Browsing by Author "Ozcelik, Umit"

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Analysis of Panel Reactive Antibodies in Renal Transplant Recipients Detected by Luminex: A Single-Center Experience
(2016) Inal, Ali; Ozcelik, Umit; Uyanik, Ebru Ogan; Kulah, Eyyup; Demirag, Alp; 0000-0002-0690-2529; 0000-0003-1073-2494; 0000-0001-6041-4254; 26517205; J-8056-2012; AAG-8651-2021; AAJ-5764-2021
Objectives: The role of panel reactive antibody has gained universal acceptance in solid-organ transplant. This parameter is used to gauge the level of sensitization of prospective solid-organ recipients. More than one-third of patients on wait lists for kidney transplant are sensitized. Most have previously formed donor-specific and non-donor-specific serum antibodies and/or positive crossmatch by complementdependent cytotoxicity and/or flow cytometry. We present the rate of positivity at our institution for human leukocyte antigen antibodies and describe the condensation of antibodies in human leukocyte antigens for renal pretransplant recipients. Materials and Methods: Between January 2011 and December 2012, six hundred twenty consecutive renal transplant recipients on the wait list at the Baskent University were evaluated for this retrospective study. Panel reactive antibody screening and definition tests were studied with Luminex assays for the combination of class I (A, B, C) and class II antigens (DR, DQ). Results: We found a panel reactive antibody screening positivity in 20.4% of our patients on renal transplant waiting list. Panel reactive antibody defining tests were meaningful in 12.2% of the whole list. We observed that only panel reactive antibody class I positivity was seen in 2.2%, only panel reactive antibody class II positivity was seen in 2.7%, and both panel reactive antibody class I and class II positivities were seen in 7.2% of the defining tests. Conclusions: The estimated risk of sensitization for patients with a living donor is determined from the combined results of the crossmatch with the donor and those of the recipient's panel reactive and donorspecific antibodies. Compared with complementdependent cytotoxicity crossmatch, Luminex assays provide greater sensitivity and specificity in detection of donor-specific antibodies.
Are there any differences between age groups regarding colorectal surgery in elderly patients?
(2014) Bircan, Huseyin Yuce; Koc, Bora; Ozcelik, Umit; Adas, Gokhan; Karahan, Servet; Demirag, Alp
Background: Surgical procedures with curative or palliative intentions in subjects aged over 70 represent a colorectal surgical challenge due to the issue they raise: Benefits versus increased morbidity. In this study, we proposed to compare the impact of surgery with the surgical intervention short-term results and analyze the factors that may influence these results in elderly age groups. Methods: We retrospectively analyzed a database containing information about patients who underwent colorectal surgery from January 2008 to December 2013 at the Baskent University Istanbul Research Hospital and the Okmeydani Training and Research Hospital. Results: A total of 265 patients were enrolled and analyzed in this retrospective study. Of these patients operated during the study period, 110 were between 60 and 69 years of age (group 1), 99 were between 70 and 79 years of age and 56 were older than 80 years of age. In total, there were 138 (52%) men and 127 (48%) women that underwent colorectal surgery. Intraoperative complications did not differ between group 1 and group 2, group 2 and group 3; however, some differences were observed between group 1 and group 3 (p = 0.001). Systemic complications were more frequent in group 3 than in groups 1 (p = 0.039) and 2 (p = 0.002). Furthermore, there were no significant systemic complication differences between groups 1 and 2. The mean length of postoperative hospital stay was 9.91 +/- 2.65 days in the first group, 9.38 +/- 2.44 days in the second group and 11.8 +/- 4.35 days in the third group. Conclusion: Colon surgery for both malignant and non-malignant diseases can be performed safely in different elderly age groups; thus, age should not be considered as an obstacle in elderly patients undergoing colorectal resection.
Delaying Renal Transplant after Radical Prostatectomy for Low-Risk Prostate Cancer
(2015) Ozcelik, Umit; Bircan, Huseyin Yuce; Karakayali, Feza; Moray, Gokhan; Demirag, Alp; 0000-0002-1874-947X; 0000-0003-1073-2494; 0000-0003-2498-7287; 26640918; AAB-3888-2021; AAG-8651-2021; AAE-1041-2021; R-6394-2019
To minimize the recurrence of a previously treated neoplasm in organ recipients, a period of 2 to 5 years without recurrence is advocated for most malignancies. However, prostate cancer is different because of its biological properties, diagnosis, and treatment. Most prostate cancers are detected at a low stage and demonstrate slow growth after detection. Definitive treatment with radical prostatectomy affords excellent results. Renal transplant candidates with early-stage prostate cancer have a higher risk of dying on dialysis than dying from prostate cancer; therefore, renal transplant candidates with organ-confined prostate cancer should be immediately considered for transplant.
Development of an Information Model for Kidney Transplant Wait List
(2015) Bircan, Huseyin Yuce; Ozcelik, Umit; Uysal, Nida; Demirag, Alp; Haberal, Mehmet; 0000-0003-1073-2494; 0000-0002-3462-7632; 26640914; R-6394-2019; AAG-8651-2021; AAJ-8097-2021
Objectives: Deceased-donor kidney transplant is unique among surgical procedures that are an urgent procedure performed in an elective population. It has not been possible to accurately determine when a given patient will be called for transplant. Patients on the active transplant list can be called for a transplant at any time. As a result, every effort must be made to optimize their health according to best practices and published clinical practice guidelines. Materials and Methods: Once the patient is placed on the transplant wait list after undergoing an initial extensive evaluation, continued surveillance is required. Therefore, we developed a kidney transplant wait list surveillance software program that alerts organ transplant coordinator on time regarding which patients need a work-up. Results: The new designed software has a database of our waiting patients with their completed and pending controls. The software also has built-in functions to warn the responsible staff with an E-mail. If one of the controls of a recipient delayed, the software sends an automated E-mail to the staff regarding the patients delayed controls. The software is a Web application that works on any platform with a Web browser and Internet connection and allows access by multiple users. The software has been developed with NET platform. The database is SQL server. The software has the following functions: patient communication info, search, alert list, alert E-mail, control entry, and system management. Conclusions: As of January 2014, a total of 21 000 patients were registered on the National Kidney Transplant wait list in Turkey and the kidney transplant wait list had been expanding by 2000 to 3000 patients each year. Therefore computerized wait list programs are crucial to help to transplant centers to keep their patients up-to-date on time.
Effect of Topical Platelet-Rich Plasma on Burn Healing After Partial-Thickness Burn Injury
(2016) Ozcelik, Umit; Ekici, Yahya; Bircan, Huseyin Yuce; Aydogan, Cem; Turkoglu, Suna; Ozen, Ozlem; Moray, Gokhan; Haberal, Mehmet; 27262706
Background: To investigate the effects of platelet-rich plasma on tissue maturation and burn healing in an experimental partial-thickness burn injury model. Material/Methods: Thirty Wistar albino rats were divided into 3 groups of 10 rats each. Group 1 (platelet-rich plasma group) was exposed to burn injury and topical platelet-rich plasma was applied. Group 2 (control group) was exposed to burn injury only. Group 3 (blood donor group) was used as blood donors for platelet-rich plasma. The rats were killed on the seventh day after burn injury. Tissue hydroxyproline levels were measured and histopathologic changes were examined. Results: Hydroxyproline levels were significantly higher in the platelet-rich plasma group than in the control group (P=.03). Histopathologically, there was significantly less inflammatory cell infiltration (P=.005) and there were no statistically significant differences between groups in fibroblast development, collagen production, vessel proliferations, or epithelization. Conclusions: Platelet-rich plasma seems to partially improve burn healing in this experimental burn injury model. As an initial conclusion, it appears that platelet-rich plasma can be used in humans, although further studies should be performed with this type of treatment.
Effects of Natural Immune System on Acute Rejection of Living Donor Renal Transplantation
(2016) Kirnap, Mahir; Yalcin, Yaprak; Ozcelik, Umit; Ekici, Yahya; Fatac, Belgin; Moray, Gokhan; Haberal, Mehmet; https://orcid.org/0000-0002-9337-9106; https://orcid.org/0000-0003-1073-2494; https://orcid.org/0000-0003-2498-7287; https://orcid.org/0000-0002-3462-7632; AAH-9198-2019; ABB-4078-2020; AAG-8651-2021; AAE-1041-2021; AAJ-8097-2021
Increased Mortality Among Renal Transplant Patients With Invasive Pulmonary Aspergillus Infection
(2018) Balcan, Baran; Ozcelik, Umit; Ugurlu, Aylin Ozsancakli; Aydin, Mehtap; Nalcaci, Serdar; Karakayali, Feza Yarbug; 0000-0003-1073-2494; 0000-0003-3598-3986; 0000-0003-4044-9366; 0000-0002-1874-947X; 30235978; A-4721-2018; AAG-8651-2021; AAA-2925-2020; HLX-0937-2023; AAB-3888-2021
Introduction: Renal transplantation is the most effective and preferred definite treatment option in patients with end-stage renal disease. Due to long-term immunesuppressive treatment, renal transplant recipients become vulnerable to opportunistic infections, especially to fungal infections. Method: This was a single-center, retrospective observational study of 438 patients who underwent renal transplantation between 2010 and 2016. Results: Thirty-eight renal transplant recipients who had lower respiratory tract infection with median age of 41.5 years were evaluated for invasive pulmonary aspergillus (IPA). Of these, 52.6% were female and 84.2% had living donors. Eleven of 38 lower respiratory patients were found to have IPA infection, 5 with proven infection. Compared to patients who did not have fungal pulmonary infection, patients with invasive aspergillus were older and had high fever, galactomannan levels, and leukocyte counts. Mortality was also higher in those patients. Having fever at the baseline and IPA infection was significantly associated with mortality in univariate analysis and remained related in multivariate model after adjustment for age, gender, and fever. Conclusion: Invasive pulmonary aspergillus infection is highly associated with increased mortality rates in renal transplant patients. Fungal pulmonary infections in immune-suppressed patients should be diagnosed and treated immediately in order to avoid the life-threatening complications and may greatly improve prognosis.
Influence of Various Living Donor Kidney Measurements in Relation to Recipient Body Measurements on Posttransplant Allograft Functional Outcomes
(2018) Kulah, Eyup; Ozcelik, Umit; Isiklar, Iclal; Cevik, Halime; Bircan, Huseyin Yuce; Karakayali, Feza Y.; Haberal, Mehmet; https://orcid.org/0000-0001-6041-4254; https://orcid.org/0000-0003-1073-2494; https://orcid.org/0000-0002-1874-947X; https://orcid.org/0000-0002-3462-7632; 27356006; AAJ-5764-2021; AAG-8651-2021; R-6394-2019; AAB-3888-2021; AAJ-8097-2021
Objectives: Donor kidney measurements may affect outcomes of transplanted allografts. We tested allograft and recipient measurements on kidney allograft outcomes. In this study, we compared the effects of kidney allograft volumes, which were measured using computed tomographic angiography before transplant, and allograft weight, which was measured during surgery, in relation to the recipient's body weight and body mass index on kidney function at 6 and 12 months after transplant. Material and Methods: We included 74 patients (40 female and 34 male patients, mean age of 50.42 +/- 9.75 y) in this study. Results: Intraoperative allograft weight was 182.68 +/- 40.33 g (range, 104-266 g). The allograft volume measured using computed tomographic angiography scanning was 123.34 +/- 24.26 ml (range, 78-181 ml). The estimated glomerular filtration rates of the recipients at 6 and 12 months after transplant correlated negatively with age and recipient body mass index but correlated positively with allograft volume/recipient body weight, allograft volume/recipient body mass index, allograft weight, allograft weight/recipient body weight, and allograft weight/recipient body mass index values, as concluded by univariate analyses. From multivariate analyses, we found variables of interest presumed to significantly affect the 12-month estimated glomerular filtration rates, including recipient age, allograft volume/recipient body weight, allograft volume/recipient body mass index, allograft weight, allograft weight/recipient body weight, and allograft weight/recipient body mass index. Conclusions: Transplanted allograft and recipient body values may be used as predictors of estimated glomerular filtration rates 6 and 12 months after transplant.
Multiple Brain Abscesses Due to Phialemonium in a Renal Transplant Recipient: First Case Report in the Literature
(2015) Aydin, Mehtap; Ozcelik, Umit; Cevik, Halime; Cinar, Ozlem; Evren, Ebru; Demirag, Alp; 0000-0003-1073-2494; 0000-0003-4044-9366; 26640919; AAG-8651-2021; HLX-0937-2023; JAZ-1759-2023
Fungal brain abscesses are a rare but serious complication in transplant recipients. Phialemonium organisms are rare causes of invasive mold infections. Here, we present the first case of a renal transplant recipient with multiple brain abscesses caused by Phialemonium infection A. A 51-year-old female kidney transplant recipient was admitted with pneumonia of an unknown cause and treated with empiric intravenous antibiotics. Her treatment was uneventful, and she was discharged 1010 days later. After 5 days, she was readmitted with fever, cerebral palsy, and speech disorder. The patient had undergone living-donor renal transplant 7 months earlier. A cranial computed tomography and magnetic resonance imaging were performed for a possible cerebro vascular pathology. The magnetic resonance imaging scan showed multiple brain abscesses located at the left parietal, frontal and occipital lobes; right parietal and occipital lobes; right basal ganglia; and left cerebellum. The patient received meropenem, linezolid, sulfamethoxazole and trimethoprim, and AmBisome for probable pathogenic infection, and immunosuppressive agents dosage was reduced increasingly immuno suppressed. We identified Phialemonium in cerebrospinal fluid culture. The patient received voriconazole 200 mg twice daily. Lesions could not be drained due to lack of capsula formation. The patient died on the 30th day of antifungal therapy. Phialemonium organisms, although a rare cause of fungal infections, are associated with a high mortality rate in immunocompromised patients. To our knowledge, this is the first case report in the literature describing multiple brain abscesses due to Phialemonium in a transplant recipient. Clinicians recipient should be alert about these rare opportunistic fungi in the differential diagnosis of brain abscess, and bronchoscopy and broncho alveolar lavage are recommended for transplant patients when they are admitted with pneumonia exclude fungal infections.
Our Experience with Paired Kidney Exchange Transplantation
(2018) Haberal, Mehmet; Akdur, Aydincan; Karakayali, Feza Yarbug; Ozcelik, Umit; Moray, Gokhan; Kulah, Eyyup; Inal, Ali; Torgay, Adnan; Arslan, Gulnaz; 0000-0002-3462-7632; 0000-0002-8726-3369; 0000-0002-1874-947X; 0000-0003-1073-2494; 0000-0003-2498-7287; 0000-0001-6041-4254; 0000-0002-0690-2529; 0000-0002-6829-3300; AAJ-8097-2021; AAA-3068-2021; AAB-3888-2021; AAG-8651-2021; AAE-1041-2021; AAJ-5764-2021; J-8056-2012; AAJ-5221-2021
The Outcomes of Ultralow Anterior Resection or an Abdominoperineal Pull-Through Resection and Coloanal Anastomosis for Radiation-Induced Recto-Vaginal Fistula Patients
(2016) Karakayali, Feza Yarbug; Tezcaner, Tugan; Ozcelik, Umit; Moray, Gokhan; https://orcid.org/0000-0002-1874-947X; https://orcid.org/0000-0002-3641-8674; https://orcid.org/0000-0003-1073-2494; https://orcid.org/0000-0003-2498-7287; 26628070; AAB-3888-2021; AAD-9865-2021; AAG-8651-2021; AAE-1041-2021
The purpose of this study was to evaluate the outcomes of patients who underwent colorectal resections and coloanal anastomosis for radiation-induced recto-vaginal fistulas (RVFs). The effect of the surgical treatment technique on bowel function, fecal continence, and quality of life of patients was also evaluated. Twenty-one female patients, who received adjuvant chemotherapy and external beam pelvic radiation for cervix carcinoma after radical hysterectomy + pelvic/paraaortic lymph node dissection, having RVF but without tumor recurrence, were included. All patients underwent an ultralow anterior resection (n = 11) or an abdominoperineal pull-through resection and straight coloanal anastomosis (n = 10). A bowel functions questionnaire and a Fecal Incontinence Quality of Life (FIQLI) questionnaire were applied to patients pre-operatively and also 6 months after the ileostomy closure procedures. No recurrent RVF was observed in a mean follow-up period of 20 months after ostomy reversal procedures. The FIQLI depression, lifestyle, and embarrassment scores were significantly improved on the follow-up questionnaire. The mean pre- and post-operative incontinence scores were not significantly different. The spontaneous closure rate after a simple diverting stoma is quite low and local repair procedures usually result in failure. In selected patients, performing a nearly total rectum resection and maintaining the intestinal continuity with a coloanal anastomosis may be accepted as a safe and curative option. Recurrence-free outcome and the improvement of the quality of life of the patients represent the efficiency of this treatment modality.
Rectal diverticulitis mimicking rectal carcinoma with intestinal obstruction: Case report
(2015) Ozcelik, Umit; Bircan, Huseyin Yuce; Eren, Eryiğit; Demiralay, Ebru; Isiklar, Iclal; Demirag, Alp; Moray, Gokhan; 25698274
Although diverticular disease of the colon is common, the occurrence of rectal diverticula is extremely rare with only sporadic reports in the literature since 1911. Symptomatic rectal diverticula are seen even less frequently, and surgical intervention is needed for only complicated cases. Here we report the case of a 63-year-old woman presenting with rectal diverticulitis mimicking rectal carcinoma with intestinal obstruction.
Results of BK Virus Screening in Renal Transplant Recipients
(2016) Ozcelik, Umit; Bircan, Huseyin Yuce; Aydin, Mehtap; Kulah, Eyyup; Karakayali, Feza Yarbug; Haberal, Mehmet; https://orcid.org/0000-0003-1073-2494; https://orcid.org/0000-0003-4044-9366; https://orcid.org/0000-0002-1874-947X; https://orcid.org/0000-0002-3462-7632; AAG-8651-2021; R-6394-2019; HLX-0937-2023; AAB-3881-2021; AAB-3888-2021; AAJ-8097-2021
Results of Paired Kidney Exchange Transplantation: Initial Experience of A Single Institution
(2016) Karakayali, Feza; Ozcelik, Umit; Akdur, Aydincan; Bircan, Huseyin Y.; Yildirim, Sedat; Moray, Gokhan; Haberal, Mehmet; https://orcid.org/0000-0002-1874-947X; https://orcid.org/0000-0003-1073-2494; https://orcid.org/0000-0002-8726-3369; https://orcid.org/0000-0002-5735-4315; https://orcid.org/0000-0003-2498-7287; https://orcid.org/0000-0002-3462-7632; AAB-3888-2021; AAG-8651-2021; AAA-3068-2021; R-6394-2019; AAF-4610-2019; AAE-1041-2021; AAJ-8097-2021
Surgical Complications After Kidney Transplantation
(2016) Haberal, Mehmet; Boyvat, Fatih; Akdur, Aydincan; Kirnap, Mahir; Ozcelik, Umit; Karakayali, Feza Yarbug; 0000-0002-3462-7632; 0000-0002-8726-3369; 0000-0003-1073-2494; 0000-0002-1874-947X; 27934557; AAJ-8097-2021; F-4230-2011; AAA-3068-2021; AAH-9198-2019; AAG-8651-2021; AAB-3888-2021
Since the first successful organ transplant conducted between twins in 1954, kidney transplant has evolved considerably over the past 50 years. Kidney transplant plays an important role in the treatment of end-stage kidney disease to improve the quality of life and prolong the life of patients. Despite significant advances, postoperative medical and surgical complications still represent important causes of morbidity and mortality. Many problems can be avoided through prophylactic correction of abnormalities detected during the preoperative evaluation; however, it is critical that technical mishaps at all stages of the transplant process (donor nephrectomy, benchwork preparation, and implant) be prevented and that careful postoperative monitoring be carried out, including thorough examination by attending physicians. However, despite these advances, surgical complications still present serious problems in kidney transplant recipients.
Surgical Treatment for Ureteral Obstruction After Kidney Transplantation
(2018) Haberal, Mehmet; Boyvat, Fatih; Akdur, Aydincan; Kirnap, Mahir; Ozcelik, Umit; Karakayali, Feza Yarbug; 0000-0002-3462-7632; 0000-0002-8726-3369; 0000-0003-1073-2494; 0000-0002-1874-947X; AAJ-8097-2021; F-4230-2011; AAA-3068-2021; AAH-9198-2019; AAG-8651-2021; AAB-3888-2021
Use of Biological Prosthesis in a Patient With Kidney and Pancreas Transplant and a Giant Incisional Hernia: Case Report
(2015) Ozcelik, Umit; Cevik, Halime; Bircan, Huseyin Yuce; Demirag, Alp; 0000-0003-1073-2494; 0000-0001-7276-3240; 25894161; AAG-8651-2021; R-6394-2019; JWP-7324-2024
Objectives: The use of synthetic mesh in transplant patients is controversial. Recent studies have shown that biological prostheses have a greater ability to integrate into tissues, resist bacterial colonization, and reduce cytotoxic or allergic reactions, and provide similar functional results, compared with synthetic prostheses. Biological prostheses do not require any reduction or discontinuation of immunosuppressive therapy. We present the case of a kidney and pancreas transplant recipient who had a giant incisional hernia that was treated successfully with a biological prosthesis. Case Report: A 40-year-old male kidney and pancreas transplant recipient was admitted to our hospital with a giant incisional hernia, 2 years after transplant. The defect on the abdominal wall was 40 x 30 cm. We used 2 biological prostheses (40 x 20 cm and 30 x 20 cm) to close the abdominal wall. The patient was discharged on postoperative day 5 without complications. An abdominal magnetic resonance imaging scan showed complete integrity of the biological prostheses at 1 year after surgery. Conclusions: Transplant recipients have higher risks with use of synthetic prostheses because of being immunosuppressed, compared with other patients. Recent studies show that biological prostheses provided similar functional results without complications compared with synthetic prostheses. These prostheses are versatile and do not require any changes in immunosuppressive therapy. Therefore, they seem to be a better option than synthetic prostheses. In our opinion, biological prostheses are more safe, effective, and reliable than synthetic prostheses, especially for large incisional hernias in transplant recipients. We believe that further larger studies can support our opinion.