Reproducibility of the Oxford classification of immunoglobulin A nephropathy, impact of biopsy scoring on treatment allocation and clinical relevance of disagreements: evidence from the VALidation of IGA study cohort.

BACKGROUND: The VALidation of IGA (VALIGA) study investigated the utility of the Oxford Classification of immunoglobulin A nephropathy (IgAN) in 1147 patients from 13 European countries. Methods. Biopsies were scored by local pathologists followed by central review in Oxford. We had two distinct objectives: to assess how closely pathology findings were associated with the decision to give corticosteroid/immunosuppressive (CS/IS) treatments, and to determine the impact of differences in MEST-C scoring between central and local pathologists on the clinical value of the Oxford Classification. We tested for each lesion the associations between the type of agreement (local and central pathologists scoring absent, local present and central absent, local absent and central present, both scoring present) with the initial clinical assessment, as well as long-term outcomes in those patients who did not receive CS/IS. RESULTS: All glomerular lesions (M, E, C and S) assessed by local pathologists were independently associated with the decision to administer CS/IS therapy, while the severity of tubulointerstitial lesions was not. Reproducibility between local and central pathologists was moderate for S (segmental sclerosis) and T (tubular atrophy/interstitial fibrosis), and poor for M (mesangial hypercellularity), E (endocapillary hypercellularity) and C (crescents). Local pathologists found statistically more of each lesion, except for the S lesion, which was more frequent with central review. Disagreements were more likely to occur when the proportion of glomeruli affected was low. The M lesion, assessed by central pathologists, correlated better with the severity of the disease at presentation and discriminated better with outcomes. In contrast, the E lesion, evaluated by local pathologists, correlated better with the clinical presentation and outcomes when compared with central review. Both C and S lesions, when discordant between local and central pathologists, had a clinical phenotype intermediate to double absent lesions (milder disease) and double present (more severe). CONCLUSION: We conclude that differences in the scoring of MEST-C criteria between local pathologists and a central reviewer have a significant impact on the prognostic value of the Oxford Classification. Since the decision to offer immunosuppressive therapy in this cohort was intimately associated with the MEST-C score, this study indicates a need for a more detailed guidance for pathologists in the scoring of IgAN biopsies.

High pretransplant serum levels of CXCL9 are associated with increased risk of acute rejection and graft failure in kidney graft recipients.

Several clinical and experimental models have underlined the role of the CXCR3-binding chemokines in the immune-mediated kidney diseases. This study aimed to investigate the predictive value of measuring pretransplant CXCL9 levels for acute rejection (AR) onset and kidney transplantation outcome. Pretransplantation serum levels of CXCL9 were tested retrospectively in 252 kidney graft recipients, whose stratification in two groups according to CXCL9 levels (<272.1 pg/ml vs. >272.1 pg/ml) showed highly significant differences in 5-year survival rates (97.7% vs. 73.3%; P < 0.001). Multivariate analysis demonstrated that among the analysed variables, CXCL9 [relative risk (RR) 11.708] and AR (RR 3.604) had the highest predictive power of graft loss. Accordingly, patients with AR (254.4 + or - 22.1; P < 0.05) and, even more, those with anti-thymoglobulin (ATG)-treated AR also showed increased pretransplant serum CXCL9 levels (319.3 + or - 28.1, P < 0.001). Moreover, CXCL9 expression and distribution were investigated in tissue specimens obtained from 10 patients affected by AR, and wide CXCL9 expression was detected not only in infiltrating inflammatory cells but also in vascular and tubular structures. Measurement of pretransplant serum CXCL9 levels might represent the tracking of a clinically useful parameter to identify subjects at high risk of AR and graft failure. These findings might be used for the individualization of immunosuppressive therapies.

[Immunogical surveillance and oncogenesis: role of proliferation signal inhibitors]. / Sorveglianza immunologica ed oncogenesi: ruolo degli inibitori del segnale di proliferazione.

The authors review the antineoplastic effect of mTOR inhibitors and their biological basis. In normal cells mTOR is an intracellular serine/threonine kinase that is a central controller of cell growth and proliferation. mTOR integrates signals from a variety of sources as nutrients and growth factors. mTOR regulation can affect angiogenesis, cell growth, nutrient uptake and utilization, and metabolism. Growth factors such as insulin growth factor (IGF), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and vascular endothelial growth factor (VEGF) bind to and activate receptors located on the cell surface. Receptors activate intracellular signaling cascades through PI3K-AKT-mTOR (phosphatidylinositol 3-kinase/serine-threonine kinase-mTOR), leading to protein synthesis. As a consequence, activation of the mTOR pathway is linked to increased protein synthesis by modulating elements that are important in a number of cellular processes, including growth, proliferation, angiogenesis, and nutrient uptake. Deregulation of mTOR-linked pathways increases the risk of developing cancer and has been identified in many human cancer types. Such deregulation includes overexpression of growth factors, overexpression or mutations of growth factor receptors, loss of tumor suppressor genes, and gain-of-function mutations in mTOR-linked pathways. These changes permit the survival, growth, proliferation, and migration of cancer cells and promote tumor angiogenesis. Targeting them has been a successful anticancer strategy. Targeting mTOR as well as these deregulated pathways could provide enhanced anticancer activity. The efficacy of mTOR inhibitors in preventing several types of cancer in transplanted patients, or making them regress once developed, has been documented in clinical trials and case reports.

Risk and Protective Factors for Gastrointestinal Symptoms associated with Antibiotic Treatment in Children: A Population Study.

PURPOSE: Gastrointestinal symptoms are often related to antibiotic treatment. Their incidence, risk and protective conditions in children are not well defined and represent the aims of this study. METHODS: We prospectively enrolled inpatient children submitted to antibiotic treatment. Indication, type, dose and duration of treatment, probiotic supplementation and gastrointestinal symptoms were recorded at recruitment, after two and four weeks. Antibiotic-associated diarrhea (AAD) was defined as the presence of at least 3 loose/liquid stools within 14 days from antibiotic onset. RESULTS: AAD occurred in 59/289 (20.4%) of patients, with increased risk in children younger than 3 years (relative risk [RR]=4.25), in lower respiratory (RR=2.11) and urinary infections (RR=3.67), intravenous administration (RR=1.81) and previous AAD episodes (RR=1.87). Abdominal pain occurred in 27/289 (9.3%), particularly in children >6 years (RR=4.15), with previous abdominal pain (RR=7.2) or constipation (RR=4.06). Constipation was recorded in 23/289 (8.0%), with increased risk in children having surgery (RR=2.56) or previous constipation (RR=7.38). Probiotic supplementation significantly reduced AAD (RR=0.30) and abdominal pain (RR=0.36). Lactobacillus rhamnosus GG (LGG) and L. reuteri significantly reduced AAD (RR=0.37 and 0.35) and abdominal pain (RR=0.37 and 0.24). CONCLUSION: AAD occurred in 20.4% of children, with increased risk at younger age, lower respiratory and urinary tract infections, intravenous treatment and previous AAD. LGG and L. reuteri reduced both AAD and associated abdominal pain.

Antineoplastic effect of proliferation signal inhibitors: from biology to clinical application.

The authors review the antineoplastic effect of mammalian target of rapamycin (mTOR) inhibitors and their biological basis. mTOR is an intracellular serine/threonine kinase that is a central controller of cell growth and proliferation. mTOR integrates signals from sources such as nutrients and growth factors. mTOR regulation can affect angiogenesis, cell growth, nutrient uptake and utilization, and metabolism. Growth factors such as insulin growth factor, epidermal growth factor, platelet-derived growth factor and vascular endothelial growth factor bind to and activate receptors located on the cell surface. Receptors activate intracellular signaling cascades phosphatidylinositol 3 kinase-serine-threonine kinase-mTOR (PI3K-AKT-mTOR) leading to protein synthesis. Activation of the mTOR pathway is linked to increased protein synthesis by modulating elements that are important in cellular processes, including growth, proliferation, angiogenesis and nutrient uptake. Many growth factor receptors and signaling pathway components are deregulated in cancer. Deregulations in mTOR-linked pathways increase the risk of developing cancer or have been identified in many human cancers. Deregulations include overexpression of growth factors, overexpression or mutations of growth factor receptors, loss of tumor suppressor genes, and gain-of-function mutations in mTOR-linked pathways. These deregulations permit the survival, growth, proliferation and migration of cancer cells and promote tumor angiogenesis. Targeting them has been a successful anticancer strategy. Targeting mTOR as well as these deregulated pathways could provide enhanced anticancer activity. The efficacy of mTOR inhibitors in preventing several types of cancers in transplanted patients or in recovering cancers developed in transplant patients has been documented in both trials and single reports.

[Preemptive living donor kidney transplant]. / Il trapianto pre-emptive da donatore vivente.

We analyze and describe the epidemiology, characteristics and outcome of patients who underwent preemptive kidney transplants from living donors. The outcome of preemptive transplants from deceased donors and that of living donor transplants in patients who have started dialysis are often compared with the outcome of preemptive transplants from living donors. The causes of the better outcome of preemptive kidney transplants are analyzed here. We have examined data from large registries including the Collaborative Transplant Study, USRDS and ANZDATA registry as well as the results of single-center studies and data from developing countries. Overall, preemptive transplantation is more frequently performed with living donors. Recipients are often younger and have fewer vascular comorbidities. Also late referrals are less frequent with preemptive kidney transplantation. The data described by different studies may be discordant, but this is caused by different factors linked to the studies, as well as donor type, recipient age and residual renal function at transplant. Preemptive transplant usually has a better outcome because of the avoidance of dialysis-related comorbidities. Preemptive transplant is associated with less delayed graft function, fewer acute rejections, and better graft and patient survival rates.

Testing the Cow's Milk-Related Symptom Score (CoMiSSTM) for the Response to a Cow's Milk-Free Diet in Infants: A Prospective Study.

The diagnosis of cow's milk allergy (CMA) is particularly challenging in infants, especially with non-Immunoglobulin E (IgE)-mediated manifestations, and inaccurate diagnosis may lead to unnecessary dietary restrictions. The aim of this study was to assess the accuracy of the cow's milk-related symptom score (CoMiSSTM) in response to a cow's milk-free diet (CMFD). We prospectively recruited 47 infants (median age three months) who had been placed on a CMFD due to persisting unexplained gastrointestinal symptoms. We compared data with 94 healthy controls (median age three months). The CoMiSSTM score was completed at recruitment and while on the exclusion diet. In 19/47 (40%) cases a response to the diet occurred. At recruitment CoMiSSTM was significantly higher in cases compared to controls (median score 8 vs. 3; p-value: <0.05), 9 cases had a score ≥12 and 8/9 normalized on CMFD. An oral milk challenge was performed in all 19 responders and six of these had a positive reaction to cow's milk (CM). In eight infants IgE allergy tests were positive. The receiver operation characteristic (ROC) curve identified a CoMISSTM score of 9 to be the best cut-off value (84% sensitivity, 85% specificity, 80% positive (PPV) and 88% negative predictive value (NPV)) for the response to CMFD. We found CoMiSSTM to be a useful tool to help identify infants with persisting gastrointestinal symptoms and suspected CMA that would benefit from CMFD.

Estimated one-year glomerular filtration rate is the best predictor of long-term graft function following renal transplant.

BACKGROUND: Long-term success of renal transplantation depends upon the quality of the donor organ, avoidance of peritransplant and early posttransplant damage (rejection), and optimal maintenance of graft function after the first 6-12 months. Glomerular filtration rate (GFR) at 1 year is a standard way to evaluate short-term success, whereas calculated GFR at 5 years gives a better appreciation of long-term outcomes. The objective of this study was to assess the effect of various demographic and transplant-related parameters on renal function via GFR at 1 year and 5 years post transplantation, using univariate and multivariate data analysis. METHODS: Data on 1-year GFR were available from 10,397 patients, whereas 2,889 patients provided data on both 1-year and 5-year GFR. All patients were enrolled in the Neoral Multinational Observational Study in Transplantation (Neoral-MOST), an ongoing, prospective, observational study of adult renal transplant recipients. RESULTS: One-year GFR was the most relevant predictor for 5-year GFR. In a multifactorial analysis (ANCOVA) using 1-year GFR as a continuous variable, the effects of several highly relevant parameters from univariate analysis (such as acute rejection and delayed graft function) on 5-year GFR appeared to be fully mediated by their influence on 1-year GFR, whereas immunological risk factors like HLA match or previous transplantation had an ongoing effect on graft function beyond year 1. CONCLUSIONS: The findings of this study corroborate and augment data from previous registry surveys, and confirm the importance of observational studies in investigating the role of peritransplant parameters on long-term graft outcome.

Complement related kidney diseases: Recurrence after transplantation.

The recurrence of renal disease after renal transplantation is becoming one of the main causes of graft loss after kidney transplantation. This principally concerns some of the original diseases as the atypical hemolytic uremic syndrome (HUS), the membranoproliferative glomerulonephritis (MPGN), in particular the MPGN now called C3 glomerulopathy. Both this groups of renal diseases are characterized by congenital (genetic) or acquired (auto-antibodies) modifications of the alternative pathway of complement. These abnormalities often remain after transplantation because they are constitutional and poorly influenced by the immunosuppression. This fact justifies the high recurrence rate of these diseases. Early diagnosis of recurrence is essential for an optimal therapeutically approach, whenever possible. Patients affected by end stage renal disease due to C3 glomerulopathies or to atypical HUS, may be transplanted with extreme caution. Living donor donation from relatives is not recommended because members of the same family may be affected by the same gene mutation. Different therapeutically approaches have been attempted either for recurrence prevention and treatment. The most promising approach is represented by complement inhibitors. Eculizumab, a monoclonal antibody against C5 convertase is the most promising drug, even if to date is not known how long the therapy should be continued and which are the best dosing. These facts face the high costs of the treatment. Eculizumab resistant patients have been described. They could benefit by a C3 convertase inhibitor, but this class of drugs is by now the object of randomized controlled trials.

High rate of recurrence in renal transplant recipients after a first episode of venous thromboembolism.

BACKGROUND: No data are available about the optimal duration of oral anticoagulant therapy (OAT) after an episode of venous thromboembolism (VTE) occurring in renal transplant (RT) recipients. Our study was undertaken to evaluate the risk of VTE recurrence in patients developing a first episode of VTE after RT. METHODS: Among 484 RT patients, 34 (7%) developed a first VTE: 28/34 VTE patients (Group 1) were prospectively studied, after stopping OAT. Group 1 was compared with a group of 84 patients without history of renal disease who had suffered from a first episode of VTE matched for age, sex and type of thrombotic event (Group 2) and with a matched group of 84 RT recipients with no history of VTE (Group 3). After OAT withdrawal, blood samples were obtained for thrombophilia and clotting activation markers (prothrombin fragment 1+2 (F1+2) and D-dimer plasma levels). RESULTS: During follow-up, 14/28 patients of Group 1 and 8/84 patients of Group 2 experienced VTE recurrence (P < 0.0005). Homocysteine, F1+2 and D-dimer plasma levels were significantly higher in Group 1 than in Group 2 and 3 (P < 0.0001 and <0.05 respectively) for all the three parameters. CONCLUSIONS: Our data outline the high risk of VTE recurrence in RT recipients. Strategies for VTE recurrence prevention are needed; Prolonged OAT, in spite of the high bleeding risk of RT patients, should be considered in this respect.

High CXCL10 expression in rejected kidneys and predictive role of pretransplant serum CXCL10 for acute rejection and chronic allograft nephropathy.

BACKGROUND: Several experimental models have shown that CXCL10 is required for initiation and development of graft failure caused by both acute and chronic rejection. METHODS: CXCL10 expression and distribution was investigated in tissue specimens obtained from 22 patients suffering from acute rejection (AR) or chronic allograft nephropathy (CAN) by using in situ hybridization. Furthermore, pretransplantation sera of 316 cadaveric kidney-graft recipients were tested retrospectively for serum CXCL10 levels by a quantitative sandwich immunoassay. RESULTS: Bioptic specimens obtained from patients with CAN were characterized by wide CXCL10 expression not only at level of infiltrating inflammatory cells but also of vascular, tubular, and glomerular structures. In addition, assessment of pretransplant serum CXCL10 levels in 316 graft recipients and stratification of patients in three groups according to serum CXCL10 levels (<100 pg/mL, n=163; 100-150 pg/mL, n=69; >150 pg/mL, n=84) showed highly significant differences in 5-year survival rates for the two extreme groups (95.7% vs. 79.7%, P=0.0002). Accordingly, patients who developed severe, early AR (277.14+/-65.08 p=0.004) and those who developed CAN also showed increased pretransplant serum CXCL10 levels (193.2+/-36.9, P=0.03). Multivariate analysis demonstrated that among the analyzed variables, CXCL10 (relative risk [RR] 2.801) and delayed graft function (RR 3.728) had the highest predictive power of graft loss. CONCLUSIONS: These results suggest that pretransplant serum CXCL10 levels greater than 150 pg/mL confer an increased risk of early, severe, AR and subsequent CAN, finally resulting in renal-allograft failure. This finding might be used for the individualization of immunosuppressive therapies.

Complement involvement in kidney diseases: From physiopathology to therapeutical targeting.

Complement cascade is involved in several renal diseases and in renal transplantation. The different components of the complement cascade might represent an optimal target for innovative therapies. In the first section of the paper the authors review the physiopathology of complement involvement in renal diseases and transplantation. In some cases this led to a reclassification of renal diseases moving from a histopathological to a physiopathological classification. The principal issues afforded are: renal diseases with complement over activation, renal diseases with complement dysregulation, progression of renal diseases and renal transplantation. In the second section the authors discuss the several complement components that could represent a therapeutic target. Even if only the anti C5 monoclonal antibody is on the market, many targets as C1, C3, C5a and C5aR are the object of national or international trials. In addition, many molecules proved to be effective in vitro or in preclinical trials and are waiting to move to human trials in the future.

Update on ischemia-reperfusion injury in kidney transplantation: Pathogenesis and treatment.

Ischemia/reperfusion injury is an unavoidable relevant consequence after kidney transplantation and influences short term as well as long-term graft outcome. Clinically ischemia/reperfusion injury is associated with delayed graft function, graft rejection, chronic rejection and chronic graft dysfunction. Ischemia/reperfusion affects many regulatory systems at the cellular level as well as in the renal tissue that result in a distinct inflammatory reaction of the kidney graft. Underlying factors of ischemia reperfusion include energy metabolism, cellular changes of the mitochondria and cellular membranes, initiation of different forms of cell death-like apoptosis and necrosis together with a recently discovered mixed form termed necroptosis. Chemokines and cytokines together with other factors promote the inflammatory response leading to activation of the innate immune system as well as the adaptive immune system. If the inflammatory reaction continues within the graft tissue, a progressive interstitial fibrosis develops that impacts long-term graft outcome. It is of particular importance in kidney transplantation to understand the underlying mechanisms and effects of ischemia/reperfusion on the graft as this knowledge also opens strategies to prevent or treat ischemia/reperfusion injury after transplantation in order to improve graft outcome.

Vitamin supplementation reduces the progression of atherosclerosis in hyperhomocysteinemic renal-transplant recipients.

BACKGROUND: We previously demonstrated among renal-transplant recipients (RTRs) a high prevalence of hyperhomocysteinemia, which might account for their elevated cardiovascular risk. The purpose of our study was to document, in hyperhomocysteinemic RTRs, the effect of vitamin supplementation on carotid intima-media thickness (cIMT), which is an early sign of atherosclerosis. METHODS: A total of 56 stable hyperhomocysteinemic RTRs were randomly assigned to vitamin supplementation (folic acid 5 mg/day; vitamin B(6) 50 mg/day; vitamin B(12) 400 microg) (group A) or placebo treatment (group B) for 6 months. All subjects underwent cardiovascular risk-factor assessment, including fasting homocysteine (Hcy) levels assay, and high resolution B-mode ultrasound to measure the intima-media thickness of common carotid arteries, at time of enrollment and after 6 months. RESULTS: Fasting Hcy levels markedly decreased in group A after treatment (21.8 [15.5-76.6] micromol/L vs. 9.3 [5.8-13] micromol/L; P<0.0001), whereas no significant changes were observed in group B (20.5 [17-37.6] micromol/L vs. 20.7 [15-34] micromol/L; P=not significant). In group A, cIMT significantly decreased after treatment (0.95+/-0.20 mm vs. 0.64+/-0.17 mm; P<0.0001). All except one patient showed a reduction of cIMT and the mean percentage of cIMT decrease was -32.2+/-12.9%. Patients with methylenetetrahydrofolate reductase (MTHFR) C677T +/+ genotype, with higher Hcy levels, had the major percentage of decrease of Hcy with respect to the other genotypes (mean decrease: MTHFR +/+ 74.8+/-5.7%; MTHFR +/- 58.1+/-10%; MTHFR -/- 56.3+/-8.6%). In hyperhomocysteinemic patients without vitamin supplementation (group B) we documented a significant increase in cIMT after 6 months (0.71+/-0.16 mm vs. 0.87+/-0.19 mm; P<0.05). In 19 of 28 subjects we observed an increase in cIMT, and in 9 of 28 the cIMT was unmodified. The mean percentage of cIMT increase was + 23.3+/-21.1%. CONCLUSIONS: Our results demonstrate a beneficial effect of the treatment of hyperhomocysteinemia by vitamin supplementation on cIMT in a group of RTRs.

Post-transplant diabetes mellitus.

Post-transplant diabetes mellitus (PTDM) is a frequent and serious complication after kidney transplantation. Its ethiopathogenesis is multifactorial and includes the immunosuppressive regimen, the ethnicity, older age and the body mass index. Among these, calcineurine inhibitor and steroid use seems to have outstanding relevance. Both patient and graft survival is significantly reduced in recipients affected by PTDM. The main clinical aspects of transplant recipients with PTDM are patient and graft survival rate, infections, cardiovascular complications and late complications of diabetes that include nephropathy, neuropathy, retinopathy, micro-macroangiopathy and bone disease. The main stages of PTDM prophylaxis and treatment are: to identify patients at risk pre-transplantation; to control modifiable risk factors post-transplantation; to control hypertension and lipid profiles and a strict metabolic control. Insulin treatment is indicated mainly in thin patients and oral hypoglycemic agents should be reserved for overweight patients. Transplant centers are currently accepting higher risk candidates for post-transplant complications; therefore, attention needs to shift to the prevention and the control of complications, such as PTDM, because they can lead to a poor quality of life and an increased mortality in patients with functioning grafts.

Impact of donor-specific antibodies on the outcomes of kidney graft: Pathophysiology, clinical, therapy.

Allo-antibodies, particularly when donor specific, are one of the most important factors that cause both early and late graft dysfunction. The authors review the current state of the art concerning this important issue in renal transplantation. Many antibodies have been recognized as mediators of renal injury. In particular donor-specific-Human Leukocyte Antigens antibodies appear to play a major role. New techniques, such as solid phase techniques and Luminex, have revealed these antibodies from patient sera. Other new techniques have uncovered alloantibodies and signs of complement activation in renal biopsy specimens. It has been acknowledged that the old concept of chronic renal injury caused by calcineurine inhibitors toxicity should be replaced in many cases by alloantibodies acting against the graft. In addition, the number of patients on waiting lists with preformed anti-human leukocyte antigens (HLA) antibodies is increasing, primarily from patients with a history of renal transplant failure already been sensitized. We should distinguish early and late acute antibody-mediated rejection from chronic antibody-mediated rejection. The latter often manifets late during the course of the post-transplant period and may be difficult to recognize if specific techniques are not applied. Different therapeutic strategies are used to control antibody-induced damage. These strategies may be applied prior to transplantation or, in the case of acute antibody-mediated rejection, after transplantation. Many new drugs are appearing at the horizon; however, these drugs are far from the clinic because they are in phase I-II of clinical trials. Thus the pipeline for the near future appears almost empty.

What's new in clinical solid organ transplantation by 2013.

Innovative and exciting advances in the clinical science in solid organ transplantation continuously realize as the results of studies, clinical trials, international conferences, consensus conferences, new technologies and discoveries. This review will address to the full spectrum of news in transplantation, that verified by 2013. The key areas covered are the transplantation activity, with particular regards to the donors, the news for solid organs such as kidney, pancreas, liver, heart and lung, the news in immunosuppressive therapies, the news in the field of tolerance and some of the main complications following transplantation as infections and cancers. The period of time covered by the study starts from the international meetings held in 2012, whose results were published in 2013, up to the 2013 meetings, conferences and consensus published in the first months of 2014. In particular for every organ, the trends in numbers and survival have been reviewed as well as the most relevant problems such as organ preservation, ischemia reperfusion injuries, and rejections with particular regards to the antibody mediated rejection that involves all solid organs. The new drugs and strategies applied in organ transplantation have been divided into new way of using old drugs or strategies and drugs new not yet on the market, but on phase Ito III of clinical studies and trials.

Is it time to give up with calcineurin inhibitors in kidney transplantation?

Calcineurin inhibitors (CNIs) represent today a cornerstone for the maintenance immunosuppressive treatment in solid organ transplantation. Nevertheless, several attempts have been made either to minimize their dosage or to avoid CNIs at all because these drugs have the severe side effect of chronic nephrotoxicity. This issue represents a frontier for renal transplantation. The principal problem is to understanding whether the poor outcome over the long-term may be ascribed to CNIs nephrotoxicity or to the inability of these drugs to control the acute and chronic rejection B cells mediated. The authors analyze extensively all the international trials attempting to withdraw, minimize or avoid the use of CNIs. Few trials undertaken in low risk patients with an early conversion from CNIs to proliferation signal inhibitors were successful, but the vast majority of trials failed to improve CNIs side effects. To date the use of a new drug, a co-stimulation blocker, seems promising in avoiding CNIs with similar efficacy, better glomerular filtration rate and an improved metabolic profile. Moreover the use of this drug is not associated with the development of donor-specific anti-human leukocyte antigen antibodies. This point has a particular relevance, because the failure of CNIs to realize good outcomes in renal transplantation has recently ascribed to their inability to control the acute and chronic rejections B-cell mediated. This paper analyzes all the recent studies that have been done on this issue that represents the real frontier that should be overcome to realize better results over the long-term after transplantation.

Update on hemolytic uremic syndrome: Diagnostic and therapeutic recommendations.

Hemolytic uremic syndrome (HUS) is a rare disease. In this work the authors review the recent findings on HUS, considering the different etiologic and pathogenetic classifications. New findings in genetics and, in particular, mutations of genes that encode the complement-regulatory proteins have improved our understanding of atypical HUS. Similarly, the complement proteins are clearly involved in all types of thrombotic microangiopathy: typical HUS, atypical HUS and thrombotic thrombocytopenic purpura (TTP). Furthermore, several secondary HUS appear to be related to abnormalities in complement genes in predisposed patients. The authors highlight the therapeutic aspects of this rare disease, examining both "traditional therapy" (including plasma therapy, kidney and kidney-liver transplantation) and "new therapies". The latter include anti-Shiga-toxin antibodies and anti-C5 monoclonal antibody "eculizumab". Eculizumab has been recently launched for the treatment of the atypical HUS, but it appears to be effective in the treatment of typical HUS and in TTP. Future therapies are in phases I and II. They include anti-C5 antibodies, which are more purified, less immunogenic and absorbed orally and, anti-C3 antibodies, which are more powerful, but potentially less safe. Additionally, infusions of recombinant complement-regulatory proteins are a potential future therapy.