Targeted therapy for capillary-venous malformations.

Sporadic venous malformations are genetic conditions primarily caused by somatic gain-of-function mutation of PIK3CA or TEK, an endothelial transmembrane receptor signaling through PIK3CA. Venous malformations are associated with pain, bleedings, thrombosis, pulmonary embolism, esthetic deformities and, in severe cases, life-threatening situations. No authorized medical treatment exists for patients with venous malformations.

Use of a Belatacept-based Immunosuppression for Kidney Transplantation From Donors After Circulatory Death: A Paired Kidney Analysis.

Background: Efficacy and safety of belatacept have not been specifically reported for kidney transplantations from donors after circulatory death.

Methods: In this retrospective multicenter paired kidney study, we compared the outcome of kidney transplantations with a belatacept-based to a calcineurin inhibitor (CNI)-based immunosuppression. We included all kidney transplant recipients from donors after uncontrolled or controlled circulatory death performed in our center between February 2015 and October 2020 and treated with belatacept (n = 31).

COVID-19 early curative treatments in kidney transplant recipients: is it really reasonable at the Omicron era?

Objective: Data about efficacy and safety of the latest COVID-19 treatments as nirmatrelvir/ritonavir (n/r) or Sotrovimab is scarce in solid organ transplant recipients in the Omicron era. This study aims at describing the outcome of kidney transplant recipients (KTRs) presenting Omicron infection according to their management: n/r, sotrovimab or no specific treatment.

Patients And Methods: We conducted a monocentric, retrospective observational study, including KTRs diagnosed Omicron infection between January and May 1st 2022 and compared their outcome (primary outcome defined as hospital admission for COVID-19 within a month after symptoms onset) according to early COVID-19 management.

Nonskeletal and skeletal effects of high doses versus low doses of vitamin D in renal transplant recipients: Results of the VITALE (VITamin D supplementation in renAL transplant recipients) study, a randomized clinical trial.

Vitamin D sufficiency is associated with a reduced risk of fractures, diabetes mellitus, cardiovascular events, and cancers, which are frequent complications after renal transplantation. The VITALE (VITamin D supplementation in renAL transplant recipients) study is a multicenter double-blind randomized trial, including nondiabetic adult renal transplant recipients with serum 25-hydroxy vitamin D (25(OH) vitamin D) levels of <30 ng/mL, which is randomized 12 to 48 months after transplantation to receive high (100 000 IU) or low doses (12 000 IU) of cholecalciferol every 2 weeks for 2 months and then monthly for 22 months. The primary outcome was a composite endpoint, including diabetes mellitus, major cardiovascular events, cancer, and death.

Distinct immunopathological mechanisms of EBV-positive and EBV-negative posttransplant lymphoproliferative disorders.

EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013-2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50).

COVID-19-associated collapsing glomerulopathy: a report of two cases and literature review.

Nephrotic range proteinuria has been reported during the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease (COVID-19). However, the pathological mechanisms underlying this manifestation are unknown. In this article, we present two cases of collapsing glomerulopathy (CG) associated with acute tubular necrosis during the course of COVID-19, and review the literature for similar reports.

Predictive value of mixed antigen screen beads in pre-transplant assessment of HLA immunization in solid organ transplant recipients.

Pre-transplant serum screening of anti-HLA antibodies is recommended for solid organ transplantations. Many laboratories use the less expensive bead-based screening assay as the main technique and, if positive, turn to single-antigen beads (SAB). We studied the correlations between these two immunoassays.

Skewed T cell responses to Epstein-Barr virus in long-term asymptomatic kidney transplant recipients.

Kidney transplant recipients (KTRs) abnormally replicate the Epstein Barr Virus (EBV). To better understand how long-term immunosuppression impacts the immune control of this EBV re-emergence, we systematically compared 10 clinically stable KTRs to 30 healthy controls (HCs). The EBV-specific T cell responses were determined in both groups by multiparameter flow cytometry with intra cellular cytokine staining (KTRs n = 10; HCs n = 15) and ELISpot-IFNγ assays (KTRs n = 7; HCs n = 7).

Use of Highly Individualized Complement Blockade Has Revolutionized Clinical Outcomes after Kidney Transplantation and Renal Epidemiology of Atypical Hemolytic Uremic Syndrome.

Background: Atypical hemolytic uremic syndrome (HUS) is associated with high recurrence rates after kidney transplant, with devastating outcomes. In late 2011, experts in France recommended the use of highly individualized complement blockade-based prophylaxis with eculizumab to prevent post-transplant atypical HUS recurrence throughout the country.

Methods: To evaluate this strategy's effect on kidney transplant prognosis, we conducted a retrospective multicenter study from a large French nationwide registry, enrolling all adult patients with atypical HUS who had undergone complement analysis and a kidney transplant since January 1, 2007.

Early Acute Microvascular Kidney Transplant Rejection in the Absence of Anti-HLA Antibodies Is Associated with Preformed IgG Antibodies against Diverse Glomerular Endothelial Cell Antigens.

Background: Although anti-HLA antibodies (Abs) cause most antibody-mediated rejections of renal allografts, non-anti-HLA Abs have also been postulated to contribute. A better understanding of such Abs in rejection is needed.

Methods: We conducted a nationwide study to identify kidney transplant recipients without anti-HLA donor-specific Abs who experienced acute graft dysfunction within 3 months after transplantation and showed evidence of microvascular injury, called acute microvascular rejection (AMVR).

Outcome of second kidney transplantation in patients with previous post-transplantation Kaposi's sarcoma: A French retrospective study.

This retrospective study concerned 8 patients with post-transplantation Kaposi's sarcoma (pt-KS) after a first kidney transplant who later had a second kidney transplantation. Pt-KS was widespread, with lymph node or visceral involvement in 7 cases. Complete remission was observed in 6 cases and partial remission in 2.

Invasive cutaneous Neoscytalidium infections in renal transplant recipients: a series of five cases.

Background: Neoscytalidium species (formerly Scytalidium species) are black fungi that usually cause cutaneous infections mimicking dermatophytes lesions. Very few publications have reported invasive or disseminated infections.

Case Presentation: In this paper, we report the clinical presentations, treatments and outcomes of five cases of invasive Neoscytalidium infections with cutaneous involvement, including two cases with disseminated infection, in five renal transplant recipients.

Gynecologic follow up of 129 women on dialysis and after kidney transplantation: a retrospective cohort study.

Objective: To describe the gynecologic issues and follow-up in our referral center of women on dialysis and after kidney transplantation.

Study Design: This retrospective cohort study included 129 dialysed women among whom 102 had had transplants. Data on menstrual pattern, pregnancies, contraception, and cervical cytology were retrieved from patients' files.

Costimulation blockade and its possible future use in clinical transplantation.

The nonimmune effects of currently used immunosuppressive drugs result in a high incidence of late graft loss due to nephrotoxicity and death of patients. As an immune-specific alternative to conventional immunosuppressants, new biotechnology tools can be used to block the costimulation signals of T-cell activation. Many experimental studies--particularly preclinical studies in nonhuman primates--have focused on blocking the 'classical' B7/CD28 and CD40/CD40L pathways, which are critical in primary T-cell activation.

Genetic and functional analyses of membrane cofactor protein (CD46) mutations in atypical hemolytic uremic syndrome.

Hemolytic uremic syndrome (HUS) is characterized by the triad of thrombocytopenia, microangiopathic hemolytic anemia, and acute renal failure. The non-Shiga toxin-associated HUS (atypical HUS [aHUS]) has been shown to be a disease of complement dysregulation. Mutations in the plasma complement regulators factor H and factor I and the widely expressed membrane cofactor protein (MCP; CD46) have been described recently.

Parvovirus B19-induced anemia in renal transplantation: a role for rHuEPO in resistance to classical treatment.

Human parvovirus B19 (PVB 19) is responsible for pure red cell aplasia in immunocompromised patients, and particularly solid organ recipients. Intravenous immunoglobulins (IVIG) have been shown to be efficient to achieve the correction of anemia in association with the reduction of immunosuppression. We report a case of kidney transplant recipient with PVB 19-induced anemia that did not respond to recombinant human erythropoietin (rHuEPO) and to a first course of IVIG.

A novel biological assay to detect the active form of TGF-beta in urine to monitor renal allograft rejection.

Background: Transforming growth factor-beta (TGF-beta) plays an important role in renal fibrosis. Measurement of the concentration of the active form of TGF-beta particularly in urine may help our understanding of the mechanism of chronic allograft nephropathy and could be used as a diagnostic tool. However, TGF-beta release and activation are complex and, consequently, there is currently no accurate way to measure TGF-beta activity.

Immunological strategies targeting B cells in organ grafting.

After delayed-type hypersensitivity and T cell cytotoxicity, the production of alloantibodies is the third effector mechanism contributing to graft injury. Histological characterization of antibody-mediated rejection and the detection of donor-reactive antibodies have highlighted the role of humoral immunity in acute and chronic rejection. A potential way of achieving central B cell tolerance is to induce complete chimerism with a myeloablative regimen and bone marrow transplant.

Recovery from pure red cell aplasia caused by anti-erythropoietin antibodies after kidney transplantation.

The use of recombinant human erythropoietin (rHuEPO) is a major advance in the treatment of patients with anemia caused by chronic renal failure (CRF). The development of antierythropoietin (anti-EPO) antibodies following treatment with rHuEPO has been observed in an increasing number of patients. This causes pure red cell aplasia (PRCA) and requires the definitive withdrawal of rHuEPO.