Browsing by Author "Bozkaya, Hakan"
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Item Anti-HDV immunoglobulin M testing in hepatitis delta revisited: Correlations with disease activity and response to pegylated interferon-alpha 2a treatment(Int Medical, 2012) Mederacke, Ingmar; Yurdaydın, Cihan; Dalekos, George N.; Bremer, Birgit; Erhardt, Andreas; Çakaloğlu, Yılmaz; Yalçın, Kendal; Zeuzem, Stefan; Zachou, Kalliopi; Bozkaya, Hakan; Dienes, Hans Peter; Manns, Michael P.; Wedemeyer, Heiner; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi/Gastroenteroloji Anabilim Dalı.; 7003706434Background: The role of anti-HDV immunoglobulin M (IgM) testing in patients receiving pegylated interferon-alpha therapy for hepatitis delta is unknown. We performed anti-HDV IgM testing in a well defined cohort of HDVinfected patients who were treated with pegylated interferon-alpha 2a plus adefovir, or either drug alone. Methods: Sera from 33 HDV-RNA-positive patients from the international HIDIT-1 trial were available for anti-HDV IgM testing (ETI-DELTA-IGMK-2 assay, DiaSorin, Saluggia, Italy) before therapy, at treatment weeks 24 and 48, and at 24 weeks after the end of treatment. Results: Anti-HDV IgM tested positive in 31 out of the 33 patients (94%) prior to treatment. HDV IgM levels correlated with histological inflammatory activity (r= 0.51, P<0.01) and were higher in patients with alanine aminotransferase and gamma-glutamyl transpeptidase levels above the median (P<0.05). Quantitative anti-HDV IgM values declined in patients responding to antiviral therapy, however anti-HDV IgM remained positive after treatment in the majority of virological responders. Conclusions: We suggest that anti-HDV IgM testing might give additional useful information to determine disease activity in hepatitis delta and to predict treatment response to antiviral therapy with type I interferons. However, determination of anti-HDV IgM can not substitute HDV RNA testing, which remains the primary virological marker for response to therapy.Item Association between level of hepatitis d virus RNA at week 24 of pegylated interferon therapy and outcome(Elsevier, 2015-12) Keskin, Onur; Wedemeyer, Heiner; Tüzün, Ali; Zachou, Kalliopi; Deda, Xheni; Dalekos, George N.; Heidrich, Benjamin; Pehlivan, Selcen; Zeuzem, Stefan; Yalçın, Kendal; Tabak, Fehmi; İdilman, Ramazan; Bozkaya, Hakan; Manns, Michael; Yurdaydın, Cihan; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi/Gastroenteroloji Anabilim Dalı.; 7003706434BACKGROUND & AIMS: Interferon is the only effective treatment for chronic hepatitis D virus (HDV) infection. No rules have been set for stopping treatment based on viral kinetics. We analyzed data from an international study of hepatitis D treatment to identify factors associated with outcomes of pegylated interferon treatment, with and without adefovir. METHODS: We analyzed data from the Hep-Net-International Delta Hepatitis Intervention Trial on 50 patients with compensated liver disease who tested positive for anti-HDV and HDV RNA. Subjects received pegylated interferon alpha 2a, with adefovir or placebo, or only adefovir, for 48 weeks. Twenty-four weeks after treatment ended, 41 patients were evaluated for levels of HDV RNA and DNA, liver enzymes, and hepatitis B surface antigen (HBsAg); liver biopsy specimens were analyzed for fibrosis. Response to therapy was defined as end-of-treatment response or post-treatment week 24 virologic response. In both cases virologic response was associated with undetectable HDV RNA levels. Patients with less than a 1 log decrease in HDV RNA at the end of treatment were considered null responders. RESULTS: Based on univariate and multivariate analysis, the level of HDV RNA at week 24 of treatment was associated more strongly with response to therapy than other factors analyzed. The level of HBsAg at week 24 of treatment was associated with a response to therapy only in univariate analysis. Lack of HDV RNA at week 24 of treatment, or end of treatment, identified responders with positive predicted values of 71% and 100%, respectively. At 24 weeks after treatment, a decrease in HDV RNA level of less than 1 log, combined with no decrease in HBsAg level, identified null responders with a positive predictive value of 83%. A decrease in HDV RNA level of more than 2 log at week 24 of treatment identified null responders with a negative predictive value of 95%. CONCLUSIONS: Based on an analysis of data from a large clinical trial, the level of HDV RNA at week 24 of treatment with pegylated interferon, with or without adefovir for 48 weeks, can identify patients who will test negative for HDV RNA 24 weeks after the end of treatment. This information can be used to help physicians manage patients receiving therapy for chronic hepatitis D.Item Efficacy of pegylated interferon-based treatment in patients with cirrhosis due to chronic delta hepatitis: Comparison with non-cirrhotic patients(Wiley, 2009-10) Yurdaydın, Cihan; Kobacam, Gökhan; Cakaloğlu, Yılmaz; Erhardt, Andreas; Değertekin, Halil; Zeuzem, Stefan; Dalekos, George N.; Bozkaya, Hakan; Dienes, Hans P.; Manns, Michael P.; Wedemeyer, Heiner; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi/İç Hastalıkları Anabilim Dalı/Gastroenteroloji Bilimdalı.Item Famciclovir treatment of chronic delta hepatitis(Elsevier Science BV, 2002-08) Bozkaya, Hakan; Yurdaydın, Cihan; Tillmann, Hans L.; Aslan, Nuray; Okçu, A. Heper; Erden, Esra; Yalçın, Kendal; Ilıman, Nevzat; Uzunalimoğlu, Özden; Manns, Michael P.; Bozdayı, Abdurrahman Mithat; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi/İç Hastalıkları Anabilim Dalı/Gastroentoloji Bilim Dalı.Background/Aims: Interferon is the only established therapy for chronic delta hepatitis and alternative treatment options are an urgent need. Since successful treatment of a case of post-transplant delta hepatitis with the nucleoside analogue famciclovir had been reported, a pilot study was undertaken to evaluate the use of famciclovir in the treatment of chronic delta hepatitis. Methods: A total of 15 adult patients, 13 men, two women, ages 20-52 years, with chronic delta hepatitis were treated with famciclovir, 500 mg, three times a day for 6 months and were then followed-up for 6 months posttreatment. All patients had compensated chronic liver disease, elevated liver enzymes and were hepatitis delta virus (HDV) RNA positive by polymerase chain reaction at baseline. Patients were monitored and tested for HBsAg, hepatitis B virus (HBV) DNA and HDV RNA levels. Liver biopsies were obtained before starting famciclovir and within I month of completion of treatment. Results: HBV DNA levels decreased in nine of the 15 patients and levels rose again after treatment (P < 0.05). Famciclovir had no effect on alanine aminotransferase (ALT) and HBsAg levels or on serum HDV RNA and overall, there was no improvement in liver histology. Conclusions: Treatment of chronic delta hepatitis with famciclovir has no effect on disease activity and HDV RNA levels.Item A multicenter randomised study comparing the efficacy of pegylated interferon-alfa-2a plus adevofir dipivoxil vs. pegylated interferon-alfa-2a plus placebo vs. adevofir dipivoxil for the treatment of chronic delta hepatitis: The hep-net/international delta hepatitis intervention trial (HID-IT)(Wiley, 2006-10) Yurdaydın, Cihan; Wedemeyer, Heiner; Dalekos, George; Erhardt, Alexander; Çakaloğlu, Y.; Değertekin, H.; Zeuzem, Stefan; Zachou, Kalliopi; Bozkaya, Hakan; Gürel, S.; Uludağ Üniversitesi/Tıp Fakültesi/İç Hastalıkları Anabilim Dalı/Gastroenteroloji Bilim Dalı.Item Peginterferon plus adefovir versus either drug alone for hepatitis delta(Massachusetts Medical Soc, 2011-01-27) Wedemeyer, Heiner; Yurdaydın, Cihan; Dalekos, George N.; Erhardt, Andreas; Çakaloğlu, Yılmaz; Değertekin, Halil; Zeuzern, Stefan; Zachou, Kalliopi; Bozkaya, Hakan; Koch, Armin; Bock, Thomas; Dienes, Hans Peter; Manns, Michael P.; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi.; 7003706434BACKGROUND 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 mu g of peginterferon alfa-2a weekly plus 10 mg of adefovir daily, 29 received 180 mu g 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.Item Quantitative HBsAg and HDV-RNA levels in chronic delta hepatitis(Wiley, 2010-03) Zachou, Kalliopi; Yurdaydın, Cihan; Drebber, Uta; Dalekos, George Nikolaos; Erhardt, Andreas; Çakaloğlu, Yılmaz; Değertekin, Halil; Zeuzem, Stefan S.; Bozkaya, Hakan; Schlaphoff, Verena; Dienes, Hans Peter; Bock, C. Thomas; Manns, Michael Peter; Wedemeyer, Heiner; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi/İç Hastalıkları Anabilim Dalı.; 7003706434Background: Hepatitis delta virus (HDV) causes severe liver disease. Aims: To investigate the quantitative HDV-RNA, HBsAg and hepatitis B virus (HBV)DNA levels in correlation to histological, biochemical and demographical parameters in patients with chronic HDV infection as similar data in a large series of HDV patients are missing. Methods: Eighty HDV patients were recruited in Germany, Turkey and Greece; quantitative determination of HDV-RNA, HBsAg and HBV-DNA was performed by real-time polymerase chain reaction, the Architect HBsAg assay and Cobas TaqMan HBV test respectively. Results: All patients were infected with HDV-genotype 1. Thirty-five patients (48%) had significant fibrosis (Ishak 3-4) and 15 (20.5%) had cirrhosis. HDV viraemia ranged from 1.1 x 10(3) to 8.4 x 10(7) copies/ml with 60% of patients showing HDV-RNA levels above 105 copies/ml accompanied by low HBV viraemia (<10(5) copies/ml). However, HDV-RNA and HBV-DNA levels showed no direct inverse correlation. HDV-RNA correlated positively with HBsAg and negatively with age. HBsAg correlated negatively with age and positively with histological grading. Only gamma-glutamyltranspeptidase was independently associated with cirrhosis (P=0.032), while no biochemical parameter was associated with grading. Conclusions: (i) HBsAg levels correlated with HDV viraemia in chronic HDV. (ii) Biochemical parameters did not accurately indicate the stage and grade of liver disease in chronic HDV and thus liver biopsy seems to remain the major tool for the evaluation of delta hepatitis patients.Item Renal function during treatment with adefovir plus peginterferon alfa-2a vs either drug alone in hepatitis B/D co-infection(Wiley, 2012-06) Mederacke, Ingmar; Yurdaydın, Cihan; Grosshennig, Anika; Erhardt, Andreas; Çakaloğlu, Yılmaz; Yalçın, Kendal; Zeuzem, Stefan; Zachou, Kalliopi; Chatzikyrkou, Christos; Bozkaya, Hakan; Dalekos, George Nikolaos; Manns, Michael Peter; Wedemeyer, Heiner; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi.; 7003706434Long-term safety of treatment with hepatitis B virus (HBV) polymerase inhibitors is a concern. Adefovir dipivoxil (ADV) therapy has previously been associated with impairment of renal function. Limited data are available on the safety of combination therapy with nucleos(t)ide analogues and interferon alfa (IFNa). The aim of this analysis was to assess the renal function during combination therapy with peginterferon alfa-2a (PegIFNa-2a) plus ADV vs either drug alone in patients with hepatitis B/D co-infection. We performed a retrospective analysis of renal function data of patients treated in the Hep-Net/International Delta Hepatitis Intervention Trial 1(HIDIT-1-trial), a European multicenter study to investigate the efficacy of 48 weeks of therapy with PegIFNa-2a+ADV vs either drug alone in 90 patients with chronic hepatitis B/D co-infection. Glomerular filtration rates (GFR) were calculated by CockcroftGault (CG), abbreviated Modification of Diet in Renal Disease (MDRD) study and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. After 48 weeks of therapy GFR values were significantly lower in patients receiving adefovir-containing treatment vs PegIFNa-2a alone [mean difference 16.1 mL/min (CG) and 10.2 mL/min (MDRD), respectively, P < 0.05] while no differences were observed between patients receiving adefovir alone vs combination treatment. Twenty-four weeks after treatment GFR values did not differ between treatment arms. A decrease in GFR =20% was observed more often in patients during adefovir-containing treatment vs PegIFNa-2a alone (P < 0.05) which was confirmed by KaplanMeier analysis. Adefovir-containing but not PegIFNa-2a treatment was associated with a decrease in GFR values in about one-fifth of patients. Combination treatment of PegIFNa-2a+ADV in chronic hepatitis B/D co-infection did not lead to any further impairment of kidney function.Item Screening for hemochromatosis in Turkey(Springer, 2004-03) Bozkaya, Hakan; Bektaş, Mehmet; Metin, Olga; Erkan, Özlem E.; İbrahimoğlu, Dicle; Dalva, Klara; Akbıyık, Filiz; Bozdayı, Abdurrahman Mithat; Akay, Cemal; Yurdaydın, Cihan; Aslan, Önder; Uzunalimoğlu, Özden; Gürel, Selim; Uludağ Üniversitesi/Tıp Fakültesi/Gastroenteroloji Bilim Dalı.; 7003706434In this study we screened 3060 consecutive blood donors for an unbound iron-binding capacity level of <28 mu M and then performed HFE mutation analysis in these subjects. Sixty-five of the 75 subjects with a low initial unbound iron-binding capacity (all had normal ferritin levels) came back and only 5 (8%) had a low fasting unbound iron-binding capacity. Mutational analysis revealed H63D heterozygosity in two of five subjects. Four of five subjects had liver biopsy indication and none had increased liver iron. HFE genotyping of 60 subjects with a low initial but normal fasting unbound iron-binding capacity revealed heterozygote H63D in seven (11.6%). No allelic variant of position 282 or 63 was found in three previously diagnosed patients with hereditary hemochromatosis. In conclusion, full phenotypic expression of hereditary hemochromatosis is very rare in Turkey. The absence of HFE mutations in three patients with hereditary hemochromatosis suggests that hereditary hemochromatosis in Turkey occurs without common HFE mutations.