BNT162b2 or CoronaVac as the Third Dose against Omicron: Neutralizing Antibody Responses among Transplant Recipients Who Had Received Two Doses of CoronaVac.

We evaluated neutralizing antibodies against the Omicron variant and Anti-Spike IgG response in solid organ (SOT) or hematopoietic stem cell (HSTC) recipients after a third dose of BNT162b2 (BNT) or CoronaVac (CV) following two doses of CV. In total, 95 participants underwent SOT (n = 62; 44 liver, 18 kidney) or HSCT (n = 27; 5 allogeneic, 22 autologous) were included from five centers in Turkey. The median time between third doses and serum sampling was 154 days (range between 15 to 381). The vaccine-induced antibody responses of both neutralizing antibodies and Anti-Spike IgGs were assessed by plaque neutralizing assay and immunoassay, respectively. Neutralizing antibody and Anti-Spike IgG levels were significantly higher in transplant patients receiving BNT compared to those receiving CV (Geometric mean (GMT):26.76 vs. 10.89; p = 0.03 and 2116 Au/mL vs. 172.1 Au/mL; p < 0.001). Solid organ transplantation recipients, particularly liver transplant recipients, showed lower antibody levels than HSCT recipients. Thus, among HSCT recipients, the GMT after BNT was 91.29 and it was 15.81 in the SOT group (p < 0.001). In SOT, antibody levels after BNT in kidney transplantation recipients were significantly higher than those in liver transplantation recipients (GMT: 48.32 vs. 11.72) (p < 0.001). Moreover, the neutralizing antibody levels after CV were very low (GMT: 10.81) in kidney transplantation recipients and below the detection limit (<10) in liver transplant recipients. This study highlights the superiority of BNT responses against Omicron as a third dose among transplant recipients after two doses of CV. The lack of neutralizing antibodies against Omicron after CV in liver transplant recipients should be taken into consideration, particularly in countries where inactivated vaccines are available in addition to mRNA vaccines.

Choroidal Vascularity Index and Choroidal Thickness Changes Following Renal Transplantation.

Objectives: This study aimed to evaluate changes in subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), estimated glomerular filtration rate (GFR), mean arterial pressure (MAP), and intraocular pressure (IOP) after renal transplantation. Materials and Methods: A total of 49 renal transplantation patients were included in this prospective study. CVI and SFCT on enhanced-depth imaging optic coherence tomography (EDI-OCT), MAP at the cubital fossa, GFR, and IOP were measured preoperatively and at postoperative 1 week and 1 month. In the analysis of EDI-OCT images, luminal area (LA) and stromal area of the choroid were determined using the image binarization method. CVI was defined as the ratio of LA to total choroid area. The effects of GFR, IOP, and MAP on CVI and SFCT were investigated. Results: The study included 23 women (47%) and 26 men (53%) with a mean age of 26.28±8.25 years (range: 18-52). Changes between preoperative, postoperative 1-week, and postoperative 1-month GFR values, CVI, and SFCT measurements were evaluated. There were significant differences between preoperative and postoperative GFR and SFCT measurements (p<0.001), but no significant differences between preoperative and postoperative CVI (p=0.09), MAP (p=0.14), or IOP (p=0.84) measurements. Conclusion: The present study demonstrated that SFCT increased significantly with GFR, while there was no change in CVI values.

Our Pediatric Liver and Kidney Transplant Activities in 2021.

OBJECTIVES: In children with end-stage renal disease, chronic liver failure, or acute liver failure, liver transplant and kidney transplant are the most effective modalities for better clinical outcomes compared with other therapies. However, children are particularly susceptible to surgical complications, so pediatric solid-organ transplants should be reserved for centers with substantial experience and multidisciplinary expertise. Here, we assessed liver and kidney transplants performed at our center in 2021. MATERIALS AND METHODS: From November 3, 1975, to December 31, 2021, we performed 701 liver transplants and 3290 kidney transplants. From January 1, 2021, to December 31, 2021, we performed 21 liver transplants (19 in children) and 114 kidney transplants (12 in children). We recorded age, sex, body mass index, comorbidities, etiologies, laboratory values, and clinical outcomes. RESULTS: For the year 2021, we performed 19 pediatric liver transplants and 12 pediatric kidney transplants. Mean age of liver recipients was 3.4 years, and 8 were male patients. The most common etiology was biliary atresia (n = 7). All liver grafts were from living related donors who were first-degree (n = 16) or second- degree (n = 3) relatives of the recipients. Mean hospital stay was 17.6 days. All but 2 liver transplant recipients were discharged successfully (2 died from sepsis in the early postoperative period). Mean age of kidney transplant recipients was 14.1 years, and 4 were male patients. The most common etiology was vesicoureteral reflux (n = 3). One kidney graft was from a deceased donor, with the rest from living related donors who were first-degree relatives of the recipients (n = 11; mother for 8 recipients and father for 3 recipients). Mean hospital stay was 4.3 days. All kidney transplant recipients were discharged successfully. CONCLUSIONS: Solid-organ transplants for young children are often complex but can be performed successfully at experienced transplant centers.

BK Polyomavirus Infection and Risk Factors in Pediatric Patients Undergoing Kidney Transplant.

OBJECTIVES: BK polyomavirus infection is a critical complication affecting graft survival after kidney transplant. We aimed to determine the frequency, the effect on graft function, and the risk factors of BK polyomavirus infection in pediatric kidney transplant patients. MATERIALS AND METHODS: We retrospectively reviewed data of 144 pediatric patients (female/male: 67/77; 0-18 years of age) who received kidney transplants in the past 10 years at our center. Demographic/ laboratory data, kidney failure etiologies, donor types, and immunosuppressive treatments were recorded. Patients were grouped as those with and without BKV infection, with groups compared in terms of transplant age, sex, kidney failure etiology, donor type, immunosuppressive treatments, presence of ureteral stents, acute rejection episodes, accompanying viral infections, glomerular filtration rate, and graft loss rate. RESULTS: Twelve patients (8.3%) had BK polyomavirus infection. All 12 patients had viruria (8.3%), 8 (5.5%) had viremia, and 4 (2.8%) had BK polyomavirus nephropathy. Two patients (1.4%) had graft loss because of BK polyomavirus nephropathy. When patients with and without infection were compared, no significant differences were found in terms of sex, transplant age, donor type, presence of a ureteral stent, acute rejection, graft loss, or immunosuppressive treatment (P > .05). Rates of congenital anomalies of the kidney and urinary tract were 30.3% and 66.6% in those without and with BK polyomavirus infection, respectively (P < .05). The group positive for BK polyomavirus had a significantly higher incidence of cytomegalovirus infection versus the group without infection (P < .05). Glomerular filtration rate values at years 1 and 3 were similar between groups (P > .05). CONCLUSIONS: Frequency of BK polyomavirus nephropathy in pediatric patients undergoing kidney transplant in our center was consistent with data from other centers. Graft loss can be prevented by early detection and treatment through close periodic control and adequate evaluation of risk factors.

An Alternative Abdominal Closure Technique After Pediatric Liver Transplant: Bogota Bag Technique.

OBJECTIVES: In conditions such as large-for-size syndrome, postreperfusion hepatic edema, and intestinal edema, primary closure of the abdominal wall can cause respiratory complications and thrombosis of vascular structures. Here, we compared results of primary abdominal closure versus a temporary patch closure technique (the Bogota bag technique) in pediatric liver transplant recipients. MATERIALS AND METHODS: We performed primary abdominal closure in 295 recipients. In 39 pediatric liver transplant recipients, the Bogota bag technique was used as the abdominal closure technique because of suspected intraoperative tense abdominal closure. In patients who had the Bogota bag technique, we sutured the sterilized saline bag to the skin at the edge of the defect by shaping the defect so as not to cause abdominal hypertension. Primary abdominal closure was achieved in patients after control laparotomies at 48-hour intervals. RESULTS: The mean age of the primary abdominal closure group was 8.38 years, whereas the mean age of the Bogota bag group was 2 years. The average weight of patients in the primary abdominal closure group was 26.38 kg, and the average weight of patients in the Bogota bag group was 7.93 kg. Biliary atresia was the most common indication in both groups. Mean length of hospital stay was 21 days in the primary abdominal closure group and 24 days in Bogota bag group. Six patients in the Bogota bag group died from sepsis or bleeding in the early postoperative period. In the Bogota bag group, wound closure was achieved within 2 weeks in 25 patients and within 3 weeks in 8 patients. CONCLUSIONS: Temporary patch closure techniques can be used safely in low-weight and young children, children with large-for-size grafts, and those who display increased intra-abdominal pressure.

Vascular Complications in Pediatric Liver Transplants and Their Management.

OBJECTIVES: The blood supply of the liver occurs through the hepatic artery and portal vein. Outflow of blood circulation in the liver is via the hepatic veins. Any disruption in this blood circulation results in deterioration of liver functions. In this study, we evaluated early vascular complications in pediatric liver transplant recipients seen at our center. MATERIALS AND METHODS: From November 1988 to December 2021, our team has performed 701 liver transplant procedures, which have included 334 pediatric liver transplants. Among these pediatric liver transplant recipients (mean age of 7.34 y), 176 were male patients. Nineteen patients (5.7%) were recipients of deceased donors. Reason for liver failure was mainly biliary atresia (n = 169). Mean weight of recipients was 23.3 kg. Most graft types were left lateral grafts (n = 204). RESULTS: Three patients had hepatic vein complications. All 3 patients were successfully treated with interventional radiological methods by placing a stent in the anastomosis region. Portal vein complications occurred in 3 patients. One patient had hemostasis performed surgically. The second patient had surgically revision of the anastomosis because of thrombus formation. Because of stenosis of more than 50% in the portal vein anastomosis, the third patient required stent placement in the anastomosis region. Hepatic artery complications occurred in 54 patients: 31 patients had hepatic artery thrombosis, 13 patients had hepatic artery stenosis, 7 patients had bleeding from hepatic artery anastomosis, 2 patients had hepatic artery dissection, and 1 patient had pseudoaneurysm in the hepatic artery. Forty-three of these patients were successfully treated with interventional radiological methods and 11 required surgical treatment. CONCLUSIONS: Vascular complications after liver transplant can cause deterioration in hepatic functions and acute liver failure. Vascular complications can be successfully treated in experienced organ transplant centers.

Long-Term Follow-up of Over 600 Living Related Kidney Donors: Single-Center Experience.

OBJECTIVES: Kidney transplant is the treatment of choice in patients with end-stage renal disease because it offers improved survival and better quality of life. Although most epidemiologic studies have suggested that living kidney donors have a minimal lifetime risk of developing end-stage renal disease, long-term complications and physiologic and psychologic sequelae resulting from donation remain unclear. Here, we examined the long-term results of living-related kidney donors who donated kidneys at the Baskent University Ankara Hospital over the past 25 years. MATERIALS AND METHODS: We were able to examine 607 kidney transplant donors (mean age of 52.03 ± 11.54 years) who were seen at our center from 1986 to 2021 and who agreed to a general health evaluation. Collected data included donor age, sex, blood type, body mass index, duration after donation, blood pressure measurements, biochemical parameters, abdominal ultrasonograph for size, structure, and renal blood flow of the solitary kidney, comorbid conditions, chronic drug use, and surgical procedures after donation. RESULTS: Mean time after donation was 10.4 ± 3.2 years. Twenty-four donors (3.9%) were diagnosed with diabetes and 21 (3.4%) with thyroid disease, 64 (10.5%) developed hypertension, and 48 (8.8%) developed atherosclerotic cardiovascular disease. Obesity was found to be an increasing problem in our donor population, with 174 (28.6%) developing mild to moderate obesity (body mass index >25 kg/m2). Older age, obesity, smoking, and hyperlipidemia were found to be the major and independent risk factors of both hypertension and atherosclerotic cardiovascular disease in donors. None of our donors developed endstage renal disease. CONCLUSIONS: Obesity and hypertension were the most common comorbidities that developed in our kidney donor population. Our principle is to avoid unrelated and nondirected donors because of the possible long-term complications. Unrelated donors may be desperate if a family member needs donation in the future.

Liver Transplant Recipients Who Survive for More Than 10 Years: A Long-Term Survey.

OBJECTIVES: Liver transplant is the gold standard treatment for end-stage liver failure. Short-term and midterm surveys have been published, but there are few long-term surveys. Here, we report the outcomes of our long-term liver transplant survivors. MATERIALS AND METHODS: Since 1988, we have performed 694 liver transplants (366 adult, 328 pediatric), including the first deceased donor transplant in Turkey (December 8, 1988); the first pediatric segmental living related transplant in Turkey, the Middle and Near East, and Europe; the world's first adult segmental living related transplant (April 24, 1990); and the world's first living related donor combined liver-kidney transplant (May 16, 1992). We retrospectively evaluated data from recipients who survived >10 years with normal graft function. RESULTS: Of 215 recipients, survival ranges were ≥20 years (n = 13), 15 to 19 years (n = 86), and 10 to 14 years (n = 116); 211 remain alive today with normal liver function. There were 5 retransplants to treat chronic graft rejection, of which 4 recipients are alive with normal graft function after a second liver transplant (15, 20, 22, and 31 years after first transplant). One patient died soon after the second liver transplant (15 years after first transplant). Acute rejection episodes were seen in 72 (34%), and 7 were steroid resistant. There were 48 (22.7%) drug-induced complications. Ten patients had de novo malignancy: 5 lymphoma, 2 squamous cell carcinoma, 1 gastrointestinal stromal tumor, 1 thyroid papillary carcinoma, and 1 multiple myeloma. There were also 31 patients with hepatocellular carcinoma before liver transplant: 13 were beyond Milan criteria, 6 had incidental HCC, and 12 were within Milan. CONCLUSIONS: Long-term survival after liver transplant is possible with expert care. Few reports have mentioned long-term surveys; our long-term liver transplant survey is among the largest series in the literature.

Stereotactic Ablative Body Radiotherapy as a Bridge to Liver Transplant for Hepatocellular Carcinoma: Preliminary Results of Baskent University Experience.

OBJECTIVES: Hepatocellular carcinoma is the most common primary liver tumor, with curative treatment options being liver transplant and resection. However, approximately 20% to 30% of patients have substantial disease progression while awaiting transplant. Here, we report our initial experience on stereotactic ablative body radiotherapy as a bridge to liver transplant for patients with hepatocellular carcinoma. MATERIALS AND METHODS: Seven patients with 9 lesions received stereotactic ablative body radiotherapy as a bridge treatment to transplant. All patients underwent radiofrequency ablation, transcatheter arterial chemoembolization, or hepatic resection before stereotactic ablative body radiotherapy. Magnetic resonance imaging was used to evaluate radiographic responses 1 month later. RESULTS: Median age of patients was 65 years (range, 63-71 years), median stereotactic ablative body radiotherapy dose was 45 Gy (range, 30-54 Gy; delivered in 3-5 fractions), and median tumor diameter was 17 mm (range, 12-30 mm). Before stereotactic ablative body radiotherapy, all patients underwent liver-directed therapies, including transcatheter arterial chemoembolization for 3 lesions, transcatheter arterial chemoembolization and radiofrequency ablation for 4 lesions, surgical resection for 1 lesion, and surgical resection plus transcatheter arterial chemoembolization for the remaining lesion. Patients showed no evidence of gastrointestinal toxicity or radiation-induced liver disease. Acute toxicity was negligible; all patients completed the treatment course. One month after stereotactic ablative body radiotherapy administration, response rates were assessed with magnetic resonance imaging, with complete responses obtained in 5 lesions (55.5%), partial responses for 2 lesions, and stable disease for 2 lesions. No disease progression was shown following stereotactic ablative body radiotherapy application. CONCLUSIONS: Stereotactic ablative body radiotherapy is an effective, safe, and tolerable bridging therapy option. Although we observed an early response after treatment, exact response rates will not be known for at least 3 months following stereotactic ablative body radiotherapy. Thus, our findings should be confirmed through additional prospective studies with longer follow-up.

Effect of meal intake for evaluating hepatic artery by Doppler ultrasonography in liver transplants: Does fasting matter for screening hepatic artery due to hemodynamic changes in splanchnic circulation?

PURPOSE: The aim of this study is to assess the utility of fasting on Doppler ultrasonography findings of hepatic artery in liver transplants. METHODS: Liver transplant patients without vascular abnormalities were prospectively evaluated between December 2017 and January 2020. Doppler sonography was used to describe hemodynamic changes in response to a standard meal. The diameter, peak systolic velocity, blood flow, resistive index (RI) of the main hepatic artery and portal vein peak velocity were measured. RESULTS: The mean hepatic arterial diameter of 44 patients was higher in the fasting group (4.5 mm) than in the postprandial group (3.3 mm) (p < .05). The mean hepatic arterial blood flow decreased (from .276 to .127 L/min) and hepatic arterial RI increased (from .66 to .71) following meal ingestion (p < .05). Hepatic arterial velocity was significantly lower and portal venous velocity was higher after oral intake. CONCLUSION: Meal ingestion has an important effect on hepatic artery Doppler features in liver transplants. Therefore, Doppler ultrasound evaluation should be considered after appropriate fasting due to postprandial responses of liver transplant.

Comparison of Mortality Rates in Patients Waiting for Liver Transplant and Patients With Colorectal Metastatic Tumors.

OBJECTIVES: We aimed to identify outcomes of liver surgery in patients with hepatocellular carcinoma and colorectal cancer, which result in primary and secondary liver tumors. MATERIALS AND METHODS: Our study included 51 patients with colorectal cancer and liver metastases and 63 patients with hepatocellular carcinoma who were prepared for liver transplant due to cirrhosis who underwent hepatic resection or local ablation treatments; patients were seen between January 2011 and December 2021. RESULTS: Most patients with colorectal cancer were men (58.8%). Mean age was 65.76 ± 13.818 years (range, 27-88 y). Most patients had planned, elective surgery (86.3%). Neoadjuvant chemotherapy was administered to 58.8% of patients. The most common location of metastasis in the liver was in the right lobe (43.1%), and the most common surgery was low anterior resection (17 patients). During simultaneous liver surgery, 31 patients required metastasectomy and 7 patients required radiofrequency ablation plus metastasectomy. No deaths occurred in the early posttransplant period, and cumulative survival was 82.624 ± 7.962 months. Disease-free survival was 45.2 ± 7.495 months. Most patients with hepatocellular carcinoma were men (82.5%). Mean age was 58.73 ± 17.428 years. Hepatocellular carcinoma lesions were mostly located in both the right and left lobes (23.8%). In the hepatocellular cancer group, 60.3% had transarterial chemoembolization and 42.9% had radiofrequency ablation. The primary surgical resection was metastasectomy (17.9%) because of multiple localized lesions. Median follow-up was 22 months (range, 1-126 mo). Overall survival was 101.898 ± 7.169 months, with 10-year overall survival of 38%. Disease-free survival was 74.081 ± 8.732 months, with 1-year and 5-year disease-free survival of 90.5% and 54%. CONCLUSIONS: Better survival was shown in patients with hepatocellular carcinoma than in patients with colorectal cancer.Therefore, more aggressive treatment options, as used in hepatocellular carcinoma, including liver transplant, may be options for patients with colorectal cancer.

Treatment of Posttransplant Hepatocellular Carcinoma Recurrence.

OBJECTIVES: In patients who receive liver transplant to treat hepatocellular carcinoma, 10% to 15% posttransplant recurrence is observed. In the present study, we evaluated the long-term outcomes of patients who had received liver transplant for treatment of hepatocellular carcinoma. MATERIALS AND METHODS: Of the 683 livertransplants that we performed, 72 were in response to hepatocellular carcinoma. The physical examination and laboratory and imaging results of the patients were retrospectively analyzed and recorded. The recipients were evaluated according to the Baskent criteria and divided into 2 groups: early diagnosis and late diagnosis. RESULTS: Among 72 total patients in our study, 19 (26.3%) were pediatric recipients. Hepatocellular carcinoma recurred in 7 patients (9.7%; 5 adult, 2 pediatric). Except for one patient, all were in the late diagnosis group.The mean survivaltime of all patients was 137.45 ± 10 months.The mean survival in the early diagnosis group was longer than in the late diagnosis group. During follow-up, 11 patients died from recurrence and distant metastasis. CONCLUSIONS: In patients with hepatocellular carcinoma who received liver transplant, we found that postoperative recurrence of hepatocellular carcinoma and distant metastasis can be treated with surgery and/or with interventional radiology methods, which may improve patient survival after liver transplant.

Effect of Ozone Added to University of Wisconsin Solution on Preservation Damage in Perfused Liver.

OBJECTIVES: Ischemia is defined as the inability of the tissue to provide oxygen and other metabolites by the circulation and the removal of residual products. The University of Wisconsin solution is widely used to preserve ischemia and to preserve organs for transplant. Ozone is used in various areas of ischemia damage due to its antioxidant properties. The aim of our study was to investigate the effects of ozone added to University of Wisconsin solution on perfused liver preservation injury. MATERIALS AND METHODS: Our study included 24 Sprague Dawley rats with an average weight of 300 to 350 g. Animals were divided into 4 groups: group 1 (Ringer lactate), group 2 (Ringer lactate + ozone), group 3 (University of Wisconsin solution), and group 4 (University of Wisconsin + ozone). Solutions were perfused from the liver portal vein and aorta. After perfusion, rats were killed and liver biopsies were taken at 0, 6, and 12 hours of storage for pathological examination. For biochemical analysis, samples were collected from liver specimen storage solutions at 0, 6, and 12 hours. RESULTS: Mean alanine aminotransferase/aspartate aminotransferase levels in group 3 were 77/82 U/L at hour 0, 680/461 U/L at hour 6, and 1027/682 U/L at hour 12. In group 4, these levels were 35/31 U/L at hour 0, 415/295 U/L at hour 6, and 546/372 U/L at hour 12. CONCLUSIONS: In terms of liver function values, we observed favorable result with University of Wisconsin solution with added ozone. Therefore, we suggest that the addition of ozone to the University of Wisconsin solution may be effective in preventing liver preservation damage.

Portal Venous Flow Alterations in Hepatic Artery Thrombosis Following Liver Transplant.

OBJECTIVES: The hepatic vasculature is a unique system due to a dual supply that includes the hepatic artery and portal vein, which interact when the liver vascular supply is decreased. Hepatic artery buffer response, an intrinsic regulatory mechanism that compensates for blood supply, maintains increased hepatic artery flow and caliber in response to portal vein failure. Previous studies revealed that portal vein flow showed no alterations to establish adequate blood supply in response to hepatic artery occlusion. Here, we analyzed portal vein flow changes in patients with hepatic artery thrombosis after liver transplant. MATERIALS AND METHODS: From December 1988 to October 2017, our center performed 580 liver transplant procedures. Those diagnosed with hepatic artery thrombosis (19 females, 24 males) by Doppler ultrasonography during postoperative week 1 were analyzed. Patients received either surgery or endovascular treatment for hepatic artery thrombosis, with patency confirmed by Doppler ultrasonography. We compared portal vein flow velocity and caliber before and after treatment using Wilcoxon signed rank and Mann Whitney U tests. RESULTS: Mean patient age was 18.9 ± 21.4 years. Portal vein flow velocity pretreatment (median of 70 cm/ s) was significantly higher than posttreatment (median of 52 cm/ s) in all patients (P < .001). Median flow velocity decreased significantly after treatment when subgroups were compared, including age (adult vs child), transplant type (orthotopic transplant vs living donor), and treatment (surgery vs endovascular). However, portal vein flow velocity showed a significantly higher decrease in the surgery subgroup than in the endovascular treatment subgroup (P = .018). There was no significant relationship between portal vein calibers before and after treatment (P = .36). CONCLUSIONS: The significant decrease in portal vein flow velocity after successful treatment of hepatic artery thrombosis may represent a compensatory flow change of the portal vein in response to diminished hepatic artery flow.

A model for acute kidney injury in severe burn patients.

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.

Role of Interventional Radiology in the Management of Early Vascular Complications After Liver Transplant.

OBJECTIVES: A hepatic vascular complication after liver transplant is a critical situation, often resulting in graft failure and potentially leading to patient death. Early diagnosis and treatment of vascular complications can provide prolonged graft survival and prohibit further complications. This study presents our experiences with endovascular treatment during the first week after liver transplant. MATERIALS AND METHODS: Between January 2012 and February 2021, 240 liver transplants were performed, with 43 patients having early endovascular treatment (37 men; mean age 27 ± 2.9 years) at a single center. Early endovascular interventions were carried out 1 to 7 days (mean ± SD of 2.7 ± 0.24 days) after transplant. Patients with vascular complications were grouped by arterial, venous, and portal complications. In addition, arterial complications were subgrouped by occlusive (hepatic artery thrombosis) and nonocclusive (hepatic artery stenosis/splenic artery steal syndrome) complications. Patients had median follow-up of 47 ± 4 months. RESULTS: In the first week after liver transplant, vascular complications included splenic artery steal syndrome in 27 patients (62.7%), hepatic complications in 10 patients (23.2%) (7 with hepatic artery thrombosis, 3 with hepatic artery stenosis), hepatic venous outflow complications in 4 patients (9.3%), and portal vein complications in 2 patients (4.6%). Only 1 patient required revision surgery because of excessive arterial kinking; the remaining patients with arterial complications were successfully managed with multiple endovascular treatment attempts. Patients with splenic artery steal syndrome were treated by selective arterial embolization with coil devices. Resistivity index, peak systolic velocity of hepatic arteries, and portal vein maximal velocity significantly improved (P < .001). Patients with hepatic venous outflow and portal vein complications who had endovascular treatments and vascular structures maintained good results over follow-up. CONCLUSIONS: Early endovascular intervention is feasible and safe for hepatic vascular complications following liver transplant, with high success treatment rates with advances in interventional radiology.

Differences in Antibody Responses Between an Inactivated SARS-CoV-2 Vaccine and the BNT162b2 mRNA Vaccine in Solid-Organ Transplant Recipients.

OBJECTIVES: Vaccination against SARS-CoV-2 may reduce COVID-19 mortality and complications in solidorgan transplant recipients, and we evaluated the associated antibody responses and adverse effects in this high-risk population. MATERIALS AND METHODS: This prospective observational study (April-June 2021) included 10 liver and 38 kidney transplant recipients who received 2 vaccine doses (Sinovac, n = 31; or BioNTech, n = 17) and 56 healthy adults (Sinovac), all of whom provided 3 blood samples (prevaccination, 4 weeks after first dose, and 4-6 weeks after second dose) for quantitative tests (Abbott Quant assay forimmunoglobulin G antibodies against SARS-CoV-2 spike protein). Type I error was α = .05 in all statistical analyses (SPSS, version 25). RESULTS: We analyzed demographic data, antibody responses, and adverse events after 2 doses of SARSCoV-2 vaccine, comparedimmune responses from solidorgan transplant recipients (median age, 36.5 years) versus healthy patients (median age, 37.5 years), and observed significantly higher seropositivity in healthy versus transplant patients after Sinovac vaccination (100% vs 67.5%; P = .001). However, we observed no significant seropositive differences for Sinovac versus BioNTech second doses in transplantrecipients. Median SARS-CoV-2 immunoglobulin G level after second dose was significantly higher in BioNTech (1388.6 AU/mL) versus Sinovac patients (136.6 AU/mL) (P = .012). The seropositivity difference between the 2 vaccines was significant in participants 24 to 44 years old (P = .040). The rate of at least 1 side effect was 82.4% (n = 14) for BioNTech vaccine and 32.3% (n = 10) for Sinovac vaccine, and the difference was statistically significant.The most common side effect was arm pain (significantly higher in BioNTech group). CONCLUSIONS: Solid-organ transplant recipients demonstrated inadequate vaccine responses (higher risk of complications and mortality) versus healthy patients. Furthermore, immune responses may differ between vaccines. Therefore, additional vaccine doses and strict control measures remain crucial.

Effect of Subcutaneous Topical Ozone Therapy on Second-Degree Burn Wounds in Rats: An Experimental Study.

Burns are one of the most severe traumas, causing coagulative destruction of the skin. The use of various products that accelerate wound healing in patients with burns may affect rates of patient survival and reduce complications. We studied the effects of subcutaneous ozone injection on second-degree burn wounds in an animal model. For this study, 72 Sprague-Dawley male rats were divided randomly into the following three groups: control group, silver sulfadiazine group, and ozone group; each group was then divided randomly into two subgroups (day 7 or day 14 examination and euthanized). Superficial partial-thickness burns were created on the lower back. In the control group, subcutaneous 0.9% serum saline was injected daily into the burn area. In the silver sulfadiazine group, burns were dressed daily with silver sulfadiazine. In the ozone group, subcutaneous ozone was injected daily into the burn area. We performed tissue hydroxyproline level measurements and histopathological evaluations. When groups were compared in terms of weight change, no significant difference was found between day 7 and day 14. With regard to tissue hydroxyproline levels, the ozone group had significantly higher levels on both days 7 and 14 (P < .001). In histopathological evaluations, we determined that wound healing in the ozone group was significantly higher than in the other groups. We found that subcutaneous ozone therapy was more effective than silver sulfadiazine in the healing process of second-degree burn wounds and could be safely used in the treatment of burn wounds.

Success Rate of Grafts With Multiple Renal Vessels in 3136 Kidney Transplants.

OBJECTIVES: Multiple renal vessels are often detected in living and deceased organ donors. In the past, transplant with multiple renal vessel grafts has been a contraindication because of high vascular and urological complication rates. However, improvements in vascular reconstruction and anastomosis techniques have allowed graft function to be maintained for many years. Here, we retrospectively evaluated transplant of multiple renal vessel grafts and graft survival and postoperative vascular and urological complications. MATERIALS AND METHODS: From November 1975 to July 2020, there were 3136 renal transplants (716 deceased donors, 2420 living donors) performed in our center. There were 2167 living donors and 643 deceased donors with single renal vessel grafts and 253 living donors and 73 deceased donors with multiple renal vessel grafts. For anastomoses, external iliac, internal iliac, common iliac, and inferior epigastric arteries and external iliac veins were used. Cold ischemia time, anastomosis time, postoperative vascular and urological complications, acute tubular necrosis, creatinine clearance, serum creatinine levels, graft rejection episodes, and graft and patient survival rates were evaluated. RESULTS: With regard to creatinine clearance, cold ischemia and anastomosis time, acute tubular necrosis, rejection episodes, and 1-, 2-, and 5-year posttransplant serum creatinine levels, there were no significant differences between the groups. Graft survival rates in the single renal vessel group were 92.9% at 1 year posttransplant and 78.3% at 5 years posttransplant; rates in the multiple renal vessel group were 93.1% at 1 year and 79.7% at 5 years. The corresponding patient survival rates were 95.5% (1 year) and 92.9% (5 years) for the single renal vessel group and 96.9% (1 year) and 87.2% (5 years) for the multiple renal vessel group. CONCLUSIONS: Improved anastomosis and recon struction techniques have allowed the safe transplant of multiple renal vessel grafts that may remain functional for many years.

The New Anterior Less Invasive Crescentic Incision for Living Donor Nephrectomy.

OBJECTIVES: Living-donor nephrectomy is a devoted procedure performed in a healthy individual; for these procedures, it is essential to complete the surgery with the lowest possible risk and morbidity and allow donors to regain their normal daily activity. To minimize anatomic and physiologic damage, we modified a surgical technique. Here, we report our experiences with the new anterior less invasive crescentic donor nephrectomy technique. MATERIALS AND METHODS: We retrospectively evaluated 728 donor nephrectomy patients who had the new anterior less invasive cresentic incision (n = 224), the classic open (n = 431), or the laparoscopic living-donor nephrectomy (n = 73) procedures. Demographic characteristics, preoperative and postoperative parameters, acute renal graft dysfunction, and firstyear graft and patient survival rates were compared between groups. RESULTS: During the operation, the new cresentic incision living-donor nephrectomy allowed a safe and comfortable position for the patient and the anesthesiologist. Also, it procures safe access especially for grefts with multiple vessels. Patients had lower pain scores (P = .010), shorter hospital stays (2.25 vs 3.49 days) than those who received the classic open living-donor nephrectomy. Patients who received laparoscopic living-donor nephrectomy had significantly longer mean operation time (P = .016) and warm ischemia time (P ≤ .001) than those who had the new cresentic incision technique. All groups showed similar rates of first-year survival and delayed graft dysfunction. CONCLUSIONS: The new anterior less invasive cresentic incision open-donor nephrectomy approach is a safe, comfortable, effective, and less invasive modification of the living donor nephrectomy. Also, it procures safe access for grefts with multiple vessels.