Methylenetetrahydrofolate reductase C677T gene mutation and hyperhomocysteinemia in Budd-Chiari syndrome and portal vein thrombosis: A systematic review and meta-analysis of observational studies

Homozygous MTHFR C677T carriers develop idiopathic portal vein thrombosis 20 years earlier than wild type

The aim of this study was to evaluate the impact of methylene tetrahydrofolate reductase (MTHFR) rs1801133 (C→T667 transition) on age at first idiopathic portal vein thrombosis (PVT) and to identify clinical and/or laboratory variables influencing age at first PVT, including plasma homocysteine and the prothrombin rs1799963 PT (G→A transition at position 20210) (PT) mutation. A retrospective cross-sectional cohort, including 15 MTHFR TT, 32 MTHFR TC and 22 MTHFR CC idiopathic PVT participants contributing demographics, age at PVT, plasma concentrations of homocysteine and of natural anticoagulants. MTHFR TT carriers presented with a lower age at PVT than heterozygous or wild-type genotypes (31 ± 8 vs. 48 ± 15 vs. 52 ± 13 years, P  = 0.001) and were more likely to have a plasma HC concentration above the cut-off (73.3 vs. 32 vs. 50%, P  = 0.04). MTHFR TT and protein C predicted age at PVT ( P  < 0.0001 and P  = 0.06); MTHFR TT predicted plasma homocysteine ( P  = 0.05). In the MTHFR TT group, plasma homocysteine inversely related to protein C ( P  = 0.03). Plasma homocysteine predicted the extent of PVT ( P  = 0.03). Compound MTHFR TT + PT GA did not lower age at first PVT compared to MTHFR TT alone (35 ± 9 vs. 30 ± 8 years). MTHFR TT is associated with a 20-year earlier PVT presentation than heterozygous and wild-type MTHFR genotypes. The inverse relation between plasma homocysteine and protein C contributes to the prematurity of PVT in the MTHFR TT group, whereas plasma homocysteine contributes to the extent of PVT. The recent exclusion of MTHFR genotyping from the thrombophilia screen needs revisiting in this setting.

Prothrombotic states in portal vein thrombosis and Budd-Chiari syndrome in India: A systematic review and meta-analysis

BACKGROUND

Both Budd-Chiari syndrome (BCS) and portal vein thrombosis (PVT) have been linked to various prothrombotic (PT) conditions. The PT profile in Asians is different from the west and there are no nationwide epidemiological surveys from India. Hence, the present meta-analysis was aimed at analyzing the prevalence of acquired and hereditary thrombophilia among Indian patients with non-cirrhotic PVT and BCS.

METHODS

A comprehensive literature search of Embase, Medline and Scopus was conducted from January 2000 to February 2022 for studies evaluating the prevalence of various PT conditions in Indian patients with PVT and BCS. Pooled prevalence rates across studies were expressed with summative statistics.

RESULTS

Thirty-five studies with 1005 PVT patients and 1391 BCS patients were included in the meta-analysis. At least one PT condition was seen in 46.2% (28.7-63.7) of the PVT patients and 44.9% (37.3-60.7) of the BCS patients. Multiple PT conditions were seen in 13.0% (4.2-21.8) of the PVT patients and 7.9% (3.5-12.4) of the BCS patients. Among PVT patients, hyperhomocysteinemia was the commonest prothrombotic condition (21.6%) followed by protein C (PC) deficiency (10.7%), Janus kinase 2 (JAK-2) mutation (8.5%) and antiphospholipid antibodies (APLA) (7.5%). Among patients with BCS, PC deficiency was the commonest prothrombotic condition (10.6%) followed by methylenetetrahydrofolate reductase (MTHFR) mutation (9.8%), APLA (9.7%) and JAK-2 mutation (9.1%).

CONCLUSION

The PT profile in Indian patients with abdominal vein thrombosis is different from that of the western data with a lower prevalence of PT conditions in patients with BCS.

Management of splanchnic vein thrombosis

The expression splanchnic vein thrombosis encompasses Budd-Chiari syndrome and portal vein thrombosis. These disorders have common characteristics: they are both rare diseases which can cause portal hypertension and its complications. Budd-Chiari syndrome and portal vein thrombosis in the absence of underlying liver disease share many risk factors, among which myeloproliferative neoplasms represent the most common; a rapid comprehensive work-up for risk factors of thrombosis is needed in these patients. Long-term anticoagulation is indicated in most patients. Portal vein thrombosis can also develop in patients with cirrhosis and in those with porto-sinusoidal vascular liver disease. The presence and nature of underlying liver disease impacts the management of portal vein thrombosis. Indications for anticoagulation in patients with cirrhosis are growing, while transjugular intrahepatic portosystemic shunt is now a second-line option. Due to the rarity of these diseases, studies yielding high-grade evidence are scarce. However, collaborative studies have provided new insight into the management of these patients. This article focuses on the causes, diagnosis, and management of patients with Budd-Chiari syndrome, portal vein thrombosis without underlying liver disease, or cirrhosis with non-malignant portal vein thrombosis.

Liver Cirrhosis Patients Homozygous for MTHFR C677T Develop Portal Vein Thrombosis 8 Years Earlier Than Wild Type

BACKGROUND AND AIM

Age at portal vein thrombosis (PVT) in liver cirrhosis (LC) carriers of the methylene tetrahydrofolate reductase (MTHFR) rs1801133 (C → T667 transition) polymorphism has never been addressed; we compared age at PVT in LC patients genotyped for the MTHFR and explored the interrelated clinical and laboratory factors predicting age at PVT.

APPROACH AND RESULTS

Retrospective cross-sectional cohort study. PVT participants: MTHFR CC n = 36, MTHFR CT n = 53, MTHFR TT n = 19; age, sex, age at PVT, Child-Pugh score, rs1799963 PT polymorphisms (G → A 20,210 transition), plasma HC and natural anticoagulants available for all participants. Age at PVT was lower in MTHFR TT than CT and CC (56 ± 13 vs. 57 ± 13 vs. 64 ± 9 years, p = 0.001); median (IQR) plasma HC was higher in MTHFR TT than in the other groups [(17 (9.4, 23.3) vs 13 (8,14.7) vs 11 (8.9, 12.7) μmol/l, p = 0.03)]. MTHFR TT, male gender and protein C predicted age at PVT (p = 0.02, p = 0.04 and p = 0.08); MTHFR TT and Child-Pugh score predicted plasma HC (p = 0.005 and p = 0.01) as well as low plasma protein C (p < 0.0001 and p = 0.0002). Plasma HC inversely related to protein C in the MTHFR TT group (p < 0.0001). Compound MTHFR TT with PT GA had lower age at PVT compared to MTHFR TT alone (49 ± 18 vs 58 ± 12 years).

CONCLUSIONS

MTHFR TT anticipates PVT associated with LC by an average of 8 years; MTHFR TT associates with severity of liver disease and to high plasma HC; the latter may contribute to the prematurity of PVT by interfering with the anticoagulant activity of protein C.

Portal Vein Thrombosis in a Patient With Methylenetetrahydrofolate Reductase Gene Mutation and Normal Homocysteine Levels

A 21-year-old male presented with chief complaints of abdominal pain, nausea, and vomiting and was found to have portal vein thrombosis (PVT) on computed tomography (CT) scan of the abdomen, which was redemonstrated on ultrasound. Thrombophilia workup was negative except that patient was heterozygous for methylenetetrahydrofolate reductase (MTHFR) gene mutation. Homocysteine levels were normal. The patient was started on enoxaparin and discharged on apixaban with the plan to continue anticoagulation for at least six months. Follow-up MRI after four months showed interval improvement of the main portal vein thrombus with the use of Eliquis.

No Association of Homocysteine, Anticardiolipin Antibody, and Anti-β2 Glycoprotein I Antibody With Portal Venous System Thrombosis in Liver Cirrhosis

Portal venous system thrombosis (PVST), a common complication of liver cirrhosis, is closely associated with thrombophilia. To explore the association of homocysteine (Hcy), anticardiolipin antibody (aCL), and anti-β2 glycoprotein I antibody (aβ₂GPI), which are possible thrombophilic factors, with PVST in liver cirrhosis. Overall, 654 non-malignant patients (219 with and 435 without liver cirrhosis) admitted between January 2016 and June 2020 were retrospectively evaluated. Presence of PVST, degree of main portal vein (MPV) thrombosis, and clinically significant PVST were identified. Hcy level, hyperhomocysteinemia (HHcy), aCL positivity, and aβ₂GPI positivity were compared according to the presence of liver cirrhosis and PVST. Positive aβ₂GPI was significantly more frequent in patients with liver cirrhosis than those without, but Hcy level and proportions of HHcy and positive aCL were not significantly different between them. PVST could be evaluated in 136 cirrhotic patients. Hcy level [10.57 μmol/L (2.71-56.82) versus 9.97 μmol/L (2.05-53.44); P = 0.796] and proportions of HHcy [4/44 (9.1%) versus 13/81 (16.0%); P = 0.413] and positive aCL [1/23 (4.3%) versus 10/52 (19.2%); P = 0.185] and aβ₂GPI [9/23 (39.1%) versus 21/52 (40.4%); P = 0.919] were not significantly different between cirrhotic patients with and without PVST. There was still no significant association of Hcy level, HHcy, aCL, or aβ₂GPI with PVST based on Child-Pugh classification, MPV thrombosis >50%, and clinically significant PVST. Hcy, aCL, and aβ₂GPI may not be associated with PVST in liver cirrhosis, suggesting that routine screening for Hcy, aCL, and aβ₂GPI should be unnecessary in such patients.

Budd-Chiari Syndrome: An Uncommon Cause of Chronic Liver Disease that Cannot Be Missed

Budd-Chiari syndrome (BCS), or hepatic venous outflow obstruction, is a rare cause of liver disease that should not be missed. Variable clinical presentation among patients with BCS necessitates a high index of suspicion to avoid missing this life-threatening diagnosis. BCS is characterized as primary or secondary, depending on etiology of venous obstruction. Most patients with primary BCS have several contributing risk factors leading to a prothrombotic state. A multidisciplinary stepwise approach is integral in treating BCS. Lifelong anticoagulation is recommended. Long-term monitoring of patients for development of cirrhosis, complications of portal hypertension, hepatocellular carcinoma, and progression of underlying diseases is important.

No Association between Ischemic Stroke and Portal Vein Thrombosis in Liver Cirrhosis

BACKGROUND AND AIMS

There seems to be a higher risk of ischemic stroke and portal vein thrombosis in liver cirrhosis. Both of them may be associated with hypercoagulability. We aim to explore the association between ischemic stroke and portal vein thrombosis in liver cirrhosis. Study Design and Methods. We selected patients from our prospectively established database of liver cirrhosis from December 2014 to July 2019. The difference between patients with and without stroke was compared. A 1 : 1 propensity score matching (PSM) analysis was performed to adjust the effect of age, sex, Child-Pugh score, and MELD score on our statistical results.

RESULTS

There were 349 cirrhotic patients in the cross-sectional study. The prevalence of stroke, ischemic stroke, hemorrhagic stroke, and portal vein thrombosis was 8.88% (31/349), 8.31% (29/349), 1.15% (4/349), and 28.65% (100/349) in liver cirrhosis, respectively. Patients with ischemic stroke were significantly older and had significantly higher proportions of alcohol abuse, smoking, and arterial hypertension and higher levels of white blood cell and low-density lipoprotein. However, statistical analyses with and without PSM did not find any significant association between ischemic stroke and portal vein thrombosis in patients with liver cirrhosis.

CONCLUSION

Ischemic stroke might not be associated with portal vein thrombosis in liver cirrhosis.

Review article: a multidisciplinary approach to the diagnosis and management of Budd-Chiari syndrome

BACKGROUND

Budd-Chiari syndrome (BCS) is a rare but fatal disease caused by obstruction in the hepatic venous outflow tract.

AIM

To provide an update of the pathophysiology, aetiology, diagnosis, management and follow-up of BCS.

METHODS

Analysis of recent literature by using Medline, PubMed and EMBASE databases.

RESULTS

Primary BCS is usually caused by thrombosis and is further classified into "classical BCS" type where obstruction occurs within the hepatic vein and "hepatic vena cava BCS" which involves thrombosis of the intra/suprahepatic portion of the inferior vena cava (IVC). BCS patients often have a combination of prothrombotic risk factors. Aetiology and presentation differ between Western and certain Asian countries. Myeloproliferative neoplasms are present in 35%-50% of European patients and are usually associated with the JAK2-V617F mutation. Clinical presentation is diverse and BCS should be excluded in any patient with acute or chronic liver disease. Non-invasive imaging (Doppler ultrasound, computed tomography, or magnetic resonance imaging) usually provides the diagnosis. Liver biopsy should be obtained if small vessel BCS is suspected. Stepwise management strategy includes anticoagulation, treatment of identified prothrombotic risk factors, percutaneous revascularisation and transjugular intrahepatic portosystemic stent shunt to re-establish hepatic venous drainage, and liver transplantation in unresponsive patients. This strategy provides a 5-year survival rate of nearly 90%. Long-term outcome is influenced by any underlying haematological condition and development of hepatocellular carcinoma.

CONCLUSIONS

With the advent of newer treatment strategies and improved understanding of BCS, outcomes in this rare disease have improved over the last three decades. An underlying haematological disorder can be the major determinant of outcome.

TIPSS for variceal bleeding in patients with idiopathic non-cirrhotic portal hypertension: comparison with patients who have cirrhosis

BACKGROUND

In patients with idiopathic non-cirrhotic portal hypertension (INCPH), the usual recommended strategy for management of variceal bleeding is the same as that in cirrhosis. However, this policy has been challenged by the different natural history between INCPH and cirrhosis.

AIM

To compare outcomes after transjugular intrahepatic portosystemic shunt (TIPSS) between INCPH and cirrhotic patients admitted for variceal bleeding.

METHODS

Between March 2001 and September 2015, 76 consecutive patients with biopsy-proven INCPH undergoing TIPSS for variceal bleeding in a tertiary-care centre were included. 76 patients with cirrhotic portal hypertension receiving TIPSS for variceal bleeding, and matched for age, sex, Child-Pugh class, stent type and index year of TIPSS creation served as controls.

RESULTS

Patients with INCPH, compared to those with cirrhosis, had significantly lower mortality (11% vs 36% at 5 years, adjusted HR, 0.37; 95% CI 0.15-0.87, P = 0.022), overt hepatic encephalopathy (16% vs 33% at 5 years, adjusted HR, 0.35; 95% CI 0.16-0.75, P = 0.007) and hepatic impairment, despite similar rates of further bleeding (33% vs 32% at 5 years, adjusted HR, 0.72; 95% CI 0.36-1.44, P = 0.358), and shunt dysfunction (35% vs 36% at 5 years, adjusted HR, 0.84; 95% CI 0.41-1.72, P = 0.627). These findings were consistent across different relevant subgroups.

CONCLUSIONS

Patients with INCPH treated with TIPSS for variceal bleeding had similar progression of portal hypertension (further bleeding and shunt dysfunction) but fewer complications of liver disease (overt hepatic encephalopathy and hepatic insufficiency) and lower mortality rate compared with cirrhotic patients with comparable liver function.

Covered TIPS versus endoscopic band ligation plus propranolol for the prevention of variceal rebleeding in cirrhotic patients with portal vein thrombosis: a randomised controlled trial

OBJECTIVE

Limited data are available on the prevention of variceal rebleeding in cirrhotic patients with portal vein thrombosis (PVT). This study aimed to compare transjugular intrahepatic portosystemic shunt (TIPS) with covered stents versus endoscopic band ligation (EBL) plus propranolol for the prevention of variceal rebleeding among patients with cirrhosis and PVT.

DESIGN

Consecutive cirrhotic patients (94% Child-Pugh class A or B) with PVT who had variceal bleeding in the past 6 weeks were randomly assigned to TIPS group (n=24) or EBL plus propranolol group (EBL+drug, n=25), respectively. Primary endpoint was variceal rebleeding. Secondary endpoints included survival, overt hepatic encephalopathy (OHE), portal vein recanalisation and rethrombosis, other complications of portal hypertension and adverse events.

RESULTS

During a median follow-up of 30 months in both groups, variceal rebleeding was significantly less frequent in the TIPS group (15% vs 45% at 1 year and 25% vs 50% at 2 years, respectively; HR=0.28, 95% CI 0.10 to 0.76, p=0.008), with a significantly higher portal vein recanalisation rate (95% vs 70%; p=0.03) and a relatively lower rethrombosis rate (5% vs 33%; p=0.06) compared with the EBL+drug group. There were no statistically significant differences in survival (67% vs 84%; p=0.152), OHE (25% vs 16%; p=0.440), other complications of portal hypertension and adverse events between groups.

CONCLUSION

Covered TIPS placement in patients with PVT and moderately decompensated cirrhosis was more effective than EBL combined with propranolol for the prevention of rebleeding, with a higher probability of PVT resolution without increasing the risk of OHE and adverse effects, but this benefit did not translate into improved survival.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT01326949.

Budd-Chiari syndrome/hepatic venous outflow tract obstruction

BACKGROUND

Budd-Chiari syndrome (BCS) is a rare disease characterized by hepatic venous outflow tract obstruction (HVOTO).

METHODS

Recent literature has been analyzed for this narrative review.

RESULTS

Primary BCS/HVOTO is a result of thrombosis. The same patient often has multiple risk factors for venous thrombosis and most have at least one. Presentation and etiology may differ between Western and certain Eastern countries. Myeloproliferative neoplasms are present in 40% of patients and are usually associated with the V617F-JAK2 mutation in myeloid cells, in particular peripheral blood granulocytes. Presentation and symptoms vary, thus this diagnosis must be considered in any patient with acute or chronic liver disease. Doppler ultrasound, computed tomography, or magnetic resonance imaging of the hepatic veins and inferior vena cava usually successfully provide noninvasive identification of the obstruction or its consequences in the collaterals of hepatic veins or the inferior vena cava. The reported life expectancy in these patients is 3 years after the first symptoms. The therapeutic strategy includes first, anticoagulation, correction of risk factors, diuretics, and prophylaxis for portal hypertension, then angioplasty for short-length venous stenosis followed by transjugular intrahepatic portosystemic shunt (TIPS) and finally liver transplantation. The progression of treatment is based on the response to therapy at each step. This strategy results in a 5-year survival rate of nearly 85%. The medium-term prognosis depends upon the severity of liver disease, and the long-term outcome can be jeopardized by transformation of underlying conditions and hepatocellular carcinoma.

CONCLUSION

BCS/HVOTO hepatic manifestations of BCS/HVOTO can be controlled in most patients with medical or radiological interventions. Underlying disease has become the major determinant of patient outcome.

Portal Vein Thrombosis: Recent Advance

Portal vein thrombosis is a life-threatening vascular disorder of the liver. In this chapter, I will review the recent advance regarding the epidemiology, etiology, management, and prognosis of portal vein thrombosis.

Review article: the aetiology of primary Budd-Chiari syndrome - differences between the West and China

BACKGROUND

China may have the largest number of Budd-Chiari syndrome (BCS) cases in the world (at least 1914 original papers were published, and at least 20 191 BCS patients were reported). Considering the discrepancy in the clinical profiles and preferred treatment selection of primary BCS between the West and China, understanding its aetiology in these two different regions is very important.

AIM

To review the data from large cohort studies and meta-analyses to illustrate the epidemiology of risk factors for BCS in the West and China.

METHODS

Relevant papers were identified by major English- and Chinese-language databases, conference abstracts, and by manual search.

RESULTS

Risk factors reviewed include myeloproliferative neoplasms (MPNs) and their related gene mutations, anti-phospholipid syndrome, paroxysmal nocturnal haemoglobinuria (PNH), hyperhomocysteinaemia and 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T mutation, factor V Leiden (FVL) and prothrombin G20210A mutations, inherited anti-thrombin, protein C and protein S deficiencies, pregnancy and puerperium, poverty, and family history.

CONCLUSIONS

We examined the differences in the aetiological distribution of BCS between the West and China. Several recommendations should be considered in Chinese BCS patients: (i) screening for hyperhomocysteinaemia and MTHFR mutation should be regularly performed; (ii) screening for MPNs, PNH, and anti-phospholipid syndrome should be selectively performed; (iii) inherited anti-thrombin, protein C, and protein S deficiencies should be actively explored; (iv) screening for FVL and prothrombin G20210A mutations may be unnecessary; and (v) the clinical significance of pregnancy and puerperium, poverty with bacterial infections and unsanitary environments, and family history as possible risk factors should never be neglected.

Role of Hyperhomocysteinemia and Methylene Tetrahydrofolate Reductase C677T Polymorphism in Idiopathic Portal Vein Thrombosis

Purpose:

Portal vein thrombosis (PVT) is a rare and life-threatening vascular disorder characterized by obstruction or narrowing of the portal vein. Hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been studied in PVT patients with conflicting results. In the present study the association of hyperhomocysteinemia and MTHFR C677T polymorphism with PVT risk was investigated in Iranians.

Materials and Methods:

Our study population consisted of 10 idiopathic PVT patients and 80 healthy control subjects matched for age and sex. MTHFR C677T polymorphism was genotyped by the polymerase chain reaction technique combined with restriction enzyme fragment length polymorphism (PCR-RFLP) technique and plasma total homocysteine (tHcy) levels were determined by enzyme immunoassay method.

Results:

Mean plasma tHcy levels were significantly higher in PVT patients (20.2±6.8) than control subjects (10.9±4.7) (P=0.001). Moreover, plasma tHcy levels were significantly higher in 677T allele carriers relative to 677C allele carriers in both PVT patients (P=0.01) and control subjects (P=0.03). Neither homozygote nor heterozygote genotypes of MTHFR C677T polymorphism correlated significantly with PVT risk (P>0.05). Moreover, MTHFR C677T polymorphism didn’t increase the risk of PVT under dominant (CT+TT vs. CC) or recessive (TT vs. CC+CT) genetic models analyzed (P>0.05). The difference in frequency of minor 677T allele between PVT patients and control subjects was not statistically significant (P>0.05).

Conclusion:

Based on the current study, we suggest that hyperhomocysteinemia constitutes a significant and common risk factor for PVT. Also, MTHFR C677T polymorphism is not a risk factor for PVT but is a contributing factor for elevated plasma tHcy levels.

Hyperhomocysteinemia and MTHFR C677T polymorphism in patients with portal vein thrombosis complicating liver cirrhosis

BACKGROUND

Portal vein thrombosis (PVT) is serious complication of liver cirrhosis (LC), especially in the presence of hepatocellular carcinoma (HCC). The liver plays a key role in homocysteine (Hcy) metabolism: mild hyperhomocysteinemia (HHcy) has been described in LC. HHcy is a risk factor for deep vein thrombosis. Methylen-tetrahydrofolate-reductase (MTHFR) C677T polymorphism is the commonest determinant of mild HHcy and has been involved also in cancer development.

AIM

To investigate a possible relation between HHcy, MTHFR status, HCC and PVT in patients affected by LC.

MATERIALS AND METHODS

100 patients affected by LC, 38 with (PVT group, 24 with HCC) and 62 without PVT (LC group, 14 with HCC) sex-, age-, liver disease stage and etiology-matched were assessed for thrombophilia, smoking status, plasma Hcy, MTHFRC677T polymorphism and homocysteine-related vitamin status.

RESULTS

A higher prevalence of HCC, HHcy and MTHFR TT status was observed in PVT group. No significant difference in vitamin status was observed between groups. Patients with HCC showed significantly higher plasma Hcy and higher prevalence of HHcy than patients without HCC. They had also higher prevalence of MTHFR TT status. In patients with TT status (n=11) and HCC, 10 had HHcy e 9 had PVT.

CONCLUSIONS

Mild HHcy is associated to LC may have a role in PVT development and assessment of plasma Hcy may be suggested in patients with LC (especially if complicated by HCC). Association between HCC and MTHFR TT status is intriguing, due the postulated role for this polymorphism in cancer: it may represent a possible link between HCC and PVT.

Nontumoral portal vein thrombosis in patients awaiting liver transplantation

Portal vein thrombosis (PVT) occurs in approximately 2%-26% of the patients awaiting liver transplantation (LT) and is no longer an absolute contraindication for LT. Nearly half of PVT cases are accidentally found during the LT procedure. The most important risk factor for PVT development in cirrhosis may be the severity of liver disease and reduced portal blood flow. Whether other inherited or acquired coagulation disorders also play a role is not yet clear. The development of PVT may have no effect on the liver disease progression, especially when it is nonocclusive. PVT may not increase the risk of wait-list mortality, but it is a risk factor for poor early post-LT mortality. Anticoagulation and transjugular intrahepatic portosystemic shunt (TIPS) are 2 major treatment strategies for patients with PVT on the waiting list. The complete recanalization rate after anticoagulation is approximately 40%. The role of TIPS to maintain PV patency for LT as the primary indication has been reported, but the safety and efficacy should be further evaluated. PVT extension and degree may determine the surgical technique to be used during LT. If a "conventional" end-to-end portal anastomotic technique is used, there is not a major impact on post-LT survival. Post-LT PVT can significantly reduce both graft and patient survival after LT and can preclude future options for re-LT.

Prevalence of Budd-Chiari Syndrome during Pregnancy or Puerperium: A Systematic Review and Meta-Analysis

Women during pregnancy or puerperium are likely to develop Budd-Chiari syndrome (BCS). However, the reported prevalence of pregnancy-related BCS varied considerably among studies. Our study aims to systematically review this issue. Overall, 817 papers were initially identified via the PubMed, EMBASE, China National Knowledge Infrastructure, and Chinese Scientific and Technological Journal databases. Twenty of them were eligible. The prevalence of pregnancy-related BCS varied from 0% to 21.5%. The pooled prevalence was 6.8% (95% CI: 3.9–10.5%) in all BCS patients, 6.3% (95% CI: 3.8–9.4%) in primary BCS patients, and 13.1% (95% CI: 7.1–20.7%) in female BCS patients. Among them, one study was carried out in Africa with a prevalence of 10.6%; 14 studies in Asian countries with a pooled prevalence of 7.1% (95% CI: 3.1–12.6%); and 5 studies in European countries with a pooled prevalence of 5.0% (95% CI: 3.1–7.3%). The pooled prevalence was 6.7% (95% CI: 2.6–12.3%) in studies published before 2005 and 7.3% (95% CI: 4.2–12.5%) in those published after 2005. In conclusion, pregnancy is a relatively common risk factor for BCS, but there is a huge variation in the prevalence among studies. Physicians should be aware of pregnancy-related BCS.

Role of D-dimer in the Development of Portal Vein Thrombosis in Liver Cirrhosis: A Meta-analysis

BACKGROUND AND AIMS

A meta-analysis was performed to explore the role of the D-dimer in the development of portal vein thrombosis (PVT) in liver cirrhosis.

METHODS

All papers were searched via PubMed, EMBASE, China National Knowledge Infrastructure, Wan Fang, and VIP databases. A standardized mean difference (SMD) with 95% confidence interval (CI) was pooled.

RESULTS

Overall, 284 studies were initially identified, of which 21 were included. Cirrhotic patients with PVT had a significantly higher D-dimer concentration than those without PVT (pooled SMD = 1.249, 95%CI = 0.740-1.758). After the portal hypertension-related surgery, cirrhotic patients with PVT had a similar preoperative D-dimer concentration to those without PVT (pooled SMD = 0.820, 95%CI = -0.122-0.286), but a higher postoperative value of D-dimer concentration than those without PVT (pooled SMD = 2.505, 95%CI = 0.975-4.036). Notably, the D-dimer concentration at the 1 st postoperative day was similar between cirrhotic patients with and without PVT (pooled SMD = 0.137, 95%CI = -0.827-1.101), but that at the 7 th post-operative day was higher in cirrhotic patients with PVT than in those without PVT (pooled SMD = 1.224, 95%CI = 0.277-2.171).

CONCLUSION

D-dimer might be regarded as a diagnostic marker for PVT in liver cirrhosis. In addition, postoperative D-dimer testing is worthwhile for the diagnosis of PVT after portal hypertension-related surgery.

Associations of antiphospholipid antibodies with splanchnic vein thrombosis: a systematic review with meta-analysis

Splanchnic vein thrombosis (SVT) refers to Budd-Chiari syndrome (BCS) and portal vein system thrombosis (PVST). Current practice guidelines have recommended the routine screening for antiphospholipid antibodies (APAs) in patients with SVT. A systematic review and meta-analysis of observational studies was performed to explore the association between APAs and SVT. The PubMed, EMBASE, and ScienceDirect databases were searched for all relevant papers, in which the prevalence of positive APAs or levels of APAs should be compared between BCS or noncirrhotic PVST patients versus healthy controls, or between cirrhotic patients with portal vein thrombosis (PVT) versus those without PVT. Fourteen studies were eligible. Only 1 study evaluated the role of APAs in BCS patients and found that positive immunoglobulin (Ig) G anticardiolipin antibody (aCL) was more frequently observed in BCS patients than in healthy controls; however, the associations of other APAs with BCS were not evaluated. Positive IgG aCL was more frequently observed in noncirrhotic patients with PVST than in healthy controls; however, other APAs, such as IgM aCL, lupus anticoagulants (LAs), anti-β2-glycoprotein-I antibody (aβ2GPI), and aβ2GPI-oxidized low-density lipoprotein antibody (ox-LDL) were not associated with noncirrhotic PVST. Positive unclassified aCL was more frequently observed in cirrhotic patients with PVT than in those without PVT; however, the association of IgG aCL and IgM aCL with the development of PVT in liver cirrhosis remained inconsistent among studies. The risk of BCS and noncirrhotic PVST might be increased by positive IgG aCL but not IgM aCL, LA, aβ2GPI, or aβ2GPI ox-LDL. However, the evidence regarding APAs in BCS originated from only 1 study. The association between APAs and PVT in liver cirrhosis was unclear.

Novel insights into the development of portal vein thrombosis in cirrhosis patients

The prognostic impact of portal vein thrombosis (PVT) in liver cirrhosis remains controversial among studies, primarily because the risk stratification of PVT is often lacking. A definition of clinically significant PVT should be proposed and actively improved. Moreover, the risk factors for the development of PVT in liver cirrhosis should be fully recognized to screen and identify high-risk patients. Currently, well-recognized risk factors include a reduced portal vein flow velocity, a worse liver function, splenectomy, liver transplantation, and factor V Leiden and prothrombin G20210A mutations. Novel risk factors include an increased flow volume of portosystemic collateral vessel, thrombopoietin receptor agnonists, and non-selective beta-blockers. In contrast to the traditional perspectives, the abnormalities of procoagulant and anticoagulant factors may not contribute to the development of PVT in liver cirrhosis. Further studies should explore the role of other risk factors, such as antiphospholipid antibodies, methylenetetrahydrofolate reductase C677T gene mutation, hyperhomocysteinemia, and myeloproliferative neoplasms.

Association between Portal Vein Thrombosis and Survival in Non-Liver-Transplant Patients with Liver Cirrhosis: A Systematic Review of the Literature

A systematic review of the literature was performed to analyze the association between portal vein thrombosis (PVT) and survival in non-liver-transplant patients with liver cirrhosis. PubMed, EMBASE, and Cochrane Library databases were searched for all relevant papers which evaluated the prognostic value of PVT in predicting the survival of liver cirrhosis. Meta-analyses were not conducted because the ways of data expression and lengths of follow-up were heterogeneous among studies. Overall, 13 papers were included. The 5-day, 6-week, and 1-year mortality were investigated in 1, 3, and 1 studies, respectively; and all of them were not significantly different between cirrhotic patient with and without PVT. By comparison, the 3-year mortality was reported in 1 study; and it was significantly increased by the presence of PVT. The overall mortality was analyzed in 5 studies; and the association with overall mortality and PVT was significant in 4 studies, but not in another one. However, as for the cirrhotic patients undergoing surgical or interventional shunts, the overall mortality was not significantly associated with the presence of PVT in 4 studies. In conclusion, the presence of PVT might be associated with the long-term mortality in non-liver-transplant patients with liver cirrhosis, but not with the short-term mortality.

Anticoagulation for the treatment of portal vein thrombosis in liver cirrhosis: a systematic review and meta-analysis of observational studies

BACKGROUND & AIMS

Systematic review and meta-analysis were performed to evaluate the safety and efficacy of anticoagulation for the treatment of portal vein thrombosis (PVT) in cirrhotic patients.

METHODS

The PubMed, EMBASE, Cochrane Library, and ScienceDirect databases were searched. The rates of bleeding complications and portal vein recanalization in patients who received anticoagulant therapy were pooled. The odds ratio (OR) with 95% confidence interval (CI) was calculated to express the difference in the rate of portal vein recanalization between anticoagulation and non-anticoagulation groups. All meta-analyses were conducted by using a random-effects model.

RESULTS

Sixteen of 960 initially identified papers were included. Two studies reported a low incidence of major anticoagulation-related complications (4% [2/55] and 3% [1/33]), but no lethal complications occurred. The rate of anticoagulation-related bleeding ranged from 0% to 18% with a pooled rate of 3.3% (95% CI=1.1%-6.7%). The heterogeneity was not significant in the meta-analysis. The total rate of portal vein recanalization ranged from 37% to 93% with a pooled rate of 66.6% (95% CI=54.7%-77.6%). The rate of complete portal vein recanalization ranged from 0% to 75% with a pooled rate of 41.5% (95% CI=29.2%-54.5%). However, the heterogeneity was significant in the 2 meta-analyses. The rate of complete portal vein recanalization was significantly higher in anticoagulation group than in non-anticoagulation group (OR=4.16, 95% CI=1.88-9.20, P=0.0004). The heterogeneity was not significant in the meta-analysis.

CONCLUSION

Anticoagulation could achieve a relatively high rate of portal vein recanalization in cirrhotic patients with PVT. Given that only a small number of non-randomized comparative studies are reported, randomized controlled trials are warranted to confirm the risk-to-benefit of anticoagulation in such patients, especially anticoagulation-related bleeding.