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Dive into the research topics where Kerem Karaman is active.

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Featured researches published by Kerem Karaman.


Hepato-gastroenterology | 2012

The role of mean platelet volume in the diagnosis of hepatocellular carcinoma in patients with chronic liver disease.

Mevlut Kurt; Ibrahim Koral Onal; Abdurrahim Sayilir; Yavuz Beyazit; Erkin Oztas; Murat Kekilli; Nesrin Turhan; Kerem Karaman; Meral Akdogan

BACKGROUND/AIMS Hepatocellular carcinoma (HCC) has poor long-term prognosis so we need new diagnostic techniques and markers to detect HCC in the early phases. The aim of this study was to analyze the levels of serum mean platelet volume in HCC. METHODOLOGY The clinical data of 230 subjects with normal, chronic hepatitis, cirrhosis and HCC were retrospectively analyzed at our hospital between January 2009 and December 2009. The levels of MPV were determined in patients with liver disease and compared between patient groups and with healthy persons. RESULTS Serum MPV levels were significantly increased compared to the patients with chronic hepatitis, cirrhosis, and the control group (p<0.01). The cut-off value for MPV for the detection of HCC in cirrhotic patients was calculated as ≥9.2fl using ROC analysis [Sensitivity: 68.3%, specificity: 62.1%, AUC: 0.676 (0.580-0.773), p<0.001]. Additionally, serum MPV levels show higher sensitivity for diagnosis of HCC than AFP. An AFP of more than 7.4IU/mL and an MPV of ≥9.2fl, both put together, had a specificity of 95.2%, while when used separately, they have a sensitivity of 87.5%. CONCLUSIONS MPV may be a potential or adjunctive marker of HCC in patients with chronic liver disease.


European Journal of Internal Medicine | 2011

The predictive value of mean platelet volume in differential diagnosis of non-functional pancreatic neuroendocrine tumors from pancreatic adenocarcinomas

Kerem Karaman; Erdal Birol Bostanci; Erol Aksoy; Mevlut Kurt; Bahadir Celep; Murat Ulas; Tahsin Dalgic; Ali Surmelioglu; Mutlu Hayran; Musa Akoglu

OBJECTIVE The aim of the present study is to evaluate in a retrospective manner the diagnostic value of mean platelet volume (MPV) in pancreatic adenocarcinomas and pancreatic neuroendocrine tumors (PNETs). PATIENTS AND METHODS A total of 92 patients, who were admitted for pancreatic adenocarcinoma (n=76) and PNET (n=16) between March 2007 and December 2009, were analyzed retrospectively for demographics and clinical information. RESULTS Thirty-nine patients (51.3%) had a resectable, whereas 37 patients (48.7%) had an unresectable pancreatic adenocarcinoma. Nine patients (56.3%) had a non-functional PNET, 6 patients (37.5%) had an insulinoma, and the remaining one patient had a gastrinoma. The mean age was 59.3±10.5 for pancreatic adenocarcinomas and 45.1±10.6 for PNETs. The mean age at diagnosis was significantly higher in patients with pancreatic adenocarcinomas than the patients with PNET (p<0.001). Preoperative mean hemoglobin levels were significantly lower in patients with pancreatic adenocarcinoma than those with PNET (12.4±1.8g/dl vs 13.7±2.2g/dl), (p<0.013). The preoperative median MPV levels were significantly lower in patients with PNET 7.8fL (7.2-9.4) than in patients with pancreatic adenocarcinomas 8.6fL (6.6-13.5), (p<0.014). In subgroup analysis, a significant difference in MPV levels was mainly caused by the difference between pancreatic adenocarcinomas and non-functional PNETs (p=0.017). The cut-off value of MPV level for detection of PNETs was calculated as≤7.8fL using ROC analysis [Sensitivity: 66.7%, specificity: 75.9%, AUC: 0.734 (0.587-0.880) p=0.022]. In logistic regression analysis, independent predictive factors for determining PNETs in the differential diagnosis of pancreatic adenocarcinomas were calculated as age (OR=0.068, 95% CI: 0.012-0.398), Ca 19-9 (OR=0.039, 95% CI: 0.006-0.263), MPV (OR=0.595, 95% CI: 0.243-1.458), and hemoglobin (OR=1.317, 95% CI: 0.831-2.086). CONCLUSION Age, Ca 19-9, MPV, and hemoglobin levels have diagnostic value for distinguishing PNETs from pancreatic adenocarcinomas.


Journal of Laparoendoscopic & Advanced Surgical Techniques | 2010

Predictive Factors for Conversion to Open Surgery in Patients Undergoing Elective Laparoscopic Cholecystectomy

Metin Ercan; E. Birol Bostanci; Zafer Teke; Kerem Karaman; Tahsin Dalgic; Murat Ulas; Ilter Ozer; Yusuf B. Ozogul; Fuat Atalay; Musa Akoglu

BACKGROUND Laparoscopic cholecystectomy (LC) has become the standard surgical procedure for symptomatic gallbladder disease. The aim of this study was to identify factors that may be predictive of cases that would require a conversion to laparotomy. METHODS In the period of 2002-2007, 2015 patients who underwent elective LC were included in the study. Patients were divided into two groups. Group 1 (n = 1914) consisted of patients whose operation was successfully completed with LC. Group 2 (n = 101) consisted of patients who had a conversion. A prospective analysis of parameters, including patient demographics, laboratory values, radiologic data, and intraoperative findings, was performed. Multivariate stepwise logistic regression was used to determine those variables predicting conversion. RESULTS One-hundred and one (5.0%) patients required a conversion. Significant predictors of conversion to open cholecystectomy in univariate analysis were increasing age, male gender, previous upper abdominal or upper plus lower abdominal incisions, an elevated white blood cell count, high aspartate transaminase, alkaline phosphatase and total bilirubin levels, preoperative ultrasound findings of a thickened gallbladder wall and dilated common bile duct, preoperative endoscopic retrograde cholangiopancreatography (ERCP), high-grade adhesion, and scleroatrophic appearance of the gallbladder intraoperatively. Multivariate analysis revealed that a history of previous abdominal surgery, preoperative ERCP, high-grade adhesion, and scleroatrophic appearance of the gallbladder predicted conversion. CONCLUSIONS Patient selection is very important for efficient, safe training in LC. Based on the presented data, pathways could be suggested that enable the surgeon to precisely decide, during LC, when to convert to open surgery.


Journal of Investigative Surgery | 2010

Topical Ankaferd Application to Presacral Bleeding due to Total Mesorectal Excision in Rectal Carcinoma

Kerem Karaman; Erdal Birol Bostanci; Metin Ercan; Mevlut Kurt; Zafer Teke; Enver Reyhan; Musa Akoglu

Kerem Karaman, MD, Erdal Birol Bostanci, MD, and Metin Ercan, MD Department of Gastroenterological Surgery, Turkiye Yuksek Ihtisas Teaching and Research Hospital, Ankara, Turkey Mevlut Kurt, MD Department of Gastroenterology, Turkiye Yuksek Ihtisas Teaching and Research Hospital, Ankara, Turkey Zafer Teke, MD, Enver Reyhan, MD, and Musa Akoglu, MD Department of Gastroenterological Surgery, Turkiye Yuksek Ihtisas Teaching and Research Hospital, Ankara, Turkey


Journal of Laparoendoscopic & Advanced Surgical Techniques | 2012

Surgical Outcome of Patients with Perforation After Endoscopic Retrograde Cholangiopancreatography

Metin Ercan; Erdal Birol Bostanci; Tahsin Dalgic; Kerem Karaman; Yusuf B. Ozogul; Ilter Ozer; Murat Ulas; Erkan Parlak; Musa Akoglu

BACKGROUND The most important criterion in the management of endoscopic retrograde cholangiopancreatography (ERCP)-related perforations is the delineation of the injury pattern. The aim of the present study was to evaluate in a retrospective manner the patients who undergo surgery due to ERCP-related perforations. PATIENTS AND METHODS Between January 2006 and December 2010, a total of 9209 ERCPs were performed at Turkiye Yuksek Ihtisas Teaching and Research Hospital, Ankara, Turkey. From these, perforation was diagnosed in 52 patients (0.56%). Twenty-four patients (46.2%) underwent surgery. Patients were evaluated according to age, gender, ERCP indication, comorbid disease, the time between diagnosis and perforation, the time between ERCP and surgical intervention, radiological and clinical signs, localization of the perforation, surgical procedure, hospitalization period, and postoperative outcome. RESULTS Twenty-four patients underwent surgery. Thirteen patients (54.1%) had lateral duodenal wall perforation, 4 patients (16.7%) had perforation in the afferent loop (these patients had Billroth-II gastroenterostomy at ERCP admission), 2 patients (8.3%) had bile duct perforation, and 1 patient (4.1%) had esophageal perforation. In 4 patients (16.7%), the localization of the perforation could not be found. Nine patients (37.5%) died in the postoperative period. Six patients had lateral duodenal wall perforation, 2 patients had afferent loop perforation, and one patient had esophagus perforation. Three patients died of nonsurgical reasons (myocardial infarction, serebrovascular occlusion, and cardiac dysrhythmia). CONCLUSIONS Duodenal wall perforations have a serious fatal outcome even if early surgical intervention is performed. In contrast to duodenal wall injuries, perivaterian and choledochal injuries have a better outcome.


American Journal of Surgery | 2013

Effects of dexamethasone and pheniramine hydrogen maleate on stress response in patients undergoing elective laparoscopic cholecystectomy

Kerem Karaman; Erdal Birol Bostanci; Erol Aksoy; Murat Ulas; Tuba Yigit; Mehmet Ozcan Erdemli; Ugur Ercin; Ayse Bilgihan; Gul Saydam; Musa Akoglu

BACKGROUND Laparoscopic cholecystectomy (LC) still leads to significant postoperative nausea and vomiting (PONV) and pain. Our aim was to evaluate the efficacy of dexamethasone or pheniramine hydrogen maleate, either alone or combined, in reducing the stress response and symptoms after LC. METHODS Patients were randomly assigned to 1 of 4 groups, each consisting of 20 patients: control, dexamethasone (8 mg/2 mL), pheniramine hydrogen maleate (45.5 mg/2 mL), and the combined group. The drugs were given before anesthesia induction. RESULTS C-reactive protein levels (CRP) and visual analog scale (VAS) scores were significantly less in the dexamethasone (P = .003) and combined groups (P < .001). Both dexamethasone (P < .001) and pheniramine hydrogen maleate (P = .005) significantly reduced PONV. CONCLUSIONS Dexamethasone significantly reduced postoperative pain and the systemic acute-phase response, whereas these effects were only partially attained with pheniramine hydrogen maleate. Both dexamethasone and pheniramine hydrogen maleate significantly reduced PONV. An additive effect seemed to occur if these drugs were used in combination.


Hepato-gastroenterology | 2011

Management of choledochal cysts in adults: a retrospective analysis of 23 patients.

Murat Ulas; Erdal Polat; Kerem Karaman; Tahsin Dalgic; Metin Ercan; Ilter Ozer; Zafer Teke; Yusuf B. Ozogul; Erdal Birol Bostanci; Erkan Parlak; Musa Akoglu

BACKGROUND/AIMS Choledochal cysts are rare congenital anomalies of the pancreaticobiliary system, whose etiology remains unknown. We aimed to review patients with choledochal cysts and to compare our results with current literature. METHODOLOGY Twenty-three patients diagnosed as having choledochal cysts between January 2004 and July 2010 were evaluated retrospectively. RESULTS Thirteen patients had type I (56.5%), 3 patients type II (13%), 3 patients type III (13%), 1 patient type IV-A (8.3%) and the remaining 3 patients had type V (13%) choledochal cysts. All patients with type I cysts underwent cyst excision with Roux-en-Y hepaticojejunostomy. Two patients with type II cysts underwent cyst excision with choledochoduodenostomy, whereas cyst excision with T-tube drainage was applied to the other. Endoscopic unroofing was performed type III cysts. The patient with type IV-A cyst was not eligible for surgery due to low cardiopulmonary performance status but ERCP was applied successfully more than 3 times for the extraction of the stones which fell from the intrahepatic ducts into the common bile duct. Patients with Type V cysts underwent left hepatectomy, choledocoduodenostomy and cadaveric liver transplantation, respectively. Wound infection developed in 5 patients and anastomotic leakage occurred in 3; one died from sepsis. CONCLUSIONS Choledochal cysts are rare congenital malformations. Although treatment varies depending on the type of the cysts, complete excision of the cysts should be performed if possible.


Hepato-gastroenterology | 2012

Endoscopic and pathological aspects of gastric polyps: a Turkish referral center study.

Murat Kekilli; Yavuz Beyazit; Kerem Karaman; Abdurrahim Sayilir; Mevlut Kurt; Ibrahim Koral Onal; Yesil Y; Meral Akdogan; Sasmaz N

BACKGROUND/AIMS The aim of the present study was to retrospectively analyze all the polyps of patients undergoing endoscopic polypectomy or forceps biopsy according to their types, frequency, localization, number and gender distribution. METHODOLOGY Data from patients who underwent upper endoscopy in the Türkiye Yüksek Ihtisas Postgraduate Research Hospital between March 2007 and November 2009 were analyzed retrospectively. Forceps biopsy or polypectomy were performed for all polypoid lesions that were identified during the endoscopy. RESULTS In the study period, 14,935 patients underwent 18,522 upper endoscopies. After excluding cirrhotic patients, and patients with a history of prior gastrectomy, chronic gastritis and edema or congestion, the remaining 124 (0.83%) patients with gastric polyps were included in the study. Histopathologically, the most frequently diagnosed polyps were hyperplastic polyps (55.6%). Fundic gland polyps (9.7%), foveolar hyperplasia (8.1%) and inflammatory polyps (7.3%) were also frequent. Adenocarcinoma was more frequently seen in males, whereas hyperplastic polyps and carcinoid tumors were found more often in females, and this difference was statistically significant (p<0.009). CONCLUSIONS Results of the present study indicate that hyperplastic polyps make up the largest group. Although there is widespread PPI use, no increases in the frequency of fundic gland polyps were observed. However, increases in the ratio of carcinoid tumors suggest a suspicion of tumor development with PPI use.


Surgery Today | 2011

Mannitol attenuates acute lung injury induced by infrarenal aortic occlusion-reperfusion in rats

Zafer Teke; Fahri Adali; E. Canan Kelten; Yasar Enli; K. Gokhan Sackan; Kerem Karaman; Metin Akbulut; Ibrahim Goksin

PurposeMannitol is used as a treatment for ischemia/reperfusion (IR) injury of various organs in humans, despite the fact that its effectiveness in vivo is still disputed. The purpose of this study was to determine the effects of mannitol on acute lung injury (ALI) induced by infrarenal aortic occlusion.MethodsMale Wistar-albino rats were allocated into five groups: (i) sham-operated group, which received a laparotomy without IR injury (n = 12); (ii) IR group, which received 3 h of ischemia followed by 2 h of reperfusion (n = 12); (iii) IR + inferior caval phlebotomy (ICP) group, which was identical to group 2 except for 1 ml of blood aspiration from the inferior caval vein (n = 12); (iv) IR + mannitol-treated group, for which rats were subjected to IR and received a bolus injection of mannitol (n = 12); and (v) IR + ICP + mannitol-treated group, which underwent the same procedures as described for the previous groups. Arterial blood gas parameters were studied and bronchoalveolar lavage (BAL) was performed. Evans blue dye was injected into half of the rats. We biochemically assessed the degree of pulmonary tissue injury by investigating oxidative stress markers and enzymatic and nonenzymatic antioxidant markers, and evaluated ALI by establishing pulmonary leukosequestration and ALI scoring, histopathologically. Pulmonary edema was estimated by using Evans blue dye extravasation and wet/dry weight ratios.ResultsHypertonic mannitol treatment significantly reduced oxidative stress markers, and significantly increased enzymatic and nonenzymatic antioxidant markers in the lung tissues (P < 0.05). Arterial blood gas parameters were significantly ameliorated (P < 0.05), the BAL cytology was significantly better (P < 0.05), pulmonary leukosequestration and ALI scores were significantly decreased (P < 0.05), and pulmonary edema was significantly alleviated (P < 0.05) by mannitol administration.ConclusionThis study clearly showed that mannitol treatment significantly attenuated the aortic IR-induced ALI. Further clinical studies are required to clarify whether mannitol has a useful role in ALI during surgeries in which IR-induced organ injury occurs.


Journal of The National Medical Association | 2010

The Relationship Between Mean Platelet Volume Levels and the Inflammation in Helicobacter Pylori Gastritis

Firdevs Topal; Kerem Karaman; Sabiye Akbulut; Nazmiye Dincer; Yasemin Dölek; Yasemin Cosgun; Özlem Yönem

Helicobacter pylori is a cause of chronic gastritis. Mean platelet volume (MPV) has been started to be used as a simple inflammatory indicator in some diseases. We have aimed especially to investigate the usability of MPV as a simple indicator that may reflect severity of inflammation in gastric mucosa. Included in the study were a total of 114 patients who visited the outpatient clinic of gastroenterology with complaint of dyspepsia. Blood MPV levels in hemogram results were evaluated. Esophagogastroduodenoscopy was performed on patients included in the study, and histological analysis was performed by obtaining 2 specimens from each of antrum, corpus, and incisura angularis. All specimens were evaluated according to the updated Sydney System. No statistically significant result was found among blood MPV levels, the intensity of H pylori, and the severity of inflammation of gastric mucosa. However, it is interesting that mean MPV levels in cases with lymphoid follicle were lower. We suggest that MPV level cannot be used as a simple marker to reflect H pylori intensity and severity of inflammation in gastric endoscopic biopsies.

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Musa Akoglu

University of Pittsburgh

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