Fatih Besisik | Istanbul University (original) (raw)

Papers by Fatih Besisik

Antimicrobial Agents and Chemotherapy, 2013

ABSTRACTWe evaluated the efficacy of tenofovir disoproxil fumarate (TDF) in patients with lamivud... more ABSTRACTWe evaluated the efficacy of tenofovir disoproxil fumarate (TDF) in patients with lamivudine failure (LAM-F) in comparison with that in nucleoside/nucleotide analogue (NA)-naïve patients with chronic hepatitis B (CHB). The criteria for inclusion were being NA naïve or having previous LAM-F and receiving TDF therapy for at least 6 months. Biochemical and virological tests were performed at the baseline, at 3-month intervals in the first year, and every 6 months thereafter. The primary outcome measure for efficacy was a complete virological response (CVR), defined as an HBV DNA level of <20 IU/ml. CVR rates were calculated by Kaplan-Meier analysis, and a multivariate Cox proportional-hazard model was generated in order to find predictive factors independently associated with the time to a CVR. We included 197 patients in the study (136 males; mean age, 43 ± 12 years; 105 patients were NA naïve). Sixty-five patients had hepatitis B e antigen (HBeAg)-positive CHB. The median ...

Journal of Clinical Gastroenterology, 2013

Background: Association of NOD2 (CARD15) gene mutations with inflammatory bowel diseases (IBD) is... more Background: Association of NOD2 (CARD15) gene mutations with inflammatory bowel diseases (IBD) is well known. We herein aimed to investigate the role of familial Mediterranean fever-associated MEFV variations in IBD patients as additional regional-specific risk factor. Study: One hundred thirty-seven (78 female, 56.9%) IBD patients [62 Crohn's disease (CD), 75 ulcerative colitis (UC)] were enrolled into the study. The diagnosis of all patients was confirmed by colonoscopy, histopathology, and the clinical findings. One hundred one healthy donors' samples were used as healthy controls. All patients were genotyped for the most common E148Q, M608I, M694V, and V726A variations of the MEFV and R702W, G908R, and 1007fs of the NOD2.

American Journal of Hematology, 1999

ABSTRACT

Liver International, 2015

To evaluate the efficacy of tenofovir in chronic hepatitis B (CHB) patients with adefovir resista... more To evaluate the efficacy of tenofovir in chronic hepatitis B (CHB) patients with adefovir resistance (ADF-R) and suboptimal response to adefovir (ADF-S). Nucleos(t)ide analogue (NA)-naïve patients and patients with previous adefovir-failure receiving tenofovir therapy for at least 6 months were included in the study. Biochemical and virological tests were obtained at baseline and 3-month intervals in the first year and every 6 months thereafter. The primary outcome measure was complete virological response (CVR) (HBVDNA&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;20 IU/ml). CVR rates were calculated by Kaplan-Meier analysis and a multivariate Cox proportional hazard model was generated to find out factors independently associated with CVR. 165 patients (118 male, mean age 42±12, 64 HBeAg(+) ) were included in the study. There were 105 patients in NA-naïve, 32 patients in ADF-S, and 28 patients in ADF-R groups. All patients in the ADF-R group had multidrug resistance patterns. Mean duration of tenofovir treatment was 29±14 months. CVR rates in NA-naïve, ADV-S and ADV-R groups were 65% vs 75% vs 58% at 12(th) month, 77% vs 87% vs 79% at 24(th) month and 83% vs 94% vs 79% at 36(th) month, respectively. According to multivariate Cox regression model HBeAg-positivity (HR=0.56, 95%CI 0.36-0.86, p=0.008), high baseline HBVDNA level (HR=0.64, 95%CI 0.55-0.74, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001) and ADF-R (HR=0.47, 95%CI 0.28-0.81, p=0.006) were independent predictors for CVR. Seven patients encountered mild renal dysfunction and managed by dose adjustments. CVR rates during the follow-up shows that tenofovir has a decreased, yet still potent in vivo efficacy against multidrug resistant strains of HBV. This article is protected by copyright. All rights reserved.

No abstract is available. To read the body of this article, please view the PDF online. ... © 200... more No abstract is available. To read the body of this article, please view the PDF online. ... © 2008 AGA Institute. Published by Elsevier Inc. All rights reserved. ... Advertisements on this site do not constitute a guarantee or endorsement by the journal, Association, or publisher of the ...

Background Levels of prohepcidin, a homeostatic regulator of iron absorption, are altered in chro... more Background Levels of prohepcidin, a homeostatic regulator of iron absorption, are altered in chronic hepatitis C and liver cirrhosis. However, data on the potential alterations of prohepcidin in patients with HBV-related liver disease are scarce. We investigated whether serum prohepcidin is related to iron overload and perenchymal dysfuction in HBV-related liver disease. Methods Three groups of subjects were studied: 66 patients with chronic hepatitis B, 32 patients with HBVrelated cirrhosis, and 42 healthy controls without evidence of liver disease. Serum levels of prohepcidin were determined by enzyme-linked immunosorbent assay. Results Serum prohepcidin levels were significantly lower in patients with HBV-related cirrhosis (175.85 ± 71.5 ng/ml) than in patients with chronic hepatitis B (209.02 ± 62.7 ng/ml P \ 0.05) and controls (222.4 ± 128.4 ng/ml, P \ 0.05). After adjustment for potential confounders, prohepcidin was found to be an independent predictor of ferritin levels in multiple linear regression analysis (b = -1.10, t = -3.11, P \ 0.01).

Chronic hepatitis C infection is a common problem in renal allograft recipients, this study was d... more Chronic hepatitis C infection is a common problem in renal allograft recipients, this study was designed to investigate the association of serum aminotransferase levels with liver histology, in renal transplant patients with chronic hepatitis C virus (HCV) infection, in the long term. In this study, 82 HCV-infected renal allograft recipients, who were followed up with functioning grafts for at least 6 months, were analyzed. Patients were classified according to their transaminase values as persistently normal, intermittently abnormal, or continuously abnormal liver function tests. Serum transaminase levels exceeding at least 1.5 times the upper limit of normal (40 IU) for periods longer than 1 month were taken as abnormal. Patients with abnormal liver function tests owing to HCV unrelated causes (drugs, alcohol, or other toxic substances, other viruses, etc.) were excluded from the study. Forty-eight of these patients underwent at least one liver biopsy. Of the 82 patients, 34 (41.5%) had persistently normal (liver biopsy revealed normal or minimal changes in 77.0%, chronic persistent hepatitis in 15.3%, chronic active hepatitis in 7.7%; no patient had cirrhosis), 29 (35.3%) intermittently abnormal (liver histology was consistent with minimal changes in 50%, chronic persistent hepatitis in 27.8%, chronic active hepatitis in 16.7%, cirrhosis in 5.5%), 19 (23.2%) persistently abnormal (liver biopsy showed minimal changes in 41.1%, chronic persistent hepatitis in 17.6%, chronic active hepatitis in 35.3%, cirrhosis in 5.9%) transaminase values. Although continuously or intermittently elevated transaminases do not always indicate morphologically advanced disease, the normal course of serum transaminases is mostly accompanied by normal, or near-normal, liver histology, in HCV-infected renal transplant patients. Liver biopsy is not indicated in deciding disease severity in these patients unless clinical findings dictate otherwise.

Clinical Transplantation, 1999

In this cross-sectional, controlled study, Helicobacter pylori (H. pylori ) infection, a probable... more In this cross-sectional, controlled study, Helicobacter pylori (H. pylori ) infection, a probable factor in the development of gastrointestinal problems, was investigated in dialysis patients and renal transplant recipients. Forty-seven dialysis patients (22 male, 25 female, mean age of 36.6 9 15 yr (range 18 -83 yr)), 57 renal transplant recipients (39 male, 18 female, mean age of 36.8 9 10 yr (range 19-60 yr)) and 55 healthy individuals (34 male, 21 female, mean age of 33.4 9 9.6 yr (range 21 -58 yr)) were included and no significant difference was found in the study groups. The mean time spent on dialysis in the hemodialysis group was 32.5 927.7 months (range 1-100 months). H. pylori antibodies were detected in 22 of 57 (38.6%) patients in the transplantation group, 31 of 47 (65.9%) patients in the dialysis group and 39 of 55 (72.5%) in the control group. No correlation was found between H. pylori infection and age, sex, primary disease, frequency of dialysis, duration and type of transplantation and the immunosuppressive therapy. However, patients with H. pylori antibodies spent a shorter time on dialysis compared to patients without the antibodies (26.6 9 23.5 vs 44.1 9 32.1 months, p = 0.038). The frequency of H. pylori infection in the transplantation group was significantly lower than the control and dialysis groups (p B 0.01). This finding may be explained on the basis of decreased humoral antibody response to H. pylori infection, secondary to immunosuppressive therapy rather than decreased incidence of infection in the transplantation group. Finally, we concluded that the value of the serological test for diagnosis of H. pylori infection should be interpreted cautiously in these patient groups.

Transplantation Proceedings, 2005

Veno-occlusive disease (VOD) of the liver occurs in 10% to 50% of patients after hematopoietic st... more Veno-occlusive disease (VOD) of the liver occurs in 10% to 50% of patients after hematopoietic stem cell transplantation (HSCT), ranging from a mild reversible disease to a fulminant course with a mortality rate close to 100%. We retrospectively evaluated the clinical signs, diagnosis, prognosis, therapy, and outcome of 13 hepatic VOD cases which developed after HSCT. A total of 193

Scandinavian Journal of Gastroenterology, 2006

Hepatic hydrothorax is a complication of cirrhosis that is uncommon and difficult to treat. Diure... more Hepatic hydrothorax is a complication of cirrhosis that is uncommon and difficult to treat. Diuretic therapy, thoracentesis, transjugular intrahepatic portosystemic shunt and liver transplantation are the main therapeutic options. Here, we report on a 47-year-old man with decompensated liver cirrhosis related to hepatitis B and D virus infections and who had complications of hepatic hydrothorax and hepatorenal syndrome. In this case, the hepatic hydrothorax, which was refractory to thoracic tube drainage and octreotide treatment, could be controlled with 5 days of terlipressin therapy associated with albumin. Terlipressin administration resulted in both improvement in renal function and successful resolution of hepatic hydrothorax. Splanchnic vasoconstrictor agents that reduce splanchnic blood flow, increase both central volume and effective renal blood flow. Thus they improve renal function. In our case, terlipressin, known to be beneficial in hepatorenal syndrome, was also effective in the treatment of hepatic hydrothorax probably by similar mechanisms. This is the first case in the literature.

Gastroenterology, 2003

... Volume 124, Issue 4, Pages A762, April 2003, Authors:Ahmet Danalioglu; Sabahattin Kaymakoglu;... more ... Volume 124, Issue 4, Pages A762, April 2003, Authors:Ahmet Danalioglu; Sabahattin Kaymakoglu; Yilmaz Cakaloglu; Kadir Demir; Filiz Akyuz; Nevzat Aksoy; Sule Poturoglu; Salih Turkoglu; Selim Badur; Fatih Besisik; Atilla Okten; Ahmet Danalioglu; Sabahattin Kaymakoglu ...

Scandinavian Journal of Gastroenterology, 2010

Objective. Recently, mucosal changes of small bowel were defined by developing new imaging techni... more Objective. Recently, mucosal changes of small bowel were defined by developing new imaging techniques including capsule endoscopy (CE) in portal hypertensive patients. However, the clinical impact of these changes is unknown. In this study, we aimed to determine the additional cause of blood loss in portal hypertensive patients. Material and methods. A total of 444 portal hypertensive patients, hospitalized in our clinic between 2005 and 2007, were evaluated. Patients with obscure bleeding were enrolled to this prospective case-control study. CE was performed in 21 patients who met inclusion criteria. Gastroscopy, colonoscopy and computerized tomography/small bowel enema were performed in all patients. Results. Fourteen cirrhotic and seven noncirrhotic portal hypertensive patients were enrolled to this study. Mean age of patients was 47.9 ± 15.6 years, and 13 of 21 were male. Small bowel varices were found in 7 patients (1 active bleeding) and other mucosal abnormalities in 10 patients (vascular ectasia, erosion and edema, 1 active bleeding). Although two of them were normal, jejunal malignant mass was found in two patients (1 active bleeding). Of 21 patients, 19 (90.5%) patients had portal hypertensive abnormalities (including varices). However, ileal varices rate was 57.1% (4 patients) in noncirrhotic portal hypertensive patients and 21.4% (3 patients) in cirrhotics. Conclusion. Ninety percent of patients had portal hypertensive abnormalities in small bowel and one-third of them had small bowel varices. Small bowel varices and vascular ectasia were the main causes of obscure bleeding in portal hypertensive patients.

Pharmacy World & Science, 2006

Helicobacter pylori is the most important etiologic agent for development of peptic ulcer, chroni... more Helicobacter pylori is the most important etiologic agent for development of peptic ulcer, chronic gastritis and gastric carcinomas. It is now well established that H. pylori eradication treatment is more cost-effective than acid suppressing therapies alone for the treatment of peptic ulcer disease. However, the comparative cost-effectiveness of various H. pylori eradication regimens is still not clear. This study was designed to make a pharmacoeconomic comparison of different H. pylori eradication regimens in patients with peptic ulcer disease or chronic gastritis, using real-world cost and effectiveness data. Istanbul University Hospital and Marmara University Hospital. A total of 75 patients diagnosed as H. pylori (+) by endoscopy were randomized to receive one of the seven H. pylori treatment protocols. These protocols were as follows: (LAC) = &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;lansoprazole 30 mg bid + amoxicillin 1 g bid + clarithromycin 500 mg bid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; for 7 days and (OCM) = &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;omeprazole 20 mg bid + clarithromycin 250 mg bid + metronidazole 500 mg bid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;; (OAM) = &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;omeprazole 40 mg qd + amoxicillin 500 mg tid + metronidazole 500 mg tid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;; (MARB) = &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;metronidazole 250 mg tid + amoxicillin 500 mg qid + ranitidine 300 mg hs + bismuth 300 mg qid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;; (OAC) = omeprazole 20 mg bid + amoxicillin 1 g bid + clarithromycin 500 mg bid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;; (OCA) = omeprazole 40 mg bid + clarithromycin 500 mg bid + amoxicillin 1 g bid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;; (OAB) = &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;omeprazole 20 mg bid + amoxicillin 500 mg tid + bismuth 300 mg qid&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; each for 14 days. Only direct costs were included in the analysis. Effectiveness was measured in terms of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;successful eradication&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;. The cost-effectiveness ratios of the regimens were calculated using these effectiveness and cost data. The perspective of the study was assumed as the Government&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s perspective. Cost-effectiveness ratios of eradication regimens. MARB and OCA regimens were found to be more cost-effective than the other treatment regimens. The eradication rates and cost-effectiveness ratios calculated for these protocols were 90% (158.7 euros) for MARB and 90% (195.8 euros) for OCA regimen. This study confirms the importance of using local pharmacoeconomic data. Analyses such as this give decision-makers the tools to choose a better treatment option which is both highly effective yet and has a low cost.

Liver International, 2009

Background: There is little information about the prevalence of occult hepatitis B virus infectio... more Background: There is little information about the prevalence of occult hepatitis B virus infection (OHBVI). We have investigated the prevalence and virological features of OHBVI among female sex workers (FSWs) in Istanbul. Methods: Hepatitis B surface antigen (HBsAg) was tested in FSWs who work uncontrolled and were admitted to Venereal Diseases Hospital. HBV DNA and anti-HBs were investigated in all the HBsAg-negative cases. Hepatitis B envelope (HBe) antigen, anti-HBe, anti-hepatitis B core (HBc) antigen, HBV genotype, S gene and precore (PC)/basic core promoter (BCP) mutations were determined in HBV DNA-positive sera. Results: Two hundred and eighty-six volunteers were enrolled and 32.5% (n = 93) of them had anti-HBs positivity. HBV DNA (range 30-209 copy/ml) was positive in 11 anti-HBs-negative and two anti-HBs-positive cases. The prevalence of OHBVI was 4.5% (13/286). Anti-HBc was positive in 77% (10/13) of those with OHBVI and anti-HBe positivity was 53.8% (7/13). Only genotype D was present in all occult HBV-infected cases. One PC (G1896A) and one BCP (T1762/A1764) mutation was found, but S gene mutation was not detected in any of the samples. Conclusion: In this population, OHBVI may have a negligible role in the horizontal transmission because of a very low viral load, and PC and core promoter mutations are very rare.

Journal of Hepatology, 2009

Poster Session − Saturday, April 25 peginterferon alfa-2a (extension group) or no further treatme... more Poster Session − Saturday, April 25 peginterferon alfa-2a (extension group) or no further treatment (follow-up group). HBsAg and HBeAg levels were determined every 12 weeks. Results: HBeAg was cleared in 37.5% (6/16) of patients in the extension group, five of them with HBeAg seroconversion, compared with no patients in the follow-up group (P = 0.043). HBV DNA became undetectable (<10 3 copies/mL) in 81% (13/16) of the extension group and 53% (8/15) of the follow-up group (P = 0.135). 18.8% (3/16) of patients in the extension group achieved HBsAg clearance compared with no patients in the follow-up group (P = 0.227). HBV DNA relapse occurred in 12.5% (2/16) and 40% (6/15) of the extension and follow-up groups, respectively (P = 0.113). Reductions in HBsAg and HBeAg levels were significantly greater in the extension group than in the follow-up group (P < 0.05).

Journal of Hepatology, 2008

The study included 1138 patients from 16 centers and 9 states in Brazil. The mean age was 49.46±1... more The study included 1138 patients from 16 centers and 9 states in Brazil. The mean age was 49.46±12.75 years; 53% were males and 85% were asymptomatic. Hyperlipidemia was observed in 66.3% cases, obesity (BMI 30 kg/m 2 ) in 37.3%, overweight (BMI < 30 kg/m 2 >25 kg/m 2 ) in 35.8%, diabetes in 23.3%, toxins exposure in 10.9%. Metabolic Syndrome (ATP III) was observed in 41.3% cases. Elevated levels of ALT, AST and GGT were observed in 55.8%, 42.2% and 63.1% cases, respectively. Liver biopsy was performed in 371 cases. Isolate steatosis was observed in 25.3% cases, steatohepatitis in 74.7%. Stages of fibrosis: S zero: 28.8%, S1: 36.1%, S2 in 11.9%, S3 in 7.8%, cirrhosis in 15.4%.

Journal of Hepatology, 2003