Extrahepatic portal vein thrombosis in children and adolescents: Influence of genetic thrombophilic disorders

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 History of Umbilical Vein Catheterization Does Not Preclude Children from a Successful Meso-Rex Bypass

INTRODUCTION

 Umbilical vein catheterization (UVC) can cause portal venous thrombosis, leading to the development of extrahepatic portal venous obstruction (EHPVO) and portal hypertension (PHT). The feasibility of the Meso-Rex bypass (MRB) for the treatment of EHPVO in patients with a history of UVC has been questioned. We compared the feasibility of performing an MRB in patients with or without a history of previous UVC.

METHODS

 A retrospective review of patients with EHPVO and known UVC status explored for a possible MRB at our institution was performed (1997-2022). Patients were categorized in two groups: with (UVC(+)) or without (UVC(-)) a history of UVC for comparison. A p-value less than 0.05 was considered significant.

RESULTS

 One hundred and eighty-seven patients were included (n = 57 in UVC(+); n = 130 in UVC(-)). Patients in the UVC group were significantly younger at surgery and the incidence of prematurity was higher. Other risk factors for the development of EHPVO were similar between the groups, but only history of UVC could predict the ability to receive MRB (odds ratio [OR]: 7.4 [3.5-15.4]; p < 0.001). The success rate of MRB was significantly higher in patients with no history of UVC (28/57 [49.1%] in UVC(+) vs. 114/130 [87.7%] in UVC(-); p < 0.001). However, MRB patency at discharge (25/28 [89.3%] in UVC(+) vs. 106/114 [94.7%] in UVC(-); p = 0.3) was equally high in both groups.

CONCLUSION

 Our results indicate that a history of UVC is not a contraindication to MRB. Half of the patients were able to successfully receive an MRB. Patients with symptomatic PHT from EHPVO should not be excluded from consideration for MRB based on UVC history.

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.

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.

Functional side-to-side splenorenal shunts to treat extrahepatic portal vein thrombosis in children

BACKGROUND

Surgical shunts are commonly used to manage complications resulting from extrahepatic portal vein thrombosis (EHPVT) in children. We describe a single-center experience utilizing a functional Side-to-Side Splenorenal Shunt (fSRS), created using either an enlarged inferior mesenteric vein (IMV) or left adrenal vein (LAV).

METHODS

Pediatric patients with isolated EHPVT who were poor candidates for a Rex shunt and who underwent a fSRS procedure at our institution between 2003 and 2020 were reviewed. The pre/post shunt portosystemic gradient change, rates of early and late complications, postoperative shunt patency, and mortality were evaluated.

RESULTS

Twelve EHPVT patients (mean age of 6.1 years) underwent a fSRS procedure. The mean portosystemic gradient change for the cohort was -11.7 mmHg (±4.9). There were no cases of recurrent variceal bleeding or episodes of shunt thrombosis reported after fSRS procedures.

CONCLUSIONS

Surgical shunts continue to be an important adjunct in the treatment of complications related to EHPVT. The functional Side-to-Side Splenorenal Shunt is a safe alternative that is easy to perform, involves minimal dissection and requires only a single anastomosis.

Extrahepatic Portal Vein Thrombosis in Childhood: Risk Factors, Clinical Manifestations, and Management

OBJECTIVE

Extrahepatic portal vein thrombosis (EHPVT) is a common cause of portal hypertension in children. The aim of the present study was to identify the clinical manifestations and the risk factors for development of EHPVT in pediatric patients.

SUBJECTS AND METHODS

This was a single-center retrospective cohort study. A total of 12 children (6 boys and 6 girls) took part in the study. We noted the clinical presentations and the predisposing risk factors for development of EHPVT in all patients. In addition, as all of them had undergone an esophagogastroduodenoscopy for detection and grading of esophageal varices as part of the treatment algorithm, we analyzed the endoscopic findings and the therapeutic approach.

RESULTS

The median age of subjects at diagnosis was 3.5 years (range: 1-17 years). The most frequent initial clinical manifestation was upper gastrointestinal bleeding (6 cases, 50.0%) followed by splenomegaly (3 cases, 25.0%). The most frequent systemic risk factor for EHPVT was presence of inherited prothrombotic disorder (10 cases, 83.3%), and the most common local risk factor for EHPVT was umbilical vein catheterization (5 cases, 41.7%). Esophageal varices were revealed in all the study participants, and in the most cases, they were grade ≥2. Propranolol was used as primary or secondary prophylaxis in 7 children (58.3%), and in 5 children (41.7%), a shunt was performed (Meso-Rex bypass in 3 children and splenorenal shunt in 2 children).

CONCLUSION

Patients with known systemic or local risk factors for EHPVT are indicated for proactive ultrasound screening for early diagnosis and timely management.

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.

Surgical shunts for extrahepatic portal vein obstruction in pediatric patients: a systematic review

BACKGROUND

Extrahepatic portal vein obstruction (EHPVO) causes portal hypertension in noncirrhotic children. Among surgical treatments, it is unclear whether the meso-Rex shunt (MRS) or portosystemic shunt (PSS) offers lower post-operative morbidity and superior patency over time. Our objective was to evaluate long-term outcomes comparing MRS and PSS for pediatric patients with EHPVO.

METHODS

A systematic review was conducted of articles reporting children undergoing surgical shunts for EHPVO from 1/2000-2/2020. Of 87 articles screened, 22 were eligible for inclusion. The primary outcome was shunt thrombosis and secondary outcomes included non-operative complications, stenosis, and re-operation.

RESULTS

Eighteen of 22 studies were of good quality and four had fair quality. Of 461 patients included, 340 underwent MRS and 121 underwent PSS. MRS were associated with a higher rate of post-operative thrombosis when compared to PSS (14.1% vs 5.8%, p = 0.021). There were 40/340 MRS patients (11.8%) that required at least one re-operation for either shunt thrombosis or stenosis, versus 5/121 PSS patients (4.1%), p = 0.019.

CONCLUSION

Both MRS and PSS result in acceptable long-term patency rates, but the more technically demanding MRS is associated with higher post-shunt thrombosis, often requiring further operative intervention. This study suggests that PSS may offer advantages for pediatric patients with EHPVO.

Thromboelastography Detects Possible Coagulation Disturbance in Pediatric Patients with Portal Cavernoma

Background

Thromboelastography (TEG) allows a dynamic assessment of clot formation and dissolution that might be useful for assessing the relative contribution of the coagulation components to overall clot formation and dissolution, but it has not been fully defined in patients with portal cavernoma (PC).

Methods

We retrospectively recruited consecutive patients with PC between July 2006 and June 2016 who had no abdominal malignancy or liver cirrhosis. Blood samples were drawn on admission and were subjected to coagulation parameter assessment, including conventional coagulation tests, measurement of the circulating levels of procoagulant and anticoagulant factors, and TEG assessment.

Results

Compared with controls, patients with PC showed significant reductions in the serum levels of procoagulant factors and anticoagulants factors, whereas factor VIII was slightly elevated. TEG showed clot formation (α-angle), and the maximal clot strength (MA) was higher in patients with PC than in controls, indicating a hypercoagulable state. Thrombocytopenia decreased both clot formation (α-angle) and the maximal clot strength (MA) but was still significantly higher than the control. Furthermore, patients with PC had a higher level of D-dimer and LY30 than did controls, indicating the in vivo activation of coagulation and fibrinolysis.

Conclusion

TEG analysis showed that patients with PC were in a hypercoagulable state that could be partially masked by thrombocytopenia secondary to splenomegaly and hypersplenism in these patients, which indicates that our current prophylaxis and therapy regimen could be improved.

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.

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.

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.

Ammonia toxicity to the brain

Hyperammonemia can be caused by various acquired or inherited disorders such as urea cycle defects. The brain is much more susceptible to the deleterious effects of ammonium in childhood than in adulthood. Hyperammonemia provokes irreversible damage to the developing central nervous system: cortical atrophy, ventricular enlargement and demyelination lead to cognitive impairment, seizures and cerebral palsy. The mechanisms leading to these severe brain lesions are still not well understood, but recent studies show that ammonium exposure alters several amino acid pathways and neurotransmitter systems, cerebral energy metabolism, nitric oxide synthesis, oxidative stress and signal transduction pathways. All in all, at the cellular level, these are associated with alterations in neuronal differentiation and patterns of cell death. Recent advances in imaging techniques are increasing our understanding of these processes through detailed in vivo longitudinal analysis of neurobiochemical changes associated with hyperammonemia. Further, several potential neuroprotective strategies have been put forward recently, including the use of NMDA receptor antagonists, nitric oxide inhibitors, creatine, acetyl-L-carnitine, CNTF or inhibitors of MAPKs and glutamine synthetase. Magnetic resonance imaging and spectroscopy will ultimately be a powerful tool to measure the effects of these neuroprotective approaches.

Acquired and Heritable Thrombophilia in Indian Patients With Pediatric Deep Venous Thrombosis (DVT)

Deep venous thrombosis (DVT) in children is more often associated with underlying pathological conditions than with hereditary thrombophilia. The present study is a retrospective analysis of thrombophilia in 285 pediatric patients with venous thrombosis at different sites. Four common thrombophilia markers, that is protein C, protein S, antithrombin III, and factor V Leiden (FVL) mutation, were analyzed. Thrombosis in hepatic and portal veins was more common in pediatric patients (73%) when compared to other sites (27%). Overall, hereditary thrombophilia accounted for 15.5% of the patients with venous thrombosis. The FVL mutation, which was the major causative factor in Budd-Chiari syndrome and portal vein thrombosis cases in the adult group, was not a major contributing factor in pediatric group, that is, 1.8% of the patients. In conclusion, the risk factors for venous thrombosis vary in different age groups.

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.

Surgical management of portal hypertension in children

The management of children with portal hypertension has dramatically changed during the past decade, with an improvement in outcome. This has been achieved by improved efficiency of endoscopic variceal control and the success of liver transplantation. Emergency surgical shunt procedures are rarely required, with acute bleeding episodes generally controlled endoscopically or, occasionally in adults, by interventional radiological procedures. Portosystemic shunts may be considered as a bridge to transplant in adults but are rarely used in this context in children. Nontransplant surgery or radiological interventions may still be indicated for noncirrhotic portal hypertension when the primary cause can be cured and to allow normalization of portal pressure before liver parenchyma is damaged by chronic secondary changes in some specific diseases. The meso-Rex bypass shunt is used widely but is limited to those with a favorable anatomy and can even be performed preemptively. Elective portosystemic shunt surgery is reserved for failure to respond to conservative management in the absence of alternative therapies.

Progression of noncirrhotic portal hypertension in a pediatric population

BACKGROUND/OBJECTIVES

The optimal management of children with noncirrhotic portal hypertension is controversial. Some groups suggest early and aggressive surgical intervention, while others report long-term success with conservative management.

METHODS

We conducted a retrospective study of 26 patients with noncirrhotic portal hypertension treated at our institution. We compared platelet counts, white blood cell (WBC) counts, spleen size, hospital admissions, gastrointestinal bleeds, and longitudinal trends of specific clinical parameters using standard univariate and time-trend analytic techniques.

RESULTS

Mean age at the time of diagnosis was 5.2 years. Portal vein thrombosis was found in 84.6% of patients (n=22). There was one mortality related to malignancy. There was not a progression of hypersplenism in patients that did not receive a shunt and conversely, we did not notice a significant decrease in spleen size following shunt surgery (P=0.2). Platelet and WBC counts trended downward among patients managed medically, while platelets increased and WBC counts remained stable in surgical patients. There was a significant decrease in hospital admissions for gastrointestinal bleeding following surgical intervention in the shunt group compared with nonshunt (P=0.0009).

CONCLUSION

While our analysis was limited given small sample sizes and selection bias, it suggests that the majority of pediatric patients with noncirrhotic portal hypertension will do well long-term without surgical intervention.

Neonatal portal vein thrombosis: diagnosis and management

Neonatal portal vein thrombosis (PVT) is an increasingly recognized event. Patients are generally asymptomatic in the neonatal period. The diagnosis is made with Doppler ultrasound. Umbilical catheterization, exchange transfusion and sepsis are risk factors for neonatal PVT. Thrombophilia is possibly a contributing risk factor. Although there are potential serious acute complications such as hepatic necrosis, the outcome is good in the majority of cases, followed up to 8 years of age. Thrombus resolution occurs in 30-70% in days to months. Liver lobe atrophy may occur following PVT, and does not appear to be associated with any impairment of liver function. Non-occlusive thrombosis is more likely to resolve than non-occlusive thrombosis. A subset of patients without resolution is at risk for developing portal hypertension over the next decade of life. There are no current defining features present during the neonatal period to enable identification of neonates at risk for portal hypertension. There is no evidence that anticoagulation therapy improves time to resolution or decreases the likelihood of portal hypertension. Anticoagulation therapy may be considered. A management algorithm is proposed.

High incidence of hepatitis B infection-associated cirrhosis and hepatocellular carcinoma in the Southeast Asian patients with portal vein thrombosis

Background

Portal vein thrombosis (PVT) is a rare condition associated with serious morbidity and mortality. The objective of this study was to determine the frequency, clinical presentations, and risk factors of PVT from the set of data firstly collected among the Southeast Asian population.

Methods

A retrospective study was undertaken to identify patients diagnosed with thrombosis of the portal system and other abdominal veins. The hospital medical records were retrieved based on the selected ICD-10 codes. Clinical presentations were collected and risk factors determined.

Results

From 2000-2009, 467 hospital charts with designated ICD-10 codes of I81, I82.2, I82.3, I82.8, I82.9, or K55.0 were identified. PVT (I81) was the most common thrombosis (194 cases, 41.54%). The majority of PVT patients were males (65%), older than 40 years (75%), and presented with abdominal distension/ascites (69%), splenomegaly (54.6%), and abdominal pain (50.5%). Overall, the predominant risk factor was hepatocellular carcinoma (HCC) (52.5%), followed by liver cirrhosis without cancer (9.3%), abdominal infection/inflammation (9.3%), cholangiocarcinoma (8.2%), and abdominal intervention (7.7%). In young patients, abdominal interventions including umbilical catheterization (23.1%) and hepatectomy (7.7%) were the most frequent risks whereas in older cases, primary hepatobiliary cancer and cirrhosis (78%) were the major risks. Liver metastases from other organs were infrequently found. Chronic hepatitis B virus (HBV) infection was the main etiology associated with cirrhosis/HCC leading to PVT in this cohort. A third of the older PVT patients (age >40) had HBV and very few carried hepatitis C virus (HCV) whereas none of the young PVT patients (age <20) had HBV or HCV. A variety of abdominal infections/inflammations were also found including liver abscess, splenic abscess, cholangitis, cholecystitis, pancreatitis, omphalitis, and abdominal tuberculosis. Single cases of systemic lymphangiomatosis and Klippel-Trénaunay vascular malformation syndrome were also identified. Other thrombophilic conditions such as myeloproliferative neoplasms, paroxysmal nocturnal hemoglobinuria, protein S deficiency, and anti-phospholipid syndrome were rarely encountered.

Conclusion

HBV is the major risk of PVT in the Southeast Asian population. Several risk factors identified in this population have rarely been described and some are remarkably different from those reported in the West. Host and environmental factors may play a causal role in the initiation and development of PVT in various ethnicities and geographic locations.