Gut microbiota characterisation in obese patients before and after bariatric surgery.

Intestinal microbiota analysis of obese patients after bariatric surgery showed that Proteobacteria decreased after laparoscopic sleeve gastrectomy (SG), while it increased after laparoscopic gastric bypass (LGB). Comparing to normal weight (NW) patients, obese patients that were selected for SG showed an almost equal amount of Firmicutes and Bacteroidetes and the ratio was not affected by the surgery. Obese patients before LGB showed a predominance of Bacteroidetes, whose amount regained a relative abundance similar to NW patients after surgery. Obese patients before LGB showed the predominance of Bacteroides, which decreased after surgery in favour of Prevotella, a bacterium associated with a healthy diet. The bacteria detected at the highest percentages belonged to biofilm forming species. In conclusion, in this study, we found that the characterization of the gut microbial communities and the modality of mucosal colonisation have a central role as markers for the clinical management of obesity and promote the maintenance of good health and the weight loss.

Epidemiology of hepatitis C virus infection.

Although a lot of novel information and data on the epidemiology of hepatitis C virus (HCV) infection are available worldwide, the majority of these information are often fragmentary and sometimes contradictory. This review tries to highlight all the data available on the prevalence (i.e. the number of cases present in a known population), the risk factors, the natural history and the incidence (i.e. the number of new cases that occur every year) of HCV infection in the world, and particularly in Italy.

Human leucocyte interferon-alpha in the treatment of chronic hepatitis C.

AIM: To assess the efficacy of different schedules of human leucocyte interferon alpha in chronic hepatitis C. PATIENTS AND METHODS: A total of 213 naive patients with chronic hepatitis C were treated with 4 different schedules of human leucocyte interferon alpha. Sustained response was defined as persistently normal alanine amino transferase values with negative serum hepatitis C virus-RNA up to 12 months after therapy withdrawal. RESULTS: Rates of sustained response were 16% with 3 MU tiw for 6 months, 33% with 6 MU tiw for 5 months after a priming dose of 9 MU tiw for a month, 32% with 3 MU tiw for 12 months and 20% with 3 MU daily for 6 months. The major factors affecting the response rate were age and the hepatitis C virus genotype, as a sustained response was significantly higher in patients under 45 years and infected by hepatitis C virus types other than hepatitis C virus-1. Treatment was well tolerated and side-effects and drop-out events were similar to those described with other types of alpha-interferons. CONCLUSIONS: Human leucocyte interferon alpha appears to be equivalent to recombinant interferon-alpha in the treatment of chronic hepatitis C.

Cohort effect of HCV infection in liver cirrhosis assessed by a 25 year study.

BACKGROUND: The role of HCV infection in the development of chronic liver disease is still unclear. OBJECTIVES: Assess the presence of HCV infection in patients with liver cirrhosis. STUDY DESIGN: 123 cases of cirrhotic liver randomly selected over a 25 years period (1969-1994) from the autopsy archives of the Pathology Department of the University of Trieste, Italy, were analyzed for the presence of HCV viral genome. METHODS: Total RNA was extracted from formalin-fixed paraffin-embedded tissues of the cirrhotic liver. Genotype analysis for HCV was performed after RT-PCR by dot-blot hybridization with the three major genotype-specific probes (G1, G2 and G3). RESULTS: The overall HCV genome frequency was 50.4% (62/123). The positivity was quite constant in the 1969-1979 period (35-38%), rose to 65% in 1984, peaked to 77% in 1989 (P<0.005 vs. the previous decade), and decreased to 50% in 1994. HCV genotype G1 was found in 89% of the 62 positive samples. The mean age of death of HCV-positive and HCV-negative patients was comparable (69+/-12 vs. 67+/-16 years, NS). CONCLUSIONS: These data show an increasing frequency of HCV infection in cirrhotic liver tissues from 1969 to 1994, which peaked in 1989. The genotype G1 was the almost uniquely associated with cirrhosis. These findings indicate that the HCV infection occurred around the late 1950s-early 1960s, thus supporting the hypothesis of a cohort effect. HCV infection seems not to alter the natural history of liver cirrhosis as indicated by the comparable age at death of HCV positive and HCV negative patients.

Prevalence of and risk factors for hepatic steatosis in Northern Italy.

BACKGROUND: Although hepatic steatosis is seen with increasing frequency in clinical practice, its prevalence and risk factors are unknown. OBJECTIVE: To investigate the prevalence of and risk factors for hepatic steatosis, such as alcohol consumption and obesity. DESIGN: Cross-sectional, observational study. SETTING: Participants in the Dionysos Study. PATIENTS: 257 participants assigned to one of four categories (67 controls, 66 obese persons, 69 heavy drinkers, and 55 obese heavy drinkers). MEASUREMENTS: Ethanol intake, assessed by a validated questionnaire and expressed as daily (g/d) and lifetime (kg) consumption, and body mass, expressed as body mass index. Biochemical tests of liver and metabolic function and hepatic ultrasonography were done. RESULTS: The prevalence of steatosis was increased in heavy drinkers (46.4% [95% CI, 34% to 59%]) and obese persons (75.8% [CI, 63% to 85%]) compared with controls (16.4% [CI, 8% to 25%]). Steatosis was found in 94.5% (CI, 85% to 99%) of obese heavy drinkers. Compared with controls, the risk for steatosis was higher by 2.8-fold (CI, 1.4-fold to 7.1-fold) in heavy drinkers, 4.6-fold (CI, 2.5-fold to 11.0-fold) in obese persons, and 5.8-fold (CI, 3.2-fold to 12.3-fold) in persons who were obese and drank heavily. In heavy drinkers, obesity increased the risk for steatosis by twofold (CI, 1.5-fold to 3.0-fold) (P < 0.001), but heavy drinking was associated with only a 1.3-fold (CI, 1.02-fold to 1.6-fold) increase in risk in obese persons (P = 0.0053). Elevated alanine aminotransferase and triglyceride levels are the most reliable markers of steatosis. CONCLUSIONS: Steatosis is frequently encountered in healthy persons and is almost always present in obese persons who drink more than 60 g of alcohol per day. Steatosis is more strongly associated with obesity than with heavy drinking, suggesting a greater role of overweight than alcohol consumption in accumulation of fat in the liver.

Clinical course and risk factors of hepatitis C virus related liver disease in the general population: report from the Dionysos study.

BACKGROUND: The severity, clinical course, and risk of hepatitis C virus (HCV) related chronic liver disease are still rather poorly defined. AIMS: To investigate the prevalence, risk factors, and severity of HCV related liver disease in the general population, and investigate whether infection with a specific genotype is associated with an increased risk of cirrhosis or hepatocellular carcinoma. METHODS: HCV RNA determination by polymerase chain reaction (PCR) and HCV genotyping were performed in all anti-HCV positive subjects belonging to the Dionysos study (6917 subjects). Diagnosis of cirrhosis and hepatocellular carcinoma was established by liver biopsy in all cases. All the data were analysed by univariate and multivariate statistics in all the cohort. To investigate the natural history of HCV infection, anti-HCV positive subjects were followed up every six months for three years with liver function tests and ultrasonograms. RESULTS: The overall prevalence of HCV RNA positivity was 2.3%. Positivity increased progressively with age, and was higher in women (ratio of men to women = 0.7). Genotypes 1b and 2a were the most frequent (42 and 24% of HCV RNA positive patients), with a prevalence of 1 and 0.6% respectively. Intravenous drug use, blood transfusions received before 1990, history of previous hepatitis among the cohabiting, and history of animal (mainly dogs) bites were significantly (p<0.05) associated with HCV infection, independently of age and sex. Multivariate analysis showed that, independently of age, sex, and alcohol intake, genotype 1b infection, with or without coinfection with other genotypes, is the major risk factor associated with the presence of cirrhosis and/or hepatocellular carcinoma. During the three years of follow up, 57 (35%) of the HCV RNA positive subjects had consistently normal alanine aminotransferase and gamma-glutamyltransferase values. Two of the 22 HCV RNA positive cirrhotic patients, all drinking more than 90 g of alcohol a day, developed hepatocellular carcinoma (incidence rate = 3.0% per year). CONCLUSIONS: In the general population of Northern Italy, HCV infection is widespread, but only less than 50% of the anti-HCV positive subjects, particularly those infected with genotype 1b, are associated with a more severe liver disease. Alcohol consumption greater that 30 g a day significantly aggravates the natural course of the disease.

Treatment options in Western hepatocellular carcinoma: a prospective study of 224 patients.

BACKGROUND/AIMS: Though hepatocellular carcinoma (HCC) is one of the most frequent malignant tumors in the world, the optimal therapeutic strategy is still poorly defined. This is mainly due to geographic differences in HCC which may affect the validity of treatment regimens in differents areas of the world. The aim of the present study was to analyze the natural course of the disease as well as to assess the efficacy of different therapeutical schemes in HCC observed in Ljubljana (Slovenia) and Trieste (Italy), two cities in Western Europe situated close to each other. METHODS: During the period from January 1988 to December 1993, 224 consecutive patients (132 in Trieste and 92 in Ljubljana) with HCC were enrolled in the study. Patients were treated with the following 3 schemes: surgery 39 (17.4%), transcatheter chemoembolization (TACE) 116 (51.8%), and no treatment 69 (30.8%). The tumor was classified by Okuda staging and the liver disease by Child-Pugh score. Patients were followed up for 12-60 months, with an average of 40 months. The response rate to TACE and recurrence following surgery were evaluated. Comparative analysis of survival between different treatment groups was performed. RESULTS: The natural course of the disease, and other characteristics of the HCC, showed a typical Western type of tumor. Liver disease was scored as Child A in 58%, Child B in 30% and Child C in 12%, and the tumor was staged as Okuda I in 52%, Okuda II in 37% and Okuda III in 11%, respectively. Treatment with TACE was followed by an objective response in 27%, with a median survival of 31 months. Surgery was followed by a recurrence rate of 77% within 19.5 months and median survival of 49 months. The overall median survival of nontreated patients was 8 months. Survival in each group of patients differed significantly between all three consecutive stages of Okuda (p<0.001). In contrast, the differences in survival were significant only between Child A and B (p<0.02). The differences between Child B and C were not significant. CONCLUSIONS: This study emphasizes the importance of staging in the choice of treatment modality and diffusion of HCC in affecting an overall response to treatment and survival. Surgery is highly effective in monofocal HCC of Okuda I and II without cirrhosis. TACE is effective in Okuda I and II and Child A cirrhosis only. The treatment of HCC in Child B cirrhosis needs further studies. In Child C and/or Okuda stage III of HCC, any treatment except pure symptomatic relief is detrimental and should not be used.

Noninvasive in vivo quantitative assessment of fat content in human liver.

BACKGROUND/AIMS: Since the introduction of ultrasonography, liver steatosis has become an increasingly frequent diagnosis. Both ultrasonography (US) and computerized tomography (CT) provide qualitative rather than quantitative assessment of fatty infiltration. The objective of this study was to develop a noninvasive method for the quantification of the hepatic fat content in vivo. A test object containing solutions with CT scan density (CTD) similar to normal liver ("liver-equivalent") or "fat-equivalent material" in variable proportions was prepared to measure patients with variable degrees of steatosis in vivo. RESULTS: A linear correlation (r=0.99, p<0.001) linked CTD and the increasing percentage of fat-equivalent material. A CTD calibration curve was derived as a reference for the in vivo determinations. In 29 consecutive patients with steatosis diagnosed by histology, CTD was linearly correlated (r=0.83, p<0.001) with the hepatic fat content (HFC) expressed as percent of the whole liver, obtained by a computerized histomorphometric analysis. Based on the calibration curve obtained in 29 subjects who underwent liver biopsy, 38 additional consecutive steatotic patients were examined and the degree of hepatic fat content was calculated. The HFC was linearly correlated (r=-0.86, p<0.001) with the liver-to-spleen ratio. CONCLUSIONS: We conclude that the use of test objects allows an accurate and reproducible noninvasive quantitative assessment of hepatic fat infiltration in humans. This technique may prove useful in the evaluation of the natural course and treatment of hepatic steatosis as well as in the assessment of donor livers prior to transplantation.

Proton MR spectroscopy in quantitative in vivo determination of fat content in human liver steatosis.

To demonstrate that the lipid volume fraction in liver steatosis can be accurately estimated with in vivo hydrogen-1 magnetic resonance (MR) spectroscopy, the authors developed a calibration procedure based on in vitro MR spectroscopy of lipid extracts from steatotic liver specimens. The lipid volume fractions determined with the calibration procedure were compared with the results of histomorphometry and with calibrated computed tomographic (CT) data. The volume fraction of fat determined with MR spectroscopy was in good agreement with the CT results, whereas histomorphometry underestimated the amount of hepatic fat. The results indicate that determination of the fat volume fraction in steatotic liver can be achieved noninvasively with MR spectroscopy.

Ethanol metabolism and aging: the role of "first pass metabolism" and gastric alcohol dehydrogenase activity.

To investigate the effect of age and gender on ethanol metabolism, first-pass metabolism (FPM) and gastric alcohol-dehydrogenase (ADH) activity were compared in 32 elderly and 30 young adult nonalcoholic subjects. The FPM was obtained from the difference between the area under the curve of ethanol blood concentration after intravenous or oral administration of ethanol 0.3 g/Kg b.w. The ADH activity was determined in samples of gastric mucosa obtained during diagnostic endoscopy. In the young adult group the FPM was higher in men than in women (3.3 +/- 2.3 vs 1.2 +/- 0.9 mmol/l/h, respectively, p < .01). In aged subjects FPM was found to be very low for men (1.1 +/- 0.8 mmol/l/h, p < .001); conversely, FPM was not significantly reduced in women (1.7 +/- 0.8 mmol/l/h, p = n.s.). The gastric ADH activity was significantly (p < .01) higher in young adult men than women, whereas in aged subjects the activities were low (p < .0001) in both sexes. Thus, gender-related FPM differences equalize in the elderly or are even reversed, most likely because of gastric mucosal atrophy, which occurs more in men than women.

Interferon therapy in chronic hepatitis C virus: evidence of different outcome with respect to different viral strains.

The aim of the study was to assess the role of different viral strains of hepatitis C virus (HCV) in determining the outcome of the alpha-interferon (IFN) therapy. Fifty-seven patients (34 from Italy and 23 from Japan) with HCV-positive liver disease were enrolled in the study. The NS4 region of HCV was amplified in sera by "nested" polymerase chain reaction (PCR) using a primer pair synthesized according to the sequence of JK-1. The NS4 region was positive in 14 (41%) Italian and in 13 (56%) Japanese patients. In positive patients the sequence of the NS4 region was also obtained. Subsequently, HCV genotype was determined in all patients by PCR amplification of the core region. All patients received recombinant alpha 2a-interferon (IFN), 6 million units 3 times a week for 1 month followed by 3 million units 3 times a week for 5 months. The patients were followed for 1 year after the end of treatment. At the end of the follow-up, 17 (30%) had sustained normal levels of serum alanine aminotransferase (ALT). The outcome of treatment was not correlated with race, age, sex, histology, and pretreatment ALT level, but was significantly (P < 0.00001) associated with the presence of both the NS4-JK-1 region and HCV type II. Among the 27 NS4-positive patients, only 1 patient (3.7%) achieved a complete response, whereas the remaining 26 patients (95.3%) either were non-responders or relapsed after IFN was discontinued.(ABSTRACT TRUNCATED AT 250 WORDS)

Different genotypes of hepatitis C virus are associated with different severity of chronic liver disease.

The presence of the "Japanese type" NS4 region was investigated in two series of patients (53 from Italy and 58 from Japan) with hepatitis C virus (HCV)-related chronic liver disease. The two populations were homogeneous as regard to age, male/female ratio, histological diagnosis, and serum aminotransferase activities. Genomic amplification was carried out by "nested" polymerase chain reaction (PCR) with a pair of primers synthesized according to the sequence of JK-1 isolated in Japan. The presence of viral replication was confirmed further by PCR amplification of the 5'NC region. The NS4 region of the Japanese strain was detected in 24 sera (45%) from Italy and in 44 (71%) from Japan. NS4-positive patients were significantly older and showed an ALT serum level significantly lower (P < 0.01) than NS4 negative cases in each group. Cirrhosis was significantly (P < 0.0007) more common in NS4-positive than in NS4-negative patients. The HCV genotype was subsequently obtained according to Okamoto. All the NS4-positive patients were infected by Type II, whereas in NS4-negative patients all four genotypes were present though Type II still constituted the majority. Cirrhosis was associated exclusively with Type II both in NS4-positive and -negative subjects. These data indicate that, although the positivity for NS4 "Japanese" region seems to be associated with a more aggressive liver disease, the most prevalent Type II predicts more specifically those who are likely to develop cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)

1H NMR spectroscopic studies of lipid extracts from human fatty liver.

Lipid extracts of biopsy samples from normal and non-alcohol-induced fatty human liver were studied by 1H-NMR at 200 MHz. Spectra of the lipid extracts from 10 mg samples were obtained in 6 min with routine acquisition parameters and allowed the calculation of the phosphatidylcholine to total fatty acyl chain ratio, the cholesterol to total fatty acyl chain ratio, the average fatty acyl chain length, the unsaturation ratio and the acylated glycerol to total fatty acyl chain ratio. The data suggest that lipids with a higher ratio of de novo synthesized fatty acyl chains are stored in non-alcohol-induced fatty liver. NMR lipid analysis appears to be a reliable method for the rapid assessment of hepatic lipid composition on bioptic specimens.

Fatty infiltration of the liver. Quantification by 1H localized magnetic resonance spectroscopy and comparison with computed tomography.

RATIONALE AND OBJECTIVES: The authors evaluated the degree of fatty infiltration of the liver in subjects with diffuse liver steatosis using image-guided 1H localized MR spectroscopy and correlated the magnetic resonance (MR)-determined fat fraction with the computed tomography (CT) liver/spleen density ratio and histologic evaluation. METHODS: MR measurements were performed at 1.5 T by applying a double-spin-echo localization sequence. Twenty-six patients underwent MR and CT examinations and ultrasound (US)-guided biopsy. Additionally, three healthy volunteers underwent MR examination. Steatosis severity was estimated using 1) the ratio between fat and total MR signal areas; 2) the ratio between liver and spleen CT number; and 3) histologic score. RESULTS: The linear correlation between MR fat/fat-plus-water signal ratio and CT liver/spleen density values ratio is statistically significant. Both techniques correlate well with histologic score. No significant correlation exists between water or fat T2 values and the severity of steatosis. CONCLUSIONS: 1H MR spectroscopy allows a noninvasive estimate of the hepatic fat content.

Incidence of hepatocellular carcinoma in Italy: what could we learn from autoptic studies?

From January 1, 1968 to December 31, 1984, 31,955 autopsies were performed at the Department of Pathology of the University of Trieste. Of these 16,521 were male and 15,434 female which covered about 70% of the population who died in the area over the recent years. Hepatocellular carcinoma (HCC) associated with liver cirrhosis was encountered in 441 cases (380 males and 61 females, M:F ratio 5.8:1) with an overall occurrence of 1.4% in the autoptic population. On the contrary and in the absence of chronic liver disease HCC was only observed in 0.3% of the cases (45 males and 16 females, M:F ratio 2.7:1). Liver cirrhosis accounted for 10% of autopsies (2099 males and 1104 females, M:F ratio 1.8:1). A 15% of cirrhosis was associated with HCC, indicating that major attention should be paid to cirrhotic patients, in particular males after the 5th decade of life. The year distribution of HCC and cirrhosis was fairly constant during the period of time considered. These data suggest that: i) HCC is common in Italy; ii) in the vast majority, HCC occurs in the presence of cirrhosis; and iii) HCC appears to be a rather late disease as it does not reduce the life expectancy of cirrhotic and control populations. Since reliable, nationwide epidemiological data are not available in Italy, it is not known whether these data represent a local realty or whether they may be extrapolated to the entire country. Cooperative and prospective studies appear appropriate in investigating possible geographical differences in HCC distribution and permit a better understanding and prevention of the disease.

Detection of hepatitis B virus transcripts in patients with chronic liver disease.

Hepatitis B virus (HBV) transcription was studied by Northern blot analysis on total cellular RNA purified from liver biopsies in 70 patients with chronic liver disease (24 HBsAg positive, 15 antiHBs and/or antiHBc positive, 31 HBV negative). No transcripts were found in the HBV negative and in the antiHBs and/or antiHBc positive patients. In the others, three major RNA species were identified: i. a 3.5 kb transcript corresponding to the RNA pregenome; ii. 2.4-2.1 kb transcript corresponding to the s and preS1 gene RNA; iii. lower molecular weight species. All three forms were present simultaneously only in patients with active viral replication, with a strict relation between the presence of the 3.5 kb RNA in the liver and serum HBV-DNA. In conclusion, Northern blot analysis can easily be performed to study viral replication and it can contribute to a better understanding of the molecular processes underlying HBV infection and leading to liver disease in man.