Portal Obstruction Research Articles

Increased incidence of glomerulonephritis following spleno-renal shunt surgery in non-cirrhotic portal fibrosis

In a prospective study of 200 non-cirrhotic portal fibrosis (NCPF) patients, 7% had mild proteinuria and their renal biopsies showed mild mesangial proliferative glomerulonephritis (mes-PGN). The remaining 93% biopsies were normal. However, following the insertion of a spleno-renal shunt (SRS) for portal hypertension 32% of these patients developed nephrotic syndrome in five years. Renal histology revealed mesangiocapillary glomerulonephritis (MCGN) (18.5%), mes-PGN (9%), minimal change nephropathy (3%), and chronic sclerosing GN (1.5%). Immunofluorescence showed granular deposition of IgA and C3. IgA2 was the predominant form of Ig in the glomerular deposits, indicating that IgA in the immune complexes was derived from the gastrointestinal tract. Electron microscopy revealed electron dense deposits in the mesangium. In contrast to the NCPF patients who underwent a SRS for portal hypertension, the 200 patients in our study who underwent spleno-renal shunting because of extra hepatic portal obstruction did not have renal disease, nor did they develop renal disease during the five-year post-operative follow-up. Fifty percent of the glomerulonephritis (GN) in the NCPF group progressed to renal failure in five years; 46.6% continued to have proteinuria. Low serum complement, C3 (40%) and circulating immune complexes (14.8%) were detected in the glomerulonephritis group. Our study shows that: (i) there is a high rate of the occurrence of GN following SRS in NCPF patients, but not in those with normal livers; (ii) the type of GN is primarily IgA nephropathy; and (iii) the GN could be the result of defective hepatic reticuloendothelial function in the NCPF group that is worsened by the shunting procedure.

P-345 Long-term prognosis of idiopathic portal hypertension (IPH): Comparison with liver cirrhosis (LC) and extraphepatic portal obstruction (EHO)

P-345 Long-term prognosis of idiopathic portal hypertension (IPH): Comparison with liver cirrhosis (LC) and extraphepatic portal obstruction (EHO)

Hepatolithiasis associated with cholangiocarcinoma.

Hepatolithiasis is a risk factor for cholangiocarcinoma. It is difficult to make an accurate diagnosis before treatment. In a retrospective study, we identified characteristic clinical features of 103 patients with hepatolithiasis (group H) and 10 patients with hepatolithiasis associated with cholangiocarcinoma (group HC), and examined the methods for diagnosis and treatment. The main symptoms were abdominal pain, fever, and jaundice, although few patients in group HC had jaundice. The incidence of abnormal serum levels of carcinoembryonic antigen (CEA) in group HC was higher than in group H. The incidence of cholangiocarcinoma in cases in which most of the stones were present in the intrahepatic ducts of the left lobe (type I-L) was higher than the incidence in the other patients. Of the patients who underwent portography in group HC, portal veins in the portion of the liver containing the cholangiocarcinoma were not seen, and this region was atrophic in the operative specimens. The incidence of portal obstruction in portograms in group HC was higher than that in group H. The possibility of carcinoma should be kept in mind if there are high levels of CEA, if the location of the stones is classified as type I-L, or if portal veins cannot be seen on portograms. In such patients, liver resection should be considered because there may be undiagnosed cholangiocarcinoma.

Long-term results after nonshunt operations for esophageal varices in children

The clinical results of nonshunt operations for esophageal varices in 15 children were evaluated. The varices were caused by congenital extrahepatic portal obstruction (EHPO) in 10, liver cirrhosis or fibrosis (C/F) in 3, and idiopathic portal hypertension (IPH) in 2. The operative procedures were transthoracic esophageal transection with paraesophageal devascularization (TR) for 2 EHPO patients under 5 years of age, TR combined with splenectomy and paragastric devascularization (Sugiura procedure) for 11 (8 EHPO, 3 C/F), and splenectomy with devascularization (SP) or splenectomy for the 2 IPH patients. In the EHPO patient under 5 years of age, TR is associated with a likelihood of gastric or esophageal hemorrhage resulting from hypersplenism, gastric congestion, or persistent distal esophageal varices, which can be treated with partial splanic arterial embolization (PSE), endosclerotherapy, or an additional abdominal procedure. The Sugiura procedure has provided satisfactory long-term results, without rebleeding from esophageal varices, in patients with EHPO and C/F for 1 to 20 years. But EHPO patients who undergo the Sugiura procedure before age 6 can have gastric hemorrhage, because of mucosal congestion, for more than 10 years after the procedure, and selective gastric arterial embolization (GAE) might be necessary. In some EHPO patients, especially young ones who have variceal bleeding, a significant increase in hepatopetal portal flow may not develop, but hepatofugal natural shunts may progress. Therefore we recommend direct operative procedures, ie, TR for patients ≤6 years of age and a one- or two-stage Sugiura procedure for those over 7 years old. Nonoperative treatment such as PSE, GAE, and sclerotherapy were effective as adjunct therapeutic measures for managing postoperative bleeding problems. The function of the lower esophageal sphincter deteriorated transiently during the early postoperative period, but recovered to the preoperative level 6 months after the TR or Sugiura procedure.

Histopathological study of intrahepatic aberrant vessels in cases of noncirrhotic portal hypertension

Aberrant vessels, which are defined as dilated blood vessels immediately adjacent to the peripheral portal tract, appear under conditions of extrahepatic portal obstruction and nodular regenerative hyperplasia as well as idiopathic portal hypertension. Our study was undertaken to compare their morphological aspects in these three disease cases. Aberrant vessels were found in 84% of cases of idiopathic portal hypertension, 67% of cases of extrahepatic portal obstruction infantile type, 78% of cases of extrahepatic portal obstruction adult type and 83% of cases of nodular regenerative hyperplasia. They were divided into three types: type I--no communication with the portal vein, the lumen of which is normally open; type II--communication with the portal vein; and type III--no communication with the portal vein, which is occluded. The most common types of aberrant vessel were type III in idiopathic portal hypertension (51%), type I in extrahepatic portal obstruction infantile type (46%), type II in extrahepatic portal obstruction adult type (43%) and type III in nodular regenerative hyperplasia (45%). Serial sections revealed transition between types I, II and III, at frequencies between types II and III, types I and II, and types I and III of 35.7%, 33.7% and 30.6%, respectively. Aberrant vessels demonstrated the same immunoreactivity as portal veins for collagen type IV, laminin, factor VIII and ulex europaeus agglutinin-I. They were concluded to arise from the vasa septalis or inlet venules, which would be used as intrahepatic shunts draining portal blood flow blocked by stenosed portal veins. Increased portal pressure would be expected to enhance development of aberrant vessels.(ABSTRACT TRUNCATED AT 250 WORDS)

Portal cavernoma in congenital hepatic fibrosis. Angiographic reports of 10 pediatric cases.

A retrospective pediatric study of 30 angiograms in congenital hepatic fibrosis (CHF) was undertaken to analyze the different aspects of the portal venous system in this disease. Besides the classical angiographic signs (hepatofugal veins and intrahepatic duplications), a hepatopetal venous network was present in ten children, contrasting with the patency of the portal venous system. Analysis of the medical charts for these ten patients showed that the clinical signs and outcome were similar to classical CHF. Liver biopsies were available in six cases and, in addition to the diagnostic features of CHF, demonstrated paucity or absence of portal venules. This unusual association of hepatopetal and hepatofugal collateral veins in an intrahepatic block could be explained by hypoplasia or thrombosis of portal venules. Thus, the association between hepatomegaly and hepatopetal collateral veins without portal obstruction should be suggestive of CHF.

Natural history of Schistosoma mansoni infection in mice: egg production, egg passage in the feces, and contribution of host and parasite death to changes in worm numbers.

Mice, C57Bl/6N (B6) and BALB/cAnN (BALB), infected with Schistosoma mansoni were examined 8-26 weeks postinfection (PI) to estimate the fecundity of the worms and the contribution of death of worms and the death of heavily infected mice to the decrease in worm numbers in chronic infections. Portal worms were recovered by perfusion and the lungs were examined for parasites shunted from the portal circulation. Animals that died were more heavily infected than those that survived. Between eight and 12 weeks PI, this loss of worms resulted in a net decrease of approximately 19% of worm pairs in surviving BALB mice, but of only 4% in B6 mice. Loss of portal worms to the lungs after the eighth week of infection was 9-13% of portal worms in BALB mice and 3-4% in B6 mice. The estimated rates of egg production by S. mansoni decreased slightly with time in both strains of mice. At 12 and 20 weeks PI, tissue eggs per worm pair and eggs passed in the feces per worm pair often decreased as the intensity of infection increased. We do not consider the loss of worms in the murine host relevant to most infections in humans because of the high intensity of infection relative to body size in mice and the high frequency of severe portal obstruction in murine infections.

Treatment of bleeding esophagogastric varices due to extrahepatic portal hypertension: Results of portal-systemic shunts during 35 years

From 1958 to 1990, elective therapeutic portal-systemic shunt (PSS) procedures were performed for recurrent bleeding esophagogastric varices in 162 children and adults with extrahepatic portal hypertension (EHPH) resulting from portal vein thrombosis (PVT). The onset of EHPH was in childhood for at least 74% of patients. Of the 162 patients, 147 were eligible for and received 5 years of follow-up (100%), and 117 were eligible for and received 10 years of follow-up (100%). The longest follow-up was 35 years. The cause of PVT was unknown in 68%, neonatal omphalitis in 12%, umbilical vein catheterization in 8%, peritonitis in 6%, trauma in 4%, and thrombotic coagulopathy in 2%. The number of variceal bleeding episodes ranged from 2 to 18 (mean, 5.6). None of the patients had clinical, biochemical, or liver biopsy evidence of liver disease. Esophageal varices were demonstrated by endoscopy, and/or contrast x-rays, and/or angiography in all patients. Visceral angiography was always used to demonstrate the extent of portal obstruction and the veins available for shunting. Before referral, the following procedures had failed: endoscopic sclerotherapy (68 patients), splenectomy alone (32 patients), central splenorenal shunt with splenectomy (10 patients), transesophageal varix ligation (12 patients). Three types of PSS were used: (1) central side-to-side splenorenal without splenectomy (75 patients, 46%); (2) central end-to-side splenorenal with splenectomy (34 patients, 21%); and (3) mesocaval (end-to-side cavomesenteric) (53 patients, 33%). PSS reduced the mean corrected portal pressure from 292 to 28 mm saline. All patients survived the procedure and left the hospital (100%). The actuarial survival rate for 5 years is 99%, and for 10 years is 96%. Three of the 6 deaths were unrelated to EHPH or PSS. Shunt patency for up to 35 years was demonstrated in 98% of patients by angiography and/or ultrasonography. In four patients (2%), all of whom had end-to-side splenorenal shunts, shunt thrombosis and rebleeding developed 3, 4, 4, and 6 years (respectively) after PSS. These were the only patients who experienced rebleeding. A diligent and repeated effort was made to detect portal-systemic encephalopathy (PSE), and no instance of PSE was found during 3 to 35 years of follow-up. Liver function and morphology remained normal, and hypersplenism was corrected in all patients. Quality of life was good in 98% of patients, and 5 years after PSS 96% were gainfully employed, engaged in full-time homemaking, or attending school. We conclude that PSS is the most effective treatment for EHPH caused by PVT, and that patients should undergo PSS early in the course of variceal bleeding episodes.

LONG-TERM RESULTS AFTER THE MANAGEMENTS FOR ESOPHAGEAL VARICES IN CHILDREN

In a 26-year period from 1965 to 1991, treatments for esophageal varices have been performed in 26 children. Its long-term clinical results were discussed in this paper. Causes of esophageal varices were congenital extrahepatic portal obstruction (EHPO) in 16, idiopathic portal hypertension in 4, liver cirrhosis or fibrosis in 3, chronic hepatitis in 1, and metabolic liver disease in 2 patients. The total number of treatments came to 45 times. Operative procedures included transabdominal esophageal or gastric transection with paraeso-phageal devascularization on 16, splenectomy on 10, shunt surgery on 15, and endoscopic injection sclerotherapy on 3 patients. Longterm results after treatments of esophageal varices, shunt surgery groups had lower rehemorrhagic rates than others. It may be a fear that hepatic impairment can occur in a longterm follow up after shunt surgery, but no severe impairment has been seen even 10 to 29 years the operation. We recommend that selective shunt surgery might be the procedure of choice for rehemorrhagic esophageal varices in children as well as adults.

Oriental cholangiohepatitis: correlation between portal vein occlusion and hepatic atrophy.

The angiographic features of the hepatic vasculature in patients with oriental cholangiohepatitis and their relationship to liver atrophy remain unclear. We studied 11 patients with oriental cholangiohepatitis to define the spectrum of portal vein, bile duct, and parenchymal involvement by correlating findings on cholangiography, sonography, CT, and angiography. The portal veins appeared normal in five cases, pruned in four, and completely obstructed in two. This spectrum of appearances was found to correlate with the severity of liver atrophy. No massive arterioportal shunting was found in any patients in this series. The two patients with complete obstruction of the portal veins showed no evidence of malignancy at histologic examination of the resected specimen. It is concluded that the degree of portal vein obstruction correlates well with the degree of liver atrophy in patients with oriental cholangiohepatitis and that findings of complete central portal obstruction do not necessarily indicate associated malignancy.

Splenic and portal venous obstruction in chronic pancreatitis

The aim of this study was a prospective search for splenoportal venous obstruction (SPVO) in a medical-surgical series of 266 patients with chronic pancreatitis who were followed up a mean time of 8.2 years. SPVO was systematically searched for using ultrasonography and then confirmed by angiography or computed tomography. SPVO was found in 35 patients (13.2%) but was symptomatic in only two. Initial obstruction involved the splenic vein in 22 patients, the portal vein in 10, and the superior mesenteric vein in three. Since venous obstruction extended from the splenic to the portal vein in five patients, the prevalence of portal obstruction was 5.6% (15/266). Acute pancreatitis and pseudocysts were the probable cause of SPVO in 91.4% of our cases. Half the cases of splenic venous obstruction were related to pseudocysts of the caudal pancreas. Esophageal varices were found in two patients and gastric varices in four at the time of diagnosis and during follow-up. At the end of follow-up, 12 patients had undergone splenopancreatectomy (N = 11) or splenectomy (N = 1). Only one patient was operated on for massive esophageal variceal bleeding, and another patient died due to intractable colic variceal bleeding. In four of six patients operated on with portal vein obstruction, surgery was difficult due to venous collaterals. Ten patients were not operated on and 13 patients operated on were not treated for SPVO. The mean follow-up after diagnosis of SPVO for these final 23 patients was 28.9 months. None of these patients bled.(ABSTRACT TRUNCATED AT 250 WORDS)

Results of endoscopic variceal sclerotherapy: Influence of etiology of portal hypertension and hepatic functional status

In India 50% of patients with gastrointestinal bleeding bleed from esophageal varices. Causes of portal hypertension includes hepatic cirrhosis, non-cirrhotic portal fibrosis and extrahepatic portal obstruction. Endoscopic sclerotherapy is the treatment of choice to control continued active bleeding. Immediate hemostasis was not influenced by the etiology of portal hypertension. However, rebleeding episodes were lower, in extrahepatic portal vein obstruction than non-cirrhotic portal fibrosis and cirrhotic patients. Child's status significantly influenced recurrence of bleeding and mortality which was lower in child's A than B and lower in B than C irrespective of etiology. Results of long term sclerotherapy were also influenced by the etiology of portal hypertension and hepatic functional status. Sclerotherapy was most effective in patients of (EHO), than (NCPF) followed by cirrhosis of the liver.

A new experimental animal model of portal hypertension Intrahepatic portal obstruction by injecting DEAE-cross-linked dextran microspheres into the portal vein in the rabbit.

We proposed a new experimental animal model for portal hypertension in the female Japanese white rabbit by an intraportal injection of DEAE-cross-linked dextran microspheres (100 +/- 25 microns in diameter). Histology of the liver revealed portal obstruction by the injected microspheres in almost all portal triads, resulting in a foreign body granuloma. A sustained elevation of the portal pressure by a mean of 36.7% as compared with the basal value was observed for at least eight weeks in association with the portal-systemic collateral circulation demonstrated by portography, the radioisotope labeled microsphere method and histological examination of the esophagus and the liver. The elevation in portal pressure in the eighth week was associated with an increase in the portal blood flow determined at the main portal trunk. This was in accordance with the forward theory of the pathogenesis of portal hypertension. Since this model appears to show the two main conditions characteristic of portal hypertension persistent elevation of portal pressure and both extra- and intrahepatic portal collaterals, mimicking those in humans, portal obstruction by injecting DEAE-cross-linked dextran microspheres into the portal vein of the rabbit could provide a versatile model for portal hypertension.

A simple experimental model of total hepatectomy, hepatic ischemia and extrahepatic portal obstruction in rats using splenic transposition

The objective of this study was to develop an easy and simple experimental rat model of total hepatectomy, hepatic ischemia and extrahepatic portal obstruction. The first operation involved transposing the spleen with its scarified capsule in a subcutaneous pouch to produce portasystemic anastomosis. Total hepatectomy was easily performed in a lobe-by-lobe fashion 2 weeks following the first stage operation. Anhepatic rats receiving a glucose infusion survived for about 10 hours and all died of acute hepatic failure. Hepatic support systems can be accurately evaluated in this anhepatic rat model because of its uniformity. Sixty minutes of hepatic ischemia was able to be performed in rats with a transposed spleen for a portasystemic shunt and no complicated or technically involved procedure was required for the ischemic model. No rats died due to technical difficulties, suggesting the reliability and reproducibility of this ischemic model. An animal model resembling extrahepatic portal vein obstruction was also obtained by ligation of the portal vein; a simple maneuver which was able to produce collateral veins to the liver and cavernous transformation, as similarly seen in clinical patients with extrahepatic portal obstruction. Because these 3 animal models were so easily achieved in the rat, and since the changes in hepatic function and formation of the collaterals to the liver after portal vein occlusion are still poorly understood, this model should prove valuable for future study.

Evaluation of hemodynamics and hepatic mitochondrial function on extrahepatic portal obstruction in the rat

An animal model resembling clinical cases with extrahepatic portal vein obstruction was developed. The changes in hepatic mitochondrial function and the hepatic hemodynamics including hepatic regional blood flow, portal venous pressure, and portogram were evaluated to assess the effect of portal vein obstruction in the model. Portal vein ligation in this model was a simple and easy maneuver and could produce collateral veins to the liver--cavernomatous transformation--which were obviously seen in clinical patients with extrahepatic portal obstruction. Hepatic blood flow was significantly decreased until 5 days after portal vein ligation; however, hepatic blood flow was gradually increased and reached the normal value at 3 weeks after portal vein ligation due to the formation of the collateral veins to the liver. Respiratory parameters of mitochondria were gradually decreased and reached the lowest levels at 5 days after portal vein ligation, while they recovered to normal values in accordance with increasing hepatic blood flow at 3 weeks after portal vein ligation. In extrahepatic portal obstruction, although the liver is temporarily deteriorated by portal vein obstruction such as portal vein thrombosis, hepatic blood flow and the liver functions are to be normally improved with the formation of collateral veins to the liver.

Praziquantel in the treatment of hepatosplenic schistosomiasis: biochemical disease markers indicate deceleration of fibrogenesis and diminution of portal flow obstruction

Serological indicators for disease activity and portal vein obstruction and/or deviation were assessed in 23 patients with hepatosplenic schistosomiasis before, and up to 18 months after, praziquantel treatment, as well as in 25 matched local controls. Cessation of egg-induced immunopathology was reflected by the return to normal of serum procollagen-III-propeptide and neopterin concentrations. Reversibility of portal vein pathology was indicated by normal clearance of cholylglycine in cases without signs of decompensating portal hypertension. In most patients with a history of ascites and/or haemorrhage, serum cholylglycine concentration remained pathological. The results provide evidence that the fibrogenic process ceases after specific chemotherapy, and that portal vein pathology regresses in a substantial proportion of hepatosplenic schistosomiasis cases.

Mapping of Cavernous Vessels in the Liver in an Autopsy Case of Hepatocellular Carcinoma in Comparison with Imaging Figures

Cavernous vessels in the liver have been rarely described in the liver with hepatocellular carcinoma. We report the morphology and distribution of cavernous vessels in an autopsy liver of hepatocellular carcinoma, using a whole liver slice. In this case, antemortem angiography disclosed obstruction of portal veins at the hepatic hilus and portal trunk as well as many hepatopetal collaterals, mainly at the hepatic hilus. Tumor thrombi were diffusely distributed in the liver from the portal trunk to peripheral portal branches at autopsy. The cavernous vessels, which were positive for Factor VIII-related antigen, were also distributed throughout the liver from the hepatic hilus to the subcapsular regions, especially around the occluded portal veins by hepatocellular carcinoma, suggesting that these vessels were collaterals that developed as the result of portal obstruction. This study suggests that these vessels might be present from the hepatic hilus to the subcapsular regions, even if antemortem imaging techniques disclose collateral vessels only at the hepatic hilus.

Twenty-five-year experiences with esophageal transection for esophageal varices

Results of 287 transthoracoabdominal esophageal transections (Sugiura procedure), 125 transthoracic esophageal transections, 48 transabdominal esophageal transections, and 58 other nonshunting operations performed during the past 25 years were analyzed. Overall operative mortality rate was 5.0% (26/518); however, it was observed only in patients with liver cirrhosis (7.0%) and was higher in emergency cases (23.3%) and patients classified Child C (17.1%). Two hundred two patients died during the follow-up period, which lasted 24 years; 33 patients died of rebleeding, 89 of hepatic failure, 65 of hepatoma, and 35 of other causes. Cumulative survival rates of patients after non-shunting operations differed significantly according to the nature of the original diseases and the severity of liver damage. The cumulative survival rate at 10 years in patients with extrahepatic portal obstruction was 90.7%, 77.6% in idiopathic portal hypertension, and 33.0% in liver cirrhosis and at 20 years, 85.6%, 37.9%, and 8.1% respectively. The cumulative survival rate at 5 years in patients classified Child A was 88.7%, 77.7% in Child B, and 39.5% in Child C, and at 10 years, 73.4%, 45.3%, and 14.1%, respectively. Esophageal transection can be performed safely and is recommended in patients classified Child A or B. Patients in Child C should be treated by endoscopic sclerotherapy and other conservative measures.

H-type shunt with an autologous venous graft for treatment of portal hypertension in children.

From 1981 to 1987, 86 children aged 16 months to 16 years underwent a portosystemic shunt procedure using an autologous venous graft (internal jugular vein in 80 cases). Fifty-five mesocaval, 20 splenorenal, 4 portacaval, and 7 makeshift shunts were constructed. The indication for shunting was an extrahepatic portal obstruction in 59 cases, intrahepatic portal obstruction in 23 cases (including 6 cases of congenital hepatic fibrosis), and Budd-Chiari syndrome in 4 cases. One patient of the latter group died early from intractable ascites with a nonfunctioning shunt, and a second child died 2 months after operation from unknown reasons with a patent shunt. With a follow-up over 1 year for 58 of the 84 survivors, 78 successes and 6 failures were recorded according to the clinical outcome and the findings of ultrasonic and endoscopic examinations. Three of the six children with a failed shunt have been submitted to a second successful H-type shunt operation. No case of encephalopathy was recorded in this series. Thus, with an approximate success rate of 95%, the H-type shunt with a venous graft should be recommended for treatment of portal hypertension of extrahepatic origin, especially in young children.

Extrahepatic portal venous obstruction of different pathogenesis in pancreatic diseases: Reports of 4 autopsy cases with chronic pancreatitis and pancreatic carcinoma

Four autopsy cases of extrahepatic portal venous obstruction associated with pancreatic diseases, 1 case of pancreatitis and 3 cases of pancreatic carcinoma, are presented. The pathogenesis of portal obstruction was different in each case; old thrombosis with recanalization due to chronic pancreatitis with pseudocysts formation in 1 case, fresh thrombosis due to intraportal venous catheterization for pancreatic carcinoma in 1 case, fresh thrombosis probably due to pancreatitis accompanying pancreatic carcinoma in 1 case, and direct invasion of pancreatic carcinoma into the portal vein in the remaining 1 case. Morphologic evidence for portal hypertension was present in each case. In the pancreatitis case and one pancreatic carcinoma case with portal tumor invasion, both of which had chronic portal obstruction, there were many thin-walled vascular channels (cavernous transformation) around the occluded portal vein. Their endothelia were positive for factor VIII-related antigen and Ulex europaeus lectin I, implying that these vessels were hepatopetal blood vascular collaterals. It was shown that pancreatic diseases resulted in portal venous obstruction by several different mechanisms and chronic portal obstruction in pancreatic diseases led to the formation of hepatoperal blood vascular collaterals.