Study of portal vein thrombosis in patients with idiopathic portal hypertension in Japan

Prevalence of portal vein thrombosis in pediatric patients with cirrhosis and intrahepatic non-cirrhotic portal hypertension

INTRODUCTION

Portal vein thrombosis (PVT) has been increasingly diagnosed in pediatric patients owing to the widespread use of non-invasive radiological techniques. Although the prevalence of PVT in adults with cirrhosis and intrahepatic non-cirrhotic portal hypertension ranges from 0.6 to 26 % and 13 to 46 %, respectively, no available data exist in the pediatric population. The prevalence of PVT in children with cirrhotic and intrahepatic non-cirrhotic portal hypertension was evaluated in this study.

METHODS

This retrospective study included children with cirrhosis and intrahepatic non-cirrhotic portal hypertension, which consisted of congenital hepatic fibrosis (CHF) and idiopathic noncirrhotic portal hypertension (INCPH). Patients with extrahepatic portal venous obstruction were excluded from the study. The presence of PVT was evaluated using abdominal Doppler ultrasonography and/or CT. Etiological, clinical, and laboratory findings were compared between the groups.

RESULTS

One hundred and forty-two patients with cirrhosis (mean admission age: 64.6 months ± 66.4, mean follow-up duration: 46.8 months ± 45.6) and 41 patients with non-cirrhotic patients (CHF=16, INCPH = 25, mean admission age: 126 months ± 64.2) were enrolled in this study. The prevalence of PVT was not significantly different between cirrhotic (8.5 %) and non-cirrhotic (9.7 %) patients. The incidence of PVT was significantly higher in patients with biliary atresia than in those with other etiologies in the cirrhotic group (p = 0.022). The frequency of PVT was higher in patients who had Child-Pugh score ≥7 in the cirrhotic group, but the difference was not statistically significant (p = 0066). The PVT group required more liver transplantations than the non-PVT group (p = 0.038).

CONCLUSION

The prevalence of PVT was similar in pediatric patients with cirrhosis and intrahepatic non-cirrhotic portal hypertension in our cohort, which is compatible with adult studies. Biliary atresia is found to be an important risk factor for PVT in our pediatric population. It might be associated with rapid progression of the disease, ascending cholangitis, and embryological abnormalities. These patients should be routinely evaluated to identify portal vein complications and early warning signs during follow-up.

Hepatopulmonary syndrome in patients with porto-sinusoidal vascular disorder: Characteristics and outcome

Background & Aims

Porto-sinusoidal vascular disorder (PSVD) is a rare cause of portal hypertension. Data on hepatopulmonary syndrome (HPS) in PSVD are limited. This study aimed to determine the associated factors, plasma mediators, and evolution of HPS in patients with PSVD.

Methods

Multicenter observational study of patients with PSVD with signs of portal hypertension in whom contrast-enhanced transthoracic echocardiography (CE-TTE) was performed.

Results

Among 196 patients with PSVD who underwent CE-TTE in 17 centers, 14 (7% [95% confidence interval 3-11%]) had a confirmed diagnosis of HPS. Patients with HPS more frequently had a genetic disorder associated with PSVD (50% vs. 6%, p <0.001), especially telomere biology disorders (p <0.001). Liver function was less preserved in patients with HPS, because they had lower prothrombin index (63% vs. 86%, p = 0.04), higher serum total bilirubin (37 μmol/L vs. 14 μmol/L, p <0.001), and lower serum albumin (32 g/L vs. 38 g/L, p <0.001). HPS tended to be associated with more portal venule obliterations (p = 0.085) and with nodular liver architecture (p = 0.069). Plasma concentrations of Angiopoietin-2, ICAM3, and Tie2 were higher in patients with HPS (p = 0.02, p = 0.04, p = 0.01, respectively). Out of the 14 patients with HPS, five underwent liver transplantation after a median follow-up of 34 months. Overall cumulative incidence of liver-related events and of death was similar between patients with and without HPS, when considering liver transplantation for HPS as a competing risk.

Conclusions

HPS in patients with PSVD was associated with genetic disorders, less preserved liver function, and higher plasma concentrations of angiogenic mediators. When applying HPS model for end-stage liver disease exception policy for liver transplantation, overall survival of patients with PSVD and HPS was similar to that of patients with PSVD without HPS.

Impact and implications

Hepatopulmonary syndrome (HPS) is a rare complication of porto-sinusoidal vascular disorder (PSVD). This multicentric study found that patients with PSVD and HPS had less preserved liver function, and harbored genetic disorders more frequently (especially telomere biology disorders) than patients without HPS. HPS did not negatively impact transplantation-free survival when applying HPS MELD exception policy for liver transplantation through a competitive risk analysis. Our findings suggest that patients with PSVD with respiratory symptoms and/or telomere biology disorders may benefit from systematic screening for HPS.

Portal hypertension: recommendations for diagnosis and treatment. Consensus document sponsored by the Spanish Association for the Study of the Liver (AEEH) and the Biomedical Research Network Centre for Liver and Digestive Diseases (CIBERehd)

Portal hypertension is a hemodynamic abnormality that complicates the course of cirrhosis, as well as other diseases that affect the portal venous circulation. The development of portal hypertension compromises prognosis, especially when it rises above a certain threshold known as clinically significant portal hypertension (CSPH). In the consensus conference on Portal Hypertension promoted by the Spanish Association for the Study of the Liver and the Hepatic and Digestive diseases area of the Biomedical Research Networking Center (CIBERehd), different aspects of the diagnosis and treatment of portal hypertension caused by cirrhosis or other diseases were discussed. The outcome of this discussion was a set of recommendations that achieved varying degrees of consensus among panelists and are reflected in this consensus document. The six areas under discussion were: the relevance of CSPH and the non-invasive methods used for its diagnosis and that of cirrhosis, the prevention of the first episode of decompensation and its recurrence, the treatment of acute variceal bleeding and other complications of portal hypertension, the indications for the use of TIPS, and finally, the diagnosis and treatment of liver vascular diseases.

Portal hypertension: recommendations for diagnosis and treatment. Consensus document sponsored by the Spanish Association for the Study of the Liver (AEEH) and the Biomedical Research Network Center for Liver and Digestive Diseases (CIBERehd)

Portal hypertension is a hemodynamic abnormality that complicates the course of cirrhosis, as well as other diseases that affect the portal venous circulation. The development of portal hypertension compromises prognosis, especially when it rises above a certain threshold known as clinically significant portal hypertension (CSPH). In the consensus conference on Portal Hypertension promoted by the Spanish Association for the Study of the Liver and the Hepatic and Digestive diseases area of the Biomedical Research Networking Center (CIBERehd), different aspects of the diagnosis and treatment of portal hypertension caused by cirrhosis or other diseases were discussed. The outcome of this discussion was a set of recommendations that achieved varying degrees of consensus among panelists and are reflected in this consensus document. The six areas under discussion were: the relevance of clinically significant portal hypertension and the non-invasive methods used for its diagnosis and that of cirrhosis, the prevention of the first episode of decompensation and its recurrence, the treatment of acute variceal bleeding and other complications of portal hypertension, the indications for the use of TIPS, and finally, the diagnosis and treatment of liver vascular diseases.

[Portosinusoidal vascular disorder: A paradigm shift]

The term portosinusoidal vascular disorder (PSVD) refers to a clinical-pathological entity that encompasses those patients with intrahepatic vascular damage without cirrhosis at risk of developing severe complications of portal hypertension. Numerous systemic diseases, genetic disorders, and toxic agents have been associated with this pathology, making its diagnosis an important clinical challenge. The recent description of uniform diagnostic criteria and a better understanding of its pathophysiology will allow for better identification of patients, even in early stages of the disease. Although there is currently no effective etiological treatment available, early diagnosis allows for the development of preventive strategies for some severe complications of portal hypertension.

Portosinusoidal Vascular Disorder: A Heretofore Unrecognized Manifestation of Sickle Cell Disease?

Portosinusoidal vascular disorder (PSVD) is a recently proposed histopathologic entity that encompasses a spectrum of often subtle hepatic microvascular lesions and related microarchitectural abnormalities. Clinical manifestations may arise years after histologic diagnosis and include extrahepatic portal vein thrombosis and portal hypertension. While the histopathologic features of PSVD have been associated with numerous clinical conditions, most notably prothrombotic/vasculopathic disorders, PSVD has not yet been described in sickle cell disease. This gap is striking given the central role of microvascular dysfunction in sickle cell disease and well-described patterns of hepatic injury and dysfunction in this population. This case series is the first to explore the prevalence and pathogenesis of PSVD in sickle cell disease. Forty-one diagnostically adequate liver biopsies from patients with sickle cell disease were identified across the archives of 5 tertiary medical centers. All biopsies exhibited at least 1 histopathologic feature associated with PSVD (mean 3.8 features/case). Overall, 90.2% of patients met the criteria for a diagnosis of PSVD based on the presence of specific histopathologic and/or clinical findings. Immunohistochemical stains for von Willebrand factor, CD34, and glutamine synthetase were performed on 36 cases (87.8%). Aberrant (centrilobular sinusoidal) CD34 and von Willebrand factor staining was present in 97.2% and 86.1% of cases, respectively. Glutamine synthetase reactivity was at least mildly decreased in zone 3 hepatocytes in 52.8% of cases. We posit that chronic erythrocyte sickling results in dysfunction and remodeling of the portal microvasculature, culminating in regression of zone 3 hepatocytes. The presence of PSVD may explain, at least in part, the hepatic dysfunction observed in this patient population. These patients may also benefit from extended clinical surveillance for portal hypertension and other complications. While subtle and prone to overdiagnosis, the features of PSVD should be carefully considered when interpreting liver biopsies from patients with sickle cell disease.

Paediatric porto-sinusoidal vascular disease: Two different clinical phenotypes with subtle histological differences

BACKGROUND AND AIMS

In paediatrics, porto-sinusoidal vascular disease (PSVD) is relatively unknown and probably underdiagnosed. We aimed to describe clinical phenotypes, histology and outcome of children diagnosed with PSVD.

METHODS

Retrospective multicentre study of children diagnosed with PSVD. Diagnosis of PSVD was based on histopathology reports; liver specimens were re-evaluated by two expert liver pathologists.

RESULTS

Sixty two children diagnosed with PSVD (M/F = 36/26, median age 6.6 years, range 3.3-10.6), from 7 centres, were included. Thirty-six presented with non-cirrhotic portal hypertension, PH, (PH-PSVD Group = 58%) while 26 had a liver biopsy because of chronic elevation of transaminases without PH (noPH-PSVD Group = 42%). On histology review, the two groups differed for the prevalence of obliterative portal venopathy (more prevalent in PH-PSVD, p = 0.005), and hypervascularised portal tracts (more common in noPH-PSVD, p = 0.039), the other histological changes were equally distributed. At multivariate analysis, platelet count ≤185 000/mm3 was the only independent determinant of PH (p < 0.001). After a median follow-up of 7 years (range 3.0-11.2), in PH-PSVD group 3/36 (8%) required TIPS placement, 5/36 (14%) developed pulmonary vascular complications of PH, and 7/36 (19%) required liver transplantation. In noPH-PSVD none progressed to PH nor had complications.

CONCLUSIONS

Paediatric patients with PSVD present with two different clinical phenotypes, one characterised by PH and one by chronic elevation of transaminases without PH. PSVD should be included among the conditions causing isolated hypertransaminasaemia. On histology, the differences between the two groups are subtle. Medium-term outcome is favourable in patients without PH; progression of the disease is observed in those with PH.

Portal vein thrombosis, hepatic decompensation, and survival in patients with porto-sinusoidal vascular disease and portal hypertension

BACKGROUND

Porto-sinusoidal vascular disease (PSVD) is a novel nomenclature to describe non-cirrhotic portal hypertension and characteristic histology without portal vein thrombosis (PVT). It is a more inclusive definition than the previously well-recognized entity idiopathic non-cirrhotic portal hypertension. There is a paucity of data on PSVD patients.

METHODS

A total of 33 patients diagnosed with PSVD and portal hypertension (PH) between 2005 and 2021 were included. Data were retrieved from electronic medical record system and analyzed.

RESULTS

Of the 33 patients, 6 (18%) occurred in post-transplant allograft liver. After a median follow-up of 96 months (interquartile range, IQR [52, 139]), 14 deaths occurred (42%), 4 directly related to decompensated liver disease. The Kaplan-Meier survival estimates at 1, 5, and 10 years were 94%, 87% and 58%. PVT occurred in 10 patients (30%). The Nelson-Aalen cumulative risk estimate for PVT at 1, 5 and 10 years were 16%, 25% and 48%. The median model for end-stage liver disease and Child-Pugh score at initial presentation were 8 (IQR [7-12]) and 5 [5-6], and increased to 13 [8, 18] and 7 [5, 8], respectively, at the end of follow-up. Of the 11 patients who presented with splenomegaly and no specific sign of PH, 7 (64%) developed varices and 3 (27%) ascites at a median follow-up of 100 months.

CONCLUSIONS

PSVD with PH is not a benign entity. Mortality, PVT and hepatic decompensation are common. Patients with PSVD must be closely monitored, including those who only have non-specific clinical signs (e.g., splenomegaly) of PH.

Epidemiology of portal vein thrombosis in liver cirrhosis: A systematic review and meta-analysis

BACKGROUND

Portal vein thrombosis (PVT) may be associated with negative outcomes in patients with liver cirrhosis. However, the prevalence and incidence of PVT in liver cirrhosis are heterogeneous among studies and have not been sufficiently determined yet.

METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched. Eligible studies would explore the prevalence and/or incidence of PVT in liver cirrhosis without hepatocellular carcinoma or abdominal surgery. Pooled proportion with 95% confidence interval (CI) was calculated using a random-effect model. Factors associated with the presence/occurrence of PVT were also extracted.

RESULTS

Among the 8549 papers initially identified, 74 were included. Fifty-four studies explored the prevalence of PVT in liver cirrhosis with a pooled prevalence of 13.92% (95%CI=11.18-16.91%). Based on cross-sectional data, Child-Pugh class B/C, higher D-dimer, ascites, and use of non-selective beta-blockers (NSBBs) were associated with the presence of PVT in liver cirrhosis. Twenty-three studies explored the incidence of PVT in liver cirrhosis with a pooled incidence of 10.42% (95%CI=8.16-12.92%). Based on cohort data, Child-Pugh class B/C, higher model of end-stage liver disease score, higher D-dimer, lower platelets count, decreased portal flow velocity, ascites, use of NSBBs, and moderate or high-risk esophageal varices could predict the occurrence of PVT in liver cirrhosis.

CONCLUSION

Approximately one seventh of cirrhotic patients have PVT, and one tenth will develop PVT. Progression of liver cirrhosis and portal hypertension seems to be in parallel with the risk of PVT. Prospective studies with detailed information about classification and extension of PVT in liver cirrhosis are needed.

Porto-sinusoidal vascular disorder

It is well established that portal hypertension can occur in the absence of cirrhosis, as reported in patients with immune disorders, infections and thrombophilia. However, similar histological abnormalities primarily affecting the hepatic sinusoidal and (peri)portal vasculature have also been observed in patients without portal hypertension. Thus, the term porto-sinusoidal vascular disorder (PSVD) has recently been introduced to describe a group of vascular diseases of the liver featuring lesions encompassing the portal venules and sinusoids, irrespective of the presence/absence of portal hypertension. Liver biopsy is fundamental for PSVD diagnosis. Specific histology findings include nodular regenerative hyperplasia, obliterative portal venopathy/portal vein stenosis and incomplete septal fibrosis/cirrhosis. Since other conditions including alcohol-related and non-alcoholic fatty liver disease, or viral hepatitis, or the presence of portal vein thrombosis may occur in patients with PSVD, their relative contribution to liver damage should be carefully assessed. In addition to histology and clinical diagnostic criteria, imaging and non-invasive tests such as liver and spleen stiffness measurements could aid in the diagnostic workup. The introduction of PSVD as a novel clinical entity will facilitate collaborative studies and investigations into the underlying molecular pathomechanisms encompassed by this term.

Contrast-enhanced CT and liver surface nodularity for the diagnosis of porto-sinusoidal vascular disorder: A case-control study

BACKGROUND AND AIMS

Porto-sinusoidal vascular disorder (PSVD) is a rare and commonly overlooked cause of portal hypertension. The interest of CT analysis, including quantification of liver surface nodularity (LSN) for PSVD diagnosis has not been established. This study aimed at assessing the performance of LSN and CT features for a PSVD diagnosis in patients with signs of portal hypertension.

APPROACH AND RESULTS

This retrospective case-control study included a learning cohort consisting of 50 patients with histologically proven PSVD, according to VALDIG criteria, and 100 control patients with histologically proven cirrhosis, matched on ascites. All patients and controls had at least one sign of portal hypertension and CT available within 1 year of liver biopsy. Principal component analysis of CT features separated patients with PSVD from patients with cirrhosis. Patients with PSVD had lower median LSN than those with cirrhosis (2.4 vs. 3.1, p < 0.001). Multivariate analysis identified LSN < 2.5 and normal-sized or enlarged segment IV as independently associated with PSVD. Combination of these two features had a specificity of 90% for PSVD and a diagnostic accuracy of 84%. Even better results were obtained in an independent multicenter validation cohort including 53 patients with PSVD and 106 control patients with cirrhosis (specificity 94%, diagnostic accuracy 87%).

CONCLUSIONS

This study that included a total of 103 patients with PSVD and 206 patients with cirrhosis demonstrates that LSN < 2.5 combined with normal-sized or enlarged segment IV strongly suggests PSVD in patients with signs of portal hypertension.

Idiopathic Non-Cirrhotic Portal Hypertension and Porto-Sinusoidal Vascular Disease: Review of Current Data

Idiopathic non-cirrhotic portal hypertension (INCPH) is a clinicopathologic disease entity characterized by the presence of clinical signs and symptoms of portal hypertension (PH) in the absence of liver cirrhosis or known risk factors accountable for PH. Multiple hematologic, immune-related, infectious, hereditary and metabolic risk factors have been associated with this disorder. Still, the exact etiopathogenesis is largely unknown. The recently proposed porto-sinusoidal vascular disease (PSVD) scheme broadens the spectrum of the disease by also including patients without clinical PH who are found to have similar histopathologic findings on core liver biopsies. Three histomorphologic lesions have been identified as specific for PSVD to include obliterative portal venopathy, nodular regenerative hyperplasia and incomplete septal cirrhosis/fibrosis. However, these findings are often subtle, under-recognized and subjective with low interobserver agreement among pathologists. Additionally, the natural history of the subclinical forms of the disease remains unexplored. The clinical course is more favorable compared to cirrhosis patients, especially in the absence of clinical PH or liver dysfunction. There are no universally accepted guidelines in regard to diagnosis and treatment of INCPH/PSVD. Hence, this review emphasizes the need to raise awareness of this entity by highlighting its complex pathophysiology and clinicopathologic associations. Lastly, formulation of standardized diagnostic criteria with clinical validation is necessary to avoid misclassifying vascular diseases of the liver and to develop and implement targeted therapeutic strategies.

Diagnostic challenges in non-cirrhotic portal hypertension - porto sinusoidal vascular disease

Non-cirrhotic portal hypertension consists of a group of diseases characterized by signs and complications of portal hypertension, which differ from cirrhosis through histological alterations, hemodynamic characterization and, clinical outcome. Because of the similarities in clinical presentation and imaging signs, frequently these patients, and particularly those with porto-sinusoidal vascular disease (PSVD), are misdiagnosed as having liver cirrhosis and thus raising difficulties in their diagnosis. The most challenging differentiation to be considered is between PSVD and cirrhosis and, although not pathognomonic, liver biopsy is still the standard of diagnosis. Although they still require extended validation before being broadly used, new non-invasive methods for the diagnosis of porto-sinusoidal vascular disease, like transient elastography, contrast-enhanced ultrasound or metabolomic profiling, have shown promising results. Another issue is the differentiation between PSVD and chronic extrahepatic portal vein obstruction, especially now when it is known that 40% of patients suffering from PSVD develop portal vein thrombosis. In this particular case, once the portal vein thrombosis occurred, the diagnosis of PSVD is impossible according to the current guidelines. Moreover, so far, the differentiation between PSVD and sinusoidal obstruction syndrome has not been clear so far in particular circumstances. In this review we highlighted the diagnostic challenges regarding the PSVD, as well as the current techniques used in the evaluation of these patients.

Porto-sinusoidal vascular disease: proposal and description of a novel entity

Portal hypertension in the absence of portal vein thrombosis and without cirrhosis, but with mild or moderate alterations of liver histology (eg, obliterative venopathy, nodular regenerative hyperplasia, or incomplete septal cirrhosis) is being increasingly recognised. Owing to the heterogeneity of causes and histological findings, a substantial number of terms have been used to describe such idiopathic non-cirrhotic portal hypertension. Patients with the same clinical and histological features exist, but without portal hypertension at the time of diagnosis. Therefore, improved criteria are needed to define this form of liver disease. Here, we propose the term porto-sinusoidal vascular disease, since all lesions found involve the portal venules or sinusoids. The definition of this entity is based on the characteristic absence of cirrhosis with or without signs of portal hypertension or histological lesions. The presence of known causes of liver disease does not rule out porto-sinusoidal vascular disease, but specific causes of vascular liver disease are excluded from its definition. The diagnosis of porto-sinusoidal vascular disease is based on liver biopsy and might include signs specific for portal hypertension with normal or mildly elevated liver stiffness values and no complete portal vein thrombosis. We provide simple diagnostic criteria, because agreement on a uniform nomenclature is an essential requirement for future collaborative studies.

Imaging and Pathological Features of Idiopathic Portal Hypertension and Differential Diagnosis from Liver Cirrhosis

Idiopathic portal hypertension (IPH) mimics liver cirrhosis in many aspects, and no efficient imaging method to differentiate the two diseases has been reported to date. In this study, the imaging and pathological characteristics were analysed for both IPH and cirrhosis. From January 2015 to March 2019, ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) images and pathological results from 16 IPH and 16 liver cirrhosis patients, as well as imaging results of 16 normal patients as a control group, were retrospectively reviewed. The age of the patients was 39 ± 20 years. There was a significant difference in the mean lumen diameter, wall thickness and ratio of thickness to diameter between the IPH and liver cirrhosis patients in the main and sagittal portal veins (P < 0.05), as well as in the lumen diameter and ratio of thickness to diameter between the IPH and liver cirrhosis patients in the Segment 3 (S3) portal vein (P < 0.05). In IPH patients, the main imaging changes were portal vein wall thickening, stenosis or occlusion, a low enhancement area along the portal vein in the delay phase in contrast-enhanced imaging, and a non-homogeneous change in T1WI. The corresponding pathological changes included interlobular vein thickening, stenosis, occlusion, portal area fibrosis, and atrophy or apoptosis of hepatocytes. The main imaging characteristic of liver cirrhosis was a nodular change in T1WI, and the related pathological change was pseudolobule formation. The imaging characteristics of IPH include thickening of the portal vein vascular wall, stenosis of the portal vein lumen and the absence of diffuse cirrhosis-like nodules. These imaging features have a definite pathological basis and could help make differential diagnoses between IPH and cirrhosis.

Japanese periodical nationwide epidemiologic survey of aberrant portal hemodynamics

AIM

Idiopathic portal hypertension (IPH), extrahepatic portal obstruction (EHO), and Budd-Chiari syndrome (BCS) are characterized by aberrant portal hemodynamics of unknown etiology. The aim of this study was to explore trends in the descriptive epidemiology of these diseases through periodical nationwide surveys.

METHODS

Nationwide epidemiologic surveys were undertaken in 1999, 2005, and 2015 using the same protocol. The survey targets were selected from all departments of gastrointestinal medicine, surgery, pediatrics, and pediatric surgery in Japan by stratified random sampling according to the number of beds. We asked each department to complete a mail-back questionnaire on the annual numbers of patients with IPH, EHO, and BCS during the preceding year.

RESULTS

The estimated number of BCS patients increased from 280 (95% confidence interval, 200-360) in 1999 survey to 410 (300-530) in 2015 survey, whereas the number of IPH and EHO patients has remained largely unchanged during the 15 years (IPH was approximately 1000; EHO was approximately 770 in 2015 survey). The mean age at symptom onset was approximately 45 years for IPH, 30 years for EHO, and 40 years for BCS over the past 15 years. Those who described disease aggravation from the time of diagnosis accounted for approximately 10% of IPH, 15% of EHO, and 20% of BCS patients in each of the three surveys.

CONCLUSIONS

In Japan, the prevalence of BCS is increasing, while those of IPH and EHO appear to be stable. Clinical characteristics, including prognoses, have remained largely unchanged in the past 15 years.

Natural history of patients with non cirrhotic portal hypertension: Comparison with patients with compensated cirrhosis

BACKGROUND

The knowledge of natural history of patients with portal hypertension (PH) not due to cirrhosis is less well known than that of cirrhotic patients.

AIM

To describe the clinical presentation and the outcomes of 89 patients with non-cirrhotic PH (25 with non-cirrhotic portal hypertension, INCPH, and 64 with chronic portal vein thrombosis, PVT) in comparison with 77 patients with Child A cirrhosis.

METHODS

The patients were submitted to a standardized clinical, laboratory, ultrasonographic and endoscopic follow-up. Variceal progression, incidence of variceal bleeding, portal vein thrombosis, ascites and survival were recorded.

RESULTS

At presentation, the prevalence of varices, variceal bleeding and ascites was similar in the 3 groups. During follow-up, the rate of progression to varices at risk of bleeding (p < 0.0001) and the incidence of first variceal bleeding (p = 0.02) were significantly higher in non-cirrhotic then in cirrhotic patients. A PVT developed in 32% of INCPH patients and in 18% of cirrhotics (p = 0.02).

CONCLUSIONS

In the patients with non-cirrhotic PH variceal progression is more rapid and bleeding more frequent than in cirrhotics. Patients with INCPH are particularly prompt to develop PVT. This observational study suggests that the management of patients with non-cirrhotic PH should take into consideration the natural history of portal hypertension in these patients and cannot be simply derived by the observation of cirrhotic patients.

Vascular liver diseases on the clinical side: definitions and diagnosis, new concepts

The components of the hepatic vascular system (hepatic arteries, portal and hepatic veins, sinusoids, and lymphatics) can be damaged by various types of injury. Each of the resulting conditions is rare, which has limited knowledge and awareness. In the last two decades, international collaborations have allowed to reach critical masses of data, which has driven significant progresses in understanding and management of vascular disorders of the liver. The present paper discusses definitions, denominations, and diagnosis of such vascular disorders with the exception of those affecting hepatic arteries. Evolving pathogenic or pathophysiologic views relevant to the clinical aspects are also overviewed.

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.

Liver transplantation in adults with portal vein thrombosis: Data from the China Liver Transplant Registry

OBJECTIVES

Portal vein thrombosis (PVT) is a common complication in patients with liver cirrhosis. During liver transplantation (LT), PVT may complicate the procedure and lead to a poor prognosis. The aim of this study is to evaluate patients enrolled in the China Liver Transplant Registry, to understand the influence of PVT to the LT recipients.

METHODS

We collected data from patients who underwent LT and were entered into the China Liver Transplant Registry. All data of medical records and follow-up were retrospectively reviewed. The preoperative condition, duration of surgery, intraoperative blood loss, postoperative early and late PVT, and survival rates were compared between patients with PVT and those without PVT. Multivariate Cox analysis and survival analysis were used to determine the influence of PVT.

RESULTS

A total of 20,524 cases were recruited into the study. In all, 1810 (8.82%) patients were diagnosed with preoperative PVT of various severities. All patients were followed up for an average of 30.25±33.25months (up to a maximum of 171.68months). Patients with PVT had a significantly longer operating time, more intraoperative blood loss and a higher rate of post-LT PVT (P<0.001). Multivariate Cox analysis showed that PVT did not reduce the recipients' survival rate (HR=0.89, 95% CI: 0.774-1.024, P=0.103). There was no significant difference in cumulative survival rate (P=0.059) between patients without PVT, and patients with PVT.

CONCLUSIONS

PVT increases the difficulty of LT, but doesn't reduce the survival rate. Therefore, PVT is not an absolute contraindication for LT in experienced transplantation centers.

Comprehensive Screening of Gene Function and Networks by DNA Microarray Analysis in Japanese Patients with Idiopathic Portal Hypertension

The functions of genes involved in idiopathic portal hypertension (IPH) remain unidentified. The present study was undertaken to identify the functions of genes expressed in blood samples from patients with IPH through comprehensive analysis of gene expression using DNA microarrays. The data were compared with data from healthy individuals to explore the functions of genes showing increased or decreased expression in patients with IPH. In cluster analysis, no dominant probe group was shown to differ between patients with IPH and healthy controls. In functional annotation analysis using the Database for Annotation Visualization and Integrated Discovery tool, clusters showing dysfunction in patients with IPH involved gene terms related to the immune system. Analysis using network-based pathways revealed decreased expression of adenosine deaminase, ectonucleoside triphosphate diphosphohydrolase 4, ATP-binding cassette, subfamily C, member 1, transforming growth factor-β, and prostaglandin E receptor 2; increased expression of cytochrome P450, family 4, subfamily F, polypeptide 3, and glutathione peroxidase 3; and abnormalities in the immune system, nucleic acid metabolism, arachidonic acid/leukotriene pathways, and biological processes. These results suggested that IPH involved compromised function of immunocompetent cells and that such dysfunction may be associated with abnormalities in nucleic acid metabolism and arachidonic acid/leukotriene-related synthesis/metabolism.

[Idiopathic non-cirrhotic portal hypertension: An update]

Idiopathic non-cirrhotic portal hypertension is an under-estimated cause of portal hypertension. The diagnosis requires the exclusion of cirrhosis, common causes of chronic liver disease and venous obstruction of the portal and hepatic veins. It has been associated with various extra-hepatic conditions that are most frequently immunologic, prothrombotic, hematologic and toxic. The most frequent clinical complications are variceal hemorrhage and portal vein thrombosis. Complications of portal hypertension should be managed as in patients with cirrhosis.

Idiopathic portal hypertension: natural history and long-term outcome

Idiopathic portal hypertension (IPH) is a rare cause of intrahepatic portal hypertension. Data on natural history and prognosis of IPH are limited. We sought to describe the complications and long-tem outcome of IPH by retrospectively studying 69 biopsy-proven cases of IPH. Mean duration of follow-up was 6.7 ± 4.6 years. All patients had evidence of portal hypertension (PH) at diagnosis, and 42% were symptomatic. Variceal bleeding (VB) was the most common manifestation. In those without bleeding at diagnosis, 74% had varices at first endoscopy. In those with large varices, the 1-year probability of first bleeding despite primary prophylaxis was 9%. The 1-year probability of rebleeding was 22%. Ascites and hepatic encephalopathy was documented in 26% and 7% of patients, respectively, at least once during the clinical course. The 1-year probability of developing portal vein thrombosis (PVT) was 9%, and 53% of patients receiving anticoagulation achieved recanalization. Human immunodeficiency virus (HIV) infection and VB at diagnosis were the independent predictors of PVT. Seven patients died (6 as a result of an IPH-related cause) and 2 were transplanted. Probability of liver transplantation-free survival was 82% at 10 years. Presence of a severe associated disorder and ascites as a presenting symptom were associated with poor survival.

CONCLUSION

Variceal bleeding is a major complication of IPH. Using, in IPH patients, the same management approach for PH as in cirrhosis is safe and maintains a low incidence of first bleeding and rebleeding in IPH patients. PVT is a frequent complication, particularly in those with HIV infection. Despite several complications, overall survival of patients with IPH is considerably good.

The current clinical aspects of idiopathic portal hypertension

IDIOPATHIC PORTAL HYPERTENSION (IPH) COMPRISES DISORDERS DEVELOPING INCREASED PORTAL PRESSURE IN THE ABSENCE OF CIRRHOSIS: the clear mechanisms to explain this disease are still not well recognized. IPH usually suggests a benign prognosis, but sometimes is complicated with severe hemorrhage due to ruptured esophageal varices, or massive splenomegaly. Conventional treatments for those complications for patients with cirrhosis usually works when diverted to patients with IPH, although some of those patients might require liver transplantation if the treatment fails. However, there are few consistent treatment strategies for IPH itself, its complications or the indications for liver transplantation. In this mini review, we summarize the clinical manifestations and several potential theories to explain the etiology, as well as the current treatment options for IPH.

Implications of portal vein thrombosis after splenectomy for patients with idiopathic portal hypertension

PURPOSE

Idiopathic portal hypertension (IPH) is considered to be closely related to portal vein thrombosis (PVT). The aim of this study was to clarify the incidence, clinical characteristics, and outcomes of PVT in patients with IPH after splenectomy.

METHODS

We investigated the rates, clinical characteristics, and outcomes of PVT in 18 patients who underwent splenectomy for IPH, during a mean follow-up period of 152 ± 83 months.

RESULTS

Seven of the 18 patients (39%) experienced gastrointestinal bleeding, which was from the varices in 4. Eight patients (44%) had PVT, and the mean interval until its detection after splenectomy was 22 ± 41 months. The cumulative gastrointestinal bleeding rates 5, 10, and 15 years after surgery were 24%, 31%, and 41%, respectively. The cumulative survival rates 5, 10, and 15 years after surgery were 94%, 74%, and 65%, respectively. There were no significant differences in the cumulative gastrointestinal bleeding and survival rates between patients with and those without PVT.

CONCLUSION

Despite the high incidence of PVT in IPH patients postsplenectomy, it may not be related to their gastrointestinal bleeding or prognosis.

Idiopathic noncirrhotic portal hypertension

Idiopathic noncirrhotic portal hypertension (INCPH) is characterized by an increased portal venous pressure gradient in the absence of a known cause of liver disease and portal vein thrombosis. In contrast to the high prevalence of this disorder in India, INCPH is a rare disease in the Western world. The etiology of INCPH can be divided in five categories: chronic infections, exposure to medication or toxins, thrombophilia, immunological disorders, and genetic disorders. Multifactorial etiology can also be encountered. Chronic abdominal infection is incriminated as the most important etiological factor in Eastern patients and thrombophilia in Western patients. The majority of patients with INCPH initially present with signs or complications of portal hypertension (mainly variceal bleeding and splenomegaly). These patients usually have preserved liver function. Liver function impairment occurs mainly in the context of intercurrent conditions. Patients with INCPH are often clinically and radiologically misdiagnosed as liver cirrhosis, so that a liver biopsy is indispensable to discriminate cirrhosis from INCPH. Histopathological characteristics of INCPH are heterogeneous, demonstrating overlap between several pathological entities (e.g., hepatoportal sclerosis, nodular regenerative hyperplasia, and incomplete septal cirrhosis). Even though hemodynamical changes in INCPH patients are not comparable to those in cirrhotics, prophylaxis and treatment of variceal bleeding are recommended to be similar. Anticoagulation therapy must be considered only in patients who develop portal vein thrombosis. INCPH has been considered a disorder with a relatively benign disease course. However, liver failure, hepatic encephalopathy, and hepatopulmonary syndrome can occur and are considered indications for liver transplantation.

Noncirrhotic portal hypertension

Portal hypertension is characterized by an increase in portal pressure (> 10 mmHg) and could be a result of cirrhosis of the liver or of noncirrhotic diseases. When portal hypertension occurs in the absence of liver cirrhosis, noncirrhotic portal hypertension (NCPH) must be considered. The prognosis of this disease is much better than that of cirrhosis. Noncirrhotic diseases are the common cause of portal hypertension in developing countries, especially in Asia. NCPH is a heterogeneous group of diseases that is due to intrahepatic or extrahepatic etiologies. In general, the lesions in NCPH are vascular in nature and can be classified based on the site of resistance to blood flow. In most cases, these disorders can be explained by endothelial cell lesions, intimal thickening, thrombotic obliterations, or scarring of the intrahepatic portal or hepatic venous circulation. Many different conditions can determine NCPH through the association of these various lesions in various degrees. Many clinical manifestations of NCPH result from the secondary effects of portal hypertension. Patients with NCPH present with upper gastrointestinal bleeding, splenomegaly, ascites after gastrointestinal bleeding, features of hypersplenism, growth retardation, and jaundice due to portal hypertensive biliopathy. Other sequelae include hyperdynamic circulation, pulmonary complications, and other effects of portosystemic collateral circulation like portosystemic encephalopathy. At present, pharmacologic and endoscopic treatments are the treatments of choice for portal hypertension. The therapy of all disorders causing NCPH involves the reduction of portal pressure by pharmacotherapy or portosystemic shunting, apart from prevention and treatment of complications of portal hypertension.

[Deficiencies in proteins C and S in a patient with idiopathic portal hypertension accompanied by portal vein thrombosis]

Portal vein thrombosis (PVT) is an uncommon cause of presinusoidal portal hypertension. Among various hepatoportal disorders, noncirrhotic portal hypertension conditions such as idiopathic portal hypertension (IPH) are considered to have a close relation with PVT. PVT is known to have several predisposing conditions, including infection, malignancies, and coagulation disorders. There is growing interest and recognition that deficiencies in proteins C and S are associated with a hypercoagulable state. These deficiencies are regarded as key factors of systemic hypercoagulability and recurrent venous thromboembolism. We report the case of a 19-year-old male diagnosed as IPH with PVT and combined deficiencies in proteins C and S.

Idiopathic portal hypertension in patients with HIV infection treated with highly active antiretroviral therapy

OBJECTIVES

Idiopathic portal hypertension (IPH) is the presence of PH in the absence of liver disease. Recently, IPH was reported in HIV patients on highly active antiretroviral therapy (HAART). We describe for the first time the hepatic and systemic hemodynamic profile, liver stiffness, and histological features of eight patients with HIV-related IPH.

METHODS

HIV-positive patients were identified from our IPH database over 3 years.

RESULTS

Five patients presented with variceal bleeding, two with splenomegaly, and one with ascites. All had large esophageal varices. Median hepatic venous pressure gradient (HVPG) was 8 mm Hg (range 3.5-14.5), clearly underestimating the true portal pressure. This is probably because of a presinusoidal component of PH and because of the presence of intrahepatic venous collaterals. Median liver stiffness was 8.9 kPa (range 6.8-14.9) and was unreliable in predicting the presence of fibrosis or of esophageal varices. The main histological features were absence of portal vein radicles and areas of regenerating hepatocytes. Six patients (75%) developed portal vein thrombosis during a 2-year follow-up.

CONCLUSIONS

There is a subset of HIV patients without cirrhosis but with PH compatible with IPH. In these patients, the hepatic and systemic hemodynamic profile is similar to other forms of IPH. The histological profile reflects an underlying vascular disorder affecting the medium-sized portal vein branches. Development of portal vein thrombosis is a frequent complication and requires close monitoring.

Effect of signal intensity from the accumulated microbubbles in the liver for differentiation of idiopathic portal hypertension from liver cirrhosis

PURPOSE

To examine the possibility of using contrast material-enhanced ultrasonography (US) to differentiate idiopathic portal hypertension (IPH) from cirrhosis.

MATERIALS AND METHODS

This was an institutional review board-approved prospective study with written informed consent. The study consisted of 23 patients (mean age, 60 years +/- 11; range, 37-85 years) with biopsy-proved cirrhosis, 10 patients (mean age, 65 years +/- 8; range, 51-78 years) with IPH, and 27 control subjects (mean age, 46 years +/- 17; range, 26-82 years) without any focal hepatic lesions or portal vein thrombosis. The patients underwent contrast-enhanced US for the observation of the right liver lobe. The time of the onset of contrast enhancement in the right hepatic artery and right portal vein was examined at vascular phase under continuous low-power emission, and signal intensity differences (in decibels) by using instantaneous high-power emission in the liver parenchyma were analyzed at late phase (15 minutes). Interobserver variability was quantified as coefficients of variation.

RESULTS

Onset time of contrast enhancement in the right portal vein was significantly longer for both IPH (22 sec +/- 3.9, P = .0035) and cirrhosis (19.3 sec +/- 4.7, P = .04) patients than for control subjects (17 sec +/- 3.3), with no significant difference in the onset time in the right hepatic artery. Images obtained in both IPH patients (21.2 dB +/- 1.4) and control subjects (22.1 dB +/- 2.2) had significantly higher signal intensity differences than those obtained in cirrhosis patients (13.8 dB +/- 2.8, P < .0001), with no significant difference between images of IPH patients and control subjects. Signal intensity differences of more than 18 dB had 100% sensitivity and specificity for the diagnosis in IPH patients and control subjects. Interobserver variability for signal intensity differences was 8.7%.

CONCLUSION

Contrast-enhanced US may offer the possibility for a simple, easy, and noninvasive diagnosis of IPH.

Noncirrhotic portal fibrosis/idiopathic portal hypertension: APASL recommendations for diagnosis and treatment

The Asian Pacific Association for the Study of the Liver (APASL) Working Party on Portal Hypertension has developed consensus guidelines on the disease profile, diagnosis, and management of noncirrhotic portal fibrosis and idiopathic portal hypertension. The consensus statements, prepared and deliberated at length by the experts in this field, were presented at the annual meeting of the APASL at Kyoto in March 2007. This article includes the statements approved by the APASL along with brief backgrounds of various aspects of the disease.

Clinical characteristics of idiopathic portal hypertension

Idiopathic portal hypertension is one of the interesting causes of portal hypertension. Even in very developed medical centers, this disorder is still one of the most important misdiagnoses of clinical practice. To inexperienced physicians, presenting esophageal varices and upper gastrointestinal bleeding usually prompt an unfortunate diagnosis of cirrhosis. A heterogenous clinical presentation and progression of this disorder should be recognized by physicians, and management should be directed towards some specific problems confined to this disorder. Although a genetic basis and other factors are implicated in its pathogenesis, exact underlying mechanism(s) is (are) unknown. In this review, we discuss the heterogeneity of idiopathic portal hypertension, its etiopathogenesis, clinical presentation and management issues. With the expectation of an excellent prognosis, a practicing gastroenterologist should be aware that “not all varices mean cirrhosis”.