Etiology and consequences of thrombosis in abdominal vessels

Global research on portal vein thrombosis and liver transplantation: A bibliometric and visualized study

In recent years, the association between portal vein thrombosis and liver transplantation has extensive attention from physicians worldwide. However, there is no available literature on bibliometric analysis in this research area. Herein, we aimed to conduct a bibliometric analysis to identify the hotspots and frontiers of research related to portal vein thrombosis and liver transplantation. Documents published between 2002 and 2022 were retrieved and downloaded from the Web of Science Core Collection database. VOSviewer was utilized to generate a visualization network map of authors, nations, institutions, journals, and keyword co-occurrence/clustering. Additionaly, CiteSpace was used to analyze the keywords with the strongest bursts. A total of 1272 articles and reviews were extracted from the database. The author Marco Senzolo published the largest number of papers. The United States was the most prolific country, and Hope-Bochon (France) was the top productive institution. Liver Transplantation was the most prolific journal in the field. The most commonly identified keywords in the study were cirrhosis, risk factors, portal vein thrombosis, and management, as revealed by the keyword co-occurrence analysis. It is suggested that patients with cirrhosis, portal vein thrombosis prevention, and management measures for portal vein thrombosis have been prominet topics in recent years. Furthermore, an analysis of keywords with the strongest citation bursts highlighted pediatric liver transplantation, direct oral anticoagulants, and nonalcoholic fatty liver disease as current research trends. Research in portal vein thrombosis and liver transplantation exhibits a general upward trend. The latest hot topics within this area of study involve pediatric patients and nonalcoholic fatty liver disease.

Portal vein thrombosis on unenhanced MRI: a case series

Portal vein thrombosis (PVT) is usually diagnosed on contrast-enhanced CT, MRI or Doppler ultrasound. However, for patients with contraindications to intravenous contrast, its diagnosis is challenging. In these patients, PVT can be detected on unenhanced MRI using T2, T1 and diffusion-weighted imaging. These sequences may also help differentiate between bland PVT, portal pyemia and tumour thrombus. This case series aims to highlight the various appearances of PVT on unenhanced MRI.

Angiographic patterns of portal venous system in children with extrahepatic portal hypertension and its etiological and clinical relevance

PURPOSE

To study the relationship between the angiographic pattern of extrahepatic portal vein obstruction (EHPVO) and its etiology and clinical manifestations.

METHODS

Clinical, etiological, and angiographic findings in 155 children with EHPVO were reviewed. Anatomy of extrahepatic portal venous system (EPVS) was categorized into five imaging patterns. Assessment of the severity of esophageal and gastric varices (EV and GV) was performed by upper gastrointestinal endoscopy.

RESULTS

Based on multislice CT angiography, most commonly observed pattern of EHPVO was type I (48.4%) and type II (29%). According to anamnesis, 68 (43.8%) children had pathological conditions in neonatal period. Of these, 35 (22.6%) had an umbilical vein catheterization, 11 (7.1%) had a history of omphalitis, and 9 (5.8%) had prolonged jaundice. Thirteen (8.4%) patients had various septic conditions in neonatal period and it was more common associated with widespread thrombosis throughout the EPVS (type 5)-28% of observations. Significantly lower risk of bleeding from EV (p = 0.01) was noted in children with type IV pattern, whereas children with type III and V patterns had higher grades of EV.

CONCLUSION

Angiographic pattern of portomesenteric occlusion may provide a clue to its etiology, and clinical manifestation, especially in children with widespread thrombosis throughout the EPVS.

A Rare Postoperative Complication of Acute Appendicitis: Portal Vein Thrombosis Required Small Intestine Resection

This case report aims to present the diagnosis and treatment process of portal vein thrombosis, which occurred one week after laparoscopic appendectomy and required small bowel resection. A thirty-eight-year-old man was admitted with abdominal pain in the periumbilical and epigastric regions. He had a history of appendectomy and occlusive cerebrovascular disease. In the physical examination of the abdomen, tenderness was detected in the epigastric region on deep palpation. Leucocytosis, increased levels of alanine transaminase level, aspartate transaminase, gamma-glutamyl transferase, lactate dehydrogenase, c-reactive protein, and d-dimer were detected in laboratory analyses. CT scan revealed total thrombus in the portal vein, oedema in the segment of approximately 10 cm in the distal ileum, and free fluid in the pelvic region. Enoxaparin sodium was started. During follow-up, widespread defence and rebound in all quadrants of the abdomen occurred. 20 cm ileal resection with end ileostomy was performed. Enoxaparin sodium treatment was continued. On the 6th day of the service follow-up, the patient had left leg pain, and a subacute thrombus was detected in the main femoral, superficial femoral and deep femoral veins on doppler USG. Edoxaban tosylate 60 mg tablet every 24 hours started as an anti-coagulant treatment, and the patient was discharged without complications on the 18th day of hospitalisation.

Meta-analysis and systematic review: Prevalence, graft failure, mortality, and post-operative thrombosis in liver transplant recipients with pre-operative portal vein thrombosis

AIMS

This study seeks to evaluate the association between pre-transplant portal vein thrombosis (PVT) and overall survival, graft failure, waitlist mortality, and post-operative PVT after liver transplantation.

METHODS

A conventional pairwise meta-analysis between patients with and without pre-transplant PVT was conducted using hazard ratios or odds ratios where appropriate.

RESULTS

Prevalence of preoperative PVT was 11.6% (CI 9.70-13.7%). Pre-operative PVT was associated with increased overall mortality (HR 1.45, 95% CI 1.27-1.65) and graft loss (HR 1.58, 95% CI 1.34-1.85). In particular, grade 3 (HR 1.59, 95% CI 1.00-2.51) and 4 (HR 2.24, 95% CI 1.45-3.45) PVT significantly increased mortality, but not grade 1 or 2 PVT. Patients with PVT receiving living donor (HR 1.54, 95% CI 1.24-1.91) and deceased donor (HR 1.52, 95% CI 1.21-1.92) liver transplantation had increased mortality, with no significant difference between transplant types (P = .13). Furthermore, pre-transplant PVT was associated with higher occurrence of post-transplant PVT (OR 5.06, 95% CI 3.89-6.57). Waitlist mortality was not significantly increased in patients with pre-transplant PVT.

CONCLUSION

Graft failure, mortality, and post-operative PVT are more common in pre-transplant PVT patients, especially in grade 3 or 4 PVT. Prophylactic anticoagulation can be considered to reduce re-thrombosis and improve survival.

Portal Vein Thrombosis after the Consumption of Date Seed Powder: A Case Study

Date seeds can be used as ingredients to enhance the nutritional value of some functional foods for human consumption as well as additives in pharmaceutical and cosmetic industries. However, there are no reports on the complications of date seeds after oral consumption. We currently report a patient with no history of gastrointestinal disease, who has been admitted to the hospital with portal vein thrombosis (PVT) and suffered from complications.

Current concepts in portal vein thrombosis: etiology, clinical presentation and management

OBJECTIVE

The aim of this article is to focus on etiology, risk factors, clinical presentation and classification systems of acute and chronic PVT as well as focusing on current diagnostic and therapeutic options for the management of acute and chronic PVT.

RESULTS

PVT represents a serious clinical concern in cirrhotic patients and in those with specific local or systemic risk factors. The rate and extent of thrombus formation can significantly impact patient presentation and the resulting clinical outcomes. The presentation of acute PVT can range from abdominal pain to intestinal ischemia/infarction and even death, while chronic PVT can remain clinically silent. A number of imaging modalities including US, CT and MRI can be used to confirm the diagnosis. In addition to addressing underlying risk factors, AC therapy forms a cornerstone of treatment and has demonstrated efficacy in both acute and chronic settings. Proper caution should be used when initiating AC therapy in cirrhotic patients given their underlying coagulopathic status with attention now being paid to NOACs and LMWH. For patients with bowel ischemia, extensive thrombosis, contraindications or poor response to AC, or for those with co-morbidities that preclude AC, minimally invasive endovascular techniques offer alternative treatment options.

CONCLUSION

Familiarity with the etiology, clinical presentation and classification of PVT optimize early detection and incorporate effective therapeutic options, the management of these complex patients should be undertaken by a multidisciplinary team. Minimally invasive catheter-based therapies and endovascular portosystemic shunt creation demonstrated efficacy in the treatment of AC-resistant patients and for patients with extensive or complicated disease.

Portomesenteric Venous Thrombosis Post-Laparoscopic Sleeve Gastrectomy: Do Energy Systems Pose as Instigating Factor to This Infrequent Complication?

Background

Portomesenteric venous thrombosis (PMVT), a rare complication after laparoscopic sleeve gastrectomy (LSG). Severe consequences are owed to a high risk of bowel ischemia. Our aim is to present a series of patients who developed PMVT after LSG, highlighting the potential role of the vessel sealer and divider as a risk factor.

Methods

Medical records of seven patients who underwent LSG and developed PMVT from April 2010 to January 2019, at King Abdullah University Hospital and Jordan University Hospital, Jordan were reviewed. Our findings were studied, audited, and compared with published data.

Results

A sum of 4900 patients underwent LSG, 7 (0.14%) developed PMVT. The mean age and body mass index (BMI) were 36.8 years and 45 kg/m², respectively. Four were women. Epigastric pain radiating to the back was the presenting symptom at a median time of 9 days after surgery. Computed tomography (CT) of the abdomen confirmed the diagnosis. Five patients presented with a total portal vein thrombosis (PVT), one with splenic vein thrombosis and one with dual portal and mesenteric vein thrombosis.

Conclusion

Portomesenteric venous thrombosis is a relatively uncommon complication following LSG. Early recognition is required to avoid catastrophic outcomes. The role of energy systems in the development of PMVT remains unknown and requires further elaboration.

Randomized controlled trial of rivaroxaban versus warfarin in the management of acute non-neoplastic portal vein thrombosis

BACKGROUND AND AIM

Anticoagulation therapy is the main line of treatment for acute portal vein thrombosis (PVT) in the absence of cirrhosis. However, the use of this therapy in cirrhotic PVT is still with doubtful evidence. We aimed to evaluate the efficacy and safety of rivaroxaban compared to warfarin for the management of acute non-neoplastic PVT in Hepatitis C virus (HCV)-related compensated cirrhosis.

METHODS

Out of 578 patients with chronic HCV infection, 80 patients with acute PVT who had undergone splenectomy due to hypersplenism and 4 patients with acute PVT due to portal pyemia were selected. The patients were randomly assigned (1:1) to the study group (n = 40), in which the patients received rivaroxaban 10 mg/12 h, or the control group (n = 40), in which the patients received warfarin.

RESULTS

In the rivaroxaban group, the resolution of PVT was achieved in 34 patients (85%) within 2.6 ± 0.4 months and delayed, partial recanalization after 6.7 ± 1.2 months (n = 6.15%). Complications such as major bleeding, abnormal liver functions, death, or recurrence did not occur during treatment, and patients in this group showed improved short-term survival rate (20.4 ± 2.2 months) compared to the survival rate in the control group (10.6 ± 1.8 months) in which warfarin achieved complete resolution in 45% of patients. Complications such as severe upper GI tract bleeding (43.3%), hepatic decompensation (22.5%), progression to mesenteric ischemia (12.5%), recurrence (10%), and death (20%) were observed in the control group. The duration until complete resolution of thrombus correlated with age, the extent of the thrombus, creatinine level, and MELD score. The recurrence after complete resolution of thrombus correlated with age, the extent of the thrombus, thrombogenic gene polymorphism, and the use of warfarin.

CONCLUSION

Rivaroxaban was effective and safe in acute HCV-related non-neoplastic PVT with improved short-term survival rate; ClinicalTrials.gov Identifier: NCT03201367.

Incidence, Management, and Implications of Visceral Thrombosis in Pancreatic Ductal Adenocarcinoma

BACKGROUND

Visceral or splanchnic thrombosis is defined as thrombi within the hepatoportal venous system, including portal (PV), mesenteric (MV), and splenic vein (SV), as well as thrombi in renal or gonadal veins. There are limited data to evaluate the prognostic significance, incidence, and clinical management of visceral thromboses in patients with pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

We conducted an analysis of 95 patients treated at Memorial Sloan Kettering Cancer Center with PDAC who had a visceral thrombosis.

RESULTS

A total of 153 visceral thromboses (VsT) were identified in 95 patients (n = 51, 54% woman). A total of 36 patients (37%) had locally advanced disease, and n = 59 (62%) had metastatic disease. Systemic therapies received included FOLFIRINOX (n = 57, 60%) and GC/PTX (n = 27, 28%). All VsT events were incidentally detected. Overall survival of cohort was 12.3 months (range, 10.2-14.4 months). Visceral thrombosis incidence in the cohort was as follows: portal vein (PV) (45%), MV (26%), SV (17%), and gonadal veins (8%). Time to develop first VsT was 4.3 months (range, 3-5.6 months), and time to death from VsT development was 1.87 months (range, 0.8-2.8 months). Forty-five patients (47%) developed a second VsT. Sixty percent had a Khorana risk score of > 3. Thirty-nine patients (41%) were treated with short-term anticoagulation (AC) (< 1 month) (low-molecular-weight heparin, n = 34). Forty-five patients (47%) were treated with long-term AC (> 1 month) (low-molecular-weight heparin, n = 32; 23 were transitioned to an oral anticoagulant). Twenty-two patients (23%) were not treated with AC. Eight patients (8%) had a bleeding complication from AC. Portal vein thrombosis had the shortest overall survival at 3.6 months (range, 2.3-4.8 months).

CONCLUSION

In PDAC, VsT can frequently present as an incidental finding on routine abdominal imaging. The most common location is PV, followed by MV and SV. We observed that AC is underutilized in this setting despite a low bleeding complication rate. PV was associated with the least overall survival of the VsT. Future large prospective studies should explore the role of AC and value in this setting.

Visceral Thromboses in Pancreas Adenocarcinoma: Systematic Review

Within gastrointestinal malignancies, primary hepatocellular carcinoma and pancreatic ductal adenocarcinoma (PDAC) are frequently associated with visceral thromboses (VT). Thrombus formation in the portal (PVT), mesenteric (MVT), or splenic vein (SVT) system leads to portal hypertension and intestinal ischemia. VT in PDAC may convey a risk of increased distal thrombosis and poses therapeutic uncertainty regarding the role of anticoagulation. An increasing number of reports describe VT associated with PDAC. It is possible that early diagnosis of these events may help reduce morbidity and speculatively improve oncologic outcomes. To perform a systematic review to study PVT, MVT, and SVT associated with PDAC, and to provide a comprehensive review. Medline/PubMed, Embase, Web of Science, Scopus, and the Cochrane Library. Data Extraction and Assessment: Two blinded independent observers extracted and assessed the studies for diagnosis of PVT, MVT, and SVT in PDAC. Studies were restricted to English-language literature published between 2007 and 2016. Eleven articles were identified. Five case reports and 7 retrospective studies were found, with a total of 127 patients meeting the inclusion criteria. The mean age at diagnosis was 64 years. PVT was found in 35% (n = 46), SVT in 52% (n = 65), and MVT in 13% (n = 15). Mean follow-up time was 26 months. Only 3 of the selected articles studied the impact of anticoagulation in VT. All patients with nonvisceral thrombosis (eg, deep-vein thrombosis, pulmonary emboli) were therapeutically treated; in contrast, patients with VT only rarely received treatment. VT in PDAC is a frequent finding at diagnosis or during disease progression. Evidence to guide treatment choices is limited, and current management is based on inferred experience from nononcologic settings. Anticoagulation appears to be safe in VT, with most of the large studies recommending a careful assessment for patients at a high risk of bleeding.

Portomesenteric Vein Thrombosis Post-Laparoscopic Sleeve Gastrectomy: Case Series and Literature Review

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is today one of the leading procedures in bariatric surgery, and portomesenteric vein thrombosis (PMVT) has been reported as one of its rare complications. The purpose of this study is to determine the prevalence, clinical presentation, and outcomes of PMVT in patients undergoing LSG.

METHODS

A retrospective study of a database of all post-LSG patients was conducted on the patients who developed PMVT post-LSG from July 2011 to March 2016, at Amiri Hospital, Kuwait.

RESULTS

A total of 2280 patients underwent LSG during the study period. Nine (0.39%) patients were diagnosed with PMVT post-LSG. Diagnosis was confirmed by CT scan for eight patients, and one had urgent laparotomy. The median age was 34 years (20-50), and there were 7 women and 2 men. Median preoperative body mass index (BMI) was 42 kg/m² (37.5-74.6), and median operative time was 80 min (60-150). The median post-operative anticoagulation duration was 4 days (2-22). The median onset of diagnosis after the surgery was 28 days (18-453), and two patients had a positive thrombophilia study. All patients were treated medically except one patient who underwent urgent laparotomy for small bowel necrosis and eventually had small bowel transplant.

CONCLUSIONS

PMVT post-LSG is a rare but possibly dangerous complication. It should be suspected with patients presenting with unresolving abdominal pain. Treatment is mainly conservative and surgical intervention might be needed for small bowel necrosis. Extended anticoagulation prophylaxis is a hypothesis for patients after LSG, and may play a role in preventing PMVT.

Portal vein thrombosis after cesarean section in a patient on prolonged bed rest due to threatened preterm labor

Portal vein thrombosis is a rare but life-threatening complication during pregnancy and postpartum period. Color Doppler ultrasound is useful for prompt diagnosis. Although the risk of complications should be considered, successful pregnancy with comorbid portal vein thrombosis is possible with appropriate anticoagulation therapy and close monitoring.

Serum omentin and vaspin levels in cirrhotic patients with and without portal vein thrombosis

AIM

To investigate serum omentin and vaspin levels in cirrhotic patients; and to assess the relationship of these levels with hemostatic parameters, metabolic abnormalities, cirrhosis severity and etiology.

METHODS

Fifty-one cirrhotic patients (17 with portal vein thrombosis) were analyzed. Serum omentin and vaspin levels were measured with commercially available direct enzyme-linked immunosorbent assays (ELISAs). To assess platelet activity, the following tests were performed using a MULTIPLATE^®PLATELET FUNCTION ANALYZER: (1) an ADP-induced platelet activation test; (2) a cyclooxygenase dependent aggregation test (ASPI test); (3) a von Willebrand factor and glycoprotein Ib-dependent aggregation (using ristocetin) test (RISTO test); and (4) a test for thrombin receptor-activating peptide-6 induced activation of the thrombin receptor, which is sensitive to IIb/IIIa receptor antagonists.

RESULTS

Omentin, but not vaspin, serum concentrations were significantly decreased in patients with portal vein thrombosis (PVT) (P = 0.01). Prothrombin levels were significantly increased in patients with PVT (P = 0.01). The thrombin receptor activating peptide (TRAP) test results were significantly lower in the PVT group (P = 0.03). No significant differences in adipokines serum levels were found regarding the etiology or severity of liver cirrhosis assessed according to the Child-Pugh or Model of End-Stage Liver Disease (MELD) scores. There was a significant increase in the TRAP (P = 0.03), ASPI (P = 0.001) and RISTO high-test (P = 0.02) results in patients with lower MELD scores. Serum omentin and vaspin levels were significantly down-regulated in patients without insulin resistance (P = 0.03, P = 0.02, respectively). A positive relationship between omentin and vaspin levels were found both when all of the patients were analyzed (r = 0.41, P = 0.01) and among those with PVT (r = 0.94, P < 0.001).

CONCLUSION

Serum omentin levels are increased in patients without PVT. Cirrhosis origin and grade do not affect omentin and vaspin levels. The analyzed adipokines do not influence platelet activity.

Portal vein thrombosis in cirrhosis is not associated with intestinal barrier disruption or increased platelet aggregability

OBJECTIVE

Portal vein thrombosis (PVT) is a common complication of cirrhosis, but its pathogenesis is unclear. We tested the hypotheses that PVT is the result of platelet hyperactivity or intestinal barrier disruption.

METHODS

This study included 49 patients with cirrhosis (15 females) of mixed etiology. Based on spiral computed-tomography, the patients were divided into two groups: with PVT (n=16) and without PVT (n=33). Serum biomarkers of intestinal barrier integrity were endotoxins and zonulin, and platelet activity was assessed with multiple electrode aggregometry.

RESULTS

The levels of endotoxin (43.5±18.3ng/ml vs. 36.9±7.5ng/ml; P=0.19) and zonulin (56.3±31.1ng/ml vs. 69.3±63.1ng/ml; P=0.69) were not different between the patients with and without PVT. Moreover, endotoxin and zonulin did not correlate with the coagulation and platelet parameters. The platelet aggregability measured with the TRAP and the ADP tests was decreased in PVT patients. In the logistic regression analysis the PVT incidence was related to the levels of D-dimer and bilirubin as well as the TRAP test results. Patients with PVT presented with significantly higher levels of D-dimer (4.45±2.59 vs. 3.03±2.97mg/l; P<0.05) and prothrombin levels (175±98.8μg/ml vs. 115±72.9μg/ml; P<0.05) than patients without thrombosis. PVT could be excluded with a 90% negative predictive value when the D-dimer level was below 1.82mg/l.

CONCLUSIONS

Endotoxemia and platelet activity are not determinants of PVT in patients with cirrhosis. The D-dimer measurement has diagnostic significance for PVT in patients with liver cirrhosis.

Abdominal thrombotic complications following bariatric surgery

BACKGROUND

Thrombotic events involving the portal-splenic-mesenteric venous system (PSMVT) are rare but potentially lethal after bariatric surgery.

OBJECTIVES

To investigate the incidence, clinical presentation, management, and outcome of thrombotic events after bariatric surgery.

SETTING

Two university hospitals.

METHODS

A retrospective review of individuals who underwent bariatric surgery between January 2006 and December 2015.

RESULTS

Overall, 4386 patients underwent bariatric surgery (laparoscopic sleeve gastrectomy [LSG; n = 2886], laparoscopic Roux-en-Y gastric bypass [n = 762], laparoscopic adjustable gastric banding [n = 668], and biliopancreatic diversion [n = 70]). Mechanical (thigh-length pneumatic compression stockings) and pharmacologic thromboprophylaxis (40 mg enoxaparin daily, starting 12 hours after surgery until discharge) was provided for all patients. A minority of patients (n = 543, 12.4%) also received an extended course of enoxaparin for 1-4 weeks after discharge. We observed 16 cases of PSMVT, all after LSG, with an incidence of .55% (16/2886). Twelve additional patients experienced deep vein thrombosis and 6 had pulmonary embolism. Follow-up imaging indicated complete resolution in all cases, with no sequelae, recurrent thrombosis, or mortality. The overall thrombosis rate was significantly lower in patients who received an extended course of anticoagulation after LSG (P = .01) and after any type of bariatric surgery (P = .02).

CONCLUSIONS

PSMVT was found to occur uncommonly after LSG. Prompt diagnosis and anticoagulation therapy led to favorable outcomes in most cases. Significantly lower rates of thrombosis were found in patients who received an extended course of anticoagulation. We support its use for at least 1 week after discharge.

Management and conduct of vascular diseases of the portal system

Aneurysms and thromboses of the portal vein are rare pathologies of the portal system that commonly follow an asymptomatic course. The vast majority of cases are diagnosed as incidental findings during imaging studies. Symptoms of aneurysms are the result of mass effects, while thrombosis symptoms are a function of the liver's ability to form a collateral circulation network in the thrombosis. The scant experience with such cases poses a dilemma for patient management and so the vast majority of authors choose an expectant approach with rigorous patient surveillance and only intervene in symptomatic patients. We report one case of an aneurysm of the portal vein and one case of portal vein thrombosis and discuss management and observation of these patients.

Portal vein thrombosis

Portal vein thrombosis (PVT) is a rare event in the general medical setting that commonly complicates cirrhosis with portal hypertension, and can also occur with liver tumors. The diagnosis is often incidental when a thrombus is found in the portal vein on imaging tests. However, PVT may also present with clinical symptoms and can progress to life-threatening complications of ischemic hepatitis, liver failure, and/or small intestinal infarction. This article reviews the pathophysiology of this disorder, with a major focus on PVT in patients with cirrhosis, and presents detailed guidelines on optimal diagnostic and therapeutic strategies.

Review article: portal vein obstruction--epidemiology, pathogenesis, natural history, prognosis and treatment

BACKGROUND

Portal vein obstruction may be due to portal vein thrombosis (PVT) or its sequale, the portal cavernoma. PVT is a common complication in liver cirrhosis, however, it may also occur as a primary vascular disorder, in absence of any liver disease.

AIM

To review the current knowledge on nomenclature, etiology, pathophysiology, clinical presentation, diagnostic workup and management of adult patients with obstruction in the portal vein, either as a primary vascular disease in adults, or as a complication of liver cirrhosis.

METHODS

A structured search in PubMed was performed using defined keywords (portal vein obstruction, extra-hepatic portal vein obstruction, PVT and portal cavernoma), including full text articles and abstracts in English language.

RESULTS

Several causes, operating both at local and systemic level, might play an important role in the pathogenesis of PVT. Frequently, more than one risk factor could be identified; however, occasionally no single factor is discernible. Diagnosis of portal vein obstruction depends on clinical presentation, imaging and laboratory investigations. Prompt treatment greatly affects the patient's outcome.

CONCLUSIONS

Portal vein obstruction occurring either due to thrombosis in the portal vein or due to the portal cavernoma, can contribute to significant morbidity and mortality in patients with or without cirrhosis. In recent years our understanding of etio-pathogenesis of portal vein obstruction has evolved tremendously, which has led to significant improvement in treatment outcomes. There are still areas where more studies are needed to better clarify the management issues of portal vein obstruction.

Extrahepatic portal vein obstruction in Egyptian children

BACKGROUND AND AIM

Extrahepatic portal vein obstruction (EHPVO) is an important cause of portal hypertension in children. The aim of this study was to describe the clinical presentation, possible risk factors, upper gastrointestinal endoscopic findings, and treatment modalities of children with EHPVO.

METHODS

After ethical approval of our study protocol by our institution review board, we analyzed available data from medical records of patients with EHPVO presenting to the Pediatric Hepatology Unit, Cairo University Pediatric Hospital, Egypt, for a period of 15 years from January 1996 to December 2010.

RESULTS

The study included 169 patients. Their ages at presentation ranged from 1 month to 12 years (median 2.5 years, interquartile range 5); 101 were boys. Hematemesis was a presenting symptom in 58%, splenomegaly was present in 87%, esophageal varices were present in 94%, and fundal varices were present in 23%. Possible risk factors, in the form of umbilical catheterization, umbilical sepsis, and exchange transfusion, were elicited in 18%. Propranolol was associated with reduction in bleeding episodes (P < 0.001), but was associated with increased chest symptoms (P < 0.01). Both injection sclerotherapy and band ligation were effective in the management of bleeding varices and for primary and secondary prophylaxis; however, injection sclerotherapy was associated with the development of secondary gastric varices (P = 0.03).

CONCLUSIONS

This large study of children with EHPVO demonstrates the efficacy of propranolol in the reduction of gastrointestinal bleeding in children with EHPVO. Both injection sclerotherapy and band ligation were effective in the management of esophageal varices, although the former was associated with the development of secondary gastric varices. Randomized clinical trials to choose the best modalities for the management of portal hypertension in children are still lacking.

Acute superior mesenteric venous thrombosis: transcatheter thrombolysis and aspiration thrombectomy therapy by combined route of superior mesenteric vein and artery in eight patients

PURPOSE

To assess the feasibility, effectiveness, and safety of catheter-directed thrombolysis and aspiration thrombectomy therapy by combined route of superior mesenteric vein and artery (SMV+SMA) for acute superior mesenteric venous thrombosis (ASMVT).

METHODS

This retrospective study reviewed eight ASMVT patients with transcatheter direct thrombolysis and aspiration thrombectomy therapy via SMV and indirect thrombolysis via SMA during a period of 14 months. The demographics, etiology, risk factors, therapeutic effect, complications, mortality, and follow-up of the study population were assessed. Anatomic and imaging classification of location and extent of thrombus at diagnosis and degree of thrombus lysis were described.

RESULTS

Technical success was achieved with substantial improvement in symptoms and thrombus resolution after thrombolytic therapy in all patients. The local urokinase infusion by SMA and SMV was performed for 5-7 (6.13 ± 0.83) and 7-15 (12 ± 2.51) days. Anticoagulation was performed catheter-directed and then orally throughout hospitalization and after discharge. Four patients required delayed localized bowel resection after thrombolytic therapy with no death. Thrombolytic therapy was not interrupted despite minor bleeding at the puncture site in two patients and sepsis in another two postoperatively. Nearly complete removal of thrombus was demonstrated by contrast-enhanced CT scan and portography before discharge. Patients were discharged in 10-27 (19.25 ± 4.89) days after admission. No recurrence developed during the follow-up of 10-13 (12.13 ± 0.99) months.

CONCLUSIONS

Catheter-directed thrombolytic and aspiration therapy via SMV+SMA is beneficial for ASMVT in avoiding patient death, efficient resolving thrombus, rapid improving symptoms, reversing extensive intestinal ischemia, averting bowel resection, or localizing infarcted bowel segment and preventing short bowel syndrome.

Revisiting extra hepatic portal vein obstruction in children from the north Indian gangetic plain

OBJECTIVES

To study the demographic features, etiology, clinical, radiology and laboratory findings in children with Extra hepatic portal vein obstruction (EHPVO) from the North Indian Gangetic Plain.

METHODS

A prospective analysis of 53 patients of EHPVO (<14 y of age) was done. Data for clinical presentation, laboratory workup, endoscopic procedures, growth and development, management and outcome were analyzed.

RESULTS

A total of 53 patients (32 male, 21 female) with mean age of 8.66 ± 3.32 y at presentation were included. Growth retardation was present in 30 (56.60 %) patients at time of diagnosis. The most common presenting symptoms were upper gastrointestinal bleeding (86.80 %) and an incidental finding of splenomegaly (13.2 %). Hematological parameters of hypersplenism were present in 9 (17 %) patients. Protein C (PC), Protein S (PS), antithrombin III (AT) deficiency were found in 8 (20 %), 4 (10 %) and 6 (15 %) of the patients respectively in 40 patients tested. On first endoscopy, esophageal varices were present in all patients. Endoscopic sclerotherapy (EST)/band ligation (EBL) was performed in 46 bleeder patients and success rate was 83.3 % for sclerotherapy and 90 % for band ligation.

CONCLUSIONS

The etiology of EHPVO in the majority of patients remains elusive. It results in impaired somatic growth. Sclerotherapy and endoscopic banding are effective means for treatment for bleeding varices. It is still not clear whether deficiency of anticoagulant proteins is a primary event or secondary to disease process.

Portal Cavernoma during Pregnancy

Portal vein thrombosis (PVT) is characterized by the obstruction of the portal venous system. The venous obstruction can be partial or complete and it is caused by thrombogenic conditions (acquired or hereditary) or nonthrombotic factors. The acquired conditions include abdominal inflammation, infections, surgery, myeloproliferative disorders, obesity, oral contraceptive intake, pregnancy, and postpartum period. Occasionally, it is not possible to recognize any overt cause of PVT. During pregnancy there is an increased venous thromboembolism risk mainly in the systemic venous system and the PVT can occur, but there are no data about its exact prevalence, etiology, and outcome. The portal cavernoma is the cavernomatous transformation of the portal vein. It is a consequence of chronic PVT and occurs when myriads of collateral channels develop to bypass the occlusion. The clinical presentation includes hematemesis due to variceal bleeding, ascites or anaemia, and splenomegaly. The cavernous transformation of the portal vein is easily diagnosed by sonography. We report our case of a 32-year-old, gravida 3 para 2, pregnant woman admitted to our hospital at 13 weeks and 1 day of gestation, clinically asymptomatic. Laboratory test, ultrasound, and endoscopic evaluation were negative. After a detailed counseling, the patient decided on termination of pregnancy at 15 weeks and 1 day of gestation.

Mesenteric vein thrombosis after laparoscopic sleeve gastrectomy

Mesenteric vein thrombosis is a rare complication of bariatric laparoscopic surgery. We report a case of a 47-year-old man with obesity who had mesenteric vein thrombosis 14 days after laparoscopic sleeve gastrectomy. He was treated with heparin anticoagulation with a good therapeutic response. This case and literature review illustrate that mesenteric vein thrombosis has to be included in the differential diagnosis of abdominal pain after a bariatric procedure and listed formally as a complication of bariatric surgery.

Portal vein thrombosis: a clinician-oriented and practical review

With advances in modern imaging techniques, portal vein thrombosis (PVT) is being increasingly diagnosed. It has a wide ranging clinical spectrum from being an asymptomatic state to a potentially life-threatening situation. It is not unusual to find it as an incidental finding in the abdominal imagings done for other reasons. It is commonly associated with cirrhosis and abdominal malignancies and also has a strong association with prothrombotic disorders. It is often difficult for the clinicians to decide whether PVT is acute or chronic. This poses great challenges to its management strategies that include anticoagulants, thrombolysis, and surgical options. Timely diagnosis and appropriate management have great bearings on its outcomes of morbidity and mortality. In this clinician-oriented review, we have provided a concise review of clinical aspects of PVT and discussed various management strategies while addressing the common questions that come to a physician's mind dealing with such a patient.

What really causes necrotising enterocolitis?

Background. One of the most serious gastrointestinal disorders occurring in neonates is necrotising enterocolitis (NEC). It is recognised as the most common intra-abdominal emergency and is the leading cause of short bowel syndrome. With extremely high mortality and morbidity, this enigmatic disease remains a challenge for neonatologists around the world as its definite aetiology has yet to be determined. As current medical knowledge stands, there is no single well-defined cause of NEC. Instead, there are nearly 20 risk factors that are proposed to increase the likelihood of developing NEC. Aims and Objectives. The aim of this project was to conduct a comprehensive literature review around the 20 or so well-documented and less well-documented risk factors for necrotising enterocolitis. Materials and Methods. Searches of the Medline, Embase, and Science direct databases were conducted using the words "necrotising enterocolitis + the risk factor in question" for example, "necrotising enterocolitis + dehydration." Search results were ordered by relevance with bias given to more recent publications. Conclusion. This literature review has demonstrated the complexity of necrotising enterocolitis and emphasised the likely multifactorial aetiology. Further research is needed to investigate the extent to which each risk factor is implicated in necrotising enterocolitis.

Evaluation of the presence of hereditary and acquired thrombophilias in Brazilian children and adolescents with diagnoses of portal vein thrombosis

OBJECTIVE

The aim of this study was to describe the prevalence of main hereditary thrombophilias, Janus kinase 2 (JAK2) V617F mutation, antiphospholipid antibody syndrome (APS), and hyperhomocysteinemia in Brazilian children and adolescents diagnosed with portal vein thrombosis (PVT) without associated hepatic disease.

METHODS

A cross-sectional study was carried out with 32 children with PVT in accompaniment at Hospital das Clínicas of the Universidade Federal de Minas Gerais from January 1990 to July 2011. Laboratory evaluation of thrombophilias was performed from September 2010 to July 2011.

RESULTS

Thirty-two patients were evaluated; 59% were boys. Median age at diagnosis was 2.4 years. Mean time of patients' accompaniment was between 4.7 and 5.2 years. The presence of hereditary and acquired thrombophilias occurred in 34.4% of patients, and 9 of them also showed other risk factors in the previous history evaluation. Risk factors were absent in the previous history of 18 patients (56.3%). Two patients showed persistent high titres of anticardiolipin antibodies. Hyperhomocysteinemia was not observed. One patient was heterozygous for factor V Leiden and prothrombin G20210A mutation (3.1%). Eleven patients (34.4%) showed heterozygous methylenetetrahydrofolate reductase (MTHFR) C677T, and no patient had the JAK2V617F mutation.

CONCLUSIONS

Even after investigation of main hereditary and acquired thrombophilia, PVT remains without apparent cause in most patients. Nevertheless, association of local and systemic risk factors seems to be important also in the pediatric age group. Therefore, despite the low prevalence, a complete investigation, which includes both hereditary and acquired thrombophilias, may be necessary.

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

CONTEXT

Portal vein thrombosis refers to a total or partial obstruction of the blood flow in this vein due to a thrombus formation. It is an important cause of portal hypertension in the pediatric age group with high morbidity rates due to its main complication - the upper gastrointestinal bleeding.

OBJECTIVE

To describe a group of patients with portal vein thrombosis without associated hepatic disease of the Pediatric Hepatology Clinic of the Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil with emphasis on diagnosis, presentation form and clinical complications, and the treatment of portal hypertension.

METHODS

This is a descriptive study of a series of children and adolescents cases assisted from January 1990 to December 2010. The portal vein thrombosis diagnosis was established by ultrasound.

RESULTS

Of the 55 studied patients, 30 (54.5%) were male. In 29 patients (52.7%), none of the risk factors for portal vein thrombosis was observed. The predominant form of presentation was the upper gastrointestinal bleeding (52.7%). In 20 patients (36.4%), the initial manifestation was splenomegaly. During the whole following period of the study, 39 patients (70.9%) showed at least one episode of upper gastrointestinal bleeding. The mean age of patients in the first episode was 4.6 ± 3.4 years old. The endoscopic procedure carried out in the urgency or electively for search of esophageal varices showed its presence in 84.9% of the evaluated patients. The prophylactic endoscopic treatment was performed with endoscopic band ligation of varices in 31.3% of patients. Only one died due to refractory bleeding.

CONCLUSIONS

The portal vein thrombosis is one of the most important causes of upper gastrointestinal bleeding in children. In all non febrile children with splenomegaly and/or hematemesis and without hepatomegaly and with normal hepatic function tests, it should be suspect of portal vein thrombosis. Thus, an appropriate diagnostic and treatment approach is desirable in an attempt to reduce morbidity and mortality.

What we should know about portal vein thrombosis in cirrhotic patients: A changing perspective

Portal vein thrombosis (PVT) is one of the most common complications occurring during the natural course of liver cirrhosis. Even though PVT is often asymptomatic, the worsening of liver function, an unexpected episode of gastrointestinal bleeding or ascitic decompensation may be landmarks of PVT development. Beyond these clinical manifestations, it is debated whether PVT really has an impact on liver cirrhosis natural history or rather represents only one of its consequences. Probably PVT development should not only be considered as a matter of impaired blood flow or pro-coagulation tendency. On one hand, PVT seems a consequence of the worsening in portal vein outflow due to the increased hepatic resistance in cirrhotic livers. On the other hand, vascular microthrombosis secondary to necroinflammation may cause liver ischemia and infarction, with loss of hepatic tissue (parenchymal extinction) which is replaced by fibrotic tissue. Therefore, PVT might also be considered as the overt manifestation of the liver fibrosing process evolution and anticoagulant therapy may thus have microscopic indirect effects also on the progression of liver disease. At present, a connection between PVT development and the progression of liver fibrosis/cirrhosis has not yet been demonstrated. Nevertheless, it is not clear if PVT development may worsen cirrhotic patients’ outcome by itself. Some authors tried to assess liver transplant benefit in PVT cirrhotic patients but data are contrasting. In this review, we will try to answer these questions, providing a critical analysis of data reported in literature.

Portal vein thrombosis following percutaneous transhepatic cholangiography-An unusual presentation of Prothrombin (Factor II) gene mutation

Portal vein thrombosis is an uncommonly reported complication of percutaneous transhepatic cholangiography (PTC). A thorough review of the available literature shows no reported cases. In this case, a 29 year old female presented on two separate occasions with portal vein thrombosis following PTC without drain placement. This unusual complication of image guided percutaneous biliary access is unreported in the literature and prompted evaluation of the patient’s coagulation parameters. A thrombophilia screen demonstrated a mutation in the Prothrombin (Factor II) gene. A thorough literature review shows no reported cases of portal vein thrombosis following percutaneous biliary access, is an unusual complication, and should raise suspicion of an underlying pro-coagulant state.

Splanchnic vein thrombosis in the mediterranean area in children

Abdominal venous thrombosis may present as splanchnic venous thrombosis (SVT) (occlusion of portal, splenic, superior or inferior mesenteric veins) or Budd- Chiari Syndrome (BCS) (thrombosis of inferior vena cava and/or hepatic veins). The aim of this review is to report the scanty data available for SVT in the South Mediterranean area. In one Egyptian study, the possible circumstantial risk factors for portal vein thrombosis (PVT) were found in 30% of cases: 19% neonatal sepsis, 8.7% umbilical catheterization, 6% severe gastroenteritis and dehydration. Another Egyptian study concluded that hereditary thrombophilia was common in children with PVT (62.5%), the commonest being factor V Leiden mutation (FVL) (30%). Concurrence of more than one hereditary thrombophilia was not uncommon (12.5%). The first international publication on hepatic veno-occlusive disease (VOD) in Egypt was in 1965 in children who rapidly develop abdominal distention with ascites and hepatomegaly. This disease was more frequent in malnourished children coming from rural areas; infusions given at home may contain noxious substances that were hepatotoxic and infections might play a role. VOD of childhood is rarely seen nowadays. Data from South Mediterranean area are deficient and this may be attributable to reporting in local medical journals that are difficult to access. Medical societies concerned with this topic could help distribute this information.

Is there a role for anticoagulants in portal vein thrombosis management in cirrhotic patients?

IMPORTANCE OF THE FIELD

Portal vein thrombosis (PVT) is one of the principal complications of liver cirrhosis. The estimated prevalence is < 1% in patients with a compensated disease; this increases to 8 - 25% in candidates for liver transplantation. Many determinants may influence PVT clinical presentation and its outcome.

AREAS COVERED IN THIS REVIEW

We report the actual knowledge regarding management of PVT and analyze the different therapeutic approaches, focusing particularly on the use of anticoagulants and their implications in the complex clinical setting of liver cirrhosis. We also describe the possible available preemptive strategies, as an early prophylactic management based on clinical, biochemical or radiological parameters may in the future reduce PVT incidence and complications, ameliorating patients' outcome.

WHAT THE READER WILL GAIN

The importance of an accurate PVT diagnosis and its implications in PVT management; a description of the different available therapeutic tools, their efficacy and their possible risks in different typologies of patients; the principal elements to choose a correct individualized therapy for PVT patients.

TAKE HOME MESSAGE

The challenge for clinicians is the early identification of PVT, in order to prevent frightening complications, such as variceal bleeding or mesenteric infarction, and to provide the best therapeutic management.

Portal vein thrombosis: Insight into physiopathology, diagnosis, and treatment

Portal vein thrombosis (PVT) is a relatively common complication in patients with liver cirrhosis, but might also occur in absence of an overt liver disease. Several causes, either local or systemic, might play an important role in PVT pathogenesis. Frequently, more than one risk factor could be identified; however, occasionally no single factor is discernable. Clinical examination, laboratory investigations, and imaging are helpful to provide a quick diagnosis, as prompt treatment might greatly affect a patient’s outcome. In this review, we analyze the physiopathological mechanisms of PVT development, together with the hemodynamic and functional alterations related to this condition. Moreover, we describe the principal factors most frequently involved in PVT development and the recent knowledge concerning diagnostic and therapeutic procedures. Finally, we analyze the implications of PVT in the setting of liver transplantation and its possible influence on patients’ future prognoses.

Viral cirrhosis: an overview of haemostatic alterations and clinical consequences

Viral hepatitis is a major health problem worldwide, the principal cause of cirrhosis and hepatocarcinoma. Once cirrhosis occurs, the consequences of liver dysfunction and portal hypertension become evident and, sometimes, life threatening for patients. Among the various complications of liver cirrhosis, the alteration of haemostatic balance is often a hard challenge for the clinician, since it is capable to predispose both to bleeding or thrombosis. In this review, we analyze the principal aspects of procoagulant, anticoagulant and fibrinolytic capacity of cirrhotic patients, which appears to be variably altered in all these aspects, not only in the direction of a tendency to bleeding. Laboratory investigations, at present, may provide only a partial representation of this condition, because of the impossibility to obtain a test capable to furnish a global overview of the haemostatic system and to reproduce in vivo conditions. Furthermore, we describe the pathophysiological mechanisms underlying bleeding manifestations and thrombosis development in cirrhotic patients, which should be considered not only as obvious consequences of the advanced liver disease but, rather, as the result of a complex interaction between inherited and acquired factors.

Rapid development of a hepatocellular carcinoma in isolated thrombosis of hepatic veins (classic Budd-Chiari syndrome): case report and review of literature

Budd-Chiari syndrome and membranous obstruction of the inferior vena cava frequently result in the development of mostly benign hepatic lesions. In cases of membranous obstruction of the inferior vena cava, which is prevalent mostly in the East, these lesions often progress to hepatocellular carcinoma. In contrast, malignant transformation has not yet been recognised in patients with isolated hepatic vein thrombosis. We report the case of a 37-year-old male Caucasian who presented with acute Budd-Chiari syndrome without involvement of the inferior vena cava. Despite porto-caval shunting, a hepatocellular carcinoma developed within several months. Three hepatic lesions were treated by radiofrequency thermal ablation until liver transplantation was performed. This report emphasises the possibility of malignant transformation of regenerative nodules in patients with disturbed hepatic perfusion in general. Physicians must be aware of this when assessing regenerative nodules, especially as no unambiguous predictors for the development of hepatocellular carcinoma have been identified so far.

Venous thrombotic emergencies

Thrombosis is a common complication of cancer, occurring in up to 15% of patients. This article reviews the diagnosis and management of the most common cancer-related thrombotic problem; deep venous thrombosis, pulmonary embolism, and catheterrelated thrombosis. Rarer entities, such as cerebral vein thrombosis and Budd-Chiari syndrome, are also reviewed.

Cytomegalovirus-associated superior mesenteric vein thrombosis treated with systemic and in-situ thrombolysis

A 56-year-old patient, first diagnosed with an acute cytomegalovirus infection, presented with progressive abdominal pain because of a superior mesenteric vein thrombosis for which he was treated with systemic thrombolysis and heparin in continuous infusion. As this therapy did not have the intended success after 5 days, an interventional radiological procedure was performed with local thrombolysis in the superior mesenteric artery resulting in recanalisation of the vein. Oral anticoagulation was initiated and continued for a period of 6 months. Mesenteric venous thrombosis is a relatively uncommon cause of mesenteric ischemia that can be associated with severe morbidity and significant mortality. With noninvasive techniques, it is possible to establish a diagnosis in the majority of the cases. The importance of an early diagnosis and therapy - not only with anticoagulation, but also thrombolysis in selected cases - is shown with this case and review of the literature.

Risk factors of thrombosis in abdominal veins

AIM: To estimate the prevalence of inherited and acquired thrombophilic risk factors in patients with abdominal venous thrombosis and to compare the risk factor profiles between Budd-Chiari syndromes (BCS) and splanchnic vein thrombosis (SVT).

METHODS: In this retrospective study, 36 patients with abdominal venous thrombosis were studied. The patients were divided into Budd-Chiari group (hepatic vein, IVC thrombosis) and splanchnic venous thrombosis group (portal, splenic, superior mesenteric veins) based on the veins involved. Hereditary and acquired thrombophilic risk factors were evaluated in all patients.

RESULTS: Twenty patients had SVT, 14 had BCS, and 2 had mixed venous thrombosis. Ten patients (28%) had hereditary and 10 patients (28%) acquired thrombophilic risk factors. The acquired risk factors were significantly more common in the SVT group (SVT vs BCS: 45% vs 7%, χ² = 5.7, P = 0.02) while hereditary risk factors did not show significant differences between the two groups (SVT vs BCS: 25% vs 36%, χ² = 0.46, P = 0.7). Multiple risk factors were present in one (7%) patient with BCS and in 3 patients (15%) with SVT. No risk factors were identified in 57% of patients with BCS and in 45% of patients with SVT.

CONCLUSION: Hereditary and acquired risk factors play an important role in the etiopathogenesis of abdominal venous thrombosis. Acquired risk factors are significantly more common in SVT patients while hereditary factors are similar in both groups.