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Featured researches published by Kalliopi Zachou.


The New England Journal of Medicine | 2011

Peginterferon plus Adefovir versus Either Drug Alone for Hepatitis Delta

Heiner Wedemeyer; Cihan Yurdaydin; George N. Dalekos; A. Erhardt; Yilmaz Cakaloglu; Halil Degertekin; Selim Gurel; Stefan Zeuzem; Kalliopi Zachou; Hakan Bozkaya; Armin Koch; Thomas Bock; Hans Peter Dienes; Michael P. Manns

BACKGROUND Chronic infection with hepatitis B virus and hepatitis delta virus (HDV) results in the most severe form of viral hepatitis. There is no currently approved treatment. We investigated the safety and efficacy of 48 weeks of treatment with peginterferon alfa-2a plus adefovir dipivoxil, peginterferon alfa-2a alone, and adefovir dipivoxil alone. METHODS We conducted a randomized trial in which 31 patients with HDV infection received treatment with 180 μg of peginterferon alfa-2a weekly plus 10 mg of adefovir daily, 29 received 180 μg of peginterferon alfa-2a weekly plus placebo, and 30 received 10 mg of adefovir alone weekly for 48 weeks. Follow-up was conducted for an additional 24 weeks. Efficacy end points included clearance of HDV RNA, normalization of alanine aminotransferase levels, and a decline in levels of hepatitis B surface antigen (HBsAg). RESULTS The primary end point--normalization of alanine aminotransferase levels and clearance of HDV RNA at week 48--was achieved in two patients in the group receiving peginterferon alfa-2a plus adefovir and two patients in the group receiving peginterferon alfa-2a plus placebo but in none of the patients in the group receiving adefovir alone. At week 48, the test for HDV RNA was negative in 23% of patients in the first group, 24% of patients in the second, and none of those in the third (P = 0.006 for the comparison of the first and third groups; P = 0.004 for the comparison of the second and third). The efficacy of peginterferon alfa-2a was sustained for 24 weeks after treatment, with 28% of the patients receiving peginterferon alfa-2a plus adefovir or peginterferon alfa-2a alone having negative results on HDV-RNA tests; none of the patients receiving adefovir alone had negative results. A decline in HBsAg levels of more than 1 log(10) IU per milliliter from baseline to week 48 was observed in 10 patients in the first group, 2 in the second, and none in the third (P<0.001 for the comparison of the first and third groups and P = 0.01 for the comparison of the first and second). CONCLUSIONS Treatment with peginterferon alfa-2a for 48 weeks, with or without adefovir, resulted in sustained HDV RNA clearance in about one quarter of patients with HDV infection. (Current Controlled Trials number, ISRCTN83587695.).


Journal of Autoimmune Diseases | 2004

Autoantibodies and autoantigens in autoimmune hepatitis: important tools in clinical practice and to study pathogenesis of the disease

Kalliopi Zachou; Eirini I. Rigopoulou; George N. Dalekos

Autoimmune hepatitis (AIH) is a chronic necroinflammatory disease of the liver characterized by hypergammaglobulinemia, characteristic autoantibodies, association with HLA DR3 or DR4 and a favorable response to immunosuppressive treatment. The etiology is unknown. The detection of non-organ and liver-related autoantibodies remains the hallmark for the diagnosis of the disease in the absence of viral, metabolic, genetic, and toxic etiology of chronic hepatitis or hepatic injury. The current classification of AIH and the several autoantibodies/target-autoantigens found in this disease are reported. Current aspects on the significance of these markers in the differential diagnosis and the study of pathogenesis of AIH are also stated. AIH is subdivided into two major types; AIH type 1 (AIH-1) and type 2 (AIH-2). AIH-1 is characterized by the detection of smooth muscle autoantibodies (SMA) and/or antinuclear antibodies (ANA). Determination of antineutrophil cytoplasmic autoantibodies (ANCA), antibodies against the asialoglycoprotein receptor (anti-ASGP-R) and antibodies against to soluble liver antigens or liver-pancreas (anti-SLA/LP) may be useful for the identification of patients who are seronegative for ANA/SMA. AIH-2 is characterized by the presence of specific autoantibodies against liver and kidney microsomal antigens (anti-LKM type 1 or infrequently anti-LKM type 3) and/or autoantibodies against liver cytosol 1 antigen (anti-LC1). Anti-LKM-1 and anti-LKM-3 autoantibodies are also detected in some patients with chronic hepatitis C (HCV) and chronic hepatitis D (HDV). Cytochrome P450 2D6 (CYP2D6) has been documented as the major target-autoantigen of anti-LKM-1 autoantibodies in both AIH-2 and HCV infection. Recent convincing data demonstrated the expression of CYP2D6 on the surface of hepatocytes suggesting a pathogenetic role of anti-LKM-1 autoantibodies for the liver damage. Family 1 of UDP-glycuronosyltransferases has been identified as the target-autoantigen of anti-LKM-3. For these reasons the distinction between AIH and chronic viral hepatitis (especially of HCV) is of particular importance. Recently, the molecular target of anti-SLA/LP and anti-LC1 autoantibodies were identified as a 50 kDa UGA-suppressor tRNA-associated protein and a liver specific enzyme, the formiminotransferase cyclodeaminase, respectively. Anti-ASGP-R and anti-LC1 autoantibodies appear to correlate closely with disease severity and response to treatment suggesting a pathogenetic role of these autoantibodies for the hepatocellular injury. In general however, autoantibodies should not be used to monitor treatment, predict AIH activity or outcome. Finally, the current aspects on a specific form of AIH that may develop in some patients with a rare genetic syndrome, the autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome (APECED) are also given. Autoantibodies against liver microsomes (anti-LM) are the specific autoantibodies detected in AIH as a disease component of APECED but also in cases of dihydralazine-induced hepatitis. Cytochrome P450 1A2 has been identified as the target-autoantigen of anti-LM autoantibodies in both APECED-related AIH and dihydralazine-induced hepatitis. The latter may indicate that similar autoimmune pathogenetic mechanisms can lead to liver injury in susceptible individuals irrespective of the primary defect. Characterization of the autoantigen-autoantibody repertoire continues to be an attractive and important tool to get access to the correct diagnosis and to gain insight into the as yet unresolved mystery of how hepatic tolerance is given up and AIH ensues.


Gut | 2005

Prevalence and clinical significance of isotype specific antinuclear antibodies in primary biliary cirrhosis.

Eirini I. Rigopoulou; E T Davies; Albert Parés; Kalliopi Zachou; Christos Liaskos; D.P. Bogdanos; Juan Rodés; George N. Dalekos; Diego Vergani

Background: Antinuclear antibodies (ANA) giving a rim-like/membranous (RL/M) or a multiple nuclear dot (MND) pattern are highly specific for primary biliary cirrhosis (PBC). Aim and subjects: To assess the prevalence of PBC specific ANAs, their Ig isotype, and their clinical significance in 90 PBC patients from Greece and Spain. Twenty eight patients with chronic hepatitis C, 23 patients with systemic lupus erythematosus, and 17 healthy subjects were studied as controls. Methods: PBC specific ANA reactivity was tested by indirect immunofluorescence using HEp2 cells as substrate and individual Ig class (IgG, IgA, IgM) and IgG subclass (IgG1, IgG2, IgG3, IgG4) specific antisera as revealing reagents. Results: Fourteen of 90 (15.6%) PBC patients had PBC specific ANA reactivity when an anti-IgG (total) antiserum was used as the revealing reagent while 58 (64.4%) were positive when specific antisera to each of the four IgG isotypes were used. The prevailing isotype was IgG3 for MND and IgG1 for RL/M. PBC patients with specific ANA, in particular of the IgG3 isotype, had significantly more severe biochemical and histological disease compared with those who were seronegative. None of the controls was positive. Conclusions: Disease specific ANA are present in the majority of patients with PBC when investigated at the level of immunoglobulin isotype. PBC specific ANA, in particular of the IgG3 isotype, are associated with a more severe disease course, possibly reflecting the peculiar ability of this isotype to engage mediators of damage.


Journal of Hepatology | 2011

Mycophenolate for the treatment of autoimmune hepatitis: prospective assessment of its efficacy and safety for induction and maintenance of remission in a large cohort of treatment-naïve patients.

Kalliopi Zachou; Nikolaos K. Gatselis; Georgia Papadamou; Eirini I. Rigopoulou; George N. Dalekos

BACKGROUND & AIMS Standard therapy for autoimmune hepatitis (AIH) is corticosteroids with or without azathioprine. However, 20% of patients do not respond or are intolerant to conventional treatment. Therefore, we evaluated prospectively the efficacy and safety of mycophenolate mofetil (MMF) in inducing and/or maintaining remission in treatment-naïve AIH patients. METHODS Fifty-nine treatment-naïve patients with well defined AIH were treated with prednisolone plus 1.5-2g/d of MMF. Patients were candidates for MMF withdrawal after at least 4 years. Treatment outcomes were defined according to the International Autoimmune Hepatitis Group report. RESULTS Treatment duration with MMF was 26months (range 3-92). Eighty-eight percent (52/59) of patients responded initially clinically and biochemically (normalization of transaminases and γ-globulins) most of them within 3months. The remaining 7 patients (12%) had partial response. In total, 59.3% (35/59) of patients had complete response (CR) with 37% (22/59) of them having achieved CR off prednisolone, while 28.8% (17/59) had initial CR with relapses. No patient was non-responder. Prednisolone withdrew in 57.6% (34/59) of patients in 8months. The only independent predictor of treatment outcome, was γ-GT (baseline γ-GT, p=0.008 and γ-GT on month 24, p<0.05). Severe side effects leading to MMF discontinuation occurred in only 3.4% (2/59) of patients. Six patients (2 according to protocol and 4 for personal reasons), stopped treatment with MMF, but 3 relapsed. CONCLUSIONS MMF seems safe and effective as first-line therapy in inducing and maintaining remission in treatment-naive patients with AIH, having a significant and rapid steroid sparing effect as attested by the fact that so far, 37% (22/59) of AIH patients achieved CR off prednisolone.


Hepatology | 2014

Late HDV RNA relapse after peginterferon alpha-based therapy of chronic hepatitis delta

B. Heidrich; Cihan Yurdaydin; Gökhan Kabaçam; Boris A. Ratsch; Kalliopi Zachou; B. Bremer; George N. Dalekos; A. Erhardt; Fehmi Tabak; Kendal Yalçin; Selim Gurel; Stefan Zeuzem; Markus Cornberg; C.-Thomas Bock; Michael P. Manns; Heiner Wedemeyer

Interferon alpha is the only treatment option for hepatitis delta virus (HDV). Trials investigating the efficacy of pegylated interferon alpha (PEG‐IFNa) showed HDV RNA negativity rates of 25‐30% 24 weeks after therapy. However, the clinical and virological long‐term outcome of HDV‐infected patients treated with PEG‐IFNa is unknown. We performed a retrospective‐prospective follow‐up of 77 patients treated for 48 weeks with either PEG‐alfa‐2a and adefovir (ADV) or either drug alone in the Hep‐Net‐International‐Delta‐Hepatitis‐Intervention‐Study 1 (HIDIT‐1) trial. Long‐term follow‐up data were available for 58 out of 77 patients (75%) with a median time of follow‐up of 4.5 (0.5‐5.5) years and a median 3 visits per patient. Patients treated with ADV alone received retreatment with PEG‐IFNa (48% versus 19%; P = 0.02) more often. Hepatitis B virus surface antigen (HBsAg) became negative in six PEG‐IFNa‐treated patients until the end of long‐term follow‐up (10%). Sixteen patients tested HDV RNA‐negative 6 months after PEG‐IFNa treatment who were entered in the long‐term follow‐up study. Out of these, nine individuals tested HDV RNA‐positive at least once during further long‐term follow‐up, with seven patients being HDV RNA‐positive at the most recent visit. Clinical endpoints (liver‐related death, liver transplantation, hepatic decompensation, hepatocellular carcinoma) were observed in three PEG‐IFNa‐treated (8%) and three ADV‐treated (14%) patients during posttreatment long‐term follow‐up with an overall annual event rate of 2.5% (4.9% in cirrhosis). Sequencing confirmed the reappearance of pretreatment virus strains in all cases. Conclusion: Late HDV RNA relapses may occur after PEG‐IFNa therapy of hepatitis delta and thus the term sustained virological response should be avoided in HDV infection. The annual posttreatment rate of clinical events in hepatitis delta patients eligible for PEG‐IFNa therapy is about 2.5% and 4.9% in patients with cirrhosis. (Hepatology 2014;60:87‐97)


European Journal of Internal Medicine | 2002

Autoantibodies and defined target autoantigens in autoimmune hepatitis: an overview

Georgios N. Dalekos; Kalliopi Zachou; Christos Liaskos; Nikolaos K. Gatselis

Autoimmune hepatitis (AIH) is a disease of unknown aetiology characterised by hypergammaglobulinaemia, non-organ and liver-related autoantibodies, association with HLA-DR3 or DR4 and a favourable response to immunosuppression. The current classification of AIH and the several autoantibodies/target autoantigens found in this disease are reported. The importance of these markers in the differential diagnosis and the study of pathogenesis of AIH is also given. AIH is subdivided into two major types: AIH type 1 (AIH-1) and AIH type 2 (AIH-2). AIH-1 is characterised by the detection of smooth muscle autoantibodies (SMA) and/or antinuclear antibodies (ANA). Antineutrophil cytoplasmic autoantibodies (ANCA), in most cases of perinuclear pattern (p-ANCA), by the indirect immunofluorescence assay, antibodies against the asialoglycoprotein receptor (anti-ASGP-R) and antibodies to soluble liver antigens or liver-pancreas (anti-SLA/LP) may be useful for the identification of individuals who are seronegative for ANA/SMA. AIH-2 is characterised by the presence of specific autoantibodies against liver and kidney microsomal antigens (anti-LKM type 1 or infrequently anti-LKM type 3) and/or autoantibodies against liver cytosol 1 antigen (anti-LC1). Anti-LKM-1 and anti-LKM-3 autoantibodies are also detected in some patients with chronic hepatitis C (HCV) and chronic hepatitis D (HDV). For these reasons, the distinction between AIH and chronic viral hepatitis is of particular importance. Cytochrome P450 2D6 (CYP2D6) is the major target autoantigen of anti-LKM-1 autoantibodies in both conditions (AIH-2 and HCV infection). Recent data have demonstrated the expression of CYP2D6 on the surface of hepatocytes, suggesting a pathogenetic role of anti-LKM-1 autoantibodies in liver injury. Family 1 of UDP-glycuronosyltransferases has been identified as the target autoantigen of anti-LKM-3. The molecular target of anti-SLA/LP autoantibodies has been identified recently as a 50 kDa protein with unknown structure and function. A liver-specific enzyme, the formiminotransferase cyclodeaminase, was identified as the target autoantigen of anti-LC1 autoantibodies. Anti-ASGP-R and anti-LC1 autoantibodies appear to correlate better with the severity of AIH and the response to treatment. The latter may suggest a pathogenic role of these autoantibodies in the hepatocellular damage in AIH. In general, however, autoantibodies should not be used to monitor treatment or to predict AIH activity or outcome. Finally, current knowledge concerning a specific form of AIH that may develop in some patients with a rare genetic syndrome, the autoimmune polyglandular syndrome type-1 (APS-1), is also discussed. Autoantibodies against liver microsomes (anti-LM) are the specific autoantibodies found in AIH as a disease component of APS-1. However, anti-LM autoantibodies have also been described in cases of dihydralazine-induced hepatitis. Cytochrome P450 1A2 has been identified as the target autoantigen of anti-LM autoantibodies in both disease entities.


Liver International | 2010

Quantitative HBsAg and HDV-RNA levels in chronic delta hepatitis.

Kalliopi Zachou; Cihan Yurdaydin; Uta Drebber; George N. Dalekos; A. Erhardt; Yilmaz Cakaloglu; Halil Degertekin; Selim Gurel; Stefan Zeuzem; Hakan Bozkaya; Verena Schlaphoff; Hans Peter Dienes; Thomas Bock; Michael P. Manns; Heiner Wedemeyer

Background: Hepatitis delta virus (HDV) causes severe liver disease.


Journal of Viral Hepatitis | 2004

Occult hepatitis B virus infection in Greek patients with chronic hepatitis C and in patients with diverse nonviral hepatic diseases

S. P. Georgiadou; Kalliopi Zachou; Eirini I. Rigopoulou; C. Liaskos; P. Mina; F. Gerovasilis; E. Makri; Georgios N. Dalekos

Summary.  Occult hepatitis B virus (HBV) infection has been reported in patients with chronic hepatitis C who are negative for HBV surface antigen (HBsAg). However, the significance of ‘silent’ HBV in hepatitis C virus (HCV) infection is unknown. We investigated 540 subjects for the presence of occult HBV in Greek HCV patients, patients with nonviral liver diseases and healthy donors in an attempt to determine the frequency and importance of this phenomenon. One hundred and eighty‐seven anti‐HCV(+)/HBsAg(−) patients’ sera were investigated for the presence of HBV‐DNA by polymerase chain reaction. Two hundred and eighty‐two selected blood donors (positive for antibodies to HBV core antigen) and 71 patients with various nonviral hepatic diseases consisted the control groups [both controls were anti‐HCV(−)/HBsAg(−)]. HBV‐DNA was detected in 26.2% of HCV‐infected patients vs 8.5% of patients with nonviral diseases (P = 0.003) and 0/282 of donors (P = 0.0000). HBV‐DNA was neither associated with HBV markers, nor with the clinical status of HCV and nonHCV patients. Neither epidemiological, histologic and virologic data nor the response to therapy were associated with the HBV‐DNA detection. Hence one quarter of HCV‐infected patients had occult HBV infection. Similar findings were not found in both control groups. Occult HBV infection in Greek patients with chronic hepatitis C does not seem to modify the progression of chronic liver disease. Further studies of longer duration are needed in order to clarify the role of ‘silent’ HBV infection in HCV‐infected patients.


Liver International | 2012

Management of severe acute to fulminant hepatitis B: to treat or not to treat or when to treat?

Hans L. Tillmann; Kalliopi Zachou; George N. Dalekos

Despite a decline in cases of acute hepatitis B and the low hepatitis B virus (HBV) chronicity rates in adults, still some patients progress to HBV‐related fulminant liver failure. In this review, we discuss treatment options that may prevent the progression of severe acute hepatitis B to fulminant liver failure and death. In severe acute HBV with prolonged prothrombin time and increased bilirubin, interferon failed to be effective while antiviral treatment, particularly with lamivudine, appears to improve survival (mean survival almost 80%). Outcome without antiviral therapy has remained considerably poor, whereas there is no convincing evidence of amelioration of HBV‐targeted immunity. Of note, most patients who died or required transplantation despite lamivudine therapy, were started on lamivudine at advanced stages compared with those survived. This suggests that prompt and timely antiviral therapy is crucial. Owing to the abovementioned results the design of randomized placebo‐control trials in the setting of severe acute hepatitis B seems unethical. On the contrary, the design of multicentre double‐blind randomized trials to compare the efficacy between lamivudine and entecavir or even tenofovir in acute severe HBV cases is ideally needed, but these studies appear to be very difficult to perform considering that these cases are not frequent and therefore, it is almost impossible to have two arms adequately numerous and homogenous for statistical evaluation. Thus, in the absence of solid evidence based data, the hepatologists could treat their patients with severe acute hepatitis B with lamivudine or the most potent antivirals entecavir or tenofovir.


European Journal of Gastroenterology & Hepatology | 2002

Increased incidence of anti-LKM autoantibodies in a consecutive cohort of hepatitis C patients from central Greece.

Georgios N. Dalekos; Eirini Makri; Stephanie Loges; Petra Obermayer-Straub; Kalliopi Zachou; Thomas Tsikrikas; Elenore Schmidt; Georgia Papadamou; Michael P. Manns

Objectives In Greece, there are insufficient data regarding the presence of non-organ and liver-related autoantibodies in hepatitis C patients. This study in a consecutive cohort of 39 such patients from central Greece investigates (1) the prevalence of non-organ and liver-related autoantibodies, and (2) the reactivity of anti-liver–kidney microsomal type 1 antibodies (in the case of positivity with at least one of the methods used) against their molecularly defined antigens. Design All serum samples were tested by standard and molecular assays for the presence of anti-nuclear antibodies, smooth muscle antibodies, anti-liver–kidney microsomal type 1 antibodies, antibodies against parietal cells, anti-CYP2A6, anti-CYP1A2 and anti-CYP2D6 autoantibodies. Methods Indirect immunofluorescence, competitive enzyme-linked immunosorbent assays, immunoblotting and novel radioligand assays based on immunoprecipitation of [35S]-methionine labelled recombinant CYP2A6, CYP1A2 and CYP2D6 His-taq fusion proteins produced by in vitro transcription/translation were used. Results Seven out of 39 patients (17.9%) tested positive for smooth muscle antibodies, 2/39 (5.1%) tested positive for anti-nuclear antibodies, 1/39 (2.5%) tested positive for parietal cell antibodies, and 4/39 (10.3%) were found to be anti-liver–kidney microsomal positive (with at least one of the methods used). All sera were negative for anti-CYP2A6 and anti-CYP1A2 autoantibodies. Three out of four anti-liver–kidney microsomal positive samples had the typical liver–kidney microsomal staining pattern shown by indirect immunofluorescence. However, none tested positive for anti-CYP2D6 autoantibodies using the competitive CYP2D6 enzyme-linked immunosorbent assay, the specific CYP2D6 radioligand assay, and western blot using either human microsomes or recombinant CYP2D6. The fourth patient tested negative for anti-liver–kidney autoantibodies by either indirect immunofluorescence or the competitive enzyme-linked immunosorbent assay, but was repeatedly positive for anti-CYP2D6 autoantibodies by the sensitive and specific radioligand assay. Western blot experiments using human microsomes in this patient serum revealed two bands of 50 kDa and 55 kDa that documented as anti-CYP2D6 and anti-uridine triphosphate glucuronosyltransferase autoantibodies when recombinant CYP2D6 and recombinant uridine triphosphate glucuronosyltransferase autoantigens were used for immunoblot, respectively. Conclusions A relatively high incidence of anti-liver–kidney microsomal autoantibodies (10.3%) was found in a consecutive sample of Greek patients with hepatitis C. The expanded panel of assays, however, failed to document CYP2D6 as the target autoantigen of anti-liver–kidney microsomal autoantibodies in most patients. We report for the first time the detection of parietal cell antibodies and both anti-CYP2D6 (anti-liver–kidney microsomal type 1) and anti-uridine triphosphate glucuronosyltransferase (anti-liver–kidney microsomal type 3) autoantibodies in patients who were hepatitis C positive/hepatitis D negative. Further studies are needed to confirm our findings and to determine whether these preliminary results have a clinical importance or not.

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