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Dive into the research topics where Emmanuel Tsochatzis is active.

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Featured researches published by Emmanuel Tsochatzis.


The American Journal of Gastroenterology | 2006

The evolving role of leptin and adiponectin in chronic liver diseases.

Emmanuel Tsochatzis; George V. Papatheodoridis; Athanasios J. Archimandritis

Leptin and adiponectin, the main metabolic products of adipose tissue, have been implicated in a wide spectrum of human diseases. Given the frequent presence of hepatic steatosis in several chronic liver diseases, there is currently increasing interest in the role of these adipokines in the development of hepatic steatosis and also in necroinflammation and fibrosis, mostly in patients with nonalcoholic fatty liver disease or chronic hepatitis C. According to experimental data, reduced adiponectin levels and increased leptin levels associated with leptin resistance, which are usually observed in obese patients with or without metabolic syndrome, may result in fat accumulation in the liver and in the enhancement of liver inflammation and mostly fibrogenesis. Increased leptin and decreased adiponectin serum levels have been detected initially in patients with nonalcoholic steatohepatitis and more recently in patients with chronic hepatitis C compared to healthy controls in most but not all studies, while the data on the associations between these adipokine levels and the severity of hepatic steatosis or fibrosis are still rather conflicting. However, several potential confounding parameters were not evaluated in all studies. Therefore, the associations between adipokines and liver histological lesions and their effects on liver cells should be evaluated further in prospective, carefully designed studies, including larger cohorts of patients with detailed assessment of metabolic and other potential confounding factors.


PLOS ONE | 2009

A novel immunological assay for hepcidin quantification in human serum.

Vasiliki Koliaraki; Martha Marinou; Theodoros P. Vassilakopoulos; Eustathios Vavourakis; Emmanuel Tsochatzis; Gerassimos A. Pangalis; George V. Papatheodoridis; Alexandra Stamoulakatou; Dorine W. Swinkels; George Papanikolaou; Avgi Mamalaki

Background Hepcidin is a 25-aminoacid cysteine-rich iron regulating peptide. Increased hepcidin concentrations lead to iron sequestration in macrophages, contributing to the pathogenesis of anaemia of chronic disease whereas decreased hepcidin is observed in iron deficiency and primary iron overload diseases such as hereditary hemochromatosis. Hepcidin quantification in human blood or urine may provide further insights for the pathogenesis of disorders of iron homeostasis and might prove a valuable tool for clinicians for the differential diagnosis of anaemia. This study describes a specific and non-operator demanding immunoassay for hepcidin quantification in human sera. Methods and Findings An ELISA assay was developed for measuring hepcidin serum concentration using a recombinant hepcidin25-His peptide and a polyclonal antibody against this peptide, which was able to identify native hepcidin. The ELISA assay had a detection range of 10–1500 µg/L and a detection limit of 5.4 µg/L. The intra- and interassay coefficients of variance ranged from 8–15% and 5–16%, respectively. Mean linearity and recovery were 101% and 107%, respectively. Mean hepcidin levels were significantly lower in 7 patients with juvenile hemochromatosis (12.8 µg/L) and 10 patients with iron deficiency anemia (15.7 µg/L) and higher in 7 patients with Hodgkin lymphoma (116.7 µg/L) compared to 32 age-matched healthy controls (42.7 µg/L). Conclusions We describe a new simple ELISA assay for measuring hepcidin in human serum with sufficient accuracy and reproducibility.


Scandinavian Journal of Gastroenterology | 2008

Serum adipokine levels in chronic liver diseases: Association of resistin levels with fibrosis severity

Emmanuel Tsochatzis; George V. Papatheodoridis; Emilia Hadziyannis; Anastasia Georgiou; Georgia Kafiri; Dina Tiniakos; Emanuel K. Manesis; Athanasios J. Archimandritis

Objective. Leptin and adiponectin have been implicated in the pathogenesis and progression of non-alcoholic steatohepatitis (NASH) and chronic hepatitis C (CHC), but little is known about the role of resistin in chronic liver diseases. The objective of this study was to investigate serum levels of the above three adipokines in relation to the etiology of liver disease and to determine their associations with histological severity. Material and methods. We prospectively evaluated 146 patients (HBeAg-negative chronic hepatitis B (CHB): 52, CHC: 70, NASH: 24) who consecutively underwent liver biopsy. Detailed epidemiological, anthropometric and laboratory data were recorded. Histological lesions were evaluated blindly according to the Ishak and the Brunt classifications for CHB/CHC and NASH, respectively. Results. Serum adipokine levels were similar between CHB and CHC patients, while CHB/CHC patients had significantly lower leptin levels compared with NASH patients (8.3±7.3 versus 17.6±16.6 ng/ml, p=0.012) and higher adiponectin (10.2±5.1 versus 7.5±4 µg/ml, p=0.018) and resistin levels (7.1±2.5 versus 5.7±2.8 ng/ml, p=0.016). In CHB/CHC, there was no significant association between steatosis or necroinflammation and levels of adipokines, while the presence of moderate/severe fibrosis (stages 4–6) was associated with higher leptin and adiponectin levels in male but not in female patients and with lower resistin levels irrespective of gender or other factors (adjusted odds ratio=0.788, p=0.035). Conclusions. Serum adipokine levels depend on the etiology of liver disease differing between chronic viral hepatitis and NASH, but not between CHB and CHC. In CHB/CHC, resistin levels are independently associated with fibrosis severity, whereas in the association of leptin and adiponectin levels with fibrosis, it seems to be a gender effect.


Scandinavian Journal of Gastroenterology | 2009

Insulin resistance and metabolic syndrome in chronic liver diseases: Old entities with new implications

Emmanuel Tsochatzis; Spilios Manolakopoulos; George V. Papatheodoridis; Athanasios J. Archimandritis

Insulin resistance (IR) and metabolic syndrome have recently been implicated in the pathogenesis and progression of chronic liver diseases, especially chronic hepatitis C (CHC) and non-alcoholic fatty liver disease (NAFLD). In this review, we provide current information on their deleterious effect on the liver, with particular interest in those two entities. In NAFLD, IR causes both the accumulation of fat in hepatocytes and the progression to non-alcoholic steatohepatitis (NASH). Moreover, the presence of metabolic syndrome seems to be associated with severe fibrosis in NASH patients. In CHC, IR develops early in the course of the disease and precedes steatosis. It is also independently associated with histological severity and negatively affects treatment response, irrespective of genotype. Consequently, therapies targeting IR and metabolic syndrome could indirectly ameliorate the prognosis of both NAFLD and CHC. As specific therapies do not exist, patients with metabolic syndrome and CHC and NAFLD should be counseled to lose weight and ameliorate their glycemic control and lipid profile.


Alimentary Pharmacology & Therapeutics | 2007

Metabolic syndrome is associated with severe fibrosis in chronic viral hepatitis and non‐alcoholic steatohepatitis

Emmanuel Tsochatzis; George V. Papatheodoridis; E. K. Manesis; G. Kafiri; Athanasios J. Archimandritis

BACKGROUND The prevalence of metabolic syndrome and its possible impact on the severity of liver histological lesions have not been studied prospectively in chronic liver diseases. AIM To investigate the prevalence of metabolic syndrome in patients with chronic viral hepatitis or non-alcoholic steatohepatitis, and to determine its associations with histological severity. METHODS We prospectively included 317 patients (hepatitis B e antigen-negative chronic hepatitis B: 95, chronic hepatitis C: 176, non-alcoholic steatohepatitis: 46) with liver biopsy. Metabolic syndrome was defined using the Adult Treatment Panel III criteria. Histological lesions were evaluated according to Ishaks or Brunts classification. RESULTS Metabolic syndrome was present in 10.4% of patients being significantly more prevalent in non-alcoholic steatohepatitis than in chronic viral hepatitis (41.3% vs. 5.1%, P < 0.001). In chronic viral hepatitis, cirrhosis (stages 5-6) was independently associated with increasing age, higher aspartate aminotransferase and gamma-glutamyl-transpeptidase levels, severe necroinflammation and metabolic syndrome (P = 0.016). In non-alcoholic steatohepatitis, severe fibrosis (stages 3-4) was independently associated with severe necroinflammation and metabolic syndrome (P = 0.033). Presence of metabolic syndrome was not associated with presence or severity of steatosis both in chronic viral hepatitis and in non-alcoholic steatohepatitis. CONCLUSION Metabolic syndrome is more prevalent in non-alcoholic steatohepatitis than in chronic viral hepatitis; it is associated independently with more severe fibrosis but not with the severity of steatosis, both in chronic viral hepatitis and in non-alcoholic steatohepatitis.


Hepatology | 2014

Cost‐effectiveness of noninvasive liver fibrosis tests for treatment decisions in patients with chronic hepatitis C

Emmanuel Tsochatzis; Catriona Crossan; Louise Longworth; Kurinchi Selvan Gurusamy; Manolo Rodriguez-Peralvarez; Konstantinos Mantzoukis; Julia O'Brien; Evangelos Thalassinos; Vassilios Papastergiou; Anna Noel-Storr; Brian Davidson; Andrew K. Burroughs

The cost‐effectiveness of noninvasive tests (NITs) as alternatives to liver biopsy is unknown. We compared the cost‐effectiveness of using NITs to inform treatment decisions in adult patients with chronic hepatitis C (CHC). We conducted a systematic review and meta‐analysis to calculate the diagnostic accuracy of various NITs using a bivariate random‐effects model. We constructed a probabilistic decision analytical model to estimate health care costs and outcomes (quality‐adjusted life‐years; QALYs) using data from the meta‐analysis, literature, and national UK data. We compared the cost‐effectiveness of four treatment strategies: testing with NITs and treating patients with fibrosis stage ≥F2; testing with liver biopsy and treating patients with ≥F2; treat none; and treat all irrespective of fibrosis. We compared all NITs and tested the cost‐effectiveness using current triple therapy with boceprevir or telaprevir, but also modeled new, more‐potent antivirals. Treating all patients without any previous NIT was the most effective strategy and had an incremental cost‐effectiveness ratio (ICER) of £9,204 per additional QALY gained. The exploratory analysis of currently licensed sofosbuvir treatment regimens found that treat all was cost‐effective, compared to using an NIT to decide on treatment, with an ICER of £16,028 per QALY gained. The exploratory analysis to assess the possible effect on results of new treatments, found that if SVR rates increased to >90% for genotypes 1‐4, the incremental treatment cost threshold for the “treat all” strategy to remain the most cost‐effective strategy would be £37,500. Above this threshold, the most cost‐effective option would be noninvasive testing with magnetic resonance elastography (ICER = £9,189). Conclusions: Treating all adult patients with CHC, irrespective of fibrosis stage, is the most cost‐effective strategy with currently available drugs in developed countries. (Hepatology 2014;60:832–843)


The American Journal of Gastroenterology | 2007

Hepatic Steatosis in Genotype 4 Chronic Hepatitis C Is Mainly Because of Metabolic Factors

Emmanuel Tsochatzis; George V. Papatheodoridis; Emanuel K. Manesis; N. Chrysanthos; Georgia Kafiri; Kalliopi Petraki; Emilia Hadziyannis; Helen Pandelidaki; Rodessa Zafiropoulou; Savvas Savvas; J. Koskinas; Athanasios J. Archimandritis

BACKGROUND/AIM:Hepatic steatosis is considered to be mostly associated with viral factors in genotype 3 and metabolic factors in genotype 1 chronic hepatitis C, while there are rather few data for genotype 4. We determined the parameters associated with steatosis in 350 chronic hepatitis C patients, focusing on genotype 4.METHODS:Histological lesions were evaluated according to Ishaks classification and steatosis was semiquantitatively graded. Several patient characteristics on the biopsy day were also evaluated.RESULTS:Steatosis was present in 73% of patients without significant differences among genotypes. Moderate/severe steatosis was more frequent in genotype 3 than 4 (44% vs 26%, P = 0.025) and similar between genotype 4 and 1 patients. Moderate/severe steatosis was associated with body mass index (BMI) in genotype 4 (P = 0.023) and gamma-glutamyl-transpeptidase in genotype 3 patients (P = 0.044). In 150 nondiabetic patients with BMI ≤25 kg/m2, moderate/severe steatosis was present in 15, 40, and 11% of genotype 1, 3, and 4 patients, respectively, (P = 0.005) and was independently associated only with genotype 3. In multivariate analysis, steatosis grade or moderate/severe steatosis was independently associated with higher BMI, genotype 3, and lower cholesterol.CONCLUSIONS:Moderate or severe steatosis is significantly less frequent in genotype 4 than 3 chronic hepatitis C patients and similar between genotype 4 and 1. In nondiabetic, nonoverweight patients, moderate or severe steatosis is present in only 10–15% of genotype 4 or 1 compared with 40% of genotype 3 patients. Thus, hepatic steatosis in genotype 4 is mostly associated with metabolic factors, similar to those in genotype 1.


Gut | 2007

Serum apoptotic caspase activity as a marker of severity in HBeAg-negative chronic hepatitis B virus infection

George V. Papatheodoridis; Emilia Hadziyannis; Emmanuel Tsochatzis; N. Chrysanthos; Anastasia Georgiou; Georgia Kafiri; Spilios Manolakopoulos; Dina Tiniakos; I Giannousis; E. K. Manesis; Athanasios J. Archimandritis

Background and aim: In chronic hepatitis C and non-alcoholic fatty liver disease, apoptotic caspases are activated in liver, and serum caspase activity has been suggested as a sensitive marker of early liver injury. An investigation was carried out into whether the serum levels of caspase-generated fragments of cytokeratin-18 (CK-18) are associated with the severity of liver lesions in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B virus (HBV) infection. Patients/methods: CK-18 fragment serum levels were determined in 115 treatment-naive, consecutive HBV patients and 30 healthy controls. Hepatic-expression of CK-18 fragments was evaluated by immunocytochemistry in chronic hepatitis B patients. Results: CK-18 fragment levels (U/l) were significantly lower in healthy controls (mean (SD), 154 (31)) than in 53 inactive carriers (172 (24), p = 0.003) and in 62 chronic hepatitis B patients (474 (488), p<0.001). The receiver operating characteristic curve showed excellent diagnostic accuracy (c-statistic: 0.87) for differentiating inactive carriers from chronic hepatitis B patients. A CK-18 fragment cut-off level of 240 U/l gave a sensitivity of 60%, and a specificity and positive predictive value of 100% for chronic hepatitis B diagnosis. CK-18 fragment levels were also lower in inactive carriers than in 16 chronic hepatitis B patients with transiently normal alanine aminotransferase (ALT; 327 (256), p = 0.001), offering good accuracy for such a differentiation (c-statistic: 0.78). In chronic hepatitis B patients, serum CK-18 fragments correlated positively with ALT/aspartate aminotransferase (AST), viraemia, grading score and their immunohistochemical hepatic expression, and negatively with platelet counts, but not with fibrosis or steatosis severity. Conclusions: Serum apoptotic caspase activity is strongly associated with the presence of liver injury in patients with HBeAg-negative chronic HBV infection. CK-18 fragment levels seem to be a very useful marker for differentiation between the inactive HBV carrier state and HBeAg-negative chronic hepatitis B, but not for estimation of the severity of liver histological lesions among HBeAg-negative chronic hepatitis B patients.


Journal of Clinical Gastroenterology | 2010

Serum apoptotic caspase activity in chronic hepatitis C and nonalcoholic Fatty liver disease.

George V. Papatheodoridis; Emilia Hadziyannis; Emmanuel Tsochatzis; Anastasia Georgiou; Georgia Kafiri; Dina Tiniakos; Katerina Margariti; Spilios Manolakopoulos; Emanuel K. Manesis; Athanasios J. Archimandritis

Background Apoptotic caspases are substantially activated in liver and serum caspase activity has been suggested as a marker of early liver injury. Aim To investigate whether serum levels of caspase-generated fragments of cytokeratin-18 are associated with the severity of histologic lesions in chronic hepatitis C virus (HCV) infection and nonalcoholic fatty liver disease (NAFLD). Methods We included 134 patients with chronic HCV infection and 58 patients with NAFLD, who consecutively underwent liver biopsy, and 40 healthy controls. Caspase-generated cytokeratin-18 fragment levels were blindly measured in stored serum samples. Results Median cytokeratin-18 fragment levels were lower in HCV-positive patients with minimal/mild than patients with moderate/severe histologic lesions (174 U/L vs. 223 U/L, P<0.001) offering moderate accuracy for differentiation between the 2 groups (c-statistic: 0.74). Cytokeratin-18 fragments levels were lower in healthy subjects (148 U/L) than patients with simple fatty liver (174 U/L, P=0.013) than patients with nonalcoholic steatohepatitis (355 U/L, P<0.001) offering excellent diagnostic accuracy for differentiation between the 2 latter groups (c-statistic: 0.87). Conclusions Serum apoptotic caspase activity is associated with the severity of liver histologic lesions in both chronic HCV infection and NAFLD, but it has excellent diagnostic accuracy in NAFLD and moderate accuracy in chronic HCV patients.


Scandinavian Journal of Gastroenterology | 2009

Smoking is associated with steatosis and severe fibrosis in chronic hepatitis C but not B

Emmanuel Tsochatzis; George V. Papatheodoridis; Spilios Manolakopoulos; Dina Tiniakos; E. K. Manesis; Athanasios J. Archimandritis

Objective. The results of retrospective studies suggest an association between smoking, insulin resistance, steatosis and fibrosis in patients with chronic hepatitis C (CHC); no data are available for chronic hepatitis B (CHB). The purpose of this study was to evaluate the relationship, if any, of such factors on liver fibrosis in a cohort of patients with CHB and CHC. Material and methods. The study prospectively included 271 consecutive patients with CHB (n=95) or CHC (n=176) who had undergone liver biopsies. Each patient completed a questionnaire on smoking habits; anthropometric measurements and laboratory examinations were carried out and histological lesions were recorded. Results. In CHC patients, severe fibrosis was independently associated with a higher body mass index (BMI) (OR: 1.180, 95% CI: 1.028–1.354; p=0.019), heavy smoking (OR: 3.923, 95% CI: 1.356–11.348; p=0.012), higher alanine aminotransferase (ALAT) levels (OR: 1.010, 95% CI: 1.003–1.017; p=0.005) and alkaline phosphatase (ALP) levels (OR: 1.016, 95% CI: 1.001–1.030; p=0.03) and presence of necroinflammation (OR: 11.165, 95% CI: 1.286–96.970; p=0.029). Moreover, steatosis was independently associated with high gamma-glutamyl transpeptidase (GGT) values, heavy smoking and presence of necroinflammation. In CHB patients, no association between smoking habits and fibrosis or steatosis was noted. Conclusions. Heavy smoking is associated with severe fibrosis in CHC but not CHB. Heavy smoking is also significantly associated with steatosis in CHC and this could be the link between smoking and fibrosis progression.

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Brian Davidson

University of Colorado Boulder

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Athanasios J. Archimandritis

National and Kapodistrian University of Athens

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George V. Papatheodoridis

National and Kapodistrian University of Athens

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