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A possible hepatotoxicity of cigarette smoke has been recently suggested by epidemiological and experimental studies. Our aim was to study the possible relationships between smoking and liver fibrosis and activity in patients with chronic hepatitis C. A cross-sectional study was performed in a group of 310 patients with chronic hepatitis C consecutively hospitalized for their first liver biopsy. The relationships between age, gender, alcohol consumption, route of contamination, tobacco consumption, and Knodell fibrosis and activity scores were examined in univariate, age-adjusted, and multivariate analyses. One hundred and seventy-six patients (57%) were current smokers. Smokers were younger (P <.001), more often of male gender (P =.001), more often alcohol consumers (P =.001), and more often had a history of intravenous drug use (P =.0001) than never smokers. Smoking was related to increased fibrosis and activity scores in age-adjusted (P =.009 and P =.005, respectively) and multivariate analyses (P =.03 and P =.04, respectively). Smoking increases the severity of hepatic lesions in patients with chronic hepatitis C.

According to a recent hypothesis, venous thrombosis results from the concurrence of several factors. This hypothesis was assessed in patients with portal or hepatic venous thrombosis by simultaneously investigating most of the currently identified prothrombotic disorders, local precipitating factors, and other risk factors such as oral contraceptive use. Patients with a tumorous obstruction and patients with cirrhosis with portal vein thrombosis were excluded. The prothrombotic disorders that were investigated included classical and occult myeloproliferative disorders; antiphospholipid syndrome; protein C; protein S and antithrombin deficiency; factor V Leiden; factor II; and methylene-tetrahydrofolate-reductase gene mutations. We found 1 or several prothrombotic disorders and a local precipitating factor in 26 and 10 of the 36 patients with portal vein thrombosis, respectively; and in 28 and none of the 32 patients with hepatic vein thrombosis, respectively. We found a combination of prothrombotic disorders in 5 and 9 patients with portal and hepatic vein thrombosis, respectively, whereas such a combination is expected in less than 1% of asymptomatic subjects. Of the 10 patients with a local precipitating factor, 8 had a prothrombotic disorder. Of the 13 patients who use oral contraceptives, 10 had a prothrombotic disorder. We conclude that portal or hepatic venous thrombosis should be regarded as an index for 1 or several prothrombotic disorders, whether or not local precipitating factors or oral contraceptive use are found. Concurrence of prothrombotic disorders is more common than expected. Extensive investigation of prothrombotic disorders and anticoagulation should be considered in patients with portal or hepatic venous thrombosis.

The aim of this study was to assess the factors, including surgical portosystemic shunts, which affect survival in adults with Budd-Chiari syndrome. Multivariate retrospective analysis was performed using characteristics recorded at the time of diagnosis in 120 patients admitted from 1970 to 1992, of whom 82 were treated with surgical portosystemic shunts and 38 received only medical therapy. The 1-, 5-, and 10-year survival rates were 77 +/- 4%, 64 +/- 5%, and 57 +/- 6%, respectively. Survival was significantly better in the subgroup of patients diagnosed after versus before 1985. In both subgroups, and in patients with, as well as in patients without surgical shunts, 4 factors were found to be inversely and independently related to survival: age, response of ascites to diuretics, Pugh score, and serum creatinine. In patients diagnosed since 1985, an index combining these 4 factors allowed to differentiate patients with a good outcome (5-year survival 95%) from those with a poor outcome (5-year survival 62%; P <.05). There was no statistically significant and independent influence of surgical portosystemic shunts on survival. In conclusion, age, severity of liver failure, and presence of refractory ascites are the main prognostic factors in Budd-Chiari syndrome. Increased survival in recent years is consistent with improved management of hypercoagulable states as well as improved general care. It is uncertain whether surgical portosystemic shunting favorably modifies survival. Therefore, we recommend that surgical shunting should be restricted to management of refractory ascites or variceal bleeding in patients with otherwise good prognostic factors.

The aim of this study was to assess the influence of human immunodeficiency virus (HIV) infection on chronic hepatitis B. In a series of 132 (65 anti-HIV positive) homosexual non-drug addicted men with chronic hepatitis B, the liver function was assessed with biochemical tests; the degree of hepatitis B virus (HBV) replication was assessed with serum HBV DNA level and with immunoperoxidase staining of hepatitis B core (HBc) antigen on liver specimens; and the severity of liver lesions was assessed with an histology activity index. Anti-HIV-positive and anti-HIV-negative patients were not different for serum aspartate transaminase activity, bilirubin, prothrombin, and histology activity index. Anti-HIV-positive patients had lower serum alanine transaminase activity levels (P =.0001), lower serum albumin levels (P =.0009), and higher serum HBV DNA levels (P =.01). There was a higher prevalence of cirrhosis in anti-HIV-positive patients (P =.04). In homosexual men with chronic hepatitis B, HIV infection is associated with a higher level of HBV replication and a higher risk for cirrhosis without increased liver necrotico-inflammatory process.

It has been shown that certain patients with cirrhosis have asymptomatic cardiac abnormalities that have not yet been explained. Thus, cardiac troponin I, a specific marker of myocardial injury, has been measured in patients with cirrhosis without previous cardiac disease. Thirty-two consecutive patients (age 49 +/- 11) with cirrhosis and normal ECG were selected, 22 of which were alcoholic. Hemodynamic investigations were performed. Left ventricular function and mass were evaluated by echocardiography. Serum creatine kinase MB mass, myoglobin, and cardiac troponin I concentrations were measured. Cardiac troponin I concentrations were elevated in 10 patients (32%) (range 0.06-0.25 microg/L) whereas creatine kinase MB mass and myoglobin were normal in all patients. Abnormal troponin I values were not related to the severity of cirrhosis, to the degree of portal hypertension, or to other hemodynamic values. In contrast, elevated serum cardiac troponin I concentrations were related to a decreased stroke-volume index (P <. 05) and a decreased left ventricular mass (P <.05). These results show a high prevalence of slightly elevated serum cardiac troponin I in patients with cirrhosis, especially in those with alcoholic cirrhosis. Elevated troponin I is associated with subclinical left ventricular myocardial damage. These findings may be linked to a lack of left ventricular adaptation in certain patients with cirrhosis and alcoholic cardiomyopathy.

The role of alcohol intake in the occurrence of severe liver disease in chronic hepatitis C virus (HCV) carriers is still debated. A cross-sectional study has been conducted in 233 chronic hepatitis C virus carriers. Weekly self-reported alcohol consumption (SRAC) was evaluated, serum HCV RNA levels were measured by a branched DNA technique (Quantiplex 2.0) and HCV genotypes were determined. A liver biopsy was performed simultaneously and liver lesions were graded with the Knodell histological activity index. Data were examined by uni- and multivariate analyses. Alcohol consumption was relatively low (< 140 g/per week in 193/233 patients [80%]). We found a highly significant correlation between SRAC and serum HCV RNA levels (r = .26, P = .001). Fibrosis was significantly correlated with age and alcohol consumption. These results suggest that in HCV carriers, alcohol consumption, even with low alcohol intake, increases viremia and hepatic fibrosis. Chronic HCV carriers should be advised to avoid regular alcohol intake.

Treatment of patients with chronic hepatitis C has had limited success because of relapses and nonresponse to interferon alfa therapy (currently the only established therapeutic agent). A retrospective study was done to determine the efficacy of re-treatment with interferon and the predictors of response in patients who failed to achieve sustained response after one standard course of interferon therapy (3 million units three times a week for 24 weeks). One hundred and eleven patients (47 relapsers and 64 nonresponders), mean age 45 years, were included in the study. Eighteen relapsers and 13 nonresponders received a higher dose (5 MU), and 11 relapsers and 6 nonresponders received a longer duration (48 weeks) of interferon therapy. The remaining patients received the same regimen as the first treatment. Eighty-one percent and 23% of relapsers and nonresponders, respectively, had an end-of-treatment response, and 19% and 3% of the corresponding patient groups had a sustained response to re-treatment. Two patients with breakthrough during their first treatment were the only nonresponders with sustained response after re-treatment. Sustained response was observed only in patients who received an increased dose or duration of interferon therapy. No predictor of sustained response was found. In conclusion, sustained response to re-treatment with interferon was only observed with augmentation of dose or duration of therapy in some relapsers and patients who had breakthrough. Established predictors of response to interferon in naive patients, in particular serum hepatitis C virus RNA and genotype, were not associated with sustained response to re-treatment.

An important group of patients with chronic hepatitis C have normal serum alanine aminotransferase (ALT) levels despite having hepatitis C virus (HCV) RNA detectable in serum. These patients are typically identified after donating blood and being found to be positive for antibody to HCV (anti-HCV). A strict definition of this patient population is needed, which should include presence of anti-HCV, HCV RNA detectable by polymerase chain reaction (PCR), and persistently normal ALT levels. These patients are usually asymptomatic, but almost all have histological evidence of chronic hepatitis on liver biopsy. The liver histological lesions are generally mild, and cirrhosis is rare. The long-term outcome of this group of patients with chronic HCV infection is not known, but the prognosis is probably good. In small, uncontrolled trials of alpha interferon in this group of patients, end-of-treatment virological responses occurred in approximately 50% and sustained responses 6 to 12 months afterwards in 20%. These rates of response are not very different from those reported in patients with abnormal ALT levels. Importantly, in most studies, serum ALT levels became abnormal during therapy in approximately half of patients, and levels remained abnormal in a proportion after therapy. These findings suggest that alpha interferon therapy is not usually beneficial and may be harmful in patients with chronic hepatitis C who have normal ALT levels, perhaps as a result of the immunomodulatory actions of alpha interferon that may alter the balance of host immune reactions and viral replication, which seem to be responsible for the liver injury in chronic hepatitis C.

In contrast with the well-recognized membranous obstruction of the inferior vena cava, short-length hepatic vein stenoses are not well-recognized causes of hepatic venous outflow block. The aim of this study was to ascertain the prevalence, causes, manifestations, and outcome of short-length hepatic vein stenoses. We performed a retrospective study of patients with short-length hepatic vein stenosis among 86 patients with hepatic venous outflow block who were seen between 1970 and 1992. There were 25 patients with short-length hepatic vein stenosis. A thrombogenic condition was identified in 14 patients (56%). The lesions of the accompanying hepatic veins in these patients were variable (short-length stenoses, thromboses, or nonspecific changes) and similar to that seen in patients without short-length hepatic vein stenosis. In 3 necropsied cases, the venous lesions were suggestive of fibrous sequela of prior thromboses. In patients with short-length hepatic vein stenosis, splenomegaly (28% vs. 55%, P < .05) and hypersplenism were significantly less common; serum transaminase (P < .001) and creatinine levels (P < .02) were lower, prothrombin was higher (P < .001), and 5-year survival was significantly better (Kaplan-Meier estimates: 80% vs. 50%, P < .05). In patients with hepatic venous outflow block, short-length hepatic vein stenosis is a common lesion that appears to be the sequela of localized thrombosis. Long-term anticoagulation and percutaneous angioplasty (with or without stenting) are potentially applicable in these lesions. The long-term results of these treatments merit further evaluation.

Formaldehyde may induce severe lesions of intrahepatic and extrahepatic bile ducts. The purpose of this study was to examine in vivo the functional consequences of an alteration of the biliary epithelium induced by a retrograde intrabiliary injection of formaldehyde in rats. After basal bile collection, a 10% formaldehyde solution was injected into the biliary tree of anesthetized rats, and the cannula was occluded for 30 minutes. Choleresis was then reestablished, and bile flow, bile acid, and bicarbonate secretion were measured both spontaneously and during ursodeoxycholate infusions. Formaldehyde injections induced a significant increase in bile flow and a marked inhibition of ursodeoxycholate-induced increase in biliary bicarbonate concentration and secretion. Biliary glucose secretion, which is normally very low, was increased about 20-fold in animals injected with formaldehyde. Histological and ultrastructural examination of the liver showed alterations of biliary epithelial cells, whereas hepatocytes, bile canaliculi, and canalicular tight junctions remained normal. Hepatocytic excretory function, as assessed by biliary secretion of bile acids, was not affected. It was concluded that short-term formaldehyde intrabiliary injections cause an inhibition of ursodeoxycholate-induced hypersecretion of bicarbonate, an increase in biliary glucose secretion, and selective structural alterations of biliary epithelial cells. These results suggest that formaldehyde retrograde biliary injection may be a useful model to study alterations of biliary epithelial function in vivo.

Disruption of the murine mdr2 (multidrug-resistance) gene, which encodes a phosphatidylcholine flippase, leads to a hepatic disorder because of loss of biliary phospholipid secretion. Among the hereditary human cholestasis, a subtype of progressive familial intrahepatic cholestasis with high gamma-glutamyltranspeptidase (GGT) serum activity shares histological, biochemical, and genetic features with mice lacking mdr2 gene expression (mdr2 -/- mice). No MDR3 (human mdr2 homolog) messenger RNA (mRNA) was detected by Northern blotting in the liver of a patient suffering from this form of PFIC, and the biliary phospholipid level in a second patient was substantially decreased. Thus, the absence of the MDR3 P-glycoprotein may be responsible for this type of PFIC, which, as in the murine model, may be due to a toxic effect of bile acids on the biliary epithelium in absence of biliary phospholipids.

Isoniazid and pyrazinamide are well-known hepatotoxic drugs, often used in combination. The aim of this study was to assess the prognostic influence of pyrazinamide on the outcome of fulminant or subfulminant liver failure caused by antituberculous therapy. Eighteen patients with fulminant or subfulminant liver failure due to antituberculous therapy were studied. Nine patients received isoniazid and rifampicin without pyrazinamide (group 1), and nine patients received isoniazid and rifampicin together with pyrazinamide (group 2). The severity of fulminant and subfulminant liver failure, as judged by the prevalence of coma and the lowest level of factor V, was similar in the two groups. Spontaneous survival was greater in group 1 (eight of nine) than in group 2 (two of nine) (P < .02). The authors conclude that pyrazinamide co-administration was associated with an increased mortality in patients with fulminant or subfulminant hepatitis occurring during antituberculous therapy. In these patients, pyrazinamide administration and an interval of more than 15 days between the onset of antituberculous treatment and jaundice, combined with grade III encephalopathy and factor V below 20%, predicted death without liver transplantation.

The objective of this study was to evaluate the role of hepatitis B virus (HBV) precore mutations in patients with anti-HBe-positive chronic hepatitis B with or without previous known HBe antigen (HBeAg) viremic phase, and to assess the potential implication of precore mutants in HBeAg-negative reactivation after loss of HBeAg. Nineteen patients were studied: 7 had a previous HBeAg-positive phase and had spontaneous or therapeutically induced loss of HBeAg (group A); 12 had no previous HBeAg-positive phase (group B). Direct sequencing of PCR products was performed on serum collected during the anti-HBe-positive phase in the two groups. In group A, precore sequencing showed that 5 patients were infected by wild-type virus, 1 patient was infected with a precore mutant, and 1 patient was found to be infected by a mixture of wild-type and precore mutant viruses. In group B, precore sequencing showed that only 1 patient was infected with wild-type virus and that 11 were infected with precore mutants. In a few patients, the presence of HBeAg within immune complexes may explain HBeAg negativity. In conclusion, our results show that, in patients with anti-HBe-positive chronic hepatitis B: (1) precore mutations creating a stop codon are more frequently found in those without known previous HBeAg positivity; (2) after loss of HBeAg, the patients who have anti-HBe-positive reactivation are infected by wild-type virus, which suggests that reactivation is not related to precore mutations; (3) HBeAg negativity may be caused by immune complexes formation.

Intraportal lymphoid nodules have been observed in liver biopsy specimens from patients with autoimmune liver disease and chronic active hepatitis C. They are characterized by a nodular lymphocyte aggregate with a germinal center. The purpose of this in situ immunophenotyping study was to determine immunohistochemically the phenotype of immunocompetent cells in and around intraportal lymphoid nodules in patients with chronic hepatitis C. For comparison, we also examined lymphoid nodules in patients with autoimmune liver disease. Liver biopsy specimens from 13 unselected patients with CAH and hepatitis C antibodies and from 7 unselected patients with autoimmune liver disease seen during the same period were studied. Sections of snap-frozen specimens were immunostained with monoclonal antibodies directed against different subsets of T cells, B cells, follicular dendritic cells and macrophages. Intraportal lymphoid nodules were observed in 11 of 13 patients with chronic hepatitis C. They appeared as lymphoid follicles with activated B cells in germinal centers surrounded by a follicular dendritic cell network. A mantle zone of B cells was present around the aggregate of activated B cells. A T-cell zone comprising CD4-positive helper T cells, CD8-positive suppressor/cytotoxic T cells and a few CD25-positive activated T cells expressing interleukin-2 receptor was seen at the periphery of the nodules. Human leukocyte antigen DR was expressed by B cells and by T cells, indicating that T cells were activated. The immunocompetent cells observed in piecemeal necrosis were predominantly CD4 helper T cells, whereas those seen in the lobule were predominantly CD8 suppressor/cytotoxic T cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Portal pressure and portal-systemic collateral circulation after orthotopic liver transplantation have not been investigated. We studied systemic and splanchnic hemodynamics in 17 patients with cirrhosis before and 205 +/- 146 days after orthotopic liver transplantation. Among the 17 orthotopic liver transplantation patients, 12 had undergone hemodynamic study in the 6 mo before orthotopic liver transplantation. Controls were 50 patients with normal liver architecture. Cardiac index remained elevated in orthotopic liver transplantation patients compared with controls (3.6 +/- 0.9 vs 3.1 +/- 0.4 L/min.m2; p < 0.05). Azygos blood flow, which was elevated before orthotopic liver transplantation (585 +/- 402 ml/min), remained elevated after orthotopic liver transplantation (553 +/- 343 ml/min). In transplant patients, hepatic blood flow was higher than it was in controls (2.26 +/- 0.86 vs. 1.38 +/- 0.57 L/min; p < 0.05). Elevated hepatic blood flow correlated with cardiac index (r = 0.647, p < 0.025). In patients with normal graft function, hepatic venous pressure gradient was normal (2 +/- 1 mm Hg). In a patient with acute rejection, a sharp elevation in the hepatic venous pressure gradient was observed; it returned to normal 45 days after treatment. We conclude that despite normal portal pressure, portal-systemic collateral blood flow remains elevated after orthotopic liver transplantation. Possibly because of persistent collateral circulation, which may keep portal tributary blood flow elevated, hepatic blood flow is increased after orthotopic liver transplantation. Elevated splanchnic blood flow, in turn, contributes to the high cardiac index in liver recipients. Finally, a sharp elevation in portal pressure, which may be observed during acute rejection and subsides after treatment, merits further study.

The objective was to determine the proportion of patients with chronic hepatitis B in whom hepatitis B virus DNA is demonstrated by polymerase chain reaction after HBeAg to anti-HBe or HBsAg to anti-HBs spontaneous or therapeutically induced seroconversion. Polymerase chain reaction was performed on serum 6 and 12 mo after HBeAg to anti-HBe seroconversion in 12 patients and 2, 6 and 12 mo after HBsAg to anti-HBs seroconversion in 13 patients. Polymerase chain reaction was performed on liver tissue after HBeAg to anti-HBe seroconversion in five patients and after HBsAg to anti-HBs seroconversion in one patient. Serum HBV DNA was demonstrated by polymerase chain reaction in 83% of patients 6 or 12 mo after HBeAg to anti-HBe seroconversion and in 58%, 31% and 15% of patients at 2, 6 and 12 mo, respectively, after HBsAg to anti-HBs seroconversion. Liver HBV DNA was demonstrated by polymerase chain reaction in all patients tested. Our results show that (a) a reduced level of hepatitis B virus replication persists in most of the patients after HBeAg to anti-HBe seroconversion and might be predictive of reactivation, and (b) in contrast, hepatitis B virus replication progressively disappears in most of the patients after HBsAg to anti-HBs seroconversion.

It has been proposed that a microtubule-dependent transport of vesicles derived from the Golgi apparatus may play a role in biliary secretion of bile salts and other cholephilic anions. To test this hypothesis, we examined the influence of colchicine and vinblastine, two microtubule inhibitors, on diethylmaleate-induced bile flow and on the biliary secretion of diethylmaleate, an organic anion whose glutathione conjugates may be secreted into bile through the Golgi apparatus and Golgi-derived vesicles. Rats were pretreated with colchicine or vinblastine, and diethylmaleate was injected intraperitoneally at doses of 28 to 400 mumol/100 gm body wt. Basal bile flow was unaffected by colchicine or vinblastine. In contrast, diethylmaleate-induced bile flow and the secretion into bile of diethylmaleate conjugates (estimated by the cation-anion gap in bile) were significantly lower in colchicine-treated and vinblastine-treated animals than in controls. Diethylmaleate-induced bile flow was reduced in proportion to diethylmaleate conjugate secretion. A linear relationship was seen between bile flow and biliary output of diethylmaleate conjugates: this relationship was similar in colchicine-treated or vinblastine-treated animals and in controls. At electron microscopy, diethylmaleate had induced distension of the Golgi saccules of the hepatocytes. In conclusion, colchicine and vinblastine inhibited the secretion into bile of diethylmaleate conjugates and diethylmaleate-induced bile flow. These results support the view that microtubule-dependent transport of Golgi-derived vesicles is involved in the biliary secretion of diethylmaleate and, perhaps, other cholephilic organic anions.

Membranous obstruction of the inferior vena cava has been reported mainly in South Africa, Japan, and India; in 20-40% of patients the disease is complicated by hepatocellular carcinoma. We report a case of membranous obstruction of the inferior vena cava with hepatocellular carcinoma in a 43-year-old Caribbean man of Indian origin. The Caribbean islands may constitute another geographical area where the population is at risk for the development of membranous obstruction of the inferior vena cava and subsequent hepatocellular carcinoma.

Hepatic artery and portal vein blood flows were assessed separately in anesthetized rats using radiolabeled taurocholate. The ratio of portal vein blood flow to total hepatic blood flow was calculated from measurements of taurocholate concentrations of portal vein, hepatic artery and hepatic vein, and of taurocholate hepatic extraction ratio. Animals were administered [14C]taurocholate intraperitoneally as a label of the taurocholate pool 24 hr before the experiments. In steady-state conditions, serum [14C]taurocholate activities were used as an index of taurocholate relative concentration and the hepatic extraction ratio of taurocholate was estimated using [3H]taurocholate infused into the systemic blood stream. Total hepatic blood flow was estimated by the Fick's principle using indocyanine green. The mean hepatic blood flow was 13.9 ml X min-1 (S.E. 1.9), and the mean ratio of portal blood flow to hepatic blood flow was 72.2% (S.E. 6.7). It is concluded that taurocholate may be used to assess separately portal venous and hepatic arterial blood flow in the rat.

Taurocholate (TC) uptake by adult rat hepatocytes co-cultured with other rat liver epithelial cells (RLEC) was studied comparatively to hepatocytes in primary culture. Cells were cultured on Petri dishes for desired times prior to measuring their ability to transport TC. TC uptake was linear for 150 sec in both culture conditions. In hepatocytes cultured alone, the initial rate of TC uptake at an extracellular concentration of 100 microM was 0.19 +/- 0.02 nmole per min per 10(6) cells after 48 hr of culture and decreased by 75% after 4 to 6 days. In hepatocytes co-cultured with RLEC, the rate of uptake at 48 hr (0.31 +/- 0.01 nmole per min per 10(6) cells) was significantly higher than in hepatocytes cultured alone (p less than 0.01); in addition, TC uptake remained stable at an average rate of 0.17 +/- 0.01 nmole per min per 10(6) cells for up to 56 days. No detectable uptake was found in RLEC cultured alone. TC uptake exhibited both saturable (Vmax = 0.30 +/- 0.03 nmole per min per 10(6) cells and Km = 42.6 +/- 4.4 microM) and nonsaturable components. These kinetic parameters were similar to those previously reported in isolated hepatocytes and in short-term cultured hepatocytes. TC uptake exhibited sodium dependence and was significantly reduced when extracellular sodium was replaced by lithium and sucrose, or in the presence of 1 mM ouabain. After 18 days of co-culture, TC uptake had qualitatively the same characteristics as at 48 hr, with a saturable and a nonsaturable component.(ABSTRACT TRUNCATED AT 250 WORDS)

A double-blind randomized, multicenter study was carried out to determine the efficacy and safety of ursodeoxycholic acid (UDCA) at 4 doses of 2.1 to 16.2 mg X kg-1 X day-1, and chenodeoxycholic acid (CDCA) at the dose of 16.9 mg X kg-1 X day-1, in 197 patients treated for up to 1 year for radiolucent gallstones in functioning (opacified) gallbladders. There was confirmed complete dissolution in 5.9% of patients receiving UDCA at the dose of 2.1 mg X kg-1 X day-1, 18.9% in those receiving 4.2, 28.9% in those receiving 8.4, 14.6% in those receiving 16.2, and 20.0% in patients receiving CDCA. Partial (over 50%) or complete dissolution occurred in 29.4% of patients receiving 2.1 mg X kg-1 X day-1 of UDCA, 37.8% of those receiving 4.2, 55.2% in those receiving 8.4, 48.7% in those receiving 16.2, and 50.0% in patients receiving CDCA. Complete dissolution occurred significantly more frequently in small (less than 5 mm in diameter) than in large (5 to 15 and more than 15 mm) stones. There was no significant influence of treatment on serum cholesterol and triglycerides in any of the groups. Serum aminotransferases remained normal (or lower than twice the upper normal limit) in all patients treated with UDCA. Diarrhea leading to cessation of treatment occurred in 5% of patients receiving UDCA, but was significantly less frequent than in those receiving CDCA. These results confirm that, within a 1-year period, UDCA is equally effective and induces diarrhea less frequently than CDCA, with an optimal dose (8 mg X kg-1 X day-1) approximately twice lower than that of CDCA.

The effect of acute metabolic or respiratory acid-base disturbances on biliary bicarbonate secretion was examined in bile fistula rats. Animals were infused with ursodeoxycholate at a rate that stimulates bicarbonate secretion (1 mumole . min-1 X 100 gm-1), in control conditions and during acute acid-base disturbances. Metabolic acidosis or alkalosis were induced by HCl or NaHCO3 infusions, and respiratory acidosis or alkalosis were created respectively by adding CO2 to the inspired gas or by hyperventilation in artificially ventilated animals. Biliary bicarbonate concentration was always higher than plasma bicarbonate concentration. During metabolic disturbances, changing the plasma bicarbonate concentration from 9.2 to 30.2 mM stimulated biliary bicarbonate secretion by 113%. During respiratory disturbances, changing the plasma PCO2 from 25.5 to 59.8 mm Hg also increased biliary bicarbonate secretion by 89%. Biliary bicarbonate output was thus independent of plasma pH. When all animals were considered, bile flow was positively correlated with biliary bicarbonate concentration (r = 0.71, p less than 0.001). Acetazolamide significantly decreased ursodeoxycholate-induced bile flow and bicarbonate secretion by 20 and 22%, respectively. These results support the hypothesis that there is a relationship between ursodeoxycholate-induced bicarbonate secretion and bile flow. They are also consistent with the view that ursodeoxycholate-stimulated biliary bicarbonate secretion in the rat is strongly affected by plasma bicarbonate and PCO2, but not by plasma pH, and involves carbonic anhydrase.

To determine whether the presence of circulating desialylated glycoproteins reflect the existence and/or the severity of liver disease, 73 patients were evaluated with liver biopsies, conventional liver function tests, and the measurement of the degree of desialylation of two glycoproteins alpha 1-acid glycoprotein (alpha 1-AGP) and alpha 1-antitrypsin (alpha 1-AT). A combination of two immunological methods, available as routine laboratory tests, was used for the determination of the desialylation of alpha 1-AGP and alpha 1-AT. The severity of liver disease was assessed by a clinical classification depending upon the presence or absence of four complications (jaundice, ascites, hepatic encephalopathy, and weight loss). The presence of serum desialylated alpha 1-AGP did not allow detection of mild liver disease, but asialo alpha 1-AGP (and to a lesser extent of asialo-alpha 1-(AT) correlated with the severity of liver disease. The sensitivity of desialylated alpha 1-AGP in detection of severe liver disease was 65%, and its specificity was 80%.