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Papers by Aydıncan Akdur

Research paper thumbnail of Long‐term effect of eplerenone treatment in children with chronic allograft nephropathy

Pediatric Transplantation

Research paper thumbnail of Liver Transplantation Due to Fulminant Hepatic Failure

Transplantation Proceedings, 2012

Objectives. To analyze the epidemiology, causes, complications, and mortality of liver transplant... more Objectives. To analyze the epidemiology, causes, complications, and mortality of liver transplants following fulminant hepatic failure over the last 16 years. Materials and methods. We completed a descriptive analysis of 21 patients with fulminant hepatic failure and a liver transplant. In almost half of the cases, the origin of liver failure was unknown. Results. The mean age was 36 years; the study group was 47.61% female (n ϭ 10) and 52.39% male (n ϭ 11). The most common early complication was transplant rejection, which occurred in 33.3% of all patients (n ϭ 7) and was confirmed by liver biopsy; the most frequent long-term complication was autoimmune hepatitis. Two retransplantations were necessary. The total mortality rate was 38.1% (n ϭ 8) with late mortality in three patients (14.3%). Conclusions. Orthotopic liver transplantation as a treatment for fulminant hepatitis has a higher mortality rate than orthotopic liver transplantation due to other causes. It does, however, enable the survival of 62% of the patients who otherwise would have died due to liver failure. The etiology of most of the cases was unknown. We should point out the high incidence rates for transplant rejection and late autoimmune hepatitis, in addition to the possibility of hemorrhagic colonic diseases that may be associated with the condition causing liver failure. Multidisciplinary control over the patient is useful for deciding at which time a liver transplant would become the only treatment option.

Research paper thumbnail of Comparison of use of central venous catheter and arteriovenous fistula as initial vascular access in 735 patıents with end-stage renal disease

Turkish Journal of Clinics and Laboratory

Aim: Although arteriovenous fistula (AVF) has been shown as the first choice for hemodialysis (HD... more Aim: Although arteriovenous fistula (AVF) has been shown as the first choice for hemodialysis (HD), its superiority over central venous catheter (CVC) is still controversial considering the risk factors. Aim was to compare AVF and CVC, which should be is used as the first vascular access in HD. Material and Methods: Patients were divided into two groups according to the use of AVF and CVC. The groups were compared in terms of age, gender, body mass index (BMI), comorbidities, use of antiplatelet and anticoagulant agents, HD sessions per week, end stage renal disease (ESRD) duration, HD treatment duration, patency of vascular acces and number of changes. Results: When patients were grouped, 499 patients were in the CVC group and 235 patients were in the AVF group. The mean age of patients in the AVF group was higher than that of the CVC group (p=0.010). The difference between the median ESRD duration of the patients in the CVC and AVF groups was statistically significant (5 vs 6 mont...

Research paper thumbnail of COVID-19 Infections in Pediatric Renal Transplant Recipients

Experimental and Clinical Transplantation

OBJECTIVES The new coronavirus SARS-CoV-2 (COVID-19) first appeared in Turkey in March 2020, spre... more OBJECTIVES The new coronavirus SARS-CoV-2 (COVID-19) first appeared in Turkey in March 2020, spread rapidly, and caused many deaths. Although COVID-19 is mostly a respiratory disease, it can cause kidney and multiorgan failure in some cases. We believe that by sharing information about the course and effects of COVID-19 infection in kidney transplant recipients receiving long-term immunosuppressive therapy our understanding will improve. MATERIALS AND METHODS Between March 2020 and October 2021, COVID-19 was researched in kidney transplant recipients under the age of 20 years who were followed at the Başkent University Transplantation Center. We documented the clinical characteristics and prognosis of pediatric kidney transplant recipients with COVID-19 disease. RESULTS Our study group included 23 patients with COVID-19 infection from 215 pediatric kidney transplant recipients. The mean age of the patients was 14.6 ± 4.7 years; there were 9 female patients. The mean follow-up time posttransplant was 62.3 ± 43.2 months. In 13 patients (56.5%), fever was the most frequent symptom. Most patients (n = 18, 78%) had minor symptoms and recovered completely after receiving supportive treatment. Four patients (17%) required hospitalization. One was diagnosed with COVID-19 infection 1 week after being treated with rituximab for acute antibody-mediated rejection. That patient died because of significant lung disease and multiorgan failure. CONCLUSIONS Despite the fact that most of our pediatric transplant recipients had mild symptoms of COVID-19, we believe that particular caution should be observed in patients who have recently received intensive immunosuppressive medications. As a result of potential new vaccines, national immunization programs, and the emergence of novel virus strains, the clinical picture may change in the future. We believe that, as information sharing increases, we will learn more about COVID-19 in renal transplant recipients.

Research paper thumbnail of Cytomegalovirus Viremia in Solid-Organ Transplant Patients in the First Year After Transplantation

Experimental and Clinical Transplantation, Mar 1, 2022

OBJECTIVES Cytomegalovirus infection is an important problem for transplantation. Although effect... more OBJECTIVES Cytomegalovirus infection is an important problem for transplantation. Although effective antivirals for prophylaxis or preemptive therapy have reduced the severity and consequences of infection, cytomegalovirus viremia and cytomegalovirusrelated disease are still matters for patients and for graft survival. The aim of our study was to determine the frequency of cytomegalovirus infections during the first year after transplant. MATERIALS AND METHODS In this study, we analyzed the data of 252 liver and kidney transplant patients who had procedures between May 2016 and May 2020. Demographic and laboratory data of patients were recorded retrospectively and analyzed with the SPSS version 25 statistical program. RESULTS Our study included 35 liver (14%) and 217 kidney transplant recipients. The ratio of male to female was 3.8, and the median age was 41 years (range, 18-71 years). In our study group, there were 32 patients (12.7%) with cytomegalovirus DNAemia, 13 patients (5%) with cytomegalovirus syndrome, and 6 patients (2.4%) with cytomegalovirus endorgan diseases. Four patients were diagnosed with gastrointestinal disease with histopathology, and 2 patients were diagnosed with cytomegalovirus pneumonia with bronchoscopy and radiology. The mortality rate was 0.8% in the first year. CONCLUSIONS Cytomegalovirus reactivations in the first year after transplant play a critical role on graft survival in solid-organ transplant. Regular follow-up of cytomegalovirus DNAemia is crucial for modifying prophylactic and preemptive antiviral regimens.

Research paper thumbnail of A model for acute kidney injury in severe burn patients

Burns, 2022

INTRODUCTION In patients with severe burns, morbidity and mortality are high. One factor related ... more INTRODUCTION In patients with severe burns, morbidity and mortality are high. One factor related to poor prognosis is acute kidney injury. According to the AKIN criteria, acute kidney injury has 3 stages based on urine output, serum creatinine level, and renal replacement therapy. In this study, we aimed to create a decision tree for estimating risk of acute kidney injury in patients with severe burn injuries. METHODS We retrospectively evaluated 437 adult patients with ≥20% total burn surface area injury who were treated at the Baskent University Ankara and Konya Burn Centers from January 2000 to March 2020. Patients who had high-voltage burn and previous history of kidney disease were excluded. Patient demographics, medical history, mechanism of injury, presence of inhalation injury, depth of burn, laboratory values, presence of oliguria, need for renal replacement therapy, central venous pressure, and prognosis were evaluated. These data were used in a "decision tree method" to create the Baskent University model to estimate risk of acute kidney injury in severe burn patients. RESULTS Our model provided an accuracy of 71.09% for risk estimation. Of 172 patients, 78 (45%) had different degrees of acute kidney injury, with 26 of these (15.1%) receiving renal replacement therapy. Our model showed that total burn surface area was the most important factor for estimation of acute kidney injury occurrence. Other important factors included serum creatinine value, burn injury severity score, hemoglobin value, neutrophil-to-lymphocyte ratio, and platelet count. CONCLUSION The Baskent University model for acute kidney injury may be helpful to determine risk of acute kidney injury in burn patients. This determination would allow appropriate treatment to be given to high-risk patients in the early period, reducing the incidence of acute kidney injury.

Research paper thumbnail of Viral Infections In Pediatric Renal Transplant Recipients

Pediatric Transplantation, 2013

Research paper thumbnail of Primary Focal Segmental Glomerulosclerosis Recurrence After Pediatric Renal Transplantation

Experimental and Clinical Transplantation, Mar 1, 2022

OBJECTIVES Focal segmental glomerulosclerosis recurrence after renal transplant occurs frequently... more OBJECTIVES Focal segmental glomerulosclerosis recurrence after renal transplant occurs frequently in pediatric patients and is associated with poor graft survival when patients reach adulthood. We investigated recurrence rates, recurrence risk factors, management strategies, and long-term graft function among pediatric renal transplant recipients with focal segmental glomerulosclerosis as primary disease. MATERIALS AND METHODS We retrospectively evaluated medical records of 34 pediatric patients with primary focal segmental glomerulosclerosis who had undergone renal transplant between 2004 and 2019 at our center. Focal segmental glomerulosclerosis recurrence was diagnosed by the presence of nephrotic range proteinuria after transplant and confirmed by graft biopsy. Preoperative prophylactic plasma exchange was administered to pediatric renal transplant recipients with primary focal segmental glomerulosclerosis. Plasma exchange was also used to treat focal segmental glomerulosclerosis recurrence, with rituximab added if the patient did not respond to plasma exchange. RESULTS All patients (male-to-female ratio of 19:15) in our group underwent renal transplant. Mean patient age at the time of transplant was 12.72 ± 5.46 years. Twenty-nine patients received living- related donor allografts (85.3%) and 5 received organs from deceased donors (14.7%). We identified focal segmental glomerulosclerosis recurrence in 5 recipients (14.7%). Time from focal segmental glomerulosclerosis diagnosis to end-stage renal disease and duration of dialysis were shorter in the recurrence group than in the nonrecurrence group (48.4 months [range, 2-90 mo] vs 65.1 months [range, 8-123 mo] and 1.41 ± 0.82 vs 3.18 ± 1.88 years, respectively; P < .05). Donor type and transplant age were similar in both groups. Of those with recurrence who had received plasma exchange and rituximab, 3 patients (75%) had complete remission and 1 patient (25%) had partial remission. CONCLUSIONS Prophylactic plasma exchange and the combined plasma exchange-rituximab regimen for treatment of focal segmental glomerulosclerosis recurrence resulted in low recurrence and good remission rates in our pediatric cohort.

Research paper thumbnail of The effect of the use of the Gail model on breast cancer diagnosis in BIRADs 4a cases

Turkish journal of surgery, Dec 1, 2021

Objective: The BI-RADS classification system and the Gail Model are the scoring systems that cont... more Objective: The BI-RADS classification system and the Gail Model are the scoring systems that contribute to the diagnosis of breast cancer. The aim of the study was to determine the contribution of Gail Model to the diagnosis of breast lesions that were radiologically categorized as BI-RADS 4A. Material and Methods: We retrospectively examined the medical records of 320 patients between January 2011 and December 2020 whose lesions had been categorized as BI-RADS 4A. Radiological parameters of breast lesions and clinical parameters according to the Gail Model were collected. The relationship between malignant BI-RADS 4A lesions and radiological and clinical parameters was evaluated. In addition, the effect of the Gail Model on diagnosis in malignant BI-RADS 4A lesions was evaluated. results: Among radiological features, there were significant differences between lesion size, contour, microcalcification content, echogenicity, and presence of ectasia with respect to the pathological diagnosis (p< 0.05). No significant difference was found between the lesions' pathological diagnosis and the patients' Gail score (p> 0.05). An analysis of the features of the Gail model revealed that there was no significant difference between the age of menarche, age at first live birth, presence of a first-degree relative with breast cancer, and a history of breast biopsy and the pathological diagnosis (p> 0.05). Conclusion: As a conclusion Gail Model does not contribute to the diagnosis of BC, especially in patients with BI-RADS 4A lesions.

Research paper thumbnail of Gastrointestinal system perforations after pediatric liver transplantation

Turkish Journal of Surgery, 2012

ABSTRACT

Research paper thumbnail of Acute Renal Injury in Liver Transplant Patients and Its Effect on Patient Survival

Acute renal injury is a common complication in liver transplant patients. Acute kidney injury is ... more Acute renal injury is a common complication in liver transplant patients. Acute kidney injury is due to nephrotoxic drugs used after liver transplant, infections, and hemorrhage. Though it is generally reversible, it has effects on grafts and patients survival. In this retrospective observational study carried out at a single center, the effects of acute renal disease on liver recipient's survival were investigated. Liver transplant recipients of live-donor and deceased-donor transplants between January 2002 and May 2013 were included in this study; there were 310 liver transplant patients (mean age, 28 y; age range, 6 mo-62 y; 165 males, 145 females). The acute kidney disease diagnosis and staging was based on the nephrology department evaluation and daily serum creatinine levels. Patients with acute kidney injury before undergoing liver transplant and those undergoing a transplant for the second time were excluded. Kidney functions were evaluated by the nephrology department 1...

Research paper thumbnail of Early Proteinuria After Renal Transplantation and Allograft Outcomes

Transplantation Proceedings, 2014

Proteinuria is among the major and nonspecific sign of the renal disease. It is well known that l... more Proteinuria is among the major and nonspecific sign of the renal disease. It is well known that late-onset proteinuria after renal transplantation has been associated with poor allograft outcomes and with mortality. Knowledge about the impact of early proteinuria on the various outcomes is limited. We have evaluated the utility of measuring early proteinuria in the management of pediatric renal transplant recipients. We analyzed the effect of proteinuria at 3 months of posttransplantation on allograft rejection, graft loss, and estimated glomerular filtration rate (GFR) at 3 years. Proteinuria was assessed using 24-hour urine protein excretion. Renal biopsy was performed when elevated creatinine levels were elevated during routine follow-up and an acute rejection episode was proven with biopsy. Sixty-seven pediatric renal transplant recipients were included to the study. Mean follow-up time after transplantation was 48.8 ± 12.1 months. Thirty-nine recipients (58%) have proteinuria &gt;500 mg/d. The relationship could not be shown between proteinuria at posttransplant month 3 and other outcomes parameters, such as graft loss and lower estimated GFR. A significant positive correlation between acute rejection and the proteinuria at posttransplant month 3 was shown. We demonstrated that early proteinuria is a common finding in children after transplantation. Posttransplant early proteinuria cannot be used as a long-term prognostic marker of poor renal outcome. However, early proteinuria is associated with an high risk of acute rejection episodes. This would permit an opportunity for early intervention.

Research paper thumbnail of De Novo Thrombotic Microangiopathy in Renal Transplant Patients

Experimental and Clinical Transplantation, 2018

Thrombotic microangiopathy is a form of renal capillary injury possibly associated with calcineur... more Thrombotic microangiopathy is a form of renal capillary injury possibly associated with calcineurin inhibitor toxicity, acute humoral rejection, infections, and recurrent diseases. Here, we examined its incidence in patients diagnosed with acute and chronic active humoral rejection, polyomavirus nephropathy, acute cellular rejection, and immunoglobulin A recurrence. In total, 272 renal allograft recipients who met the inclusion criteria were reevaluated for presence of renal thrombotic microangiopathy. Thrombotic microangiopathy diagnosis was established by clinical, laboratory, and histologic features. C4d expression in peritubular capillaries was determined. Clinical data were collected from medical records. Of 272 patients (mean age of 42.8 ± 12.7 years), only 74 patients (27.2%) had de novo thrombotic microangiopathy, which was found in 30/90 patients (33.3%) with acute humoral rejection, 9/51 (17.6%) with acute cellular rejection, 22/53 (41.5%) with chronic active humoral rejec...

Research paper thumbnail of Hepatitis B- and hepatitis D-virus-related liver transplant: single-center data

Experimental and Clinical Transplantation, 2015

Hepatitis B and D virus coinfection or superinfection lead to chronic liver disease and have poor... more Hepatitis B and D virus coinfection or superinfection lead to chronic liver disease and have poor treatment results and poor prognosis. After transplant, these patients have difficult problems. We aimed to report long-term data of liver transplant recipients who had hepatitis B and D virus-related chronic liver disease. This retrospective, longitudinal study included 25 consecutive hepatitis B surface antigen-positive patients with antihepatitis D virus antibodies. Patient data (age, sex, antiviral treatment, posttransplant use of hepatitis B hyperimmunoglobulin and/or nucleoside/nucleotide analogues, the presence of hepatocellular carcinoma, age at transplant, follow-up) were extracted from patient records. Females comprised 32% patients. The median age was 44 years (range, 23-63 y). The serum Hepatitis B envelope antigen level was negative in all patients. At the time of transplant, 4 patients were positive for hepatitis B virus DNA and 11 patients also had hepatocellular carcinom...

Research paper thumbnail of Surgical therapy of medullary thyroid cancer and our clinical experiences

Annals of Medical Research

Aim: Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor that originates from the thyro... more Aim: Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor that originates from the thyroid parafollicular C cells and produces calcitonin. It is a quite aggressive disease with a potential to cause serious morbidity and mortality. In this study we aimed to report treatment outcomes of MTC, which has a bad prognosis and is difficult to manage. Material and Methods: The medical records of 1287 patients who were operated on for thyroid cancer between 2009 and 2018 were retrospectively assessed. Twenty-one patients (1.6%) were diagnosed with MTC. Results: Eleven (52.4%) patients were females. The age range of the patients was 54(14-85) years. Sixteen (76.2%) cases were sporadic and 5 (23.8%) were familial. Twelve patients underwent bilateral total thyroidectomy + central and unilateral neck dissection, 5(23.8%) bilateral total thyroidectomy + central and bilateral neck dissection, 4(19%) bilateral total thyroidectomy. Pathology examination revealed lymph node metastasis in 13(61.9%) patients. Three (14%) patients had simultaneous papillary thyroid cancer. Mean duration of follow-up was 52(3-96) months. Five (23.8%) patients suffered recurrence cervical lymph nodes (6 months later), lungs and bone metastasis (at 12th and 18th months), lungs (at 12thmonth), mediastinal lymph nodes (at 15th months), liver metastasis (at 6th months). Seven (33%) patients underwent chemo-radiotherapy. Conclusion: Surgery is the gold standard to control loco-regional disease and the only curative method among the available therapies in MTC treatment. Despite having a low incidence, MTC may still lead to serious mortality and morbidity in delayed cases and/or when loco-regional control cannot be achieved.

Research paper thumbnail of Results of liver transplant in elderly patients: a single center experience

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

OBJECTIVES With the increased life span, the need for liver transplant for elderly patients also ... more OBJECTIVES With the increased life span, the need for liver transplant for elderly patients also increased in the world. In this study, we reviewed our experience to determine the outcomes and problems of patients aged > 60 years who had liver transplants. MATERIALS AND METHODS Data of recipients aged > 60 years were reviewed retrospectively. We analyzed 16 elderly patients who had liver transplant for chronic liver disease between 2001 and 2014 in our center. RESULTS In our series, there were 5 women and 11 men between age 60 and 65 years. The mean Child-Pugh score was 7.9 ± 1.7 and Model for End-Stage Liver Disease score was 14.1 ± 5.1. Primary liver disease was hepatitis B in 9 patients (34.5%), most of them with hepatocellular carcinoma. The other causes of liver failure were hepatitis C (n = 4), alcoholic cirrhosis (n = 2), and cryptogenic cirrhosis (n = 2); 1 patient had both hepatitis B and hepatitis C virus, and 1 patient had both hepatitis B virus and alcoholic cirrho...

Research paper thumbnail of Does social isolation cause secondary injury in general surgery patients?

Aim: Social isolation during the pandemic has been reported to cause secondary injury to some pat... more Aim: Social isolation during the pandemic has been reported to cause secondary injury to some patient groups. The fear of secondary injury causes patients and health workers to ignore rules of social isolation. Here we aimed to evaluate secondary injury among general surgery patients during the pandemic. Methods: In this retrospective cross-sectional study, 279 patients, consulted from emergency departments to general surgery departments at Baskent University Ankara and Konya Research Centers, were analyzed. The patients were divided into two groups according to admission periods (Group 1: March 01 - May 01, 2019; n=163, Group 2: March 01 - May 01, 2020; n=116). Results: The mean age of Group 2 (50.4 (19.3)) was less than Group 1 (55.4 (20.4)). Gender (P=0.28), malignancy (P=0.53), comorbidity (P=0.27) distributions were similar. There was no significant difference in terms of admission complaints (P=0.88) and complaint durations (P=0.068). Acute cholecystitis rate was significantly...

Research paper thumbnail of Postoperative gastrointestinal bleeding after an orthotopic liver transplant: a single-center experience

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2014

OBJECTIVES The overall incidence, causes, and treatment of posttransplant gastrointestinal bleedi... more OBJECTIVES The overall incidence, causes, and treatment of posttransplant gastrointestinal bleeding, have been previously described. In this study, we examined the causes and treatment of postoperative gastrointestinal bleeding after orthotopic liver transplant. MATERIALS AND METHODS Clinical data of 335 patients who underwent an orthotopic liver transplant at our institution between September 2001 and December 2012 were analyzed retrospectively. The diagnosis and treatment of postoperative gastrointestinal bleeding after an orthotopic liver transplant were reviewed. RESULTS Gastrointestinal bleeding occurred in 13 patients (3.8%) after an orthotopic liver transplant. Five patients (38.4%) were adult and 8 patients (61.6%) were pediatric. The sites of the bleeding were Roux-en-Y anastomosis bleeding in 5 cases, peptic ulcer in 3 cases, erosive gastritis in 3 cases, gastric and esophageal varices in 1 case, and hemobilia in 1 case. These 13 patients with gastrointestinal bleeding wer...

Research paper thumbnail of Liver and kidney transplant in primary hyperoxaluria: a single center experience

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

OBJECTIVES Primary hyperoxaluria, especially type 1, is a severe disease with multisystem morbidi... more OBJECTIVES Primary hyperoxaluria, especially type 1, is a severe disease with multisystem morbidity and high mortality. We present 3 primary hyperoxaluria type 1 patients who underwent liver transplant, including living-donor liver transplant or combined liver and kidney transplant in our institution. CASE REPORTS Patients who underwent liver transplant or combined liver/kidney transplant at our institution were evaluated, retrospectively. Between January 2002 and 2013, there were 3 patients who underwent transplant for primary hyperoxaluria. All 3 patients had disease onset in childhood, and the definitive diagnosis was established at age < 1, 6, and 8 years. Although early diagnosis was made, primary hyperoxaluria resulted in end-stage renal disease in 2 patients, and hemodialysis was introduced before liver transplant. All 3 patients underwent living-donor liver transplant. Case 1 was a 10-year-old girl who had an uneventful course after living-donor liver transplant, and she ...

Research paper thumbnail of Effects of hyperuricemia on renal function in pediatric renal transplant recipients

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

OBJECTIVES Hyperuricemia is common in pediatric renal transplant recipients, and it is associated... more OBJECTIVES Hyperuricemia is common in pediatric renal transplant recipients, and it is associated with poor allograft outcomes. Hyperuricemia occurs early after transplant and is associated with use of diuretics, cyclosporine therapy, a history of hyperuricemia, and decreased glomerular filtration rate. We aimed to investigate causes and effects of hyperuricemia on allograft outcomes in our patients. MATERIALS AND METHODS There were 81 pediatric transplant patients (41 female and 40 male) included in the study. Demographic characteristics and laboratory parameters were recorded. Risk factors for hyperuricemia and the effects of plasma uric acid levels at 3, 6, 12, and 36 months on allograft outcomes were evaluated. RESULTS Mean age was 16.9 ± 5.6 years. Mean follow-up after transplant was 3.5 ± 0.47 years. Hyperuricemia was detected in 17.6% patients. A significant negative correlation was observed between 6-month uric acid level and 36-month glomerular filtration rate (r = -0.33, P...

Research paper thumbnail of Long‐term effect of eplerenone treatment in children with chronic allograft nephropathy

Pediatric Transplantation

Research paper thumbnail of Liver Transplantation Due to Fulminant Hepatic Failure

Transplantation Proceedings, 2012

Objectives. To analyze the epidemiology, causes, complications, and mortality of liver transplant... more Objectives. To analyze the epidemiology, causes, complications, and mortality of liver transplants following fulminant hepatic failure over the last 16 years. Materials and methods. We completed a descriptive analysis of 21 patients with fulminant hepatic failure and a liver transplant. In almost half of the cases, the origin of liver failure was unknown. Results. The mean age was 36 years; the study group was 47.61% female (n ϭ 10) and 52.39% male (n ϭ 11). The most common early complication was transplant rejection, which occurred in 33.3% of all patients (n ϭ 7) and was confirmed by liver biopsy; the most frequent long-term complication was autoimmune hepatitis. Two retransplantations were necessary. The total mortality rate was 38.1% (n ϭ 8) with late mortality in three patients (14.3%). Conclusions. Orthotopic liver transplantation as a treatment for fulminant hepatitis has a higher mortality rate than orthotopic liver transplantation due to other causes. It does, however, enable the survival of 62% of the patients who otherwise would have died due to liver failure. The etiology of most of the cases was unknown. We should point out the high incidence rates for transplant rejection and late autoimmune hepatitis, in addition to the possibility of hemorrhagic colonic diseases that may be associated with the condition causing liver failure. Multidisciplinary control over the patient is useful for deciding at which time a liver transplant would become the only treatment option.

Research paper thumbnail of Comparison of use of central venous catheter and arteriovenous fistula as initial vascular access in 735 patıents with end-stage renal disease

Turkish Journal of Clinics and Laboratory

Aim: Although arteriovenous fistula (AVF) has been shown as the first choice for hemodialysis (HD... more Aim: Although arteriovenous fistula (AVF) has been shown as the first choice for hemodialysis (HD), its superiority over central venous catheter (CVC) is still controversial considering the risk factors. Aim was to compare AVF and CVC, which should be is used as the first vascular access in HD. Material and Methods: Patients were divided into two groups according to the use of AVF and CVC. The groups were compared in terms of age, gender, body mass index (BMI), comorbidities, use of antiplatelet and anticoagulant agents, HD sessions per week, end stage renal disease (ESRD) duration, HD treatment duration, patency of vascular acces and number of changes. Results: When patients were grouped, 499 patients were in the CVC group and 235 patients were in the AVF group. The mean age of patients in the AVF group was higher than that of the CVC group (p=0.010). The difference between the median ESRD duration of the patients in the CVC and AVF groups was statistically significant (5 vs 6 mont...

Research paper thumbnail of COVID-19 Infections in Pediatric Renal Transplant Recipients

Experimental and Clinical Transplantation

OBJECTIVES The new coronavirus SARS-CoV-2 (COVID-19) first appeared in Turkey in March 2020, spre... more OBJECTIVES The new coronavirus SARS-CoV-2 (COVID-19) first appeared in Turkey in March 2020, spread rapidly, and caused many deaths. Although COVID-19 is mostly a respiratory disease, it can cause kidney and multiorgan failure in some cases. We believe that by sharing information about the course and effects of COVID-19 infection in kidney transplant recipients receiving long-term immunosuppressive therapy our understanding will improve. MATERIALS AND METHODS Between March 2020 and October 2021, COVID-19 was researched in kidney transplant recipients under the age of 20 years who were followed at the Başkent University Transplantation Center. We documented the clinical characteristics and prognosis of pediatric kidney transplant recipients with COVID-19 disease. RESULTS Our study group included 23 patients with COVID-19 infection from 215 pediatric kidney transplant recipients. The mean age of the patients was 14.6 ± 4.7 years; there were 9 female patients. The mean follow-up time posttransplant was 62.3 ± 43.2 months. In 13 patients (56.5%), fever was the most frequent symptom. Most patients (n = 18, 78%) had minor symptoms and recovered completely after receiving supportive treatment. Four patients (17%) required hospitalization. One was diagnosed with COVID-19 infection 1 week after being treated with rituximab for acute antibody-mediated rejection. That patient died because of significant lung disease and multiorgan failure. CONCLUSIONS Despite the fact that most of our pediatric transplant recipients had mild symptoms of COVID-19, we believe that particular caution should be observed in patients who have recently received intensive immunosuppressive medications. As a result of potential new vaccines, national immunization programs, and the emergence of novel virus strains, the clinical picture may change in the future. We believe that, as information sharing increases, we will learn more about COVID-19 in renal transplant recipients.

Research paper thumbnail of Cytomegalovirus Viremia in Solid-Organ Transplant Patients in the First Year After Transplantation

Experimental and Clinical Transplantation, Mar 1, 2022

OBJECTIVES Cytomegalovirus infection is an important problem for transplantation. Although effect... more OBJECTIVES Cytomegalovirus infection is an important problem for transplantation. Although effective antivirals for prophylaxis or preemptive therapy have reduced the severity and consequences of infection, cytomegalovirus viremia and cytomegalovirusrelated disease are still matters for patients and for graft survival. The aim of our study was to determine the frequency of cytomegalovirus infections during the first year after transplant. MATERIALS AND METHODS In this study, we analyzed the data of 252 liver and kidney transplant patients who had procedures between May 2016 and May 2020. Demographic and laboratory data of patients were recorded retrospectively and analyzed with the SPSS version 25 statistical program. RESULTS Our study included 35 liver (14%) and 217 kidney transplant recipients. The ratio of male to female was 3.8, and the median age was 41 years (range, 18-71 years). In our study group, there were 32 patients (12.7%) with cytomegalovirus DNAemia, 13 patients (5%) with cytomegalovirus syndrome, and 6 patients (2.4%) with cytomegalovirus endorgan diseases. Four patients were diagnosed with gastrointestinal disease with histopathology, and 2 patients were diagnosed with cytomegalovirus pneumonia with bronchoscopy and radiology. The mortality rate was 0.8% in the first year. CONCLUSIONS Cytomegalovirus reactivations in the first year after transplant play a critical role on graft survival in solid-organ transplant. Regular follow-up of cytomegalovirus DNAemia is crucial for modifying prophylactic and preemptive antiviral regimens.

Research paper thumbnail of A model for acute kidney injury in severe burn patients

Burns, 2022

INTRODUCTION In patients with severe burns, morbidity and mortality are high. One factor related ... more INTRODUCTION In patients with severe burns, morbidity and mortality are high. One factor related to poor prognosis is acute kidney injury. According to the AKIN criteria, acute kidney injury has 3 stages based on urine output, serum creatinine level, and renal replacement therapy. In this study, we aimed to create a decision tree for estimating risk of acute kidney injury in patients with severe burn injuries. METHODS We retrospectively evaluated 437 adult patients with ≥20% total burn surface area injury who were treated at the Baskent University Ankara and Konya Burn Centers from January 2000 to March 2020. Patients who had high-voltage burn and previous history of kidney disease were excluded. Patient demographics, medical history, mechanism of injury, presence of inhalation injury, depth of burn, laboratory values, presence of oliguria, need for renal replacement therapy, central venous pressure, and prognosis were evaluated. These data were used in a "decision tree method" to create the Baskent University model to estimate risk of acute kidney injury in severe burn patients. RESULTS Our model provided an accuracy of 71.09% for risk estimation. Of 172 patients, 78 (45%) had different degrees of acute kidney injury, with 26 of these (15.1%) receiving renal replacement therapy. Our model showed that total burn surface area was the most important factor for estimation of acute kidney injury occurrence. Other important factors included serum creatinine value, burn injury severity score, hemoglobin value, neutrophil-to-lymphocyte ratio, and platelet count. CONCLUSION The Baskent University model for acute kidney injury may be helpful to determine risk of acute kidney injury in burn patients. This determination would allow appropriate treatment to be given to high-risk patients in the early period, reducing the incidence of acute kidney injury.

Research paper thumbnail of Viral Infections In Pediatric Renal Transplant Recipients

Pediatric Transplantation, 2013

Research paper thumbnail of Primary Focal Segmental Glomerulosclerosis Recurrence After Pediatric Renal Transplantation

Experimental and Clinical Transplantation, Mar 1, 2022

OBJECTIVES Focal segmental glomerulosclerosis recurrence after renal transplant occurs frequently... more OBJECTIVES Focal segmental glomerulosclerosis recurrence after renal transplant occurs frequently in pediatric patients and is associated with poor graft survival when patients reach adulthood. We investigated recurrence rates, recurrence risk factors, management strategies, and long-term graft function among pediatric renal transplant recipients with focal segmental glomerulosclerosis as primary disease. MATERIALS AND METHODS We retrospectively evaluated medical records of 34 pediatric patients with primary focal segmental glomerulosclerosis who had undergone renal transplant between 2004 and 2019 at our center. Focal segmental glomerulosclerosis recurrence was diagnosed by the presence of nephrotic range proteinuria after transplant and confirmed by graft biopsy. Preoperative prophylactic plasma exchange was administered to pediatric renal transplant recipients with primary focal segmental glomerulosclerosis. Plasma exchange was also used to treat focal segmental glomerulosclerosis recurrence, with rituximab added if the patient did not respond to plasma exchange. RESULTS All patients (male-to-female ratio of 19:15) in our group underwent renal transplant. Mean patient age at the time of transplant was 12.72 ± 5.46 years. Twenty-nine patients received living- related donor allografts (85.3%) and 5 received organs from deceased donors (14.7%). We identified focal segmental glomerulosclerosis recurrence in 5 recipients (14.7%). Time from focal segmental glomerulosclerosis diagnosis to end-stage renal disease and duration of dialysis were shorter in the recurrence group than in the nonrecurrence group (48.4 months [range, 2-90 mo] vs 65.1 months [range, 8-123 mo] and 1.41 ± 0.82 vs 3.18 ± 1.88 years, respectively; P < .05). Donor type and transplant age were similar in both groups. Of those with recurrence who had received plasma exchange and rituximab, 3 patients (75%) had complete remission and 1 patient (25%) had partial remission. CONCLUSIONS Prophylactic plasma exchange and the combined plasma exchange-rituximab regimen for treatment of focal segmental glomerulosclerosis recurrence resulted in low recurrence and good remission rates in our pediatric cohort.

Research paper thumbnail of The effect of the use of the Gail model on breast cancer diagnosis in BIRADs 4a cases

Turkish journal of surgery, Dec 1, 2021

Objective: The BI-RADS classification system and the Gail Model are the scoring systems that cont... more Objective: The BI-RADS classification system and the Gail Model are the scoring systems that contribute to the diagnosis of breast cancer. The aim of the study was to determine the contribution of Gail Model to the diagnosis of breast lesions that were radiologically categorized as BI-RADS 4A. Material and Methods: We retrospectively examined the medical records of 320 patients between January 2011 and December 2020 whose lesions had been categorized as BI-RADS 4A. Radiological parameters of breast lesions and clinical parameters according to the Gail Model were collected. The relationship between malignant BI-RADS 4A lesions and radiological and clinical parameters was evaluated. In addition, the effect of the Gail Model on diagnosis in malignant BI-RADS 4A lesions was evaluated. results: Among radiological features, there were significant differences between lesion size, contour, microcalcification content, echogenicity, and presence of ectasia with respect to the pathological diagnosis (p< 0.05). No significant difference was found between the lesions' pathological diagnosis and the patients' Gail score (p> 0.05). An analysis of the features of the Gail model revealed that there was no significant difference between the age of menarche, age at first live birth, presence of a first-degree relative with breast cancer, and a history of breast biopsy and the pathological diagnosis (p> 0.05). Conclusion: As a conclusion Gail Model does not contribute to the diagnosis of BC, especially in patients with BI-RADS 4A lesions.

Research paper thumbnail of Gastrointestinal system perforations after pediatric liver transplantation

Turkish Journal of Surgery, 2012

ABSTRACT

Research paper thumbnail of Acute Renal Injury in Liver Transplant Patients and Its Effect on Patient Survival

Acute renal injury is a common complication in liver transplant patients. Acute kidney injury is ... more Acute renal injury is a common complication in liver transplant patients. Acute kidney injury is due to nephrotoxic drugs used after liver transplant, infections, and hemorrhage. Though it is generally reversible, it has effects on grafts and patients survival. In this retrospective observational study carried out at a single center, the effects of acute renal disease on liver recipient's survival were investigated. Liver transplant recipients of live-donor and deceased-donor transplants between January 2002 and May 2013 were included in this study; there were 310 liver transplant patients (mean age, 28 y; age range, 6 mo-62 y; 165 males, 145 females). The acute kidney disease diagnosis and staging was based on the nephrology department evaluation and daily serum creatinine levels. Patients with acute kidney injury before undergoing liver transplant and those undergoing a transplant for the second time were excluded. Kidney functions were evaluated by the nephrology department 1...

Research paper thumbnail of Early Proteinuria After Renal Transplantation and Allograft Outcomes

Transplantation Proceedings, 2014

Proteinuria is among the major and nonspecific sign of the renal disease. It is well known that l... more Proteinuria is among the major and nonspecific sign of the renal disease. It is well known that late-onset proteinuria after renal transplantation has been associated with poor allograft outcomes and with mortality. Knowledge about the impact of early proteinuria on the various outcomes is limited. We have evaluated the utility of measuring early proteinuria in the management of pediatric renal transplant recipients. We analyzed the effect of proteinuria at 3 months of posttransplantation on allograft rejection, graft loss, and estimated glomerular filtration rate (GFR) at 3 years. Proteinuria was assessed using 24-hour urine protein excretion. Renal biopsy was performed when elevated creatinine levels were elevated during routine follow-up and an acute rejection episode was proven with biopsy. Sixty-seven pediatric renal transplant recipients were included to the study. Mean follow-up time after transplantation was 48.8 ± 12.1 months. Thirty-nine recipients (58%) have proteinuria &gt;500 mg/d. The relationship could not be shown between proteinuria at posttransplant month 3 and other outcomes parameters, such as graft loss and lower estimated GFR. A significant positive correlation between acute rejection and the proteinuria at posttransplant month 3 was shown. We demonstrated that early proteinuria is a common finding in children after transplantation. Posttransplant early proteinuria cannot be used as a long-term prognostic marker of poor renal outcome. However, early proteinuria is associated with an high risk of acute rejection episodes. This would permit an opportunity for early intervention.

Research paper thumbnail of De Novo Thrombotic Microangiopathy in Renal Transplant Patients

Experimental and Clinical Transplantation, 2018

Thrombotic microangiopathy is a form of renal capillary injury possibly associated with calcineur... more Thrombotic microangiopathy is a form of renal capillary injury possibly associated with calcineurin inhibitor toxicity, acute humoral rejection, infections, and recurrent diseases. Here, we examined its incidence in patients diagnosed with acute and chronic active humoral rejection, polyomavirus nephropathy, acute cellular rejection, and immunoglobulin A recurrence. In total, 272 renal allograft recipients who met the inclusion criteria were reevaluated for presence of renal thrombotic microangiopathy. Thrombotic microangiopathy diagnosis was established by clinical, laboratory, and histologic features. C4d expression in peritubular capillaries was determined. Clinical data were collected from medical records. Of 272 patients (mean age of 42.8 ± 12.7 years), only 74 patients (27.2%) had de novo thrombotic microangiopathy, which was found in 30/90 patients (33.3%) with acute humoral rejection, 9/51 (17.6%) with acute cellular rejection, 22/53 (41.5%) with chronic active humoral rejec...

Research paper thumbnail of Hepatitis B- and hepatitis D-virus-related liver transplant: single-center data

Experimental and Clinical Transplantation, 2015

Hepatitis B and D virus coinfection or superinfection lead to chronic liver disease and have poor... more Hepatitis B and D virus coinfection or superinfection lead to chronic liver disease and have poor treatment results and poor prognosis. After transplant, these patients have difficult problems. We aimed to report long-term data of liver transplant recipients who had hepatitis B and D virus-related chronic liver disease. This retrospective, longitudinal study included 25 consecutive hepatitis B surface antigen-positive patients with antihepatitis D virus antibodies. Patient data (age, sex, antiviral treatment, posttransplant use of hepatitis B hyperimmunoglobulin and/or nucleoside/nucleotide analogues, the presence of hepatocellular carcinoma, age at transplant, follow-up) were extracted from patient records. Females comprised 32% patients. The median age was 44 years (range, 23-63 y). The serum Hepatitis B envelope antigen level was negative in all patients. At the time of transplant, 4 patients were positive for hepatitis B virus DNA and 11 patients also had hepatocellular carcinom...

Research paper thumbnail of Surgical therapy of medullary thyroid cancer and our clinical experiences

Annals of Medical Research

Aim: Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor that originates from the thyro... more Aim: Medullary thyroid cancer (MTC) is a rare neuroendocrine tumor that originates from the thyroid parafollicular C cells and produces calcitonin. It is a quite aggressive disease with a potential to cause serious morbidity and mortality. In this study we aimed to report treatment outcomes of MTC, which has a bad prognosis and is difficult to manage. Material and Methods: The medical records of 1287 patients who were operated on for thyroid cancer between 2009 and 2018 were retrospectively assessed. Twenty-one patients (1.6%) were diagnosed with MTC. Results: Eleven (52.4%) patients were females. The age range of the patients was 54(14-85) years. Sixteen (76.2%) cases were sporadic and 5 (23.8%) were familial. Twelve patients underwent bilateral total thyroidectomy + central and unilateral neck dissection, 5(23.8%) bilateral total thyroidectomy + central and bilateral neck dissection, 4(19%) bilateral total thyroidectomy. Pathology examination revealed lymph node metastasis in 13(61.9%) patients. Three (14%) patients had simultaneous papillary thyroid cancer. Mean duration of follow-up was 52(3-96) months. Five (23.8%) patients suffered recurrence cervical lymph nodes (6 months later), lungs and bone metastasis (at 12th and 18th months), lungs (at 12thmonth), mediastinal lymph nodes (at 15th months), liver metastasis (at 6th months). Seven (33%) patients underwent chemo-radiotherapy. Conclusion: Surgery is the gold standard to control loco-regional disease and the only curative method among the available therapies in MTC treatment. Despite having a low incidence, MTC may still lead to serious mortality and morbidity in delayed cases and/or when loco-regional control cannot be achieved.

Research paper thumbnail of Results of liver transplant in elderly patients: a single center experience

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

OBJECTIVES With the increased life span, the need for liver transplant for elderly patients also ... more OBJECTIVES With the increased life span, the need for liver transplant for elderly patients also increased in the world. In this study, we reviewed our experience to determine the outcomes and problems of patients aged > 60 years who had liver transplants. MATERIALS AND METHODS Data of recipients aged > 60 years were reviewed retrospectively. We analyzed 16 elderly patients who had liver transplant for chronic liver disease between 2001 and 2014 in our center. RESULTS In our series, there were 5 women and 11 men between age 60 and 65 years. The mean Child-Pugh score was 7.9 ± 1.7 and Model for End-Stage Liver Disease score was 14.1 ± 5.1. Primary liver disease was hepatitis B in 9 patients (34.5%), most of them with hepatocellular carcinoma. The other causes of liver failure were hepatitis C (n = 4), alcoholic cirrhosis (n = 2), and cryptogenic cirrhosis (n = 2); 1 patient had both hepatitis B and hepatitis C virus, and 1 patient had both hepatitis B virus and alcoholic cirrho...

Research paper thumbnail of Does social isolation cause secondary injury in general surgery patients?

Aim: Social isolation during the pandemic has been reported to cause secondary injury to some pat... more Aim: Social isolation during the pandemic has been reported to cause secondary injury to some patient groups. The fear of secondary injury causes patients and health workers to ignore rules of social isolation. Here we aimed to evaluate secondary injury among general surgery patients during the pandemic. Methods: In this retrospective cross-sectional study, 279 patients, consulted from emergency departments to general surgery departments at Baskent University Ankara and Konya Research Centers, were analyzed. The patients were divided into two groups according to admission periods (Group 1: March 01 - May 01, 2019; n=163, Group 2: March 01 - May 01, 2020; n=116). Results: The mean age of Group 2 (50.4 (19.3)) was less than Group 1 (55.4 (20.4)). Gender (P=0.28), malignancy (P=0.53), comorbidity (P=0.27) distributions were similar. There was no significant difference in terms of admission complaints (P=0.88) and complaint durations (P=0.068). Acute cholecystitis rate was significantly...

Research paper thumbnail of Postoperative gastrointestinal bleeding after an orthotopic liver transplant: a single-center experience

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2014

OBJECTIVES The overall incidence, causes, and treatment of posttransplant gastrointestinal bleedi... more OBJECTIVES The overall incidence, causes, and treatment of posttransplant gastrointestinal bleeding, have been previously described. In this study, we examined the causes and treatment of postoperative gastrointestinal bleeding after orthotopic liver transplant. MATERIALS AND METHODS Clinical data of 335 patients who underwent an orthotopic liver transplant at our institution between September 2001 and December 2012 were analyzed retrospectively. The diagnosis and treatment of postoperative gastrointestinal bleeding after an orthotopic liver transplant were reviewed. RESULTS Gastrointestinal bleeding occurred in 13 patients (3.8%) after an orthotopic liver transplant. Five patients (38.4%) were adult and 8 patients (61.6%) were pediatric. The sites of the bleeding were Roux-en-Y anastomosis bleeding in 5 cases, peptic ulcer in 3 cases, erosive gastritis in 3 cases, gastric and esophageal varices in 1 case, and hemobilia in 1 case. These 13 patients with gastrointestinal bleeding wer...

Research paper thumbnail of Liver and kidney transplant in primary hyperoxaluria: a single center experience

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

OBJECTIVES Primary hyperoxaluria, especially type 1, is a severe disease with multisystem morbidi... more OBJECTIVES Primary hyperoxaluria, especially type 1, is a severe disease with multisystem morbidity and high mortality. We present 3 primary hyperoxaluria type 1 patients who underwent liver transplant, including living-donor liver transplant or combined liver and kidney transplant in our institution. CASE REPORTS Patients who underwent liver transplant or combined liver/kidney transplant at our institution were evaluated, retrospectively. Between January 2002 and 2013, there were 3 patients who underwent transplant for primary hyperoxaluria. All 3 patients had disease onset in childhood, and the definitive diagnosis was established at age < 1, 6, and 8 years. Although early diagnosis was made, primary hyperoxaluria resulted in end-stage renal disease in 2 patients, and hemodialysis was introduced before liver transplant. All 3 patients underwent living-donor liver transplant. Case 1 was a 10-year-old girl who had an uneventful course after living-donor liver transplant, and she ...

Research paper thumbnail of Effects of hyperuricemia on renal function in pediatric renal transplant recipients

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

OBJECTIVES Hyperuricemia is common in pediatric renal transplant recipients, and it is associated... more OBJECTIVES Hyperuricemia is common in pediatric renal transplant recipients, and it is associated with poor allograft outcomes. Hyperuricemia occurs early after transplant and is associated with use of diuretics, cyclosporine therapy, a history of hyperuricemia, and decreased glomerular filtration rate. We aimed to investigate causes and effects of hyperuricemia on allograft outcomes in our patients. MATERIALS AND METHODS There were 81 pediatric transplant patients (41 female and 40 male) included in the study. Demographic characteristics and laboratory parameters were recorded. Risk factors for hyperuricemia and the effects of plasma uric acid levels at 3, 6, 12, and 36 months on allograft outcomes were evaluated. RESULTS Mean age was 16.9 ± 5.6 years. Mean follow-up after transplant was 3.5 ± 0.47 years. Hyperuricemia was detected in 17.6% patients. A significant negative correlation was observed between 6-month uric acid level and 36-month glomerular filtration rate (r = -0.33, P...