Metabolomic Analysis of Human Cirrhosis and Hepatocellular Carcinoma: A Pilot Study.

BACKGROUND: Molecular changes in HCC development are largely unknown. As the liver plays a fundamental role in the body's metabolism, metabolic changes are to be expected. AIMS: We aimed to identify metabolomic changes in HCC in comparison to liver cirrhosis (LC) patients, which could potentially serve as novel biomarkers for HCC diagnosis and prognosis. METHODS: Metabolite expression from 38 HCC from the SORAMIC trial and 32 LC patients were analyzed by mass spectrometry. Metabolites with significant differences between LC and HCC at baseline were analyzed regarding expression over follow-up. In addition, association with overall survival was tested using univariate Cox proportional-hazard analysis. RESULTS: 41 metabolites showed differential expression between LC and HCC patients. 14 metabolites demonstrated significant changes in HCC patients during follow-up. Campesterol, lysophosphatidylcholine, octadecenoic and octadecadienoic acid, and furoylglycine showed a differential expression in the local ablation vs. palliative care group. High expression of eight metabolites (octadecenoic acid, 2-hydroxybutyrate, myo-inositol, isocitrate, erythronic acid, creatinine, pseudouridine, and erythrol) were associated with poor overall survival. The association between poor OS and octadecenoic acid and creatinine remained statistically significant even after adjusting for tumor burden and LC severity. CONCLUSION: Our findings give promising insides into the metabolic changes during HCC carcinogenesis and provide candidate biomarkers for future studies. Campesterol and furoylglycine in particular were identified as possible biomarkers for HCC progression. Moreover, eight metabolites were detected as predictors for poor overall survival.

Nomenclature, diagnosis and management of drug-induced autoimmune-like hepatitis (DI-ALH): An expert opinion meeting report.

Drug-induced liver injury (DILI) can mimic almost all other liver disorders. A phenotype increasingly ascribed to drugs is autoimmune-like hepatitis (ALH). This article summarises the major topics discussed at a joint International Conference held between the Drug-Induced Liver Injury consortium and the International Autoimmune Hepatitis Group. DI-ALH is a liver injury with laboratory and/or histological features that may be indistinguishable from those of autoimmune hepatitis (AIH). Previous studies have revealed that patients with DI-ALH and those with idiopathic AIH have very similar clinical, biochemical, immunological and histological features. Differentiating DI-ALH from AIH is important as patients with DI-ALH rarely require long-term immunosuppression and the condition often resolves spontaneously after withdrawal of the implicated drug, whereas patients with AIH mostly require long-term immunosuppression. Therefore, revision of the diagnosis on long-term follow-up may be necessary in some cases. More than 40 different drugs including nitrofurantoin, methyldopa, hydralazine, minocycline, infliximab, herbal and dietary supplements (such as Khat and Tinospora cordifolia) have been implicated in DI-ALH. Understanding of DI-ALH is limited by the lack of specific markers of the disease that could allow for a precise diagnosis, while there is similarly no single feature which is diagnostic of AIH. We propose a management algorithm for patients with liver injury and an autoimmune phenotype. There is an urgent need to prospectively evaluate patients with DI-ALH systematically to enable definitive characterisation of this condition.

A new framework for advancing in drug-induced liver injury research. The Prospective European DILI Registry.

BACKGROUND & AIMS: No multi-national prospective study of drug-induced liver injury (DILI) has originated in Europe. The design of a prospective European DILI registry, clinical features and short-term outcomes of the cases and controls is reported. METHODS: Patients with suspected DILI were prospectively enrolled in the United Kingdom, Spain, Germany, Switzerland, Portugal and Iceland, 2016-2021. DILI cases or non-DILI acute liver injury controls following causality assessment were enrolled. RESULTS: Of 446 adjudicated patients, 246 DILI patients and 100 had acute liver injury due to other aetiologies, mostly autoimmune hepatitis (n = 42) and viral hepatitis (n = 34). DILI patients (mean age 56 years), 57% women, 60% with jaundice and 3.6% had pre-existing liver disease. DILI cases and non-DILI acute liver injury controls had similar demographics, clinical features and outcomes. A single agent was implicated in 199 (81%) DILI cases. Amoxicillin-clavulanate, flucloxacillin, atorvastatin, nivolumab/ipilimumab, infliximab and nitrofurantoin were the most commonly implicated drugs. Multiple conventional medications were implicated in 37 (15%) and 18 cases were caused by herbal and dietary supplements. The most common single causative drug classes were antibacterials (40%) and antineoplastic/immunomodulating agents (27%). Overall, 13 (5.3%) had drug-induced autoimmune-like hepatitis due to nitrofurantoin, methyldopa, infliximab, methylprednisolone and minocycline. Only six (2.4%) DILI patients died (50% had liver-related death), and another six received liver transplantation. CONCLUSIONS: In this first multi-national European prospective DILI Registry study, antibacterials were the most commonly implicated medications, whereas antineoplastic and immunomodulating agents accounted for higher proportion of DILI than previously described. This European initiative provides an important opportunity to advance the study on DILI.

Relapse and Need for Extended Immunosuppression: Novel Features of Drug-Induced Autoimmune Hepatitis.

BACKGROUND: Drug-induced autoimmune hepatitis (DI-AIH) has been proposed as a distinct phenotype of drug-induced liver injury (DILI), and frequently has been associated with specific drugs, such as minocycline and nitrofurantoin. However, no clear definition of DI-AIH has been established thus far. OBJECTIVES: We aimed to identify features distinguishing DI-AIH from DILI and idiopathic autoimmune hepatitis (AIH) in an attempt to further define a DI-AIH phenotype. METHOD: A cohort of 38 previously reported DILI and AIH patients who were prospectively recruited at our tertiary centre and who received corticosteroid was analysed regarding the phenotypical presentation and outcome of DI-AIH, DILI, and AIH. RESULTS: AIH (n = 19), DILI (n = 8), and DI-AIH (n = 11) patients presented with similar clinical features at onset, with the only difference being a higher Roussel Uclaf Causality Assessment Method (RUCAM) score in the DILI and DI-AIH patients. Post-treatment AIH scores were lower and a more rapid decrease of alanine aminotransferase in the first week of corticosteroid treatment was observed in both DILI groups when compared to AIH patients, while no significant differences were observed between DI-AIH and DILI patients. Relapse occurred in DI-AIH but not in DILI patients (36% vs. 0%) with a more frequent need for long-term immunosuppression (27% vs. 13%). CONCLUSIONS: Our data show that relapse after cessation of corticosteroids and need for further immunosuppressive treatment does occur in a substantial proportion of DI-AIH patients. However, no other phenotypical differences between DILI due to agents commonly associated with DI-AIH and DILI due to other drugs were identified.

Can thiamine substitution restore cognitive function in alcohol use disorder?

AIMS: While clinical consequences of thiamine deficiency in alcohol use disorder (AUD) are severe, evidence-based recommendations on dosage, type of administration and duration of thiamine substitution (TS), and its' target levels remain sparse. This study aimed to compare the effect of two best practice TS regimens on thiamine blood levels (i.e. thiamine pyrophosphate, TPP) and cognitive function. METHODS: In 50 patients undergoing in-patient alcohol-withdrawal treatment, TPP levels were determined at baseline and end of weeks 1, 2 and 8 following administration of oral TS (3 × 100 mg/day for 7 days followed by 1 × 100 mg/day thereafter) either with or without preceding intravenous TS (3 × 100 mg/day for 5 days). An extensive psychiatric assessment was conducted at baseline, including an evaluation of AUD severity and depressive symptoms. Additionally, cognitive function and depressive symptoms were repeatedly evaluated. RESULTS: Relevant increases (mean increase by 100.2 nmol/l [CI 76.5-123.8], P < 0.001) in peripheral blood TPP levels were observed in all patients at the end of weeks 1 and 2. Furthermore, no relevant difference between the intravenous and the oral group was found (average difference between increases: 2.3 nmol/l, P = 0.912). Importantly, an association between the 'extent of the response' to TS and the performance in a memory task was revealed in secondary analyses. CONCLUSION: TS was associated with improving cognitive function in patients with AUD, independently of the substitution regime. Thus, in clinical practice, oral TS might be a sufficient but obligatory medication to prevent cognitive decline in AUD in the absence of Wernicke-Korsakoff Syndrome.

Challenges and Future of Drug-Induced Liver Injury Research-Laboratory Tests.

Drug-induced liver injury (DILI) is a rare but potentially severe adverse drug event, which is also a major cause of study cessation and market withdrawal during drug development. Since no acknowledged diagnostic tests are available, DILI diagnosis poses a major challenge both in clinical practice as well as in pharmacovigilance. Differentiation from other liver diseases and the identification of the causative agent in the case of polymedication are the main issues that clinicians and drug developers face in this regard. Thus, efforts have been made to establish diagnostic testing methods and biomarkers in order to safely diagnose DILI and ensure a distinguishment from alternative liver pathologies. This review provides an overview of the diagnostic methods used in differential diagnosis, especially with regards to autoimmune hepatitis (AIH) and drug-induced autoimmune hepatitis (DI-AIH), in vitro causality methods using individual blood samples, biomarkers for diagnosis and severity prediction, as well as experimental predictive models utilized in pre-clinical settings during drug development regimes.

Liver function test abnormalities at hospital admission are associated with severe course of SARS-CoV-2 infection: a prospective cohort study.

OBJECTIVE: Liver injury has frequently been reported in COVID-19 patients. The clinical relevance of liver injury related to SARS-CoV-2 infection remains unclear with a need for prospective studies on the impact of liver function test (LFT) abnormalities at baseline. DESIGN: Data of 217 patients without pre-existing liver disease prospectively included in the COVID-19 registry of the LMU university hospital were analysed in order to assess the association of abnormal LFT at admission and course of the disease. Severe course was defined as admission to the intensive care unit (ICU) or as COVID-19-related death. RESULTS: Abnormal LFT at baseline was present in 58% of patients, with a predominant elevation of aspartate aminotransferase (AST) (42%), gamma-glutamyltransferase (GGT) (37%) and alanine aminotransferase (ALT) (27%), hypoalbuminaemia was observed in 33%. Elevation of ALT and GGT, as well as hypoalbuminaemia, was associated with higher proportions of patients requiring ICU treatment and mechanical ventilation. After adjusting for age, gender and comorbidities, hypoalbuminaemia combined with abnormal AST or GGT at hospital admission was a highly significant independent risk factor for ICU admission (OR 46.22 and 38.8, respectively) and for a composite endpoint of ICU admission and/or COVID-19-related death (OR 42.0 and 26.9, respectively). CONCLUSION: Abnormal LFTs at hospital admission, in particular GGT and albumin, are associated with a severe course of SARS-CoV-2 infection.

Antimitochondrial Rather than Antinuclear Antibodies Correlate with Severe Drug-Induced Liver Injury.

INTRODUCTION: A proportion of patients with drug-induced liver injury (DILI) present with autoantibodies, which has led to the current concept of autoimmune-like DILI. However, no standardized definition exists and the clinical relevance has not been studied in detail yet. METHODS: 143 patients with DILI enrolled in a prospective study were analyzed. DILI diagnosis was based on the monocyte-derived hepatocyte-like cell test and supported by Roussel Uclaf Causality Assessment Method (RUCAM) and expert adjudication. Testing for antinuclear antibodies (ANA) and antimitochondrial antibodies (AMA) was performed using immunofluorescence. ANA titers ≥1:100 were considered positive and ≥1:400 clinically relevant; AMA positivity was considered at titers ≥1:100. RESULTS: 67% exhibited ANA ≥1:100 and 29% ANA ≥1:400; 10% were AMA positive. There was no significant correlation between the ANA titers and the causative drug, while AMA positive patients had taken nonsteroidal anti-inflammatory drugs more frequently. No difference was seen regarding clinical characteristics or laboratory parameters in patients with ANA ≥1:400, while patients with positive AMA presented with higher aminotransferases, bilirubin, and international normalized ratio. Significantly higher proportions of patients with ANA ≥1:400 or AMA positivity exhibited elevated immunoglobulin G levels. AMA positivity but not elevated ANA titers correlated with a higher proportion of Hy's law positivity. CONCLUSION: A closer look in a causality proven DILI cohort provided no evidence that presence of ANA titers is specific for DILI by a certain medication. AMA rather than ANA positivity was related to a more pronounced liver injury.

Monocyte-Derived Hepatocyte-Like Cell Test: A Novel Tool for in vitro Identification of Drug-Induced Liver Injury in Patients with Herbal or Dietary Supplements.

BACKGROUND: Drug-induced liver injury caused by herbal and dietary supplements (HDS) has been an increasingly important phenomenon in recent years. Diagnosis is the major challenge. Definite causality assessment, especially in patients with concomitant prescription medicine or other potential causes of liver injury, can be impossible. OBJECTIVES: We investigated the usefulness of an in vitro test on the basis of peripheral monocytes of the individual patients in patients with acute liver injury consuming HDS. METHOD: Patients with acute liver injury who had been prospectively recruited by the University Hospital Munich (LMU, Munich) and the Chinese University of Hong Kong (CUHK) and who took at least 1 HDS were selected for this analysis. Diagnosis of drug-induced liver injury (DILI) was based on local expert adjudication, Roussel Uclaf Causality Assessment Method (RUCAM) score, and course of the disease and was supported by the monocyte-derived hepatocyte-like (MH) cell test. RESULTS: We identified 47 patients with liver injury and intake of at least 1 HDS: 32 (68%) were diagnosed with DILI. HDS was determined as the causative agent in 28 out of those 32 patients. The MH cell test could correctly identify 29 out of those 32 DILI cases and showed false positive results in only 2 out of the 15 non-DILI patients. The MH cell test therefore reached a sensitivity and specificity of 90.6 and 86.7%, respectively, in patients with acute liver injury and HDS intake. CONCLUSIONS: Our data provide evidence that the MH cell test can be a useful tool to identify the role of HDS in causing DILI and therefore support causality assessment in patients consuming HDS.

Early ALT response to corticosteroid treatment distinguishes idiosyncratic drug-induced liver injury from autoimmune hepatitis.

BACKGROUND: Drug-induced liver injury (DILI) and idiopathic autoimmune hepatitis (AIH) are competing diagnoses in patients with acute liver injury (ALI) and drug intake. In absence of unequivocal markers, scores like RUCAM and AIH are used to distinguish both entities. However, in some cases the diagnosis remains ambiguous. Our aim was to identify a simple parameter to discriminate DILI and AIH shortly after starting corticosteroid treatment. METHODS: For the current analysis, 44 patients with ALI who took at least one drug and who received corticosteroids were included and comprised 22 DILI and 22 AIH cases. Scores of AIH and RUCAM were calculated at initial presentation, the final diagnosis was made from analysing the course of disease. Changes in the serum alanine aminotransferase (ALT) concentrations after starting corticosteroid treatment were determined and compared between the DILI and AIH groups. RESULTS: Fifty-nine per cent of patients (n = 26) were correctly classified at presentation by AIH score and RUCAM respectively. However, in one-third (n = 13) of the 44 patients, results were inconclusive and five other patients were misclassified. The decrease in ALT levels 1 week after the initiation of steroid therapy was significantly more pronounced in patients with the final diagnosis of DILI than in AIH patients (accuracy 77%). This difference was also observed in the 18 initially misclassified or inconclusive cases (accuracy 83%). CONCLUSION: Short-term response of ALT to corticosteroid therapy helps to differentiate DILI and AIH. This finding may be helpful in treatment decision for patients with inconclusive diagnostic scores.

[Compatibility of Work and Family Life: Survey of Physicians in the Munich Metropolitan Area]. / Vereinbarkeit von Familie und Arztberuf ­ eine repräsentative Umfrage in München bei Ärztinnen und Ärzten unterschiedlicher Tätigkeitsbereiche.

AIM: Investigation of the compatibility of work and family life for physicians in the Munich metropolitan area. METHODS: Survey of a representative sample of 1,800 physicians using a questionnaire. RESULTS: Men were less satisfied (7% very satisfied vs. 21%) with compatibility between work and family life than women. The group least satisfied overall was hospital-based physicians (p=0.000, chi-square=122.75). Women rather than men cut back their career due to children, perceived their professional advancement as impaired, desisted from establishing private practice or quit hospital employment altogether. Respondents strove for flexible childcare and makeshift solution if the established service failed. Most did not have that at their disposal. Hospital-based physicians wished for predictable working hours, and would like to have a say in the structure of their schedule. For the majority this was not the case. While for 80% it would be important to participate in the definition of their working hours, this was only possible in 17%. 86% found the opportunity to work part-time important, but many doctors (more than 30%) did not have that option. The biggest help for office-based physicians would be an expedited procedure by the Bavarian Association of Statutory Health Insurance Physicians (KVB) when applying for a proxy. The second most important would be the ability to hand over on-call duties. 36% of respondents felt that compatibility of work and family life was best achieved outside of patient care, during residency 42% believed this to be the case. Only 6% of physicians felt the best compatibility to be achieved in a hospital. Among the physician owners of practices, 34% considered their model to be the best way to reconcile both aspects of life. CONCLUSION: More flexible options for childcare and more influence on the definition of working hours are necessary in order to better reconcile work and family life. For office-based physicians it must be made easier to find a substitute. Currently, especially women consider children as hindering their careers. Hospitals are perceived as extremely unfavorable workplaces for achieving compatibility between work and family life.

Development and Validation of a Test to Identify Drugs That Cause Idiosyncratic Drug-Induced Liver Injury.

BACKGROUND & AIMS: Idiosyncratic drug-induced liver injury (iDILI) is one of the most challenging diagnoses in hepatology. It is frequently impossible to identify the agent that has caused iDILI in patients who take multiple medicines. We developed an in vitro method to identify drugs that cause liver injury in patients, based on drug toxicity to monocyte-derived hepatocyte-like (MH) cells from patient blood samples. We then collected data on patients who were re-exposed to drugs found to be toxic in the MH test to validate test performance. METHODS: We performed a prospective study of patients referred to the University Hospital in Munich, Germany, with acute liver injury believed to be caused by medications (300 patients were enrolled in the study and we present data from 40 patients with iDILI and re-exposure to implicated drugs). We collected data from patients on medical history, laboratory test and imaging results, findings from biopsy analyses, and medications taken. Blood samples were collected from all patients and MH cells were isolated and cultured for 10 days. MH cells were then incubated with drugs to which each patient had been exposed, and toxicity was measured based on release of lactate dehydrogenase. Agents found to be toxic to MH cells were considered as candidates for the cause of liver injury. Patients were followed up for up to 6 months after liver injury and data on drug re-exposures and subsequent liver damage within the following 3 to 24 months were associated with findings from MH tests. RESULTS: Our test identified 10 drugs that were toxic to MH cells from 13 patients (amoxicillin/clavulanate to cells from 2 patients; diclofenac to cells from 2 patients; methylprednisolone to cells from 2 patients; and atorvastatin, metamizole, pembrolizumab, piperacillin/tazobactam, moxifloxacin, duloxetine, or sertraline each to cells from 1 patient). Thirteen patients had a recurrence of liver injury after inadvertent re-exposure to a single drug, and the MH test correctly identified 12 of the 13 drugs that caused these liver re-injury events. All 86 drugs that were not toxic to MH cells in our assay were safely resumed by patients and were not associated with liver re-injury in 27 patients. Therefore, the MH test identifies drugs that cause liver injury with 92.3% sensitivity and 100% specificity (1 false-negative and 12 true-positive results). CONCLUSIONS: We developed a test to identify drugs that cause liver injury in patients based on their toxicity to MH cells isolated from patients with DILI. We validated results from the assay and found it to identify drugs that cause DILI with 92.3% sensitivity and 100% specificity. The MH cell test could be a tool to identify causes of iDILI, even in patients taking multiple medications. ClinicalTrials.gov no: NCT 02353455.

Predictors of health-related quality of life in maltreated children and adolescents.

PURPOSE: Research on the consequences of child maltreatment has primarily focused on behavior and mental health; the children's overall well-being has not received the same attention. A number of studies have investigated health-related quality of life (HRQoL) among victims of child maltreatment, but there is still a lack of knowledge about predictors of HRQoL in maltreated children and adolescents. This study seeks to bridge the gap by drawing data from the German multi-site study Child Abuse and Neglect Case-Management (CANMANAGE). METHODS: Parents or caregivers of 350 children and adolescents completed a proxy version of the Kidscreen-10-Index, a multidimensional instrument measuring child HRQoL. An additional 249 children age 8 years and older completed a self-report version. Multiple regression analyses were performed to identify potential predictors for both self- and proxy-rated HRQoL. RESULTS: Comparisons with the reference group revealed a significantly lower mean proxy-rated HRQoL, the self-rated HRQoL of the study sample was not significantly impaired. Predictors of impaired self-reported HRQoL were older age, self-reported posttraumatic stress symptoms (PTSS), and self-reported emotional and behavioral symptoms. Predictors of impaired proxy-reported HRQoL again were older age, self-reported PTSS, and emotional and behavioral symptoms in the child/adolescent, as reported by the caregiver, as well as low socioeconomic status. Multivariate analysis explained 20% and 38% of the variability in self-reported and proxy-rated HRQoL, respectively. CONCLUSIONS: It is important to treat PTSS and emotional and behavioral symptoms in maltreated children, as these two phenomena are strong cross-sectional predictors of a child's HRQoL. Trauma-focused cognitive behavioral therapies are one possible option to address the needs of such children.

[Drug-induced autoimmune-like liver injury]. / Arzneimittelinduzierte immunvermittelte Leberschädigung.

Drug-induced liver injury (DILI) is a rare yet potentially life-threatening disease. Besides intrinsic DILI, which is mainly caused by paracetamol overdosing and which is dose-dependent and predictable, there is idiosyncratic DILI-an unpredictable and dose-independent injury of the liver caused by certain medications that only occurs in a minority of patients taking this drug. The reason why some patients react with DILI towards a specific drug is still unknown. However, the immune system plays a central role, which is underlined by the association of certain human leukocyte antigen (HLA) polymorphisms and DILI caused by specific drug classes. Due to the immunological processes that lead to the liver injury in DILI, there are great overlaps regarding laboratory and histological parameters between DILI and autoimmune hepatitis (AIH). Differentiating DILI and AIH can therefore be challenging, especially at the time of presentation. In addition, there are other immunologically mediated DILI phenotypes, in particular the newly defined drug-induced autoimmune-like hepatitis (DI-ALH) and liver injuries caused by checkpoint inhibitors (CPI). DI-ALH is characterized by autoimmune features and good responses towards corticosteroids, with the difference that DI-ALH mostly does not relapse after discontinuation of corticosteroids. CPI-induced liver injury has become more frequent with the rising use of those drugs and is characterized by a distinct histopathological pattern with granulomatous hepatitis and infiltration dominated by cytotoxic T cells. Similarly, the recently recognized liver injury following vaccinations also shows an autoimmune phenotype; however, in contrast to AIH, cytotoxic T cells seem to dominate the inflammatory infiltrates in the liver.

Pharmacodynamic Effect of mTOR Inhibition-based Immunosuppressive Therapy on T- and B-cell Subsets After Renal Transplantation.

Background: The mammalian target of rapamycin inhibitor (mTORi) therapy after kidney transplantation is solely monitored pharmacokinetically, not necessarily reflecting PI3K-Akt-mTOR pathway blockade efficacy leading to potential under-or overimmunosuppression. Methods: In this cross-sectional study, phosphoflow cytometry was used to determine the efficacy of mTOR inhibition in peripheral T- and B-lymphocyte subsets by assessing p70S6 kinase (p70S6K) phosphorylation in renal transplant recipients upon treatment with a combination of either mTORi and calcineurin inhibitors (n = 18), or mTORi with mycophenolic acid (n = 9). Nine dialysis patients with end-stage renal disease and 17 healthy age-matched volunteers served as controls. Results: mTORi treatment reduced p70S6K phosphorylation in CD4+, CD8+ T, and CD19+ B cells compared with healthy controls (HCs). Subpopulation analysis of CD4+ T cells and CD19+ B cells revealed a significant reduction of p70S6K phosphorylation in CD4+CD45RA-CD25- Th cells (P < 0.05), CD24hiCD38hi transitional B cells (P < 0.001), CD24+CD38- memory B cells (P < 0.001), and CD24intCD38int-naive B cells (P < 0.05) upon mTORi treatment, whereas CD4+CD45RA-CD25++CD127- regulatory T cells and CD24-CD38hi plasmablasts were not affected. Compared with mTORi + mycophenolic acid therapy, mTORi + calcineurin inhibitor treatment exhibited an even stronger inhibition of p70S6K phosphorylation in CD4+CD45RA-CD25- Th cells and CD8+ T cells. However, trough levels of mTORi did not correlate with p70S6K phosphorylation. Conclusions: mTORi selectively inhibited p70S6K phosphorylation in select lymphocyte subtypes. Assessing p70S6K phosphorylation by phosphoflow cytometry may serve as an approach to understand cell subset specific effects of mTORi providing detailed pharmacodynamic information for individualizing immunosuppression.