Liver Transplantation for Porto-sinusoidal Vascular Liver Disorder: Long-term Outcome

Noncirrhotic portal hypertension: current trends and future directions

PURPOSE OF REVIEW

Noncirrhotic portal hypertension (NCPH) comprises a diverse group of vascular liver disorders characterized by elevated portal pressure without cirrhosis. Due to overlapping clinical features, distinguishing NCPH from cirrhosis and porto-sinusoidal vascular disorder (PSVD) remains challenging. This review explores recent advancements in diagnosis, differentiation, and evolving treatment strategies.

RECENT FINDINGS

NCPH is characterized by preserved liver function and near-normal hepatic venous pressure gradients (HVPG). It shares risk factors with PSVD, including infections, drugs, toxins, and prothrombotic conditions. Diagnostic advancements, such as liver stiffness measurement (LSM) and splenic stiffness measurement (SSM), offer noninvasive differentiation from cirrhosis, while liver biopsy remains crucial for confirming PSVD and noncirrhotic portal fibrosis (NCPF). Imaging is reliable for diagnosing extrahepatic portal vein obstruction (EHPVO). Transjugular intrahepatic portosystemic shunts (TIPS) for refractory variceal bleeding or ascites, achieving rebleeding control in 72-80% of cases. Surgical shunts and splenectomy remain essential for uncontrolled bleeding and portal biliopathy, demonstrating excellent variceal control (93-95%).

SUMMARY

NCPH requires a high index of suspicion for diagnosis. Differentiation from cirrhosis and PSVD relies on clinical, histological, and hemodynamic assessments. Management focuses on endoscopic, interventional, and surgical strategies tailored to disease severity. Future research should standardize diagnostic criteria, explore targeted therapies, and refine prognostic tools to improve outcomes.

Prognostic Role of Endoscopic Ultrasound Guided Direct Portal Pressure Gradient Measurement in Porto-Sinusoidal Vascular Disorder

BACKGROUND & AIMS

HVPG is the gold standard for the diagnosis of clinically significant portal hypertension (CSPH), a condition associated with the risk of developing hepatic decompensation events. However, HVPG is an indirect method to measure portal pressure, and its application in the pre-sinusoidal form of portal hypertension (PH), as in porto-sinusoidal vascular disorder (PSVD), is hindered by low accuracy. Recently, endoscopic ultrasound-guided portal pressure gradient (EUS-PPG) measurement, which allows direct measurement of portal pressure, is emerging as a safe method and may overcome the limitation of HVPG. However, data in patients with CSPH and the pre-sinusoidal form of PH are still missing. This study aims to evaluate the safety and usefulness of EUS-PPG compared to HVPG in a cohort of patients with PSVD and CSPH.

METHODS

In this prospective single center study, patients with a diagnosis of PSVD who presented a clinical suspicion of CSPH underwent HVPG and EUS-PPG baseline measurements. A second EUS-PPG measurement was performed in patients naïve to non-selective beta-blockers (NSBBs) to evaluate haemodynamic response to therapy.

RESULTS

Twenty-six patients were enrolled and a total of 26 HVPG and 35 EUS-PPG measurements were performed, without any adverse events. Mean EUS-PPG was significantly higher than mean HVPG value (16.7 ± 5.5 mmHg versus 5.5 ± 2.8 mmHg). At logistic multivariate regression analysis, EUS-PPG value was the only variable associated with hepatic decompensation.

CONCLUSIONS

EUS-PPG measurement is safe and might have a prognostic role in patients with PSVD and CSPH, outperforming HVPG.

TRIAL REGISTRATION

ID5486.

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.

Porto-sinusoidal vascular liver disorder with portal hypertension: Natural history and long-term outcome

BACKGROUND & AIMS

Current knowledge of the natural history of patients with porto-sinusoidal vascular disorder (PSVD) is derived from small studies. The aim of the present study was to determine the natural history of PSVD and prognostic factors in a large multicenter cohort of patients.

METHODS

We performed a retrospective study on patients with PSVD and signs of portal hypertension (PH) prospectively registered in 27 centers.

RESULTS

A total of 587 patients were included, median age of 47 years and 38% were women. Four-hundred and one patients had an associated condition, which was graded as severe in 157. Median follow-up was 68 months. At diagnosis, 64% of patients were asymptomatic while 36% had a PH-related complication: PH-related bleeding in 112 patients, ascites in 117, and hepatic encephalopathy in 11. In those not presenting with bleeding, the incidence of first bleeding was 15% at 5 years, with a 5-year rebleeding rate of 18%. The 5-year cumulative incidence of new or worsening ascites was 18% and of developing portal vein thrombosis was 16%. Fifty (8.5%) patients received a liver transplantation and 109 (19%) died, including 55 non-liver-related deaths. Transplant-free survival was 97% and 83% at 1 and 5 years, respectively. Variables independently associated with transplant-free survival were age, ascites, serum bilirubin, albumin and creatinine levels at diagnosis and severe associated conditions. This allowed for the creation of a nomogram that accurately predicted prognosis.

CONCLUSIONS

The prognosis of PSVD is strongly determined by the severity of the associated underlying conditions and parameters of liver and renal function.

IMPACT AND IMPLICATIONS

Porto-sinusoidal vascular liver disorder (PSVD) is a rare entity that usually affects young people, frequently causes severe complications of portal hypertension, and may reduce life expectancy. To date, there is scarce information regarding its clinical manifestations, natural history and prognostic factors. The present study, including the largest number of patients with PSVD reported so far, shows that overall, when managed at centers of expertise, the prognosis of patients with PSVD is good, with LT-free survival rates of 83% and 72% at 5 and 10 years, respectively. Presence and severity of an underlying associated condition, presence of ascites, age and bilirubin, albumin and creatinine levels were associated with poor prognosis. These results are important to know for hepatologists. A final model combining these parameters enabled development of a nomogram that predicts prognosis with good discrimination and calibration capacity and can be easily applied in clinical practice.

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.

Metabolomic profiles differentiate between porto-sinusoidal vascular disorder, cirrhosis, and healthy individuals

Background & Aims

Porto-sinusoidal vascular disorder (PSVD) is a rare and diagnostically challenging vascular liver disease. This study aimed to identify distinct metabolomic signatures in patients with PSVD or cirrhosis to facilitate non-invasive diagnosis and elucidate perturbed metabolic pathways.

Methods

Serum samples from 20 healthy volunteers (HVs), 20 patients with histologically confirmed PSVD or 20 patients with cirrhosis were analyzed. Metabolites were measured using liquid chromatography-mass spectrometry. Differential abundance was evaluated with Limma's moderated t-statistics. Artificial neural network and support vector machine models were developed to classify PSVD against cirrhosis or HV metabolomic profiles. An independent cohort was used for validation.

Results

A total of 283 metabolites were included for downstream analysis. Clustering effectively separated PSVD from HV metabolomes, although a subset of patients with PSVD (n = 5, 25%) overlapped with those with cirrhosis. Differential testing revealed significant PSVD-linked metabolic perturbations, including pertubations in taurocholic and adipic acids, distinguishing patients with PSVD from both HVs and those with cirrhosis. Alterations in pyrimidine, glycine, serine, and threonine pathways were exclusively associated with PSVD. Machine learning models utilizing selected metabolic signatures reliably differentiated the PSVD group from HVs or patients with cirrhosis using only 4 to 6 metabolites. Validation in an independent cohort demonstrated the high discriminative ability of taurocholic acid (AUROC 0.899) for patients with PSVD vs. HVs and the taurocholic acid/aspartic acid ratio (AUROC 0.720) for PSVD vs. cirrhosis.

Conclusions

High-throughput metabolomics enabled the identification of distinct metabolic profiles that differentiate between PSVD, cirrhosis, and healthy individuals. Unique alterations in the glycine, serine, and threonine pathways suggest their potential involvement in PSVD pathogenesis.

Impact and implications

Porto-sinusoidal vascular disorder (PSVD) is a vascular liver disease that can lead to pre-sinusoidal portal hypertension in the absence of cirrhosis, with poorly understood pathophysiology and no established treatment. Our study demonstrates that analyzing the serum metabolome could reveal distinct metabolic signatures in patients with PSVD, including alterations in the pyrimidine, glycine, serine and threonine pathways, potentially shedding light on the disease's underlying pathways. These findings could enable earlier and non-invasive diagnosis of PSVD, potentially reducing reliance on invasive procedures like liver biopsy and guiding diagnostic pathways.

Porto-sinusoidal Vascular Disease: Classification and Clinical Relevance

Non-cirrhotic portal hypertension (NCPH) is a well-recognized clinico-pathological entity, which is associated with clinical signs and symptoms, imaging, and endoscopic features of portal hypertension (PHT), in absence of cirrhosis. In patients with NCPH without known risk factors of PHT or extrahepatic portal vein thrombosis, the condition is called idiopathic non-cirrhotic portal hypertension (INCPH). There are multiple infectious, immune related causes, systemic diseases, drug and toxin exposures, haematological disorders, and metabolic risk factors that have been associated with this INCPH. However, the causal pathogenesis is still unclear. The Vascular liver disorders interest group group recently proposed porto-sinusoidal vascular disease (PSVD) as a syndromic entity, which provides definite histopathological criteria for diagnosis of NCPH (table 1). The three classical histo-morphological lesions specific for PSVD include obliterative portal venopathy, nodular regenerative hyperplasia, and incomplete septal fibrosis. The PSVD definition includes patients with portal vein thrombosis, PVT, and even those without PHT, thus broadening the scope of diagnosis to include patients who may have presented early, prior to haemodynamic changes consistent with PHT. However, this new diagnosis has pros and cons. The cons include mandating invasive liver biopsy to assess the PSVD histological triad in all patients with NCPH, an erstwhile clinical diagnosis in Asian patients. In addition, the natural history of the subclinical forms of PSVD without PHT and linear progression to develop PHT is unknown yet. In this review, we discuss the diagnosis and treatment of INCPH/PSVD, fallacies and strengths of the old and new schema, pathobiology of this disease, and clinical correlates in an Asian context. Although formulation of standardised diagnostic criteria is useful for comparison of clinical cohorts with INCPH/PSVD, prospective clinical validation in global cohorts is necessary to avoid misclassification of vascular disorders of the liver.

The autoimmune landscape of Porto-sinusoidal vascular disorder: What the rheumatologist needs to know

Porto-sinusoidal vascular disorder (PSVD) encompasses a group of vascular disorders characterized by lesions of the portal venules and sinusoids with clinical manifestations ranging from non-specific abnormalities in serum liver enzymes to clinically overt portal hypertension and related complications. Several reports have documented cases of PSVD in patients with systemic autoimmune conditions, such as systemic lupus erythematosus, systemic sclerosis, and rheumatoid arthritis. It is of note that these diseases share specific pathophysiological features with PSVD, including endothelial dysfunction, vascular inflammation, and molecular signatures. This narrative review aims to summarize the current knowledge on the association between PSVD and systemic autoimmune diseases, emphasizing the importance of promptly recognizing this condition in the rheumatological practice, and highlighting the key aspects where further research is necessary from both pathogenic and clinical perspectives.

[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.

Application of ultrasonography-elastography score to suspect porto-sinusoidal vascular disease in patients with portal vein thrombosis

BACKGROUND

Porto-sinusoidal vascular disease (PSVD) and portal vein thrombosis (PVT) are causes of portal hypertension characterized respectively by an intrahepatic and a pre-hepatic obstacle to the flow in the portal system. As PVT may be a consequence of PSVD, in PVT patients at presentation, a pre-existing PSVD should be suspected. In these patients the identification of an underlying PSVD would have relevant implication regarding follow-up and therapeutic management, but it could be challenging. In this setting ultrasonography may be valuable in differential diagnosis. The aim of the study was to use ultrasonography to identify parameters to discriminate between PSVD and "pure" PVT and then to suspect PVT secondary to a pre-existing PSVD.

METHODS

Fifty-three patients with histologically proven PSVD and forty-eight patients affected by chronic PVT were enrolled and submitted to abdominal ultrasonography with elastography by acoustic radiation force impulse (ARFI).

RESULTS

ARFI was higher and superior mesenteric vein (SMV) diameter was wider in PSVD patients than in PVT patients. Thus, a prognostic score was obtained as linear combinations of the two parameters with a good discrimination capacity between PSVD and PVT (the area under the curve = 0.780; 95% confidence interval: 0.690-0.869).

CONCLUSIONS

A score based on ARFI and SMV diameter may be useful to suspect an underlying PSVD in patients with PVT and to identify a subgroup of patients to be submitted to liver biopsy.

Management of liver disease and portal hypertension in common variable immunodeficiency (CVID)

Patients with common variable immunodeficiency (CVID) frequently develop liver disease and associated complications, which represent an increasingly prevalent unmet medical need. The main hepatic manifestation of CVID is nodular regenerative hyperplasia (NRH), resulting in non-cirrhotic portal hypertension (NCPH). Liver disease is often underdiagnosed, leading to poor outcomes and decreased survival. The increasing numbers of patients with CVID who are diagnosed late with progressive liver disease underscores the importance of appropriate clinical management and treatment of liver complications. At the same time, specific guidelines for the clinical management of CVID-related liver disease are still lacking. Here, we review the epidemiology of CVID-related liver disease, reveal new insights into NRH and NCPH biology and highlight recently uncovered opportunities for NCPH diagnostics in CVID. Finally, we focus on current management of liver disease, portal hypertension and its complications - the key challenge in patients with CVID. Specifically, we review recent data regarding the role of transjugular intrahepatic portosystemic shunt and liver transplantation in clinical management. The role for anticoagulants and immunosuppressants targeting the pathogenesis of NRH will also be discussed. We propose an updated algorithm for the diagnostic work-up and treatment of NCPH in CVID. Finally, we consider future needs and therapeutic opportunities for CVID-related liver disease.

Evidence for Alloimmune Sinusoidal Injury in De Novo Nodular Regenerative Hyperplasia After Liver Transplantation

Posttransplant nodular regenerative hyperplasia (NRH) mostly remains unexplained. Microvascular injury due to antibody-mediated rejection (AMR) is suspected, but lack of donor specific antibody (DSA) testing makes it difficult to prove. Centered around a 1-year period of routine DSA testing, concomitant protocol, and indicated posttransplant liver biopsies (LB), recipients with NRH (n = 18) were compared with a matched control group (n = 36). All index, previous, and subsequent LB were reviewed. Both groups were similar in terms of demographics, timing of index LB, and DSA. In the index LB, the NRH group had higher sinusoidal C4d positivity (p = 0.029) and perisinusoidal fibrosis (p = 0.034), both independently associated with NRH (p = 0.038 and 0.050, respectively). Features of "possible" chronic AMR were detected in 28.5% of the NRH group without a known cause and 0% of the control group (p = 0.009). The NRH group had more preceding indicated LB with increased incidence of rejection and biliary obstruction pattern. In the follow-up histology, overall, sinusoidal and portal C4d positivity, sinusoidal microvasculitis, and perisinusoidal fibrosis were also higher (all p < 0.050). In conclusion, we provide evidence towards the hypothesis that some cases of posttransplant NRH are related to preceding active and persistent AMR. Large multicenter studies with protocol DSA testing are required to confirm.