Chronic hepatitis C. Advances in diagnostic testing and therapy.

The methods for diagnosing hepatitis C virus infection have been evolving since the first-generation enzyme-linked immunosorbent assay antibody test was devised in 1989. In addition to assaying for serum antibodies against viral proteins, serum and liver tissue can be tested for viral RNA, evidence of ongoing viral replication. The improving ability to diagnose hepatitis C has furthered the understanding of the natural history of this infection. Acute hepatitis C results in chronic elevations of serum transaminase levels following nearly one half of cases. Cirrhosis complicates approximately 20% of chronic infections. Long-standing chronic hepatitis C may play a role in the pathogenesis of hepatocellular carcinoma. Sustained normalization of serum transaminase levels, often accompanied by a decrease in or disappearance of viral RNA, occurs in approximately 25% of patients with chronic hepatitis C who are treated with a 6-month course of recombinant interferon alfa. This treatment can occasionally be complicated by hematologic, endocrinologic, and psychiatric adverse effects but is usually fairly well tolerated. Whether interferon therapy will diminish the risk of cirrhosis or carcinoma is not yet known. This article reviews the diagnosis of chronic hepatitis C infection as well as the mechanisms of action, efficacy, and adverse effects associated with interferon alfa therapy.

Revised estimates of diagnostic test sensitivity and specificity in suspected biliary tract disease.

BACKGROUND: The purpose of this study was to estimate the sensitivity and specificity of diagnostic tests for gallstones and acute cholecystitis. METHODS: All English-language articles published from 1966 through 1992 about tests used in the diagnosis of biliary tract disease were identified through MEDLINE. From 1614 titles, 666 abstracts were examined and 322 articles were read to identify 61 articles with information about sensitivity and specificity. Application of exclusion criteria based on clinical and methodologic criteria left 30 articles for analysis. Cluster-sampling methods were adapted to obtain combined estimates of sensitivities and specificities. Adjustments were made to estimates that were biased because the gold standard was applied preferentially to patients with positive test results. RESULTS: Ultrasound has the best unadjusted sensitivity (0.97; 95% confidence interval, 0.95 to 0.99) and specificity (0.95; 95% confidence interval, 0.88 to 1.00) for evaluating patients with suspected gallstones. Adjusted values are 0.84 (0.76 to 0.92) and 0.99 (0.97 to 1.00), respectively. Adjusted and unadjusted results for oral cholecystogram were lower. Radionuclide scanning has the best sensitivity (0.97; 95% confidence interval, 0.96 to 0.98) and specificity (0.90; 95% confidence interval, 0.86 to 0.95) for evaluating patients with suspected acute cholecystitis; test performance is unaffected by delayed imaging. Unadjusted sensitivity and specificity of ultrasound in evaluating patients with suspected acute cholecystitis are 0.94 (0.92 to 0.96) and 0.78 (0.61 to 0.96); adjusted values are 0.88 (0.74 to 1.00) and 0.80 (0.62 to 0.98). CONCLUSIONS: Ultrasound is superior to oral cholecystogram for diagnosing cholelithiasis, and radionuclide scanning is the test of choice for acute cholecystitis. However, sensitivities and specificities are somewhat lower than commonly reported. We recommend estimates that are midway between the adjusted and unadjusted values.

Vitamin A hepatotoxicity: a cautionary note regarding 25,000 IU supplements.

Vitamin A hepatotoxicity has been reported at doses exceeding 50,000 IU/day. At 25,000 IU vitamin A per day, although elevated liver enzymes may be seen, hepatotoxicity is rare. We report a case of severe hepatotoxicity associated with the habitual daily ingestion of 25,000 IU of vitamin A bought as an over-the-counter dietary supplement. With the general availability of high-dose supplements and recent literature emphasizing the importance of vitamin A adequacy, the potential for vitamin A hepatotoxicity may increase. Health professionals should remain aware of the potential for vitamin A hepatotoxicity and elicit a vitamin A history in all patients being evaluated for liver dysfunction.

Nonalcoholic steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is a liver disease that, until recently, has been underrecognized as a common cause of elevated liver enzymes. This distinct clinical entity is characterized by liver biopsy findings similar to those seen in alcoholic hepatitis but in the absence of alcohol consumption sufficient to cause such changes. Patients with NASH are often middle-aged and obese, with coexisting diabetes or hyperlipidemia, but NASH also occurs in younger lean, otherwise healthy individuals and even in children. Although NASH is generally a benign disorder, it may be progressive, leading to cirrhosis and complications of portal hypertension. Liver biopsy remains the gold standard for diagnosis. Therapy for NASH remains poorly defined, although weight reduction and ursodeoxycholic acid may have a beneficial effect.

Correlation of percutaneous liver biopsy fragmentation with the degree of fibrosis.

BACKGROUND: Although fragmentation of a liver biopsy specimen has been considered to be suggestive of cirrhosis, the evidence for this is difficult to find in the published literature. AIM: To determine whether fragmentation of percutaneous liver biopsy specimens correlates with the degree of fibrosis. METHODS: One hundred and eighty-six patients underwent percutaneous liver biopsy prospectively. The specimens were measured for the length and number of fragments. The extent of fibrosis was scored by a pathologist blind to the clinical data. Length and fragmentation data were compared between the different stages. RESULTS: The overall median fragment length was 1.85 cm and the median fragment number was four. Specimens with advanced fibrosis (stages III-IV) had more fragments than those with no or mild fibrosis (stages 0-II) (P < 0.0001). The aggregate fragment length decreased with increasing stage of fibrosis (P < 0.0001). Specimens with greater than 12 fragments were seen only with advanced fibrosis. CONCLUSIONS: Fragmentation of percutaneous liver biopsy specimens is common and increases with progression from early to advanced fibrosis. Fibrotic specimens fragment more often and more extensively.

A randomized trial of high-dose interferon alpha-2b, with or without ribavirin, in chronic hepatitis C patients who have not responded to standard dose interferon.

BACKGROUND: Conventional interferon monotherapy fails to achieve virological clearance in most hepatitis C-infected patients. The use of high-dose induction regimens may improve the initial clearance of virus, while the addition of ribavirin appears to improve the rates of sustained response once clearance is achieved. AIM: To compare the efficacy and safety of re-treatment with an induction regimen of high-dose interferon alpha-2b, with or without ribavirin, in chronic hepatitis C patients who have not responded to standard dose interferon monotherapy. METHODS: Previous virological non-responders to standard dose interferon (3-5 MU three times weekly for > or = 12 weeks) were randomized to receive, unblind, either 10 MU interferon alpha-2b daily for 10 days, then 5 MU daily for 74 days, then 5 MU three times weekly for 24 weeks (total 36 weeks) (group A), or the above regimen with the addition of ribavirin, 1000-1200 mg/day, at day 11 (group B). All patients were followed up for 24 weeks after completion of therapy. RESULTS: End of treatment virological response was noted in one of 10 (10%) patients in group A and in eight of 15 (54%) patients in group B (P=0.04). The sole end treatment responder in group A and three in group B relapsed on follow-up. The apparent improvement in response in group B compared to group A nearly reached statistical significance (group B 5/15 vs. group A 0/10; P=0.06). CONCLUSIONS: In this small pilot study, a 36-week high-dose induction interferon monotherapy protocol did not yield sustained responses in previous non-responders to standard dose interferon. However, the same regimen with ribavirin yielded a 33% sustained response rate, nearly reaching statistical significance. The therapy was well tolerated, despite the higher doses of interferon used and the addition of ribavirin. High-dose interferon with ribavirin appears to be a therapeutic option for non-responders to conventional interferon monotherapy.

Black pigment gallstones with cholesterol gallstones in the same gallbladder. 13 cases in a surgical series of 1226 patients with gallbladder stones.

We studied 1312 consecutive patients who underwent surgery for gallstones in the biliary tract at one university hospital in Siena, Italy, with a systematic classification of gallstones found within the gallbladder. Of these patients, 1226 were found to have gallbladder stones; 94 of these had black pigment gallstones. Of these, 13 patients were found to have black pigment gallstones and cholesterol gallstones within their gallbladder. They all had multiple black pigment gallstones, usually very small (all < 6 mm diameter), in association with larger cholesterol stones in the gallbladder lumen. The cholesterol gallstones were single in seven cases, double in two cases, and multiple in four cases. All 13 of these patients with black pigment stones in association with cholesterol stones had histologic evidence of either adenomyomatosis or Rokitansky-Aschoff sinuses in the gallbladder wall. In nine of the 13 patients, the black pigment stones were located both in the gallbladder lumen and in close association with the gallbladder wall (in areas of adenomyomatosis or in Rokitanski-Aschoff sinuses). In the other four patients, the stones were found in close association with the gallbladder wall alone and not freely mobile within the gallbladder lumen. It is concluded that cholesterol stones and black pigment stones may be found in the same gallbladder. This association is infrequent with an incidence of 13 of 1226 (1.06%) in our series. There appears to be some relationship between the formation of the black pigment stones and the presence of adenomyomatosis or Rokitanski-Aschoff sinuses.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of extracorporeal shock wave lithotripsy and ursodeoxycholic acid on gallbladder motility.

Extracorporeal shock wave lithotripsy and dissolution agents are useful nonsurgical therapies for gallstones. Their effect on gallbladder emptying is unclear. We evaluated emptying by ultrasonography before and after lithotripsy in 50 patients on ursodeoxycholic acid or placebo and in nine controls. At baseline, patients had normal (68.8 +/- 3.2%) or delayed emptying (14.5 +/- 3.3%). In a subset of 24 patients, lithotripsy increased fasting volume (26.6 +/- 3.0 to 43.8 +/- 5.0 ml, P < 0.005), postprandial volume (11.3 +/- 3.1 ml to 22.9 +/- 3.0 ml, P < 0.05), and decreased ejection fraction (70.0 +/- 4.1% to 42.7 +/- 6.0%, P < 0.0005). There was an inverse linear correlation between power and ejection fraction, r = -0.43, P < 0.005. Ursodeoxycholic acid increased fasting (23.3 +/- 2.2 ml to 36.7 +/- 4.6 ml, P < 0.005) and postprandial volume (11.1 +/- 1.8 to 17.6 +/- 2.5, P < 0.005). Treatment with ursodeoxycholic acid resulted in a greater decrease in fragment size compared to placebo after lithotripsy in patients with fragment size greater than 6 mm. In conclusion, both lithotripsy and ursodeoxycholic acid have an effect on gallbladder emptying.

Gallbladder mucin and cholesterol and pigment gallstone formation in hamsters.

We measured gallbladder mucin production by hamsters fed diets lithogenic for either cholesterol or pigment gallstones. In hamsters on the cholesterol stone diet, gallbladder production of 3H-glucosamine-labeled mucin was elevated two- and seven-fold after 1 and 3 weeks, respectively. After 1 week cholesterol crystals were seen in a mucus gel on the gallbladder surface. In hamsters on the pigment stone diet, gallbladder mucin production was significantly elevated after 1 and 3 weeks. The first precipitation of pigment crystals was in mucus in bile or on the gallbladder surface. Black pigment stones grew by agglomeration of pigment crystals enmeshed in mucus. In conclusion, gallbladder mucin production is increased before cholesterol or pigment stone formation, and the earliest deposition of crystals is in mucus in bile or on the gallbladder surface.

Ursodiol for hepatobiliary disorders.

PURPOSE: To explain the rationale supporting the use of ursodiol (ursodeoxycholic acid) for the treatment of patients with cholesterol gallstones and chronic liver diseases and to describe the results obtained in clinical trials. DATA SOURCES: Personal databases of the authors and MEDLINE were used to identify relevant English-language articles. STUDY SELECTION: Randomized controlled trials evaluating ursodiol for the treatment of patients with cholesterol gallstones and chronic liver diseases were emphasized. DATA SYNTHESIS: Ursodiol is at least as effective as chenodiol (chenodeoxycholic acid) for the dissolution of cholesterol gallstones and is associated with fewer adverse effects. Ursodiol desaturates bile, solubilizing cholesterol from the stone surface. The diameter of the largest stone is the most important determinant of successful dissolution. Dissolution with ursodiol is effective for approximately 30% to 50% of stones smaller than 20 mm in diameter, with the best results for small, buoyant stones. A meta-analysis of randomized trials with ursodiol found that the dissolution rate was 37% for patients treated with ursodiol at doses of more than 7 mg/kg per day or of more than 500 mg/d for at least 6 months. Maintenance therapy is effective for prevention of gallstone recurrence. Ursodiol also improves biochemical markers of cholestasis and inflammation when used to treat cholestatic liver diseases. By displacing potentially hepatotoxic bile salts, it appears to interrupt the cycle of cholestatic injury. It may also exert hepatoprotective membrane-stabilizing or immunomodulatory effects (or both). Improvements in laboratory variables are limited to the treatment period, with relapses after withdrawal of therapy. Pruritus may be markedly relieved in individual patients treated with ursodiol. CONCLUSIONS: Ursodiol is a safe and effective therapy for the treatment of patients with cholesterol gallstones. Although treatment with ursodiol leads to improvement in biochemical markers for cholestatic liver diseases, whether it alters the natural history of these disorders is the subject of ongoing trials.

The calcium ionophore A23187 stimulates glycoprotein secretion by the guinea pig gallbladder.

The purpose of this study was to examine the role of calcium ions in gallbladder glycoprotein secretion in cultured guinea pig gallbladder explants. The calcium ionophore A23187 showed a threshold of 2 micrograms per ml medium for stimulation of secretion of [3H]glucosamine-labeled glycoproteins over a 30 min incubation period. The ionophore at 3 and 5 micrograms per ml medium resulted in a 3- to 4-fold increase in secretion of [3H]glucosamine-labeled glycoproteins. Ionophore-induced stimulation of glycoprotein secretion was abolished by the addition of 0.01 mM verapamil to the medium. To study the effect of changes in extracellular calcium on basal glycoprotein secretion, explants were cultured for 24 hr in media with 0.007, 0.5 or 2.0 mM calcium; no differences in basal glycoprotein secretion were observed. When cultured in medium with 1.0 mM EGTA, basal secretion decreased significantly vs. controls in 0.007 mM total calcium medium. Total [3H]glucosamine incorporation by explants in medium with EGTA was unaltered, however, suggesting that the low level of calcium in the medium was selectively impairing the secretory process. These findings indicate that calcium ions are important in the regulation of gallbladder glycoprotein secretion.

Composition of pigmented centers of cholesterol gallstones.

Most cholesterol gallstones have visually pigmented centers, but it is unclear whether this represents simple co-precipitation of pigment with cholesterol during stone nidation or nidation on a true pigment stone center. To clarify this issue, we selected from among 67 sets of cholesterol gallstones, 12 sets with the most conspicuously pigmented centers. The composition of the centers and the peripheries of these 12 stones was analyzed using infrared spectroscopy and compared with that of 10 black pigment gallstones. The pigmented centers of cholesterol stones contained 80.1 +/- 7.9% (mean +/- S.E.) cholesterol, 6.2 +/- 3.4% calcium bilirubinate (only 4 of the 12 centers had measurable calcium bilirubinate), trace amounts of calcium phosphate and no calcium carbonate or calcium palmitate. The peripheral areas of the cholesterol stones contained 91.6 +/- 2.3% cholesterol and no detectable calcium salts. For comparison, the composition of the centers of 10 black pigment gallstones was 13.5 +/- 2.2% cholesterol, 28.2 +/- 5.3% calcium bilirubinate, 5.5 +/- 2.4% calcium phosphate and 10.6 +/- 5.8% calcium carbonate. The composition of only one cholesterol stone center (15.8% cholesterol, 26.8% calcium bilirubinate) resembled that of a pigment stone, but even this center differed from that of a typical pigment stone in that it contained only a trace amount of calcium phosphate and no calcium carbonate. Thus, the chemical composition of pigmented centers of cholesterol gallstones is quantitatively different from that of black pigment stones, suggesting that cholesterol gallstones do not form on a pigment stone nidus.

Chemical and morphologic characteristics of cholesterol gallstones that failed to dissolve on chenodiol. The National Cooperative Gallstone Study.

During the National Cooperative Gallstone Study, chenodiol (chenodeoxycholate), 750 or 375 mg/day, resulted in complete gallstone dissolution in only 13.5% and 5.2% of patients, respectively. The purpose of this study was to analyze the composition and morphology of gallstones from patients who underwent cholecystectomy during the National Cooperative Gallstone Study to determine if calcium salts on the gallstone surface could have been responsible for failure of dissolution. Total gallstone calcium content was not different between the treated and placebo groups; however, surface calcium levels were different, being greater than 1.0% in 47.6% of stones from chenodiol-treated patients (n = 63) but in only 16.7% of those from placebo-treated patients (n = 18), p less than 0.02. Pigmented outer rims were found in 52.4% of the stones from the chenodiol-treated group compared with only 16.7% of stones from the placebo group, p less than 0.01. The rim calcium content of 36 stones with pigmented outer rims was 3.7% +/- 1.0%, whereas that of 45 stones with nonpigmented outer rims was only 1.0% +/- 0.3%, p less than 0.01. We conclude that the presence of rings of increased concentrations of calcium salts on the gallstone surface may impair dissolution by chenodiol.

Stratification of gallstone fragments: the key to more effective fragmentation.

During previous experiments with in vitro fragmentation in a simulated gallbladder, we noticed that stone fragments tended to stratify with the dust and smaller fragments settled to the dependent portion, while the larger fragments settled on top. We reviewed the oral cholecystogram (OCG) of 10 patients examined 6 months following gallstone lithotripsy. In all cases with adequate visualization of stone fragments, the stratification phenomenon was observed. We hypothesized that adjusting the shock wave focus to target on these large fragments would improve the efficiency of fragmentation. To test this hypothesis, we fragmented three matched pairs of gallstones in vitro. For each pair, the stones were removed from the same gallbladder and the stone weights of the two stones were within 10%. The smaller member of each pair was fragmented using the "old method" with the focus on the fragment line. The larger stone was fragmented with the "new method" with the focus in the acoustic shadow deep to the echogenic line caused by the dust and small fragments in the dependent portion. The distribution of fragments was analyzed by passing the fragments through a series of filters. With the new method of targeting, the proportion of fragments less than 1.5 mm was doubled while the fragments greater than 5 mm were eliminated. The new method of targeting, taking into account the stratification of stone fragments, produces more effective fragmentation and should lead to more rapid clearance of fragments from the gallbladder.

Bile and stone analysis in two infants with brown pigment gallstones and infected bile.

Two infants under 3 mo of age who presented with obstructive jaundice secondary to cholelithiasis are reported. Neither infant had any congenital anatomic abnormality of the biliary tract leading to stasis, yet both had cultures of gallbladder bile that grew abundant bacteria. In both, recovery of gallbladder bile and sludge or actual stones allowed a detailed analysis of bile and stone composition. Bile was not saturated with cholesterol. In both cases, unconjugated bilirubin accounted for a large percentage of the total bile biliary pigments measured, and stercobilin was present in gallbladder bile. Bile beta-glucuronidase activity was higher when measured at the optimal pH of bacterial rather than tissue beta-glucuronidase. Analysis of stone morphology and composition showed characteristics of brown pigment gallstones with a layered appearance and the presence of calcium palmitate. This is the first report of detailed bile and stone analysis in infants and supports the hypothesis that brown pigment gallstones form spontaneously in infants who have bacterial infections in the biliary tract.

Effect of phenobarbital on serum and biliary parameters in a patient with Crigler-Najjar syndrome, type II and acquired cholestasis.

The effect of phenobarbital treatment on bilirubin metabolism and bile secretion was studied in a patient with Crigler-Najjar syndrome, type II and acquired cholestasis. Following cholecystectomy and choledochostomy, a balloon inflatable T tube was inserted to facilitate bile collection. Hepatic UDP-glucuronyltransferase in surgically obtained liver tissue was 25% of normal activity and bilirubin monoconjugates accounted for greater than 80% of the pigments in bile. Phenobarbital therapy decreased the concentration of fasting serum bile acids by 33% and partially reestablished their enterohepatic cycling postprandially. The total fasting serum bilirubin concentration (greater than 90% unconjugated) increased 21% during phenobarbital treatment and was unaffected by caloric intake. Bile flow was increased 2.7 times after phenobarbital treatment. The biliary concentration of total bilirubin was increased 2.4 times, primarily due to monoconjugated bilirubin, which accounted for 91% of the biliary pigments. Bile acid, phospholipid, cholesterol, and calcium concentrations in bile were significantly increased after phenobarbital. The data indicate that even in the presence of cholestasis an underlying deficiency in bilirubin conjugation may be confirmed by biliary pigment analysis.

Black and brown pigment gallstones differ in microstructure and microcomposition.

The two subtypes of pigment gallstones, black and brown stones, differ in chemical composition and pathogenesis. We examined a black bilirubinate stone and a black phosphate stone (which represented opposite ends of the compositional spectrum of black noncarbonate stones), a black carbonate stone, and a brown pigment stone using scanning electron microscopy and microchemical techniques to determine if stone microstructure and microcomposition reflected different patterns of formation. The cross-sectional surfaces of the black bilirubinate and black phosphate stones were smooth and homogenous. Electron probe microanalysis demonstrated high concentrations of sulfur and copper in the center of the black bilirubinate stone; sulfur was in a low valence state consistent with disulfide linkages in proteins. The brown stone was rough-surfaced with lamellated bands on cross-section. The lighter-colored bands in this stone contained virtually all of the detected calcium palmitate, while the darker sections contained much more calcium bilirubinate. Plasma oxygen etching demonstrated a network of protein interdigitating with calcium bilirubinate salts in the black bilirubinate and black phosphate stones but not in the black carbonate or brown stones. Argon ion etching demonstrated that calcium bilirubinate was in a closely packed rod-shaped arrangement in all three black stones but not in the brown stone. We conclude that the marked differences in structure and composition between the black noncarbonate and brown pigment gallstones support the hypothesis that the two major pigment gallstone types form by different mechanisms. In addition, the layered structures of the black carbonate and brown stones suggest that stone growth is affected by cyclic changes in biliary composition.

Gallstone composition in relation to buoyancy at oral cholecystography.

Although it is recognized that some gallstones float at oral cholecystography, the reasons for this are not known. To determine how stone type and composition are related to stone buoyancy, the authors analyzed gallstones from 90 patients in the National Cooperative Gallstone Study. Seventeen patients had floating and 73 had nonfloating radiolucent stones at oral cholecystography. Stone analysis showed that all 17 floating stones were cholesterol stones; 64 of the nonfloating stones were cholesterol stones, while nine were pigment stones. The cholesterol contents of floating and nonfloating cholesterol stones were similar, 90.4% +/- 1.7 and 87.0% +/- 1.2 of stone weight, respectively. The calcium salt content of the nonfloating cholesterol stones was 3.2% +/- 0.6, while that of the floating cholesterol stones was only 1.1% +/- 0.4 (P = .02). The results indicate that floating gallstones are cholesterol stones with a significantly lower calcium salt content than that of nonfloating cholesterol stones.

Nonvisualized gallbladder on oral cholecystography: implications for lithotripsy.

Currently, most protocols evaluating the efficacy of gallstone lithotripsy require a visualized gallbladder on oral cholecystography (OCG). The primary purpose of the OCG is to establish that the cystic duct is patent. When the gallbladder is visualized on OCG, it can also be used to number and size gallstones accurately. Patients with non-visualization of the gallbladder on OCG are excluded from consideration for lithotripsy. The purpose of this study was to evaluate retrospectively the ultrasonographic findings (i.e., number and sizes of stones in 32 patients with nonvisualization on the OCG). In 11 patients (34%) ultrasound (US) did not detect any stone, and it is presumed that the gallbladder failed to visualize for other reasons. Six patients (19%) had one or two stones and 15 (47%) patients had more than three stones. This suggests that 20% of patients with nonvisualization of the gallbladder on OCG would otherwise be eligible for lithotripsy provided that patency of the cystic duct can be demonstrated by other means, such as computed tomographic (CT) examination with oral biliary contrast or cholescintigraphy.