Asymptomatic extrahepatic portal obstruction without portal hypertensive findings detected in ultrasonic mass screening

BACKGROUND/AIMS

We report three adult cases of extrahepatic portal obstruction (EHPO) detected by ultrasonic (US) mass screening.

MATERIAL AND METHODS

All these cases were asymptomatic with no abnormalities on hematological or biochemical tests. Only indocynanine green clearance test revealed a slight abnormality. By imaging modalities, the portal trunk could not be visualized and cavernous transformation could be visualized.

RESULTS

There were no findings of portal hypertension, such as splenomegaly, esophageal varices and hepatofugal collaterals, in any of these cases.

CONCLUSIONS

As many EHPOs without symptoms can be detected on US mass survey, US is considered to be the best modality for screening for this disease.

Clinical evaluation of a monoclonal antibody to serum KM01 for the diagnosis of hepatocellular carcinoma

In order to evaluate a monoclonal antibody KM01 which was developed in mice immunized against a human colon carcinoma cell line, serum levels of KM01 and other tumor markers were studied in patients with both hepatocellular carcinoma and liver cirrhosis and in patients with liver cirrhosis alone. The KM01 levels in the sera of 50 patients with hepatocellular carcinoma plus liver cirrhosis and 50 patients with liver cirrhosis were measured using an enzyme immunoassay method and compared with various tumor markers including alpha-fetoprotein (AFP), DUPAN-2, and protein induced vitamin K absence or antagonist-II (PIVKA-II). The mean serum level (+/- S.D.) and sensitivity of KM01 in patients with hepatocellular carcinoma plus liver cirrhosis were 734 (+/- 716) units/ml and 64%, respectively, and they were significantly higher than those of liver cirrhosis patients (P < 0.001). Three out of 9 cases showing negative serum AFP levels had positive serum KM01 levels. Although the sensitivity of serum KM01 level for hepatocellular carcinoma was inferior to serum AFP and plasma PIVKA-II values, the sensitivity of a combination assay of serum KM01 or AFP was increased to 88%. Clinical data of the patients with markedly elevated serum KM01 levels (more than 1000 units/ml) were compared with patients with moderately elevated levels (530-1000 units/ml); serum bilirubin and alkaline-phosphatase were statistically higher in the former group (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic collagen synthesis and degradation during liver regeneration after partial hepatectomy

To elucidate hepatic collagen metabolism during liver regeneration after partial hepatectomy, we measured collagen content, collagen synthesis, and collagen-degrading enzyme activity in the remnant livers of rats 3, 5, 7, and 14 days after a partial hepatectomy of 68%. Hepatic collagen synthesis was significantly higher 3, 5, and 7 days after partial hepatectomy than it was in sham-operated control rats, but there was no such difference 14 days after surgery, the maximal hepatic collagen synthesis being observed 5 days after surgery. Although the collagen concentration in the remnant liver was similar to that in the control liver, the total collagen content of the remnant liver increased rapidly with liver regeneration until 7 days after partial hepatectomy. Hepatic collagenase activity was similar to the control; however, hepatic cathepsin B and cathepsin L activity and the intracellular degradation of newly synthesized collagen were markedly decreased 3, 5, and 7 days after partial hepatectomy compared with the controls. Hepatic collagen synthesis was significantly and inversely correlated with cathepsin L activity and with the intracellular degradation of newly synthesized collagen. These findings suggest that a combination of increased collagen synthesis and decreased intracellular collagen degradation contributes to the rapid supply of collagen that is observed during the early phase of liver regeneration.

Serum collagenase activity in chronic liver diseases

To examine whether serum collagenase activity reflects the amount of hepatic collagenase in the fibrotic liver, we measured serum collagenase activity in 67 patients with chronic liver disease and in 26 healthy controls. Collagenase activity in serum was measured after reactivation by denaturing and dissociating the inhibitors with 3 M KSCN and 1 mM aminophenylmercuric acetate. Serum collagenase activity was 35% lower than control in chronic persistent hepatitis, 48% lower in chronic active hepatitis, 56% lower in liver cirrhosis and 68% lower in hepatocellular carcinoma. To interpret this finding of low serum collagenase activity, we measured serum concentration of TIMP (Tissue Inhibitor of Metallo-Proteinases). Serum TIMP concentration was increased as liver disease developed, and it was inversely correlated with serum collagenase activity. These results suggest that in this assay condition serum collagenase activity is influenced by TIMP, and thus may not reflect the amount of hepatic collagenase in patients with chronic liver disease.

Serum type III procollagen peptide, type IV collagen 7S domain, central triple-helix of type IV collagen and tissue inhibitor of metalloproteinases in patients with chronic viral liver disease: relationship to liver histology

To assess the clinical value of serum biochemical markers, the aminoterminal peptide of type III procollagen, type IV collagen 7S domain, the central triple-helix of type IV collagen and tissue inhibitor of metalloproteinases, as a marker of hepatic fibrosis, we measured these four serum markers in 132 patients with chronic viral liver disease and compared these serum markers with liver histological findings. Serum levels of these markers increased closely with the progress of liver disease, and the abnormal percentages of type III procollagen peptide, type IV collagen 7S domain, central triple-helix of type IV collagen and tissue inhibitor of metalloproteinases in patients with cirrhosis were 97%, 95%, 83% and 48%, respectively. These four serum markers strongly correlated with the histological degree of periportal with or without bridging hepatocellular necrosis and of liver fibrosis and correlated weakly with the degree of intralobular degeneration and focal necrosis and the degree of portal inflammation. The correlation coefficients of serum type IV collagen 7S domain with periportal with or without bridging hepatocellular necrosis and with liver fibrosis were the highest among these four serum markers, suggesting that serum type IV collagen 7S domain is the most valuable diagnostic marker to assess the degree of liver fibrosis in chronic viral liver disease. When we assessed the ability of each serum marker to detect cirrhosis with a receiver operating curve, the best test was type IV collagen 7S domain, and the second best was type III procollagen peptide.(ABSTRACT TRUNCATED AT 250 WORDS)

Dynamics of hepatic collagen synthesis and intracellular degradation of newly synthesized collagen during chronic carbon tetrachloride-induced liver injury in rats

To clarify the significance of intracellular degradation of newly synthesized collagen during the progression of hepatic fibrosis, we measured the intracellular degradation of newly synthesized collagen at 2, 4 and 8 weeks after the administration of CCl4, together with the measurement of collagen synthesis and serum prolyl hydroxylase concentration. Hepatic collagen synthesis and serum prolyl hydroxylase concentration did not change until 4 weeks after the CCl4 administration, but was increased significantly at 8 weeks. Intracellular degradation of newly synthesized collagen was significantly increased at 2 weeks, was unchanged at 4 weeks, and was significantly decreased at 8 weeks compared with the individual control. The percentage of the intracellular degradation relative to the total amount of collagen synthesis did not change at 2 and 4 weeks, but was significantly decreased at 8 weeks, compared with the controls. These results suggest that the intracellular degradation system may prevent an accumulation of collagen at the early stage of hepatic injury, whereas at the stage of hepatic fibrosis, the combination of an increase in collagen synthesis and a reduction of intracellular degradation may lead to a rapid accumulation of collagen.

Serum collagenase activity reflects the amount of liver collagenase in chronic carbon tetrachloride-treated rats

To examine whether serum collagenase activity reflects the amount of collagenase activity in the fibrotic liver of rats, we simultaneously measured serum and hepatic collagenase activities in rats with carbon tetrachloride-induced liver injury. Serum collagenase was measured after reactivation by denaturing and dissociating the inhibitors with potassium thiocyanate and aminophenylmercuric acetate, while hepatic collagenase was measured after the removal of plasma protein and activation with aminophenylmercuric acetate. Serum and hepatic collagenase activities increased in the carbon tetrachloride-treated rats with the progression of liver fibrosis, and both activities of collagenase were closely correlated each other. These results suggest that serum collagenase activity measured in these assay conditions could be used as a noninvasive marker for hepatic collagenolysis in carbon tetrachloride-treated rats.

Combination therapy with transcatheter arterial embolization and percutaneous ethanol injection for advanced hepatocellular carcinoma

The effectiveness of transcatheter arterial embolization (TAE) combined with percutaneous ethanol injection (PEI) was investigated in 18 patients with advanced hepatocellular carcinoma (HCC), and compared with 18 patients with HCC treated by TAE therapy alone. In both groups, patients had multiple lesions or a single lesion larger than 3 cm. The pretreatment characteristics of the patients in the two groups showed that serum bilirubin in the TAE-PEI group was significantly higher than that in the TAE-only group, but that the patients in the two groups were comparable in all other respects. The cumulative survival rate of the TAE-PEI group estimated by the Kaplan-Meier method was 100% for 10 months, 82% for 20 months, 53% for 30 months and 18% for 40 months, whereas that of the TAE-only group was 75% for 10 months, 50% for 20 months, 30% for 30 months and 30% for 40 months. The survival rate in the TAE-PEI group was significantly higher than that in the TAE group. Moreover, the survival rate of patients whose main tumor was 4 cm or larger, was significantly higher in the TAE-PEI group than that in the TAE-only group. The average survival period of these patients in the TAE-PEI group was five times as long as that in the TAE-only group. The survival rate of Child's B and C patients in the TAE-PEI group was significantly higher than that in the TAE-only group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pathogenesis and treatment of hepatic encephalopathy]

Cirrhotic patients with hepatic encephalopathy show a variety of neuropsychiatric abnormalities. The pathogenesis appears to be ascribable to an increase in gut-derived neurotoxic substances and to functional alteration in inhibitory and excitatory neurotransmission in the brain. On the basis of the potential pathogenesis, therapies are designed by reducing the production and absorption of gut-derived neurotoxins and/or by modifying the balance of central neurotransmission. In this review, the current concept of the pathogenesis and treatment of hepatic encephalopathy is described.

[Toxic cirrhosis]

Carbon tetrachloride induces diffuse fatty degeneration and centrilobular necrosis in the liver and the severity of liver injury is roughly proportional to the dosage administered. Nonetheless, the incidence of cirrhosis by this agent is rare. Several drugs, including methyldopa, methotrexate, isoniazid and vitamin A, have occasionally been reported to cause chronic active hepatitis, fibrosis and cirrhosis. There is no question that continued administration of the drug in the presence of clinically apparent hepatitis can lead to chronic active hepatitis, fibrosis and cirrhosis. Early recognition that a therapeutic drug is the probable cause of liver injury, followed by prompt withdrawal of such a drug, generally suffices in the management of drug-induced chronic liver disease.

Serum tissue inhibitor of metalloproteinases in patients with chronic liver disease and with hepatocellular carcinoma

To examine the clinical significance of serum level of tissue inhibitor of metalloproteinases (TIMP) in chronic liver disease and in hepatocellular carcinoma, we measured serum TIMP concentration by a sandwich enzyme immunoassay in 79 patients with chronic liver disease and 49 patients with hepatocellular carcinoma. Serum TIMP concentration was 164 +/- 20 ng/ml in healthy controls, and was 10% higher than control in chronic persistent hepatitis, 36% higher in chronic active hepatitis, 62% higher in liver cirrhosis and 30% higher in primary biliary cirrhosis. Serum TIMP level was closely correlated with serum level of type IV collagen 75 domain and with the histological degree of liver fibrosis in chronic liver disease. Serum TIMP level in hepatocellular carcinoma was increased 2.3-fold compared with that in controls, and was significantly higher than in liver cirrhosis. Serum TIMP level increased with tumor size, and significantly correlated with serum alpha-fetoprotein level. Gel filtration on Sephadex G-75 showed that the TIMP in serum was present as an enzyme-complexed form. These results suggest that the measurement of serum TIMP concentration is useful in the clinical assessment of liver fibrosis in chronic liver disease and of the development of hepatocellular carcinoma.

Preventive effect of gomisin A, a lignan component of shizandra fruits, on acetaminophen-induced hepatotoxicity in rats

The preventive effect of gomisin A, a lignan component of shizandra fruits, on acetaminophen-induced hepatotoxicity in rats was examined by histological and biochemical analysis. Acetaminophen at a dose of 750 mg/kg was administered to male Wistar rats with or without pretreatment with 50 mg/kg of gomisin A. Gomisin A inhibited not only the elevation of serum aminotransferase activity and hepatic lipoperoxides content, characteristic of acetaminophen administration, but also the appearance of histological changes such as degeneration and necrosis of hepatocytes. However, gomisin A did not affect the decrease in liver glutathione content. These results suggest that gomisin A protects the liver from injury after administration of acetaminophen through the suppression of lipid peroxidation.

Serum collagenase activity in patients with chronic liver disease

To examine the clinical significance of serum collagenase activity in chronic liver disease, serum collagenase activity was determined in 50 patients with chronic liver disease and in 24 healthy controls. Collagenase activity was measured after reactivation by denaturing and dissociating the inhibitors with potassium thiocyanate and aminophenylmercuric acetate. In patients with chronic persistent hepatitis, serum collagenase activity was 37% lower than controls, 50% lower in those with chronic active hepatitis, 66% lower in those with cirrhosis and 68% lower in those with hepatocellular carcinoma. Serum collagenase activity was significantly and inversely correlated with serum levels of the aminoterminal propeptide of type III procollagen and type IV collagen 7S domain, indicating that serum collagenase activity decreased as liver active fibrogenesis and/or fibrosis occurred. In contrast, serum levels of the metalloproteinase inhibitor was 30% higher than controls in patients with chronic active hepatitis, 50% higher in those with cirrhosis and 80% higher in those with hepatocellular carcinoma and was inversely correlated with serum collagenase activity. These results suggest that in this assay condition serum collagenase activity is influenced by the metallo-proteinase tissue inhibitor and thus does not reflect the amount of collagenase in the fibrotic liver.

Serum amino acid levels and hepatic protein synthesis during liver regeneration after partial hepatectomy in rats

The time courses of changes in serum concentrations of free amino acids and in hepatic protein synthesis during liver regeneration after partial hepatectomy were studied in rats. Hepatic protein synthesis was significantly higher 3, 5 and 7 days after partial hepatectomy than it was in sham-operated control rats, but there was no such difference 14 days after surgery. Serum total amino acid level was significantly higher in partially-hepatectomized rats than in control rats 3 days after surgery, and thereafter decreased slowly. By 7 days after surgery there was no significant difference between the two groups. Serum concentrations of threonine, serine, proline, histidine, tyrosine, methionine, ornithine and citrulline were significantly higher than in the control group 3 days after partial hepatectomy, and the concentrations of proline, histidine, tyrosine, methionine and ornithine were still high 5 days after surgery. In contrast, concentrations of branched-chain amino acids did not change.

Collagenolytic cathepsin B and L activity in experimental fibrotic liver and human liver

To clarify the role of individual collagenolytic cathepsin in hepatic collagen degradation, cathepsin B and L activities were determined in normal and CCl4-induced fibrotic liver, together with non-collagenolytic cathepsin H. Cathepsin B and L activities increased 1.9- and 2.0- fold, respectively, in the fibrotic liver as compared with the normal liver, and were significantly correlated with hepatic hydroxyproline levels. By contrast, cathepsin H activity was not altered in fibrotic rats. Similar results were also obtained from autopsied human livers. These results suggest that cathepsin B and L are similarly induced by hepatic collagen levels and are implicated in degrading collagens, especially soluble collagen.

Serum lysyl oxidase activity in chronic liver disease in comparison with serum levels of prolyl hydroxylase and laminin

Lysyl oxidase was partially purified from serum by a diethylaminoethyl batch procedure in the presence of 6 mol/L urea and dialyzed against 3 mol/L KSCN. Using this method, we determined serum lysyl oxidase activity in 52 patients with liver disease and in 14 healthy controls, and we examined usefulness of serum lysyl oxidase in assessing liver fibrogenesis. For this purpose, serum lysyl oxidase activity in chronic liver disease was compared with serum levels of prolyl hydroxylase and laminin P1. As compared with controls, serum lysyl oxidase activity increased 1.6-fold in chronic persistent hepatitis, 4.4-fold in chronic active hepatitis and 11.8-fold in cirrhosis, indicating an increase in concert with the development of liver fibrosis. In hepatocellular carcinoma, the serum activity, although significantly increased, was lower than that in cirrhosis. Serum prolyl hydroxylase was significantly increased in chronic active hepatitis, in liver cirrhosis and in hepatocellular carcinoma. Serum laminin P1 was significantly increased in chronic active hepatitis, in cirrhosis and in hepatocellular carcinoma. Serum lysyl oxidase activity did not correlate significantly with serum levels of prolyl hydroxylase and laminin P1 in any subject or in any subgroup. The magnitude of the increase and the abnormal percentage of serum lysyl oxidase activity were larger than those for serum prolyl hydroxylase and laminin P1. These results suggest that serum lysyl oxidase activity is a more sensitive indicator of liver fibrosis than serum prolyl hydroxylase and laminin P1.

Hepatic collagen synthesis in patients with alcoholic and nonalcoholic liver disease

To examine the synthesis of hepatic collagen in patients with alcoholic and nonalcoholic liver disease, liver biopsy specimens were incubated in vitro with 14C-proline, and the radioactivity of the newly synthesized protein-bound 14C-hydroxyproline was measured. Mean hepatic collagen synthesis was 0.82 +/- 0.19 pmole of 14C-hydroxyproline/g liver/2 h in control subjects without histological liver fibrosis. Hepatic collagen synthesis was increased in patients with alcoholic and nonalcoholic liver diseases, especially in those with alcoholic fibrosis, alcoholic cirrhosis and chronic active hepatitis. The raised collagen synthesis in alcoholic liver disease rapidly decreased after withdrawal of alcohol. When alcoholic liver disease were compared with nonalcoholic liver disease, there was no significant difference in hepatic collagen synthesis.

Lectin-reactive patterns of markedly elevated serum alpha-fetoprotein in patients with chronic active hepatitis

Four cases of chronic hepatitis associated with high serum levels of alpha-fetoprotein (AFP) without hepatocellular carcinoma are reported. All showed transient elevations of serum AFP, with peak levels of 13,500, 8,000, 4,450, and 3,000 ng/ml shortly after aggravation resulting from liver function tests. Liver biopsies revealed severe parenchymal damage in all the cases with piece-meal necrosis, bridging necrosis or bridging fibrosis. In two of four cases, there was a lobular distortion. AFP stain by an immunoperoxidase method showed a positive result in surviving hepatocytes. Lectin affinity electrophoresis of AFP in the four cases, together with an additional 12 patients with chronic hepatitis and cirrhosis and 44 patients with hepatocellular carcinoma, all having AFP levels above 1,000 ng/ml, revealed that the chronic hepatitis patients had a benign pattern of AFP bands, in contrast with the pattern of hepatocellular carcinoma with increased proportions of lentil lectin-reactive AFP-L3 and/or erythroagglutinating phytohemagglutinin-reactive AFP-P4, indicating that the analysis of lectin reactivity of AFP has a great value in differentiating the benign and malignant conditions with increased serum levels of AFP above 1,000 ng/ml.

Increase in lipoperoxides and prolyl hydroxylase activity in rat liver following chronic ethanol feeding

The effect of lipid peroxidation on hepatic collagen synthesis was investigated in male Wistar strain rats after 7 weeks of ethanol feeding. Compared with control rats, the ethanol-fed rats had a significantly higher lipoperoxide content and a significantly lower reduced glutathione content al all times following ethanol treatment. Except for the earliest time (2 days), hepatic prolyl hydroxylase activity was also significantly increased and finally reached up to 214% of the control level. Hepatic hydroxyproline content was slightly increased, but not statistically significant. The lipoperoxides content was significantly correlated with prolyl hydroxylase activity and inversely correlated with reduced glutathione content. These findings were also confirmed in ethanol-pyrazole-treated rats. These results suggest that elevated lipoperoxides mediate an acceleration of collagen synthesis, even at an early stage, in ethanol-induced hepatic injury.