Canan Alkim
Istanbul University
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Publication
Featured researches published by Canan Alkim.
Journal of Gastroenterology and Hepatology | 2004
Nihat Akbayir; Canan Alkim; Levent Erdem; H. Mehmet Sökmen; Ayşim Sungun; Tulay Basak; Suat Turgut; Zeynel Mungan
Background and Aim: Heterotopic gastric mucosal patch, which has a 0.1–10% frequency, is encountered when the cervical esophagus is examined carefully during endoscopy. In this study, we aimed to determine the prevalence of the patch in the cervical esophagus, to identify its macroscopic and histological characteristics and to evaluate demographic and clinical features.
Digestive Diseases and Sciences | 2005
Nihat Akbayir; Asli Batur ÇAliŞ; Canan Alkim; H. Mehmet Sökmen; Levent Erdem; AyÇA Özbal; F. Füsun Bölükbaş
Isolated case reports in which symptomatic hearing loss develops suddenly during the course of inflammatory bowel disease (IBD) have been reported, but the presence of subclinical sensorineural hearing loss (SNHL) associated with IBD has been investigated in only two preliminary studies.In order to research this further, we aimed to investigate the presence of subclinical SNHL in IBD by comparison with a control group and to examine possible relations between the bowel disease parameters and hearing loss.Otoscopy, tympanometry, and pure tone audiometry were carried out in 39 patients with IBD (21 Crohns disease [CD], 18 ulcerative colitis [UC]) and 25 healthy age- and sex-matched controls. All patients and control subjects had normal otoscopy findings and tympanometry was unremarkable, excluding middle ear disease and conductive hearing loss. Analysis of each frequency examined showed that the average hearing thresholds were increased significantly in the study group compared to those of the control group at higher frequencies (2, 4, and 8 kHz). When these parameters were compared with the control group according to subgroups of IBD, a significant difference was determined for the UC group at frequencies of 2, 4, and 8 kHz and for the CD group only at the frequency of 4 kHz. Although there was a trend of increment in SNHL as the age of the patient and duration and extent of UC increased, no significant correlation was observed between SNHL and these parameters or sex, activity, involvement site, medication history of IBD, and coexistence of other extraintestinal manifestations. In conclusion, it was demonstrated that a subclinical SNHL may be associated with UC and somewhat with CD, affecting mainly the high frequencies. In light of this finding, it may be advisable to investigate labyrinth functions as well as other extraintestinal manifestations in patients with IBD.
Clinical and Applied Thrombosis-Hemostasis | 2011
Huseyin Alkim; Selime Ayaz; Canan Alkim; Aysel Ülker; Burhan Sahin
This study was planned for searching possible changes of the total coagulation and fibrinolysis system in inflammatory bowel disease (IBD) in order to obtain some clues for explaining the relation between IBD and hypercoagulability. A total of 24 patients with ulcerative colitis, 12 patients with Crohn disease, and 20 healthy controls were studied. Platelets; prothrombin time (PT); partial thromboplastin time (PTT); fibrinogen; d-dimer; fibrinogen degradation products; protein C; protein S; antithrombin; thrombin time; von Willebrand factor; coagulation factors V, VII, VIII, IX, XI, and XIII; plasminogen; antiplasmin; tissue plasminogen activator; plasminogen activator inhibitor 1; and prothrombin fragments 1 + 2 were studied. Most of the procoagulants (platelets, fibrinogen, von Willebrand factor, coagulation factor IX, and plasminogen activator inhibitor 1) were found increased together with decreases in some anticoagulants (protein S and antithrombin) in IBD. Also the activation markers of coagulation (d-dimer, fibrinogen degradation products, and prothrombin fragments 1 + 2) were all increased. The parameters of the total coagulation–fibrinolysis system were increased in IBD, regardless of the form and the activity of the disease.
Scandinavian Journal of Gastroenterology | 2005
Nihat Akbayir; H. Mehmet Sökmen; Asli Batur Çaliş; Cengiz Bolukbas; Levent Erdem; Canan Alkim; Damlanur Sakiz; Zeynel Mungan
Objective. Acid secretion produced by a heterotopic gastric mucosal patch (HGMP) in the proximal esophagus, instead of gastric acid, may be responsible for laryngopharyngeal reflux (LPR), passing the upper esophageal sphincter. The aim of this study was to investigate the prevalence of HGMP in the proximal esophagus in patients with posterior laryngitis indicating the presence of LPR in comparison with a control group and to elucidate the possible role of this lesion in the pathogenesis of LPR. Material and methods. A total of 36 consecutive patients with posterior laryngitis diagnosed on laryngoscopic examination were enrolled in the study. Esophagoscopy and ambulatory 24-h intra-esophageal dual-probe pH monitoring were performed in all patients. During endoscopy, special attention was paid to the proximal part of the esophagus, and the proximal electrode for pH monitoring was placed in this region under endoscopic view. The control group comprised 660 consecutive patients who had undergone upper gastrointestinal endoscopy for the usual indications. When HGMP was found, biopsies were taken for histological confirmation. Results. HGMP was detected in 5 out of 36 patients. One out of five patients with patches was excluded from the study because the histopathology of this patients patch revealed antral-type mucosa, which is not capable of acid secretion. Thus a total of 35 patients were included in the study, yielding a HGMP prevalence of 11.4% (4/35). Compared with the prevalence of the control group (1.6%), a significant difference was observed (p<0.005). pH monitoring showed that 45.4% of the patients had abnormal proximal acid reflux. All of four HGMP (+) patients with posterior laryngitis revealed significantly higher abnormal proximal reflux compared to the patients without patches (p<0.05). Conclusions. This first preliminary study may suggest that HGMP in the cervical esophagus could play a role in the pathogenesis of LPR, at least in a minor group of patients with posterior laryngitis, depending on its capability to produce acid in situ, although isolated proximal reflux could not be demonstrated. This finding may need to be supported by further studies with larger patient populations and using acid stimulation tests.
Digestive Diseases and Sciences | 2008
Kamil Ozdil; Mehmet Sokmen; Ozdal Ersoy; Huseyin Demirsoy; Besir Kesici; Cetin Karaca; Nihat Akbayir; Levent Erdem; Canan Alkim; Damlanur Sakiz
Purpose Irritable bowel syndrome is generally diagnosed according to the symptoms of the patient, and gluten enteropathy can also be presented with similar symptoms (diarrhea and/or constipation) of irritable bowel syndrome. Aimed to assess the association and the frequency of gluten enteropathy in a group of Turkish patients diagnosed as irritable bowel syndrome. Results Found anti-gliadin IgA positivity only in four patients among patients with irritable bowel syndrome. However, none of these four patients had anti-endomycium positivity or any histopathological findings specific for gluten enteropathy. All these four patients had normal histology in their small bowel biopsies. Conclusion Irritable bowel syndrome is a common problem in the population, but gluten enteropathy is not associated with the vast majority of subjects with irritable bowel syndrome as expected. The need for screening gluten enteropathy among these patients is still unclear, and screening with serology only without small bowel biopsy may lead to false positive results.
International Journal of Inflammation | 2015
Canan Alkim; Huseyin Alkim; Ali Riza Koksal; Salih Boga; Ilker Sen
Angiogenesis is an important component of pathogenesis of inflammatory bowel disease (IBD). Chronic inflammation and angiogenesis are two closely related processes. Chronic intestinal inflammation is dependent on angiogenesis and this angiogenesis is modulated by immune system in IBD. Angiogenesis is a very complex process which includes multiple cell types, growth factors, cytokines, adhesion molecules, and signal transduction. Lymphangiogenesis is a new research area in the pathogenesis of IBD. While angiogenesis supports inflammation via leukocyte migration, carrying oxygen and nutrients, on the other hand, it has a major role in wound healing. Angiogenic molecules look like perfect targets for the treatment of IBD, but they have risk for serious side effects because of their nature.
Clinical Nephrology | 2012
Murvet Yilmaz; Abdulkadir Unsal; Mehmet Sokmen; Ozlem Harmankaya; Canan Alkim; Fevziye Kabukcuoglu; Aysim Ozagari
Amyloidosis results from extracellular deposition of a fibrillary protein in various organs, and renal biopsy is the best, but a complicated tool for diagnosis. Therefore, alternative biopsy sites have been proposed with varying degrees of sensitivity. We aimed to find the most appropriate biopsy site in patients with chronic kidney disease (CKD) in whom renal biopsy is contraindicated or unavailable. 42 patients (29 male; mean age 46 ± 16 y) with CKD in whom amyloidosis was suspected as the underlying etiology on clinical grounds, but renal biopsy was not available (Group I), and 36 patients (25 male; mean age 40 ± 16 y) with CKD in whom renal biopsy revealed AA-amyloidosis (Group II) were investigated. Upper and lower gastrointestinal tract (GIT) endoscopies were performed and multiple biopsies from gingiva, esophagus, antrum, duodenum and rectum were obtained. In Group I, no amyloidosis was detected in gingival and GIT biopsies among 13 patients. In the remaining 29 patients AA-amyloidosis was detected in various sites with the following frequencies: duodenum 100%, rectum 83%, antrum 79%, esophagus 44% and gingiva 29%. In Group II, frequency of amyloid deposition was 97% in duodenum, 76% each in antrum and rectum, 59% in esophagus and 32% in gingival mucosa. In conclusion, duodenal biopsy is sensitive for diagnosing amyloidosis in CKD patients, and highly correlates with renal amyloidosis.
Journal of Clinical Gastroenterology | 2004
Nihat Akbayir; Gonca Gökdemir; Tülin Mansur; Mehmet Sokmen; Sevil Gündüz; Canan Alkim; Burcu Barutcuoglu; Levent Erdem
Goals and Background Hepatitis C virus (HCV) is a hepatotropic and lymphotropic virus. This agent can promote development of a panel of autoimmune diseases. The relationship between HCV infection and vitiligo, in which autoimmune mechanisms are believed to play a role is not yet elucidated. In this study we investigated HCV seropositivity in vitiligo patients and compared this with non-vitiligo population. Study A total of 102 consecutive patients with vitiligo were included in the study (47 male, 55 female, mean age: 36.8 ± 16.9 years, range: 5–75). Control population was 670 age and sex matched healthy blood donors (406 male, 264 female, mean age: 32.8 ± 11.3 years, range: 20–58). Third generation enzyme immunoassay was used for serum anti-HCV determination. When positive, qualitative confirmation was performed by HCV-RNA determination using RT-PCR. Results Anti-HCV antibody was detected only in 1 patient and confirmed by RT-PCR test. This patient was a 6-year-old girl with a non-segmental form of vitiligo, which is more frequently associated with autoimmune disorders, hence the incidence of HCV seropositivity found as 0.98%. There was no statistically significant difference between this figure and 0.6% prevalence in healthy blood donors. Conclusion Seroprevalence of HCV in vitiligo patients is not different from that of a control group in Turkey, and HCV infection may not be involved in the pathogenesis of vitiligo despite case reports showing co-existence of these 2 diseases.
Kidney & Blood Pressure Research | 2013
Murvet Yilmaz; Abdulkadir Unsal; Mehmet Sokmen; Ozlem Harmankaya Kaptanogullari; Canan Alkim; Fevziye Kabukcuoglu; Aysim Ozagari; Emire Bor
Background: The natural history of AA amyloidosis is typically progressive, leading to multiple organ failure and death. We analyzed the etiology as well as clinical and laboratory features of patients with biopsy-proven AA amyloidosis and evaluated the ultimate outcome. Methods: Seventy-three patients (24 female; mean age 41.85±15.89 years) were analyzed retrospectively. Demographic, clinical and laboratory features were studied and the outcome was assessed. Results: Familial Mediterranean Fever and tuberculosis were the most frequent causes of amyloidosis. Mean serum creatinine and proteinuria at diagnosis were 4.65±4.89 mg/dl and 8.04±6.09 g/day, respectively; and stage I, II, III, IV and V renal disease were present in 19.2%, 13.7%, 16.4%, 11%, and 39.7% of the patients, respectively. ESRD developed in 16 patients during the follow-up period. All of the ESRD patients started a dialysis programme. Thirty patients (41%) died during the follow-up period; median patient survival was 35.9±6.12 months. Old age, tuberculosis etiology, advanced renal disease and low serum albumin levels were associated with a worse prognosis. Serum albumin was a predictor of mortality in logistic regression analysis. Conclusion: The ultimate outcome of the patients with AA amyloidosis is poor, possibly due to the late referral to the nephrology clinics. Early referral may be helpful to improve prognosis.
Libyan Journal of Medicine | 2012
Canan Alkim; Damlanur Sakiz; Huseyin Alkim; Ayten Livaoglu; Tulin Kendir; Huseyin Demirsoy; Levent Erdem; Nihat Akbayir; Mehmet Sokmen
Background and aim Angiogenesis is an important process in the pathogenesis of chronic inflammation. We aimed to study the angiogeneic balance in inflammatory bowel disease (IBD) by evaluating the expression of vascular endothelial growth factor (VEGF) and thrombospondin-1 (TSP-1) on colonic epithelial cells, together with the expression of inducible nitric oxide synthase (iNOS). Methods Twenty-one ulcerative colitis (UC), 14 Crohns disease (CD), 11 colorectal cancer patients, and 11 healthy controls colonic biopsy samples were evaluated immunohistochemically. Results The expressions of TSP-1, VEGF, and iNOS in UC and CD groups were higher than expression in healthy control group, all with statistical significance. However, in colorectal cancer group, VEGF and iNOS expressions were increased importantly, but TSP-1 expression was not statistically different from healthy control groups expression. Both TSP-1 and VEGF expressions were correlated with iNOS expression distinctly but did not correlate with each other. Conclusions Both pro-angiogeneic VEGF and antiangiogeneic TSP-1 expressions were found increased in our IBD groups, but in colorectal cancer group, only VEGF expression was increased. TSP-1 increases in IBD patients as a response to inflammatory condition, but this increase was not enough to suppress pathologic angiogenesis and inflammation in IBD.