Suspected Simple Appendicitis in Children: Should We Use a Nonoperative, Antibiotic-Free Approach? An Observational Study.

BACKGROUND: Simple appendicitis may be self-limiting or require antibiotic treatment or appendectomy. The aim of this study was to assess the feasibility and safety of a nonoperative, antibiotic-free approach for suspected simple appendicitis in children. METHODS: This single-center, retrospective study included patients (0-17 years old) who were hospitalized at the pediatric surgery department due to suspected appendicitis between 2011 and 2012. Data from patients who primarily underwent appendectomy were used as controls. The follow-up of nonoperatively managed patients was conducted in 2014. The main outcome of interest was appendicitis recurrence. RESULTS: A total of 365 patients were included: 226 were treated conservatively and 139 underwent appendectomy. Fourteen (6.2% of 226) of the primarily nonoperatively treated patients required secondary appendectomy during follow-up, and histology confirmed simple, uncomplicated appendicitis in 10 (4.4% of 226) patients. Among a subset of 53 patients managed nonoperatively with available Alvarado and/or Pediatric Appendicitis Scores and sonographic appendix diameters in clinical reports, 29 met the criteria for a high probability of appendicitis. Three of these patients (10.3% of 29) underwent secondary appendectomy. No complications were reported during follow-up. CONCLUSIONS: A conservative, antibiotic-free approach may be considered for pediatric patients with suspected uncomplicated appendicitis in a hospital setting. Only between 6 and 10% of these patients required secondary appendectomy. Nevertheless, the cohort of patients treated nonoperatively was likely to have also included individuals with further abdominal conditions other than appendicitis. Active observation and clinical support during the disease course may help patients avoid unnecessary procedures and contribute to spontaneous resolution of appendicitis or other pediatric conditions as the cause of abdominal pain. However, further studies are needed to define validated diagnostic and management criteria.

Good outcomes after repeated pediatric liver retransplantations: A justified procedure even in times of organ shortage.

BACKGROUND: Pediatric liver transplantations generally represent advanced surgery for selected patients. In case of acute or chronic graft failure, biliary or vessel complications, a retransplantation (reLT) can be necessary. In these situations massive adhesions, critical patient condition or lack of good vessels for anastomosis often are problematic. METHODS: Between 2008 and 2021, 208 pediatric patients received a liver transplantation at our center. Retrospectively, all cases with at least one retransplantation were identified and stored in a database. Indication, intra- and postoperative course and overall survival (OS) were analyzed. RESULTS: Altogether 31 patients (14.9%) received a reLT. In 22 cases only one reLT was done, 8 patients received 2 reLTs and 1 patient needed a fourth graft. Median age for primary transplantation, first, second and third reLT was 14 (range: 1-192 months), 60.5 (range: 1-215 months), 58.5 (range: 14-131 months) and 67 months, respectively. Although biliary atresia (42%) and acute liver failure (23%) represented the main indications for the primary liver transplantation, acute and chronic graft failure (1st reLT: 36%, 2nd reLT: 38%), hepatic artery thrombosis (1st reLT: 29%, 2nd reLT: 25%, 3rd reLT: 100%) and biliary complications (1st reLT: 26%, 2nd reLT: 37%) were the most frequent indications for reLT. OS was 81.8% for patients with 1 reLT, 87.5% with 2 reLTs and 100% with 3 reLTs. CONCLUSION: Pediatric liver retransplantation is possible with a good outcome even after multiple retransplantations in specialized centers. Nevertheless, careful patient and graft selection, as well as good preoperative conditioning, are essential.

Immune profile of patients with peritoneal carcinomatosis selected for CRS-HIPEC therapy.

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment option for peritoneal carcinomatosis (PC) from colorectal cancer (CRC), which is otherwise a terminal stage of disease. Nevertheless, survival outcomes are only marginally superior to other treatments. This fact highlights the need for better strategies to control intra-abdominal disease recurrence after CRS-HIPEC, including the complementary use of immunotherapies. The aim of this study was therefore to investigate the immune phenotype of T cells in patients with PC. Fifty three patients with CRC (34 patients with PC and 19 patients without PC) were enrolled in a prospective study (clinicaltrials.gov: NCT04108936). Peripheral blood and omental fat were collected to isolate peripheral blood mononuclear cells (PBMCs) and adipose tissue mononuclear cells (ATMCs). These cells were analysed by flow cytometry using a panel focused upon T cell memory differentiation and exhaustion markers. We found a more naïve profile for CD8+ T cells in peripheral blood and intra-abdominal fat of PC patients compared to comparator group (CG) patients. Furthermore, there was an over-representation of CD4+ T cells expressing inhibitory receptors in adipose tissue of PC patients, but not in blood. Our description of intraperitoneal T cell subsets gives us a better understanding of how peritoneal carcinomatosis shapes local immune responses.

Immunomodulation of Natural Killer Cell Function by Ribavirin Involves TYK-2 Activation and Subsequent Increased IFN-γ Secretion in the Context of In Vitro Hepatitis E Virus Infection.

Hepatitis E virus (HEV) is a major cause of acute hepatitis globally. Chronic and fulminant courses are observed especially in immunocompromised transplant recipients since administration of ribavirin (RBV) does not always lead to a sustained virologic response. By in vitro stimulation of NK cells through hepatoma cell lines inoculated with a full-length HEV and treatment with RBV, we analyzed the viral replication and cell response to further elucidate the mechanism of action of RBV on immune cells, especially NK cells, in the context of HEV infection. Co-culture of HEV-infected hepatoma cells with PBMCs and treatment with RBV both resulted in a decrease in viral replication, which in combination showed an additive effect. An analysis of NK cell functions after stimulation revealed evidence of reduced cytotoxicity by decreased TRAIL and CD107a degranulation. Simultaneously, IFN-É£ production was significantly increased through the IL-12R pathway. Although there was no direct effect on the IL-12R subunits, downstream events starting with TYK-2 and subsequently pSTAT4 were upregulated. In conclusion, we showed that RBV has an immunomodulatory effect on the IL-12R pathway of NK cells via TYK-2. This subsequently leads to an enhanced IFN-É£ response and thus, to an additive antiviral effect in the context of an in vitro HEV infection.

Phenotypic Characterization of Colorectal Liver Metastases: Capsule versus No Capsule and the Potential Role of Epithelial Mesenchymal Transition.

Background: Colorectal liver metastases (CRLM) can be encased in a fibrous capsule separating cancer from normal liver tissue, which correlates with increased patient survival. This study investigated the cellular and molecular components of capsule formation and the possible role of epithelial mesenchymal transition (EMT). Methods: From 222 patients with CRLM, 84 patients (37.8%) were categorized to have CRLM encased with a capsule. A total of 34 CRLM from 34 selected patients was analyzed in detail by EMT pathway-profiling and custom PCR arrays to identify differences in gene expression between CRLM with (n = 20) and without capsule (n = 14). In parallel, those 34 CRLM were used to analyze 16 gene products at the metastasis margin via immunohistochemistry. Results: Encapsulated CRLM showed an elevated expression of signal transduction pathways and effector molecules involved in EMT. E-cadherin and keratin-19 were more prevalent, and transcription as well as translation (immunohistochemistry) of pGSK-3-ß, SOX10, tomoregulin-1, and caldesmon were increased. By contrast, the loss of E-cadherin and the prevalence of snail-1 were increased in CRLM without capsule. Collagen I and III and versican were identified as capsule components with extracellular matrix fibers running concentrically around the malignant tissue and parallel to the invasive front. Caldesmon was also demonstrated as a capsule constituent. Conclusions: The fibrous capsule around CRLM can be produced by cells with mesenchymal characteristics. It functions as a protective border by both the features of fiber architecture and the inhibition of invasive growth through EMT recruiting mesenchymal cells such as myofibroblasts by transformation of surrounding epithelial or even carcinoma cells. By contrast, EMT demonstrated in non-encapsulated CRLM may lead to a more mesenchymal, mobile, and tissue-destructive carcinoma cell phenotype and facilitate malignant spread.

Early γGT and bilirubin levels as biomarkers for regeneration and outcomes in damaged bile ducts after liver transplantation.

BACKGROUND: Early patient and allograft survival after liver transplantation (LT) depend primarily on parenchymal function, but long-term allograft success relies often on biliary-tree function. We examined parameters related to cholangiocyte damage that predict poor long-term LT outcomes after donation after brain death (DBD). METHODS: Sixty bile ducts (BD) were assessed by a BD damage-score and divided into groups with "major" BD-damage (n = 33) and "no relevant" damage (n = 27) during static cold storage. Patients with "major" BD damage were further investigated by measuring biliary excretion parameters in the first 14 days post-LT (followed-up for 60-months). RESULTS: Patients who received LT showing "major" BD damage had significantly worse long-term patient survival, versus grafts with "no relevant" damage (p = .03). When "major" BD damage developed, low bilirubin levels (p = .012) and high gamma-glutamyl transferase (GGT)/bilirubin ratio (p = .0003) were evident in the early post-LT phase (7-14 days) in patients who survived (> 60 months), compared to those who did not. "High risk" patients with bile duct damage and low GGT/bilirubin ratio had significantly shorter overall survival (p < .0001). CONCLUSIONS: Once "major" BD damage occurs, a high GGT/bilirubin ratio in the early post-operative phase is likely indicator of liver and cholangiocyte regeneration, and thus a harbinger of good overall outcomes. "Major" BD damage without markers of regeneration identifies LT patients that could benefit from future repair therapies.

Characteristics and outcome of patients with small bowel adenocarcinoma (SBA).

BACKGROUND: Small bowel adenocarcinoma (SBA) remains a rare malignancy accounting for less than 5% of all the gastrointestinal tract cancers. However, only limited data and expert guidelines are available for this entity. As a result, treatment concepts are predominantly derived from colorectal cancer. METHODS: To substantiate data on the course of disease, diagnosis and treatment of SBA, we performed a population-based analysis from a Bavarian population of 2.2 million people. RESULTS: We identified 223 patients with SBA. Mean age at diagnosis was 67.8 years and patients were diagnosed rather late (34.5% UICC stage IV). Largest proportion of these patients were diagnosed with adenocarcinoma of the duodenum (132 patients, 59.2%) and most patients were diagnosed with late stage cancer, stage IV (70 patients, 31.4%). With respect to treatment, most patients underwent primary surgery (187 patients, 84.6%). Systemic therapy seemed to have an impact in UICC stage IV patients but not in UICC stage IIB or III. The 5-year survival rate was 29.0%. This was significantly less compared to colon cancer in the same cohort, which was 50.0%. Furthermore, median survival of patients with small bowel cancer was only 2.0 years (95% CI 1.4-2.5) compared to 4.9 years (95% CI 4.8-5.1) of patients with colon cancer. CONCLUSION: SBA showed a distinct epidemiology compared to colon cancer. Thus, data acquisition particularly on systemic treatment are paramount, with the objective to complement the available guidelines.

Biological abdominal wall expansion in pediatric liver recipients after transplantation with large-for-size organs.

BACKGROUND: After pediatric split liver transplantation, intra-abdominal loss of domain due to large-for-size left lateral grafts is a frequent problem for fascial closure and potentially leads to reduced liver perfusion and abdominal compartment syndrome. Therefore, delayed fascial closure with the use of temporary silastic meshes and reoperation or alternative fascial bridging procedures are necessary. METHODS: Between March 2019 and October 2021, biologic meshes were used for abdominal wall expansion in 6 cases of pediatric split liver transplantation. These cases were analyzed retrospectively. RESULTS: One male and 5 female children with median age of 6 months (range: 0-57 months) and weight of 6 kg (range: 3.5-22 kg) received a large-for-size left lateral graft. Graft-to-recipient weight ratio (GRWR) was 4.8% (range: 1.5%-8.5%) in median. Biologic mesh implantation for abdominal wall expansion was done in median 7 days (range: 3-11 days) after transplantation when signs of abdominal compartment syndrome with portal vein thrombosis in 3 and of the liver artery in 1 case occurred. In 2 cases, bovine acellular collagen matrix and 4 cases ovine reinforced tissue matrix was used. Median follow-up was 12.5 months (range: 4-28 months) and showed good liver perfusion by sonography and normal corporal development without signs of ventral hernia. One patient died because of fulminant graft rejection and emergency re-transplantation 11 months after the initial transplantation. CONCLUSIONS: Biologic meshes can be used as safe method for abdominal wall expansion to achieve fascial closure in large-for-size liver transplant recipients. Usage for primary fascial closure can be considered in selected patients.

Semiresorbable biologic hybrid meshes for ventral abdominal hernia repair in potentially contaminated settings: lower risk of recurrence.

In case of potential contamination, implantation of synthetic meshes in hernia and abdominal wall surgery is problematic due to a higher risk of mesh infection. As an alternative, a variety of different biologic meshes have been used. However, relevant data comparing outcome after implantation of these meshes are lacking. Between January 2012 and October 2021, biologic meshes were used for reconstruction of the abdominal wall in 71 patients with preoperative or intraoperative abdominal contamination. In this retrospective study, semiresorbable biologic hybrid meshes (BHM) and completely resorbable meshes (CRM) were compared and analyzed using a Castor EDC database. In 28 patients, semiresorbable biologic hybrid meshes were used; in 43 patients, completely resorbable meshes were used. Both groups showed no difference in age, gender, BMI, operation duration, hernia size and Charlson comorbidity index. The risk degree of surgical-site occurrences was graded according to the Ventral Hernia Working Group (VHWG) classification, and the median value was 3 (range 2-4) in the BHM group and 3 (range 2-4) in the CRM group. Hernia recurrence within 24 months after hernia repair was significantly lower in the BHM group (3.6% vs. 28.9%; p = 0.03), while postoperative complication rate, with respect to seromas in need of therapy (61.4% vs. 55.5%, p = 0.43) and operative revision (28.6% vs. 16.3%, p = 0.22) was not different in either group. Biologic hybrid meshes can be used safely in case of possible contamination. BHM seems to reduce the risk of hernia recurrence compared to completely resorbable biologic meshes, but this has to be investigated further.

External validation of biomarkers for immune-related adverse events after immune checkpoint inhibition.

Immune checkpoint inhibitors have revolutionized treatment of advanced melanoma, but commonly cause serious immune-mediated complications. The clinical ambition of reserving more aggressive therapies for patients least likely to experience immune-related adverse events (irAE) has driven an extensive search for predictive biomarkers. Here, we externally validate the performance of 59 previously reported markers of irAE risk in a new cohort of 110 patients receiving Nivolumab (anti-PD1) and Ipilimumab (anti-CTLA-4) therapy. Alone or combined, the discriminatory value of these routine clinical parameters and flow cytometry biomarkers was poor. Unsupervised clustering of flow cytometry data returned four T cell subsets with higher discriminatory capacity for colitis than previously reported populations, but they cannot be considered as reliable classifiers. Although mechanisms predisposing some patients to particular irAEs have been described, we are presently unable to capture adequate information from pre-therapy flow cytometry and clinical data to reliably predict risk of irAE in most cases.

3D In Vivo Models for Translational Research on Pancreatic Cancer: The Chorioallantoic Membrane (CAM) Model.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer with adverse outcomes that have barely improved over the last decade. About half of all patients present with metastasis at the time of diagnosis, and the 5-year overall survival rate across all stages is only 6%. Innovative in vivo research models are necessary to combat this cancer and to discover novel treatment strategies. The chorioallantoic membrane (CAM) model represents one 3D in vivo methodology that has been used in a large number of studies on different cancer types for over a century. This model is based on a membrane formed within fertilized chicken eggs that contain a dense network of blood vessels. Because of its high cost-efficiency, simplicity, and versatility, the CAM model appears to be a highly valuable research tool in the pursuit of gaining more in-depth insights into PDAC. A summary of the current literature on the usage of the CAM model for the investigation of PDAC was conducted and subdivided into angiogenesis, drug testing, modifications, personalized medicine, and further developments. On this comprehensive basis, further research should be conducted on PDAC in order to improve the abysmal prognosis of this malignant disease.

Second Cancer After Additive Chemotherapy in Patients With Colon Cancer.

BACKGROUND: Additive chemotherapeutic treatment of UICC-stage -III / IV colon cancer with fluorouracil, leucovorin and oxaliplatin is widely accepted as current standard of treatment after R0-resection. However, as patients.. survival is increasing, long-term side effects of chemotherapeutic agents such as second cancer development are becoming increasingly important. PATIENTS: We therefore investigated a total of 2 856 Patients with UICC-stage III / IV colon cancer, 223 of whom (7.8%) had developed a subsequent second cancer. RESULTS: Median follow-up was 73.2 months (range 209.9 months, 95%-CI 69.8-76.9). Most frequent second cancers were prostate cancer (18.4%), colon cancer (16.1%), breast cancers (8.1%), lung cancer (8.1%), rectal cancer (4.9%) and uterine cancer (4.9%). However, in comparison to non-treated patients this did not represent a significantly increased risk for subsequent second cancer in patients after treatment with additive chemotherapy. Of interest, our data suggest a significantly decreased second cancer rate in patients treated with FOLFOX compared to FUFOL for additive treatment. CONCLUSIONS: Second cancer development was not increased after additive chemotherapy for colon cancer, which is a novel aspect in the ongoing discussions on reduction of adjuvant treatment to 3 months or treatment of lymph node negative patients. Novelty and Impact Statement To our knowledge, this is the first population-based study analyzing second cancer development after additive chemotherapy in patients with UICC III-IV colon cancer. The results have an important impact on the surveillance and long-term follow-up of cancer patients.

A 3D In Vivo Model for Studying Human Renal Cystic Tissue and Mouse Kidney Slices.

(1) Background: Autosomal dominant polycystic kidney disease (ADPKD) is a frequent monogenic disorder that leads to progressive renal cyst growth and renal failure. Strategies to inhibit cyst growth in non-human cyst models have often failed in clinical trials. There is a significant need for models that enable studies of human cyst growth and drug trials. (2) Methods: Renal tissue from ADPKD patients who received a nephrectomy as well as adult mouse kidney slices were cultured on a chorioallantoic membrane (CAM) for one week. The cyst volume was monitored by microscopic and CT-based applications. The weight and angiogenesis were quantified. Morphometric and histological analyses were performed after the removal of the tissues from the CAM. (3) Results: The mouse and human renal tissue mostly remained vital for about one week on the CAM. The growth of cystic tissue was evaluated using microscopic and CT-based volume measurements, which correlated with weight and an increase in angiogenesis, and was accompanied by cyst cell proliferation. (4) Conclusions: The CAM model might bridge the gap between animal studies and clinical trials of human cyst growth, and provide a drug-testing platform for the inhibition of cyst enlargement. Real-time analyses of mouse kidney tissue may provide insights into renal physiology and reduce the need for animal experiments.

Covid19 vaccination-associated portal vein thrombosis-An interdisciplinary clinical challenge.

Despite one of the largest vaccination campaigns in human history, the COVID-19 pandemic has not been yet defeated. More than 10 billion doses of COVID-19 vaccine have been administered worldwide. AstraZeneca's Vaxzevria (ChAdOx1 nCoV-19 / AZD1222) was approved as the first viral vector-based vaccine in the EU on 29 January 2021. Thromboembolic events are a rare complication of vaccination with ChAdOx1 nCoV-19 in the context of, now known as vaccine-induced immune thrombotic thrombocytopenia (VITT), with an incidence of 1.5-3 in 100,000 vaccinations. VITT is clinically as well as pathophysiologically comparable to heparin-induced thrombocytopenia. Illustrated by a fulminant patient case, a multidisciplinary step-by-step guideline was developed for the recognition, diagnosis, and management of patients with severe acute portosplanchic venous thrombosis with mesenteric ischemia due to vaccine-induced immunogenic thrombotic thrombocytopenia.

Predictors of portal vein complications after pediatric liver transplantation: A German center experience.

BACKGROUND: Portal vein complications (PVCs) after pediatric liver transplantation (LT) are sometimes asymptomatic, especially in the early phase, and can threaten both the graft and patient's survival. Therefore, the purpose of this study is to analyze the risk factors for portal vein thrombosis (PVT) and portal vein stenosis (PVS) after pediatric LT. METHODS: All pediatric patients (n = 115) who underwent primary LT at Regensburg University Hospital between January 2010 and April 2017 were included in this study. The pre-, intra-, and postoperative parameters of all patients were retrospectively reviewed and risk factors for both PVT and PVS were analyzed. RESULTS: Of the 115 patients, living donor LT was performed on 57 (49.5%) patients, and biliary atresia was the primary diagnosis in 65 patients (56%). After pediatric LT, 9% of patients developed PVT, and 16.5% developed PVS. Patient weight ≤7 kg [odds ratio (OR) 9.35, 95% confidence interval (CI) 1.03-84.9, p = .04] and GRWR >3% (OR 15.4, 95% CI 1.98-129.5, p = .01) were the independent risk factors for the development of PVT and PVS, respectively upon multivariate analysis. The overall patient survival rates at 1, 3, and 5 years were 91%, 90%, and 89%, respectively, and there was no difference in patient survival among those with and without PVCs. CONCLUSIONS: Pediatric patients with body weight <7 kg and/or receiving a graft with GRWR >3% may develop PVCs and so require certain surgical modifications, close follow-up, and prophylactic anticoagulant therapy following transplant.

Timing of Closure of a Protective Loop-Ileostomy Can Be Crucial for Restoration of a Functional Digestion.

Introduction: Protective loop-ileostomy is one of the most common interventions in abdominal surgery to provide an alternative intestinal outlet until sufficient healing of a distal anastomosis has occurred. However, closure of a loop-ileostomy is also associated with complications. Thus, knowledge of the optimal time interval between primary and secondary surgery is crucial. Methods: Data from 409 patients were retrospectively analyzed regarding complications and risk factors in closure-associated morbidity and mortality. A modified Clavien-Dindo classification of surgical complications was used to evaluate the severity of complications. Results: A total of 96 (23.5%) patients suffered from postoperative complications after the closure of the loop-ileostomy. Early closure within 150 days from enterostomy (n = 229) was associated with less complications (p < 0.001**). Looking at the severity of complications, there were significantly more (p = 0.014*) mild postoperative complications in the late closure group (>150 days). Dysfunctional digestive problems-either (sub-) ileus (p = 0.004*), diarrhea or stool incontinence (p = 0.003*)-were the most frequent complications associated with late closure. Finally, we could validate in a multivariate analysis that "time to closure" (p = 0.002*) is independently associated with the development of complications after closure of a protective loop-ileostomy. Conclusion: Late closure (>150 days) of a loop-ileostomy is an independent risk factor in post-closure complications in a multivariate analysis. Nevertheless, circumstances of disease and therapy need to be considered when scheduling the closure procedure.

Positive Microbiological Cultures in the Respiratory Tract of High Model for End-Stage Liver Disease (MELD) Liver Transplant Recipients With and Without Pneumonia.

BACKGROUND: Pneumonia in liver transplant recipients is one of the most common infections in the early phase after transplantation. The diagnosis is based on clinical signs combined with positive microbiological samples taken from the lower respiratory tract. However, the role of bacterial colonization is not clear, nor is its association with pneumonia or its long-term consequences. The aim of this study was to investigate the association between positive microbiological findings and clinically relevant pneumonia and analyze different clinical and laboratory parameters for their association with pneumonia in liver transplant recipients. METHODS: This was a retrospective analysis of 266 adult orthotopic liver transplantations between January 2008 and December 2013. A multidisciplinary in-house specialist panel established and confirmed the diagnosis of clinically relevant pneumonia in microbiologically positive patients. RESULTS: Of the 266 transplantations analyzed, 54 patients (20%) showed microbiologically positive trachea-bronchial cultures during the first 21 days after liver transplantation. Of those 54 patients, 24 (44.4%) had pneumonia as rated by the multidisciplinary specialist panel. Presence of gram-negative Enterobacteriaceae (P = .013) and positive chest radiologic findings (P = .035) were associated with pneumonia in microbiological-positive patients. Although patients with pneumonia had the lowest long-term survival, those without pneumonia but with positive microbiological cultures had still worse survival compared with the Model for End-Stage Liver Disease-matched control group without positive cultures (P = .012). CONCLUSIONS: Gram-negative Enterobacteriaceae and positive radiologic findings were associated with pneumonia in liver transplant recipients with positive microbiological trachea-bronchial cultures. Recipients with bacterial colonization without pneumonia also showed decreased long-term survival.

Early Everolimus-Facilitated Reduced Tacrolimus in Liver Transplantation: Results From the Randomized HEPHAISTOS Trial.

Everolimus-facilitated reduced-exposure tacrolimus (EVR + rTAC) at 30 days after liver transplantation (LT) has shown advantages in renal preservation. This study evaluated the effects of early initiation of EVR + rTAC in de novo LT recipients (LTRs). In HEPHAISTOS (NCT01551212, EudraCT 2011-003118-17), a 12-month, multicenter, controlled study, LTRs were randomly assigned at 7 to 21 days after LT to receive EVR + rTAC or standard-exposure tacrolimus (sTAC) with steroids. The primary objective was to demonstrate superior renal function (assessed by estimated glomerular filtration rate [eGFR]) with EVR + rTAC versus sTAC at month 12 in the full analysis set (FAS). Other assessments at month 12 included the evaluation of renal function in compliance set and on-treatment (OT) patients, efficacy (composite endpoint of graft loss, death, or treated biopsy-proven acute rejection [tBPAR] and individual components) in FAS, and safety. In total, 333 patients (EVR + rTAC, 169; sTAC, 164) were included in the FAS. A high proportion of patients was nonadherent in maintaining tacrolimus trough levels (EVR + rTAC, 36.1%; sTAC, 34.7%). At month 12, the adjusted least square mean eGFR was numerically higher with EVR + rTAC versus sTAC (76.2 versus 72.1 mL/minute/1.73 m2 , difference: 4.1 mL/minute/1.73 m2 ; P = 0.097). A significant difference of 8.3 mL/minute/1.73 m2 (P = 0.03) favoring EVR + rTAC was noted in the compliance set. Incidence of composite efficacy endpoint (7.7% versus 7.9%) and tBPAR (7.1% versus 5.5%) at month 12 as well as incidence of treatment-emergent adverse events (AEs) and serious AEs were comparable between groups. A lower proportion of patients discontinued EVR + rTAC than sTAC treatment (27.2% versus 34.1%). Early use of everolimus in combination with rTAC showed comparable efficacy, safety, and well-preserved renal function versus sTAC therapy at month 12. Of note, renal function was significantly enhanced in the compliance set.