AKI leads to tubular injury and interstitial inflammation that must be controlled to avoid the development of fibrosis. We hypothesized that microRNAs are involved in the regulation of the balance ...between lesion formation and adaptive repair. We found that, under proinflammatory conditions, microRNA-146a (miR-146a) is transcriptionally upregulated by ligands of IL-1 receptor/Toll-like receptor family members via the activation of NF-κB in cultured renal proximal tubular cells. In vivo, more severe renal ischemia-reperfusion injury (IRI) associated with increased expression of miR-146a in both allografts and urine of human kidney transplant recipients, and unilateral IRI in mice induced miR-146a expression in injured kidneys. After unilateral IRI, miR-146a
mice exhibited more extensive tubular injury, inflammatory infiltrates, and fibrosis than wild-type mice. In vitro, overexpression or downregulation of miR-146a diminished or enhanced, respectively, IL-1 receptor-associated kinase 1 expression and induced similar effects on C-X-C motif ligand 8 (CXCL8)/CXCL1 expression by injured tubular cells. Moreover, inhibition of CXCL8/CXCL1 signaling prevented the development of inflammation and fibrosis after IRI in miR-146a
mice. In conclusion, these results indicate that miR-146a is a key mediator of the renal tubular response to IRI that limits the consequences of inflammation, a key process in the development of AKI and CKD.
Nonalcoholic fatty liver disease (NAFLD) is a spectrum of diseases including steatosis, nonalcoholic steatohepatitis (NASH), cirrhosis, and end-stage liver failure. Hepatic iron accumulation has been ...linked to hepatic fibrosis severity in NASH and NAFLD. Iron overload induced by parenteral (IV) iron therapy is a potential clinical problem in dialysis patients. We analyzed the hypothetical triggering and aggravating role of iron on NAFLD in patients on dialysis.
Liver iron concentration (LIC) and hepatic proton density fat fraction (PDFF) were analyzed prospectively in 68 dialysis patients by magnetic resonance imaging (MRI). Follow up of LIC and PDFF was performed in 17 dialysis patients during iron therapy.
PDFF differed significantly among dialysis patients classified according to LIC: patients with moderate or severe iron overload had increased fat fraction (PDFF: 7.9% (0.5–14.8%)) when compared to those with normal LIC (PDFF: 5% (0.27–11%)) or mild iron overload (PDFF: 5% (0.30–11.6%); P = 0.0049). PDFF correlated with LIC, and ferritin and body mass index. In seven patients monitored during IV iron therapy, LIC and PDFF increased concomitantly (PDFF: initial 2.5%, final 8%, P = 0.0156; LIC: initial 20 μmol/g, final 160 μmol/g: P = 0.0156), whereas in ten patients with iron overload, PDFF decreased after IV iron withdrawal or major dose reduction (initial: 8%, final: 4%; P = 0.0098) in parallel with LIC (initial: 195 μmol/g, final: 45 μmol/g; P = 0.002).
Liver iron load influences hepatic fat fraction in dialysis patients. Iron overload induced by iron therapy may aggravate or trigger NAFLD in dialysis patients.
80100088.
Iron overload, diagnosed by means of magnetic resonance imaging (MRI), is an increasingly recognized disorder in hemodialysis patients. Specific MRI protocols have been shown to provide a reliable ...estimation of tissue iron content in non-renal patient populations but have not been validated in dialysis patients. Such validation studies require liver biopsy for histological comparison, but this invasive and risky procedure raises ethical concerns, especially regarding frail patients with end-stage renal disease.
We compared in a pilot study Scheuer’s histological classification and Deugnier and Turlin’s histological classification of iron overload (Perls staining) with signal-intensity-ratio MRI values obtained with the Rennes University algorithm in 11 hemodialysis patients in whom liver biopsy was formally indicated for their medical follow-up.
For Scheuer’s histological classification, the Wilcoxon non-parametric matched-pairs test showed no significant difference in the ranking of iron overload by the two methods eg histology and MRI (sum of ranks = 1.5; p = 1). The MRI and Scheuer’s histological classifications were tightly correlated (rho = 0.866, p = 0.0035, Spearman’s coefficient), as were the absolute liver iron concentrations (LIC) at MRI (rho = 0.860, p = 0.0013, Spearman’s coefficient). The absolute liver iron concentrations at MRI were also highly correlated with Deugnier and Turlin’s histological scoring (rho = 0.841, p = 0.0033, Spearman’s coefficient).
This pilot study shows that liver iron determination based on signal-intensity-ratio MRI (Rennes University algorithm) very accurately identifies iron load in hemodialysis patients, by comparison with liver histology.
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. After the second kidney transplantation, only 2 cases showed recurrence of skin KS, one with previous complete remission of KS and one with partial remission. The mean delay between stability or complete remission of KS and retransplantation was 2.0 and 7.3 years in patients with and without relapse, respectively. Both recurrent cases showed complete KS remission after tapering immunosuppression therapy and/or switching a calcineurin inhibitor to a mammalian target of rapamycin inhibitor. We compared these 8 cases to 24 controls who had undergone 2 kidney transplantations but did not have KS, matching on sex, age and phototype. Cases and controls did not differ in graft function or survival. A second kidney transplantation may be possible after pt‐KS and has acceptable risk, especially after a long complete remission of pt‐KS.
Abstract
Background. Patients on kidney replacement therapy comprise a vulnerable population and may be at increased risk of death from coronavirus disease 2019 (COVID-19). Currently, only limited ...data are available on outcomes in this patient population.
Methods. We set up the ERACODA (European Renal Association COVID-19 Database) database, which is specifically designed to prospectively collect detailed data on kidney transplant and dialysis patients with COVID-19. For this analysis, patients were included who presented between 1 February and 1 May 2020 and had complete information available on the primary outcome parameter, 28-day mortality.
Results. Of the 1073 patients enrolled, 305 (28%) were kidney transplant and 768 (72%) dialysis patients with a mean age of 60 ± 13 and 67 ± 14 years, respectively. The 28-day probability of death was 21.3% 95% confidence interval (95% CI) 14.3–30.2% in kidney transplant and 25.0% (95% CI 20.2–30.0%) in dialysis patients. Mortality was primarily associated with advanced age in kidney transplant patients, and with age and frailty in dialysis patients. After adjusting for sex, age and frailty, in-hospital mortality did not significantly differ between transplant and dialysis patients hazard ratio (HR) 0.81, 95% CI 0.59–1.10, P = 0.18. In the subset of dialysis patients who were a candidate for transplantation (n = 148), 8 patients died within 28 days, as compared with 7 deaths in 23 patients who underwent a kidney transplantation <1 year before presentation (HR adjusted for sex, age and frailty 0.20, 95% CI 0.07–0.56, P < 0.01).
Conclusions. The 28-day case-fatality rate is high in patients on kidney replacement therapy with COVID-19 and is primarily driven by the risk factors age and frailty. Furthermore, in the first year after kidney transplantation, patients may be at increased risk of COVID-19-related mortality as compared with dialysis patients on the waiting list for transplantation. This information is important in guiding clinical decision-making, and for informing the public and healthcare authorities on the COVID-19-related mortality risk in kidney transplant and dialysis patients.
Acute clinical antibody-mediated rejection is currently defined by (1), an acute renal failure occurring during the first months following transplantation, (2), at least a microcirculation ...inflammation (glomerulitis and peritubular capillaritis) on kidney biopsy and (3), the presence in peripheral blood of donor specific antibodies, mostly anti-human leukocyte antigen (HLA) antibodies. The prognosis of this rejection is scored using the severity of vascular lesions and the positivity of C4d on peritubular capillaries. Recently, a subclinical variety of antibody-mediated rejection was recognized as an entity because, as the clinical rejection, it leads to chronic antibody-mediated rejection, currently the most frequent cause of graft loss. The description of these various aspects of antibody-mediated rejection allowed a better understanding of its pathophyiology that may lead in a near future to a more specific treatment.
Almost all haemodialysis patients are treated with parenteral iron to compensate for blood loss and to allow the full therapeutic effect of erythropoiesis-stimulating agents. Iron overload is an ...increasingly recognised clinical situation diagnosed by quantitative magnetic resonance imaging (MRI). MRI methods have not been fully validated in dialysis patients. We compared Deugnier's and Turlin's histological scoring of iron overload and Scheuer's classification (with Perls' stain) with three quantitative MRI methods for measuring liver iron concentration (LIC)-signal intensity ratio (SIR), R2* relaxometry, and R2* multi-peak spectral modelling (Iterative Decomposition of water and fat with Echo Asymmetry and Least-squares estimation (IDEAL-IQ
)) relaxometry-in 16 haemodialysis patients in whom a liver biopsy was formally indicated for medical follow-up. LIC MRI with these three different methods was highly correlated with Deugnier's and Turlin's histological scoring (SIR:
= 0.8329,
= 0.0002; R2* relaxometry:
= -0.9099,
< 0.0001; R2* relaxometry (IDEAL-IQ
):
= -0.872,
= 0.0018). Scheuer's classification was also significantly correlated with these three MRI techniques. The positive likelihood ratio for the diagnosis of abnormal LIC by Deugnier's histological scoring was > 62 for the three MRI methods. This study supports the accuracy of quantitative MRI methods for the non-invasive diagnosis and follow-up of iron overload in haemodialysis patients.
Background: Nonalcoholic fatty liver disease (NAFLD) is a spectrum of diseases including steatosis, nonalcoholic steatohepatitis (NASH), cirrhosis, and end-stage liver failure. Hepatic iron ...accumulation has been linked to hepatic fibrosis severity in NASH and NAFLD. Iron overload induced by parenteral (IV) iron therapy is a potential clinical problem in dialysis patients. We analyzed the hypothetical triggering and aggravating role of iron on NAFLD in patients on dialysis. Methods: Liver iron concentration (LIC) and hepatic proton density fat fraction (PDFF) were analyzed prospectively in 68 dialysis patients by magnetic resonance imaging (MRI). Follow up of LIC and PDFF was performed in 17 dialysis patients during iron therapy. Findings: PDFF differed significantly among dialysis patients classified according to LIC: patients with moderate or severe iron overload had increased fat fraction (PDFF: 7.9% (0.5–14.8%)) when compared to those with normal LIC (PDFF: 5% (0.27–11%)) or mild iron overload (PDFF: 5% (0.30–11.6%); P = 0.0049). PDFF correlated with LIC, and ferritin and body mass index. In seven patients monitored during IV iron therapy, LIC and PDFF increased concomitantly (PDFF: initial 2.5%, final 8%, P = 0.0156; LIC: initial 20 μmol/g, final 160 μmol/g: P = 0.0156), whereas in ten patients with iron overload, PDFF decreased after IV iron withdrawal or major dose reduction (initial: 8%, final: 4%; P = 0.0098) in parallel with LIC (initial: 195 μmol/g, final: 45 μmol/g; P = 0.002). Interpretation: Liver iron load influences hepatic fat fraction in dialysis patients. Iron overload induced by iron therapy may aggravate or trigger NAFLD in dialysis patients. Trial registration number (ISRCTN): 80100088. Keywords: Dialysis, Iron overload, MRI, Liver iron concentration (LIC), Liver proton density fat fraction (liver-PDFF), NAFLD
Aspects actuels des rejets aigus humoraux Legendre, Christophe; Loupy, Alexandre; Rabant, Marion ...
Néphrologie & thérapeutique,
November 2014, Letnik:
10, Številka:
6
Journal Article
Recenzirano
Le rejet aigu humoral clinique est défini par (1) une insuffisance rénale aiguë survenant dans les premiers mois de la transplantation, (2) sur le plan histologique, au minimum un aspect ...d’inflammation de la microcirculation rénale (glomérulite et capillarite péritubulaire) et (3) la présence dans le sang périphérique d’anticorps dirigés contre le donneur, le plus souvent anti-human leukocyte antigen (HLA). La sévérité du rejet aigu clinique est appréciée grâce à l’évaluation des lésions vasculaires et de la positivité du C4d sur les capillaires péritubulaires. On sait désormais qu’il existe un rejet aigu humoral infraclinique qui, comme la forme clinique, fait le lit du rejet chronique humoral qui est, à l’heure actuelle, probablement la principale cause de perte tardive des greffons. Le démembrement de ces différentes formes de rejet a permis de mieux comprendre leur physiopathologie et d’envisager, dans un futur proche, un traitement plus adapté.
Acute clinical antibody-mediated rejection is currently defined by (1), an acute renal failure occurring during the first months following transplantation, (2), at least a microcirculation inflammation (glomerulitis and peritubular capillaritis) on kidney biopsy and (3), the presence in peripheral blood of donor specific antibodies, mostly anti-human leukocyte antigen (HLA) antibodies. The prognosis of this rejection is scored using the severity of vascular lesions and the positivity of C4d on peritubular capillaries. Recently, a subclinical variety of antibody-mediated rejection was recognized as an entity because, as the clinical rejection, it leads to chronic antibody-mediated rejection, currently the most frequent cause of graft loss. The description of these various aspects of antibody-mediated rejection allowed a better understanding of its pathophyiology that may lead in a near future to a more specific treatment.
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