Complications in pediatric endoscopy

The experience of the "endoscopic community" in pediatric patients is limited, but during recent years increased skills of the endoscopists and technological improvements lead to a standardization of pediatric endoscopy and the development of specialized pediatric endoscopy unit. Adverse events related to diagnostic and therapeutic endoscopy in children are usually rare. Diagnosis, prevention and treatment of complications in pediatric endoscopy is crucial when dealing with benign diseases in children. The complication rate of diagnostic EGD and colonoscopy in children are extremely low. Therapeutic procedures have obviously an increased rate of adverse events. Esophageal dilations are the most common indication for endoscopic therapy in children and can lead to perforations which requires prompt diagnosis and management. Complications of ERCP in pediatric age are similar to those reported in adults. The experience in pediatric emergency endoscopy (mainly foreign body removal) is consolidated and related adverse events extremely rare. Sedation of children during endoscopy maybe needs further evaluation and standardization, to reduce the rate of specific complications.

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.