Kadir Bahar
Ankara University
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Featured researches published by Kadir Bahar.
Radiology | 2013
Ilkay S. Idilman; Hatice Aniktar; Ramazan Idilman; Gökhan Kabaçam; Berna Savas; Atilla Halil Elhan; Azim Celik; Kadir Bahar; Musturay Karcaaltincaba
PURPOSE To determine utility of proton density fat fraction (PDFF) measurements for quantifying the liver fat content in patients with nonalcoholic fatty liver disease (NAFLD), and compare these results with liver biopsy findings. MATERIALS AND METHODS This retrospective study was approved by the institutional review board with waivers of informed consent. Between June 2010 and April 2011, 86 patients received a diagnosis of NAFLD. Ten patients did not accept liver biopsy and six patients had contraindications for magnetic resonance (MR) imaging. Seventy patients were included in this study. Seventy patients with NAFLD (40 men, 30 women; mean age, 44.7 years; range, 16-69 years) underwent T1-independent volumetric multiecho gradient-echo imaging with T2* correction and spectral fat modeling. Median time interval between MR imaging and liver biopsy was 14.5 days (range, 0-259 days). MR examinations were performed with a 1.5-T MR imaging system. Complex-based PDFF measurements were performed by placing regions of interest in Couinaud system segments V-VI and all liver segments from I to VIII. All liver biopsy specimens were retrieved from archives and evaluated by one pathologist for hepatic steatosis according to criteria from a previous study. Pearson correlation coefficient, receiver operating characteristics, and linear regression analyses were used for statistical analyses. RESULTS Mean PDFF calculated with MR imaging was 18.1% ± 9.5 (standard deviation). Close correlation for quantification of hepatic steatosis was observed between PDFF and liver biopsy (r = 0.82). PDFF was effective in discriminating moderate or severe hepatic steatosis from mild or no hepatic steatosis, with area under the curve of 0.95. The correlation between biopsy and PDFF-determined steatosis was less pronounced when fibrosis was present (r = 0.60) than when fibrosis was absent (r = 0.86; P = .02). CONCLUSION PDFF measurement by MR imaging provided a noninvasive, accurate estimation of the presence and grading of hepatic steatosis in patients with NAFLD. Hepatic fibrosis reduced the correlation between biopsy results and PDFF.
European Journal of Gastroenterology & Hepatology | 2005
Ozlem Erkan; A.M. Bozdayi; Selcuk Disibeyaz; Dilek Oguz; Muhit Ozcan; Kadir Bahar; Selim Karayalcin; Ali Özden; Hakan Bozkaya; Cihan Yurdaydin; Ozden Uzunalimoglu
Objective Thrombophilic gene mutations have been reported to be associated with the formation of portal vein thrombosis (PVT). This study aimed to investigate the role of thrombophilic gene mutations in cirrhotic patients with PVT. Patients and methods A total of 74 cirrhotic patients (17 with PVT, 57 without PVT), and 19 non-cirrhotic patients with PVT and 80 healthy controls were included. Factor V Leiden G1691A, prothrombin G20210A and methylenetetrahydrofolate reductase C677T mutations were analysed by restriction fragment length polymorphism. Results Aetiologies and Child–Pugh distribution of cirrhotic patients with and without PVT were similar. Five of 17 (29%) of cirrhotic patients with PVT but only two of 57 (3.5%) of cirrhotics without PVT, five of 80 (6%) of controls and none of the 19 non-cirrhotic patients with PVT had factor V Leiden G1691A mutation (P<0.05). Prothrombin G20210A mutation was found in five (29%) cirrhotic patients with PVT while only two (3.5%) cirrhotic patients without PVT, one (5%) non-cirrhotic patient with PVT and two (2.5%) controls had this mutation (P<0.05). The frequency of the homozygote methylenetetrahydrofolate reductase 677C-T mutation was similar in all four groups. Conclusions Inherited thrombophilic gene mutations appear to increase the risk of PVT formation in cirrhotic patients but not in patients without liver disease in a cohort of Turkish patients.
Acta Cytologica | 2003
Isin Soyuer; Cemil Ekinci; Muhsin Kaya; Yasemin Genç; Kadir Bahar
OBJECTIVE To evaluate the importance of fine needle aspiration cytology (FNAC) in the diagnosis of hepatocellular carcinoma (HCC). STUDY DESIGN We analyzed 17 cytologic and 5 architectural features in a series of 320 FNACs from HCC and compared them with 73 FNACs from benign lesions and with 705 FNACs from metastatic carcinomas. One thousand ninety-eight patients who were diagnosed by liver FNAC between December 1988 and July 1998 and had adequate follow-up were included in the study. The specimens were evaluated according to the presence or absence of the cytologic features and cellular arrangement. A stepwise logistic regression analysis was performed on the data to determine the variables predictive of HCC. RESULTS Multinucleated tumor giant cells, cytoplasmic hyaline and central sinusoidal pattern were selected as the 3 most predictive parameters for differentiated reactive hepatocytes from HCC (P < .0001), while bile, centrally located nucleus in an atypical cell and intranuclear inclusion were selected as the 3 most predictive parameters for differentiated metastatic carcinoma from HCC (P < .0001-< .001) by stepwise logistic regression analysis. CONCLUSION In the 1,098 patients suspected of having hepatic malignancy, a correct diagnosis was made by a combination of the above features. The sensitivity of this procedure for hepatic malignancy was 99.5%, and the specificity was 100%.
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.
Journal of Viral Hepatitis | 2012
Ramazan Idilman; Kubilay Çinar; Gülseren Seven; Y. Bozkus; Atilla Halil Elhan; Mithat Bozdayi; Cihan Yurdaydin; Kadir Bahar
Summary. The aims of this study were to assess hepatitis B surface antigen (HBsAg) seroconversion and to determine its impact on the natural course of the disease in patients with HBeAg‐negative chronic hepatitis B (CHB) during lamivudine (LMV) treatment. A total of 183 consecutive patients with HBeAg‐negative CHB who were treated with LMV were included in the study. Data were retrospectively collected from outpatient visit charts. The primary endpoint was HBsAg seroconversion to anti‐HBs. The secondary endpoint was to determine the development of cirrhosis. Loss of HBsAg was confirmed in 10 patients and seroconversion to anti‐HBs in nine patients during LMV treatment or after its discontinuation. HBsAg seroconversion was achieved on‐treatment in four patients after a median treatment duration of 30 months and off‐treatment in the remaining five patients in a median 61 months after LMV discontinuation. The cumulative probability of HBsAg seroconversion increased from 0.6% at 1 year and 1.9% at 5 years to 21.5% at 10 years of LMV during and after LMV treatment. HBsAg clearance was preceded by undetectable serum hepatitis B virus (HBV) DNA. The majority of the patients responding to treatment had undetectable HBV DNA levels at 24 weeks of treatment. The cumulative probability of LMV resistance increased from 2.2% at 1 year to 37.3% at 5 years. No baseline parameter predicting either HBsAg seroconversion or the emergence of LMV resistance was identified. None of the patients with HBsAg seroconversion experienced virological breakthrough or disease progression during the follow‐up period. These results indicate that HBsAg seroclearance can occur in patients with HBeAg‐negative CHB under LMV therapy and predicts better clinical outcome.
Pediatric Hematology and Oncology | 2006
Handan Ugur; Nurdan Tacyildiz; Gulsan Yavuz; Emel Unal; Ayse Sayili; Suna Emir; Aydan Kansu; Zarife Kuloğlu; Kadir Bahar
Obstructive jaundice is an unusual manifestation of non-Hodgkin lymphomas in children. Although surgical drainage is one of the initial treatment choices in some cases, usually lymphomatous masses rapidly response to chemotherapy and jaundice decreases due to regression of the mass, without any surgical procedure. The authors report the case of a 16-year-old girl who presented with biliary obstruction due to a neoplasm involving the duodenum. Histological examination of the specimen, which was taken from the mass by endoscopic biopsy, revealed Burkitt lymphoma infiltrating the duodenum. Chemotherapy including cyclophosphamide was started immediately. In a few days, jaundice decreased rapidly by the shrinkage of the mass. Neither surgery nor percutaneous drainage were needed. In conclusion, biliary tract obstruction due to non-Hodgkin lymphoma can be effectively treated with chemotherapy alone without any surgical procedure.
The Turkish journal of gastroenterology | 2014
Gülseren Seven; Kubilay Çinar; Ramazan Idilman; Acar Tuzuner; Selcuk Hazinedaroglu; Selim Karayalcin; Kadir Bahar
BACKGROUND/AIMS The aims of the present study were to review biliary complications following liver transplantation in a single-center experience, to identify the factors associated with biliary complications, and to evaluate the success of endoscopic and percutaneous treatment in such patients. MATERIALS AND METHODS Between January 1994 and June 2010, a total of 176 patients with liver disease underwent liver transplantation; 119 recipients were included in this retrospective analysis. Median posttransplant follow-up period was 49 months. RESULTS Mean age was 43.0±12.7 years. Living donor liver transplantation (LDLT) and deceased-donor liver transplantation (DDLT) were performed in 71 and 48 patients, respectively. Duct-to-duct anastomosis and Roux-en-Y hepaticojejunostomy were performed in 68 and 51 patients, respectively. The overall incidence of posttransplant biliary complications was 36%; anastomotic biliary strictures were the most common biliary complications (42%), followed by biliary leakage (28%). On logistic regression analysis, duct-duct anastomosis was the only risk factor associated with the development of biliary complications (Odds ratio (OR), 3.346; p=0.005). Endoscopic and percutaneous treatment was successful in the majority of patients (81%), and the remaining 19% recipients underwent surgery for biliary repair. Endoscopic retrograde cholangiopancreatography (ERCP) guided drainage and balloon dilatation with stent placement were the most common treatment modalities. CONCLUSION Biliary complications were most frequent after liver transplantation; biliary strictures were the most commonly seen. The use of duct-to-duct anastomosis for biliary reconstruction is a risk factor for the development of biliary complications. Endoscopic and percutaneous treatment was successful in the majority of these patients.
Journal of Clinical Gastroenterology | 2002
Irfan Soykan; Hülya Çetinkaya; Sevim Erdem; Ersin Tan; Fatih Aydin; Kadir Bahar; Ali Özden
Mitochondrial neurogastrointestinal encephalomyopathy is a rare, multisystem disorder characterized by gastrointestinal dysmotility, ptosis, neurologic findings (e.g., peripheral neuropathy), leukoencephalopathy, and thin body habitus. Gastrointestinal motility studies and skeletal muscle biopsy are recommended diagnostic tools. We report two patients that highlight the diagnostic characteristics of this rare entity.
European Journal of Internal Medicine | 2014
Mehmet Bektas; Gülseren Seven; Ramazan Idilman; Mustafa Yakut; Beyza Doganay; Gökhan Kabaçam; Yusuf Üstün; Esin Korkut; Çağdaş Kalkan; Günay Sahin; Hülya Çetinkaya; Hakan Bozkaya; Cihan Yurdaydin; Kadir Bahar; Kubilay Çinar; Irfan Soykan
INTRODUCTION/AIM Primary biliary cirrhosis is associated with other autoimmune diseases including Sjögrens syndrome, and scleroderma. Esophageal dysmotility is well known in scleroderma, and Sjögrens syndrome. The aim of this study is to investigate whether any esophageal motor dysfunction exists in patients with primary biliary cirrhosis. METHOD The study was performed in 37 patients (36 women, mean age: 56.29 ± 10.01 years) who met diagnostic criteria for primary biliary cirrhosis. Thirty-seven functional dyspepsia patients, were also included as a control group. Patients entering the study were asked to complete a symptom questionnaire. Distal esophageal contraction amplitude, and lower esophageal sphincter resting pressure were assessed. RESULTS Manometric findings in primary biliary cirrhosis patients vs. controls were as follows: Median lower esophageal sphincter resting pressure (mmHg): (24 vs 20, p=0.033); median esophageal contraction amplitude (mmHg): (71 vs 56, p=0.050); mean lower esophageal sphincter relaxation duration (sc, x ± SD): (6.10 ± 1.18 vs 8.29 ± 1.92, p<0.001); and median lower esophageal sphincter relaxation (%) (96 vs 98, p=0.019); respectively. No significant differences were evident in median peak velocity (sc) (3.20 vs 3.02, p=0.778) between patients with primary biliary cirrhosis and the functional dyspepsia patients. Esophageal dysmotility was found in 17 (45.9%) primary biliary cirrhosis patients (non-specific esophageal motor disorder in ten patients, hypomotility of esophagus in five patients, nutcracker esophagus in one patient and hypertensive lower esophageal sphincter in one patient). CONCLUSION Esophageal dysmotility was detected in 45.9% of patients. The study suggests that subclinic esophageal dysmotility is frequent in patients with primary biliary cirrhosis.
Endoskopi Gastrointestinal | 2015
Mustafa Yakut; Kubilay Çinar; Ramazan Idilman; Kadir Bahar
The pathogenesis of esophageal squamous papilloma is not fully open, but it is associated with esophagitis due to gastroesophageal reflux disease or Barretts lesions and HPV infection. Esophageal squamous cell papillomas are usually located solitary and the distal esophagus. In this case multiple squamous cell papillomas of the esophagus is reported.