Hülya Çetinkaya
Ankara University
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Featured researches published by Hülya Çetinkaya.
Journal of Viral Hepatitis | 2008
Cihan Yurdaydin; Hakan Bozkaya; Fatih Oguz Onder; H. Şentürk; H. Karaaslan; Meral Akdogan; Hülya Çetinkaya; Esra Erden; Ö. Erkan-Esin; K. Yalçın; A.M. Bozdayi; Raymond F. Schinazi; J. L. Gerin; Ozden Uzunalimoglu; Ali Özden
Summary. Chronic delta hepatitis is the most severe form of chronic viral hepatitis for which interferon (IFN) is the only available treatment. In 39 patients (25 were treatment‐naïve, 14 had previously used IFN), efficacy of 1‐year treatment with IFN (9 MU, t.i.w.) or lamivudine (LAM; 100 mg, q.d.) alone was compared with IFN and LAM combination (2 months of LAM to be followed by combination treatment). IFN monotherapy was given only to treatment‐naïve patients. In both treatment‐naïve and previous IFN users, end of treatment virological and biochemical responses were similar with IFN–LAM combination and superior to LAM monotherapy (P < 0.05). Improvement in liver histology occurred more often with IFN ± LAM than with LAM alone (P < 0.05). In treatment‐naïve patients, combination treatment was not superior to IFN monotherapy. After treatment discontinuation, virological and biochemical response rates decreased in LAM and IFN combination and IFN monotherapy. On treatment virological response at month 6 of treatment predicted sustained virological response. The results of this study suggest that addition of LAM to IFN for the treatment of delta hepatitis is of no additional value and that both treatment modalities are superior to LAM monotherapy.
Digestive Diseases and Sciences | 2001
Ozden Uzunalimoglu; Cihan Yurdaydin; Hülya Çetinkaya; Hakan Bozkaya; Tülin Sahin; S. Colakoglu; Ethem Tankurt; Mustafa Sarioglu; Seren Ozenirler; Hikmet Akkiz; Nurdan Tozun; Halil Degertekin; Atilla Ökten
The contribution of hepatitis B, hepatitis C, and excess alcohol intake to the development of hepatocellular carcinoma in Turkey was assessed. The study was conducted through a questionnaire sent to seven major medical referral centers in different regions of Turkey and is based on 207 patients seen in the period 1994–1997. Of the seven centers, two were located in West Turkey (54 patients), two were in Central Turkey (85 patients), and two were in south and southeast Turkey (68 patients). In 196 of the 207 patients (94.7%), there was a history of chronic liver disease, and in 180 patients (87%) liver cirrhosis was documented. Of the 207 patients, 116 (56%) had hepatitis B, 48 (23.2%) had hepatitis C, and 33 (15.9%) had a history of excess alcohol intake. Anti-delta testing was available in 69 of 116 patients with hepatitis B, and anti-HDV was positive in 13 of these patients (13/69, 18.8%). Of the 33 patients with a history of heavy alcohol intake, 18 had concomitant chronic viral hepatitis infection, and alcohol alone was the etiology of hepatocellular carcinoma in only 15 cases (7.2%). The distribution of etiologic factors was not homogenous in different geographical regions in Turkey. In central, south, and southeastern Turkey, the predominant etiology of hepatocellular carcinoma was hepatitis B, whereas in western Turkey the impact of hepatitis B, hepatitis C, and alcohol was similar. This study indicates that hepatitis B virus infection is the leading cause of hepatocellular carcinoma in Turkey, followed by hepatitis C infection and alcoholic liver disease.
Journal of Gastroenterology | 2006
Senem Ceren Özen; Ülkü Daǧlı; Mesut Yalin Kiliç; Murat Törüner; Yasemin Çelik; Muhip Özkan; Irfan Soykan; Hülya Çetinkaya; Aysel Ülker; Ali Özden; A. Mithat Bozdayi
PurposeThe genetic susceptibility of people with certain NOD2/CARD15, NOD1/CARD4, and ICAM-1 gene variants to inflammatory bowel disease is still under investigation. The aim of this study was to investigate polymorphisms in the NOD2/CARD15 (R702W, G908R, and 3020insC), NOD1/CARD4 (E266K, D372N), and ICAM-1 (G241R, K469E) genes, which are known to be associated with inflammation, in Turkish patients with inflammatory bowel disease and healthy control groups.MethodsThe genotypes of 70 patients with endoscopically and histopathologically diagnosed Crohns disease (38 men, 32 women; mean age, 38.8 ± 1.3), 120 patients with ulcerative colitis (67 men, 53 women; mean age, 41.7 ± 1.3) and 106 healthy control subjects (37 men, 69 women; mean age, 35.7 ± 1.4), who stated that they had never had any prior bowel disease history, were compared. A polymerase chain reaction-restriction fragment length polymorphism analysis was performed for two variants of the ICAM-1 gene, the three main variants of the NOD2/CARD15 gene, and the E266K variant of the NOD1/CARD4 gene, and DNA sequencing was used for the D372N polymorphism of the NOD1/CARD4 gene.ResultsIn this study, the three previously described Crohns disease-predisposing variants of the NOD2/CARD15 gene and the polymorphisms examined in the NOD1/CARD4 and ICAM-1 genes were not found to be associated with ulcerative colitis or Crohns disease.ConclusionsThese findings suggest that the polymorphisms observed in the NOD2/CARD15, NOD1/CARD4, and ICAM-1 genes are not genetic susceptibility factors for Crohns disease or ulcerative colitis in Turkey.
Journal of Clinical Virology | 2001
A. Mithat Bozdayi; Hakan Bozkaya; Ahmet R Turkyilmaz; Mustafa Sarýodlu; Hülya Çetinkaya; Selim Karayalcin; Cihan Yurdaydin; Ozden Uzunalimoglu
BACKGROUND Mutation in the hepatitis B virus precore codon 28, creating a translational stop codon and double 1762-1764 T/A mutations in the core promoter region, controlling the transcription of the precore RNA and the core RNA have been suggested to correlate with the HBeAg status of patients with HBV infection. OBJECTIVES The aim of the study was to further investigate the association of nucleotide divergences in both core promoter and precore regions with liver cell injury (reflected by ALT levels) in patients with chronic HBV infection. STUDY DESIGN The sequences of the core promoter and the precore region of HBV isolated from 67 patients, all having genotype D and subtype ayw were analyzed. The patients were divided into two groups and four subgroups according to their HBeAg and Anti-HBe status, and ALT profile. RESULTS It was found that the nucleotide divergences in the core promoter but not in the precore region were higher in patients having persistently elevated serum ALT than in serum ALT normal patients in both HBeAg positive and Anti-HBe positive groups (P<0.05). The number of T/A and A1896 stop codon mutations did not yield a statistically significant difference between ALT normal and elevated groups. It was also found that 1762-1764 T/A and precore A 1896 mutation existed in five and six out of 29 HBeAg positive patients, respectively. In 38 anti-HBe positive patients, 1762-1764 T/A and precore A1896 mutation were detected in three and 16 patients respectively, and coexisted in 10 patients. CONCLUSIONS Precore A 1896 stop codon mutation seems to play an essential role in the loss of HBeAg in Turkish patients. Serum viremia levels of HBV in patients having precore stop codon and/or T/A mutation were not significantly different from the other patients carrying wild type strains. Nucleotide variability in the core promoter region may be one of the factors linked to hepatitis B disease activity.
Journal of Viral Hepatitis | 2005
Cihan Yurdaydin; Hakan Bozkaya; Hülya Çetinkaya; Sahin T; Karaoğuz D; Murat Törüner; Erkan O; Heper Ao; Esra Erden; A.M. Bozdayi; Ozden Uzunalimoglu
Summary. To determine whether combination treatment of HBeAg(−) chronic hepatitis B is beneficial we studied 78 patients with HBeAg(−), HBV DNA‐positive chronic hepatitis B who were randomized to lamivudine, 100 mg, qd, for 12 months or lamivudine–interferon (9 MU, t.i.w.) in combination. In the combination arm, 2 months of lamivudine treatment preceded 10 months of combination treatment. Biochemical, virologic and histologic responses were assessed at the end of treatment, after six and a median 27 months of drug‐free follow‐up (short‐ and long‐term follow‐up, respectively). Virologic response was defined as undetectable HBV DNA with a hybridization assay and biochemical response as normal alanine aminotransferase (ALT). Change in HBV DNA was also assessed by real‐time polymerase chain reaction (PCR). Presence of YMDD mutants at the end of treatment was investigated with a line probe assay. Both treatment regimes led to a median 2 log decline in HBV DNA levels. Virologic end of treatment responses were 90 and 92% with mono‐ and combination treatment, respectively. Corresponding virologic responses at short‐ and long‐term follow‐up were 59 and 54%, and 27 and 25%, respectively. Patients having a baseline HBV DNA value ≥200 pg/mL were more likely to relapse within 6 months off therapy than those patients with a baseline HBV DNA level <200 pg/mL (P = 0.041). YMDD mutants were observed in 53% of patients receiving lamivudine compared with 24% of patients receiving the combination regime (P = 0.017). In conclusion, efficay of combination treatment is similar to lamivudine monotherapy. However, combination treatment decreases the development of YMDD mutant strains compared with lamivudine monotherapy.
Scandinavian Journal of Gastroenterology | 2006
Yasemin Çelik; Ulku Dagli; Mesut Yalin Kiliç; Murat Törüner; Senem Ceren Özen; Muhip Özkan; Irfan Soykan; Hülya Çetinkaya; Aysel Ülker; Ali Özden; A. Mithat Bozdayi
Objective. Crohns disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the bowel, the causes of which are not fully known. Ethnic differences in disease prevalence, familial aggregation of the disease and studies of twins provide the most important evidence to suggest that genetic factors play a role in the pathogenesis of inflammatory bowel disease (IBD). The aim of this study was to examine the allelic polymorphisms that can determine the immune response levels in tumor necrosis factor alpha (TNFα), interleukin-1β (IL-1B), interleukin-1 receptor antagonist ( IL-1RN) and interleukin-10 (IL-10) genes and to investigate their roles in the inflammatory pathway in IBD. Material and methods. The study included 120 patients with UC and 70 patients with CD who were diagnosed either endoscopically or histopathologically. The control group comprised 105 healthy individuals who stated that they had never had any bowel disease during their life span. The polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method for polymorphisms in the TNFα gene at positions −308 and −238, the IL-10 gene at positions −1082 and −627, the IL-1B gene at −511 regions and the variable number of tandem repeat (VNTR) method for polymorphism in the intron 2 of the IL-1RN gene were performed. The results were analyzed on agarose gel electrophoresis. Results. No significant differences were found in the allele and genotype frequencies of the polymorphisms in the IL-1B, IL10, TNFα and IL-1RN genes between the patients with UC and CD and controls. Conclusions. The results suggest that these polymorphisms were not important risk factors in the susceptibility to IBD in Turkish patients.
Clinics | 2009
Mustafa Erbayrak; Cansel Türkay; Elife Eraslan; Hülya Çetinkaya; Benan Kasapoglu; Mehmet Bektas
INTRODUCTION: Invasive and non-invasive tests can be used to evaluate the activity of inflammatory bowel diseases. OBJECTIVE: The aim of the present study was to investigate the role of fecal calprotectin in evaluating inflammatory bowel disease activity and the correlation of fecal calprotectin with the erythrocyte sedimentation rate and C reactive protein values in inflammatory bowel disease. METHOD: Sixty-five patients affected with inflammatory bowel disease were enrolled. Twenty outpatients diagnosed with inflammatory bowel disease comprised the control group. RESULTS: In the present study, all patients in the control group had an fecal calprotectin value lower than the cut-off point (50 mg/kg). CONCLUSION: In conclusion, fecal calprotectin was found to be strongly associated with colorectal inflammation indicating organic disease. Fecal calprotectin is a simple and non-invasive method for assessing excretion of macrophages into the gut lumen. Fecal calprotectin values can be used to evaluate the response to treatment, to screen asymptomatic patients, and to predict inflammatory bowel disease relapses.
European Journal of Internal Medicine | 2010
Esin Korkut; Mehmet Bektas; Erkin Oztas; Mevlut Kurt; Hülya Çetinkaya; Ali Özden
BACKGROUND AND AIMS Celiac disease shares several symptoms which constitute some of the ROME criteria used for the diagnosis of irritable bowel syndrome (IBS), and as such many patients with underlying Celiac disease may be mistakenly diagnosed as having IBS. The aim of the present study was to determine the prevalence of Celiac disease in patients with IBS fulfilling ROME III criteria. MATERIALS AND METHODS Patients who fulfilled ROME III criteria for irritable bowel syndrome were screened for Celiac disease using the Biocard(TM) Celiac Disease Stick test, and patients who tested positive had their serum samples analyzed for antigliadin IgA and IgG, and anti-tissue transglutaminase IgA antibodies. Patients with detectable antibody levels underwent endoscopic duodenal biopsy to confirm a diagnosis of Celiac disease. RESULTS Two of 100 patients who were diagnosed as having irritable bowel syndrome as per the Roma III criteria were found to have elevated levels of serum antigliadin IgA and IgG, and anti-tissue transglutaminase IgA antibodies, with histological evidence of Celiac disease on examination of duodenal biopsy. Both patients were started on a gluten-free diet, showing significant improvement in their symptoms on follow-up. CONCLUSIONS Celiac disease is a common finding among patients labeled as IBS. Celiac disease must be considered in differential diagnosis of IBS especially in the therapy refractory group.
Journal of Clinical Gastroenterology | 2010
Ramazan Idilman; Mehmet Bektas; Kubilay Cnar; Murat Törüner; Ethem Turgay Cerit; Beyza Doganay; Esra Erden; Hakan Bozkaya; Kadir Bahar; Selim Karayalcin; Irfan Soykan; Murat Palabiyikoglu; Hülya Çetinkaya; Cihan Yurdaydin; Abdülkadir Dökmeci; Ali Özden
Background and Goals The aim of this cohort study was to determine the characteristics and clinical outcome of 170 patients with drug-induced liver injury (DILI) in a single center. Study Between January 2001 and June 2007, a total of 170 individuals who were diagnosed with DILI were retrospectively analyzed. The median follow-up period was 110.0 days. Results During the study period, a total of 5471 new patients were assessed for liver test abnormalities. Of those, 170 patients (3.1%) fulfilled the criteria of DILI. A total of 83 different drugs were considered to be related to the hepatotoxicity; a single drug was suspected in 57.6% of individuals. The median interval between the suspicious drug intake and DILI recognition was 15.0 days. Hepatocellular pattern was observed in 50.0% of patients with a mean alanine aminotransferase level of 952.2±907.0 U/L. The main causative group of drugs was antibiotics. Sixty-two patients required hospitalization; acute liver failure developed in 14 (8.2%), chronicity was observed in 19 (11.2%), and 7 died (4.1%). Overall, complete recovery occurred in 82% of patients. The presence of jaundice on admission and shorter interval period between drug intake and DILI recognition were identified as risk factors for the development of acute liver failure. Conclusions DILI is an important cause of liver test abnormalities in outpatient clinics, and antibiotics represent the most common drug group. Overall, complete recovery after the withdrawal of the suspicious drug occurred in the majority of patients, but DILI may progress to acute liver failure, chronicity, and death.
Infection | 2000
Hakan Bozkaya; A.M. Bozdayi; N. Aslan; C. Türkay; Mustafa Sarioglu; Hülya Çetinkaya; Meral Akdogan; Kubilay Çinar; Esra Erden; K. Köse; H. Sentürk; Hikmet Akkiz; Selim Karayalcin; Cihan Yurdaydin; Ozden Uzunalimoglu
SummaryBackground: The importance of circulating immunoregulatory cytokines in response to IFN treatment and the change of in vivo production of these cytokines during interferion (IFN) treatment are not well known. We aimed to determine whether pretreatment serum levels of IL-2 and IL-10 are predictive of the response to IFN treatment and to investigate if treatment response or nonresponse has any effect on the circulating levels of these cytokines. Patients and Methods: 37 patients (18 responders and 19 non-responders) with chronic hepatitis C virus (HCV) infection who received IFN-α2b for 6 months were studied. Responders were defined by complete alanine aminotransferase (ALT) normalization and loss of HCV RNA as detected by bDNA assay while patients who had elevated ALT levels and positive HCV RNA after 6 months were considered as nonresponders. Results: Genotype distribution, ALT and HCG RNA levels were similar in responders and nonresponders. A significant number of patients with chronic hepatitis C (20/37 = 54%) had elevated IL-2 levels while IL-10 levels were not different from controls. No difference in baseline cytokine levels was observed between responders and non-responders. In the posttreatment serum samples some patients lost their detectable IL-2 or IL-10; some patients developed detectable cytokine levels after treatment irrespective of the treatment response. Conclusion: These results suggest that active liver injury in chronic hepatitis C is associated with increased circulating Th1 cytokine IL-2 but not with Th2 cytokine IL-10 and that circulating levels of these cytokines do not predict the response to IFN treatment. There is no constant and regular change in circulating levels of these cytokines under IFN treatment with respect to treatment response.