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1.
J Clin Med ; 9(3)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143501

RESUMO

In patients presenting with anti-glomerular basement membrane (GBM) disease with advanced isolated kidney involvement, the benefit of intensive therapy remains controversial due to adverse events, particularly infection. We aim to describe the burden of severe infections (SI) (requiring hospitalization or intravenous antibiotics) and identify predictive factors of SI in a large cohort of patients with anti-GBM disease. Among the 201 patients (median [IQR] age, 53 [30-71] years) included, 74 had pulmonary involvement and 127 isolated glomerulonephritis. A total of 161 SI occurred in 116 patients during the first year after diagnosis. These infections occurred during the early stage of care (median [IQR] time, 13 [8-19] days after diagnosis) with mainly pulmonary (45%), catheter-associated bacteremia (22%) and urinary tract (21%) infections. In multivariable analysis, positive ANCA (HR [95\% CI] 1.62 [1.07--2.44]; p = 0.02) and age at diagnosis (HR [95% CI] 1.10 [1.00-1.21]; p = 0.047) remained independently associated with SI. Age-adjusted severe infection during the first three months was associated with an increased three-year mortality rate (HR [95% CI] 3.13 [1.24-7.88]; p = 0.01). Thus, SI is a common early complication in anti-GBM disease, particularly in the elderly and those with positive anti-neutrophil cytoplasmic antibodies (ANCA). No significant association was observed between immunosuppressive strategy and occurrence of SI.

2.
Am J Transplant ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32167213

RESUMO

Acute tubular necrosis (ATN), a frequent histopathological feature in the early post-renal transplant biopsy, affects long-term graft function. Appropriate markers to identify patients at risk of no or incomplete recovery after delayed graft function are lacking. In this study, we first included 41 renal transplant patients whose biopsy for cause during the first month after transplantation showed ATN lesions. Using partial microvasculature endothelial (fascin, vimentin) and tubular epithelial (vimentin) to mesenchymal transition markers, detected by immunohistochemistry, we found a significant association between partial endothelial to mesenchymal transition (pEndMT) and poor graft function recovery (Spearman's rho= -0.55, P=0.0005). Transforming growth factor-beta1 was strongly expressed in these phenotypic changed endothelial cells. Extent of ATN was also correlated with short- and long-term graft dysfunction. However, the association of extensive ATN with long-term graft dysfunction (24 months posttransplant) was observed only in patients with pEndMT marker expression in their grafts (Spearman's rho= -0.64, P=0.003), but not in those without. The association of pEndMT with worse renal graft outcome was confirmed on 34 other early biopsies with ATN from a second transplant center. Our results suggest endothelial cell activation at the early phase of renal transplantation plays a detrimental role.

3.
Toxins (Basel) ; 12(2)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31973203

RESUMO

The severity of human infection by one of the many Shiga toxin-producing Escherichia coli (STEC) is determined by a number of factors: the bacterial genome, the capacity of human societies to prevent foodborne epidemics, the medical condition of infected patients (in particular their hydration status, often compromised by severe diarrhea), and by our capacity to devise new therapeutic approaches, most specifically to combat the bacterial virulence factors, as opposed to our current strategies that essentially aim to palliate organ deficiencies. The last major outbreak in 2011 in Germany, which killed more than 50 people in Europe, was evidence that an effective treatment was still lacking. Herein, we review the current knowledge of STEC virulence, how societies organize the prevention of human disease, and how physicians treat (and, hopefully, will treat) its potentially fatal complications. In particular, we focus on STEC-induced hemolytic and uremic syndrome (HUS), where the intrusion of toxins inside endothelial cells results in massive cell death, activation of the coagulation within capillaries, and eventually organ failure.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31778191

RESUMO

BACKGROUND: Long-term studies have demonstrated a slight increased risk for end-stage renal disease (ESRD) for living kidney donors (LKD). In France, living kidney donation doubled within the past 10 years. We investigated the change in characteristics of LKD between 2007 and 2017 and the adequacy of follow-up. METHODS: Data were obtained from the national registry for LKD. We compared characteristics of LKD between two study periods: 2007-11 and 2012-17, and stratified donors by age and relation to recipient. We aggregated four characteristics associated with higher ESRD risk [young age, first-degree relation to recipient, obesity, low glomerular filtration rate (GFR) for age] in a single risk indicator ranging from 0 to 4. RESULTS: We included 3483 donors. The proportion of unrelated donors >56 years of age increased significantly. The proportion of related donors <56 years of age decreased significantly. The body mass index and proportion of obese donors did not change significantly. The proportion of donors with low estimated GFR for age decreased significantly from 5% to 2.2% (P < 0.001). The proportion of donors with adequate follow-up after donation increased from 19.6% to 42.5% (P < 0.001). No donor had a risk indicator equal to 4, and the proportion of donors with a risk indicator equal to 0 increased significantly from 19.2% to 24.9% (P < 0.001). CONCLUSIONS: An increase in living kidney donation in France does not seem to be associated with the selection of donors at higher risk of ESRD and the proportion of donors with adequate annual follow-up significantly increased.

7.
BMJ ; 366: l4923, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530561

RESUMO

OBJECTIVE: To develop and validate an integrative system to predict long term kidney allograft failure. DESIGN: International cohort study. SETTING: Three cohorts including kidney transplant recipients from 10 academic medical centres from Europe and the United States. PARTICIPANTS: Derivation cohort: 4000 consecutive kidney recipients prospectively recruited in four French centres between 2005 and 2014. Validation cohorts: 2129 kidney recipients from three centres in Europe and 1428 from three centres in North America, recruited between 2002 and 2014. Additional validation in three randomised controlled trials (NCT01079143, EudraCT 2007-003213-13, and NCT01873157). MAIN OUTCOME MEASURE: Allograft failure (return to dialysis or pre-emptive retransplantation). 32 candidate prognostic factors for kidney allograft survival were assessed. RESULTS: Among the 7557 kidney transplant recipients included, 1067 (14.1%) allografts failed after a median post-transplant follow-up time of 7.12 (interquartile range 3.51-8.77) years. In the derivation cohort, eight functional, histological, and immunological prognostic factors were independently associated with allograft failure and were then combined into a risk prediction score (iBox). This score showed accurate calibration and discrimination (C index 0.81, 95% confidence interval 0.79 to 0.83). The performance of the iBox was also confirmed in the validation cohorts from Europe (C index 0.81, 0.78 to 0.84) and the US (0.80, 0.76 to 0.84). The iBox system showed accuracy when assessed at different times of evaluation post-transplant, was validated in different clinical scenarios including type of immunosuppressive regimen used and response to rejection therapy, and outperformed previous risk prediction scores as well as a risk score based solely on functional parameters including estimated glomerular filtration rate and proteinuria. Finally, the accuracy of the iBox risk score in predicting long term allograft loss was confirmed in the three randomised controlled trials. CONCLUSION: An integrative, accurate, and readily implementable risk prediction score for kidney allograft failure has been developed, which shows generalisability across centres worldwide and common clinical scenarios. The iBox risk prediction score may help to guide monitoring of patients and further improve the design and development of a valid and early surrogate endpoint for clinical trials. TRIAL REGISTRATION: Clinicaltrials.gov NCT03474003.


Assuntos
Rejeição de Enxerto/etiologia , Transplante de Rim , Adulto , Idoso , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco/métodos , Estados Unidos/epidemiologia
8.
Front Immunol ; 10: 1665, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396214

RESUMO

We report the overall and renal outcome in a French nationwide multicenter cohort of 119 patients with anti-glomerular basement membrane (anti-GBM) disease. Sixty-four patients (54%) had an exclusive renal involvement, 7 (6%) an isolated alveolar hemorrhage and 48 (40%) a combined renal and pulmonary involvement. Initial renal replacement therapy (RRT) was required in 78% of patients; 82% received plasmapheresis, 82% cyclophosphamide, and 9% rituximab. ANCA positive (28%) patients were older (70 vs. 47 years, p < 0.0001), less frequently smokers (26 vs. 54%, p = 0.03), and had less pulmonary involvement than ANCA- patients. The 5 years overall survival was 92%. Risk factors of death (n = 11, 9.2%) were age at onset [HR 4.10 per decade (1.89-8.88) p = 0.003], hypertension [HR 19.9 (2.52-157 0.2) p = 0.005], dyslipidemia [HR 11.1 (2.72-45) p = 0.0008], and need for mechanical ventilation [HR 5.20 (1.02-26.4) p = 0.047]. The use of plasmapheresis was associated with better survival [HR 0.29 (0.08-0.98) p = 0.046]. At 3 months, 55 (46%) patients had end-stage renal disease (ESRD) vs. 37 (31%) ESRD-free and 27 (23%) unevaluable with follow-up < 3 months. ESRD patients were older, more frequently female and had a higher serum creatinine level at presentation than those without ESRD. ESRD-free survival was evaluated in patients alive without ESRD at 3 months (n = 37) using a landmark approach. In conclusion, this large French nationwide study identifies prognosis factors of renal and overall survival in anti-GBM patients.

11.
Kidney Int ; 95(6): 1471-1485, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30955869

RESUMO

Human leukocyte antigen (HLA) mismatching and minimization of immunosuppression are two major risk factors for the development of de novo donor-specific antibodies, which are associated with reduced kidney graft survival. Antibodies do not recognize whole HLA antigens but rather individual epitopes, which are short sequences of amino acids in accessible positions. However, compatibility is still assessed by the simple count of mismatched HLA antigens. We hypothesized that the number of mismatched epitopes, or ("epitope load") would identify patients at the highest risk of developing donor specific antibodies following minimization of immunosuppression. We determined epitope load in 89 clinical trial participants who converted from cyclosporine to everolimus 3 months after kidney transplantation. Twenty-nine participants (32.6%) developed de novo donor specific antibodies. Compared to the number of HLA mismatches, epitope load was more strongly associated with the development of donor specific antibodies. Participants with an epitope load greater than 27 had a 12-fold relative risk of developing donor-specific antibodies compared to those with an epitope load below that threshold. Using that threshold, epitope load would have missed only one participant who subsequently developed donor specific antibodies, compared to 8 missed cases based on a 6-antigen mismatch. DQ7 was the most frequent antigenic target of donor specific antibodies in our population, and some DQ7 epitopes appeared to be more frequently involved than others. Assessing epitope load before minimizing immunosuppression may be a more efficient tool to identify patients at the highest risk of allosensitization.

12.
Am J Transplant ; 19(9): 2434-2445, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30836425

RESUMO

Graft microvasculature is a major target of donor-specific antibodies (DSA) and endothelial damage is direct evidence of antibody-mediated rejection (ABMR). Using immunohistochemistry, we analyzed the expression of three microvascular endothelial activation markers (fascin, vimentin, and hsp47), suggestive of endothelial-to-mesenchymal transition (EndMT) in 351 graft biopsies from 248 kidney recipients, with concomitant screening of circulating antihuman leukocyte antigen (HLA) DSA at the time of the biopsy. The factors associated with EndMT marker expression were DSA and the presence of microvascular inflammation (MI). EndMT expressing grafts had significantly more allograft loss compared to EndMT negative grafts (P < .0001). The expression of EndMT markers positively correlated with anti-HLA DSA class II mean fluorescence intensity (MFI) levels and especially identified DQ and DR antibodies as being more closely associated with microvascular injury. Moreover, only DSA linked to positive EndMT score affected allograft survival, regardless of DSA MFI levels or presence of C4d deposition. Thus, EndMT markers could represent a clinically relevant tool for early identification of ongoing endothelial injury, harmful DSA, and patients at high risk for allograft failure.

13.
J Am Soc Nephrol ; 30(4): 692-709, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30850439

RESUMO

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). We developed a crossmatch assay to assess serum reactivity to human microvascular endothelial cells, and used a combination of transcriptomic and proteomic approaches to identify non-HLA Abs. RESULTS: We identified a highly selected cohort of 38 patients with early acute AMVR. Biopsy specimens revealed intense microvascular inflammation and the presence of vasculitis (in 60.5%), interstitial hemorrhages (31.6%), or thrombotic microangiopathy (15.8%). Serum samples collected at the time of transplant showed that previously proposed anti-endothelial cell Abs-angiotensin type 1 receptor (AT1R), endothelin-1 type A and natural polyreactive Abs-did not increase significantly among patients with AMVR compared with a control group of stable kidney transplant recipients. However, 26% of the tested AMVR samples were positive for AT1R Abs when a threshold of 10 IU/ml was used. The crossmatch assay identified a common IgG response that was specifically directed against constitutively expressed antigens of microvascular glomerular cells in patients with AMVR. Transcriptomic and proteomic analyses identified new targets of non-HLA Abs, with little redundancy among individuals. CONCLUSIONS: Our findings indicate that preformed IgG Abs targeting non-HLA antigens expressed on glomerular endothelial cells are associated with early AMVR, and that in vitro cell-based assays are needed to improve risk assessments before transplant.


Assuntos
Rejeição de Enxerto/imunologia , Hemorragia/imunologia , Imunoglobulina G/sangue , Receptor Tipo 1 de Angiotensina/imunologia , Microangiopatias Trombóticas/imunologia , Vasculite/imunologia , Doença Aguda , Adulto , Idoso , Células Endoteliais/imunologia , Endotelina-1/imunologia , Feminino , Rejeição de Enxerto/patologia , Rejeição de Enxerto/fisiopatologia , Hemorragia/patologia , Humanos , Glomérulos Renais/patologia , Transplante de Rim/efeitos adversos , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Microangiopatias Trombóticas/patologia , Fatores de Tempo , Vasculite/patologia
14.
Am J Respir Crit Care Med ; 199(9): 1066-1075, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30785784

RESUMO

Acute kidney injury (AKI) affects many ICU patients and is responsible for increased morbidity and mortality. Although lifesaving in many situations, renal replacement therapy (RRT) may be associated with complications, and the appropriate timing of its initiation is still the subject of intense debate. An early initiation strategy can prevent some metabolic complications, whereas a delayed one may allow for renal function recovery in some patients without need for this costly and potentially dangerous technique. For years, most of the knowledge on this issue stemmed from observational studies or small randomized controlled trials. Recent randomized controlled trials have indicated that a watchful waiting strategy (in the absence of life-threatening conditions such as severe hyperkalemia or pulmonary edema) during severe AKI allowed many patients to escape RRT and did not seem to adversely affect survival compared with a strategy of immediate RRT. In addition, data suggest that a delayed strategy may reduce the rate of complications (such as catheter infection) and favor renal function recovery. Ongoing studies will have to both confirm these conclusions and clarify to what extent the delay in initiating RRT can be prolonged. Pending those results, the bulk of evidence suggests that, in the absence of potential severe complications of AKI, delaying RRT is a valid and safe strategy that may also allow for considerable cost savings.


Assuntos
Lesão Renal Aguda/terapia , Terapia de Substituição Renal/métodos , Estado Terminal/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
15.
Artigo em Inglês | MEDLINE | ID: mdl-30805631

RESUMO

BACKGROUND: Among the severe complications of preeclampsia (PE), acute kidney injury (AKI) is problematic if features of thrombotic microangiopathy (TMA) are present. Although a haemolysis enzyme liver low-platelets syndrome is considerably more frequent, it is vital to rule out a flare of atypical haemolytic and uraemic syndrome (aHUS). Our objective was to improve differential diagnosis procedures in post-partum AKI. METHODS: A total of 105 cases of post-partum AKI, admitted to nine different regional French intensive care units from 2011 to 2015, were analysed. Analysis included initial and final diagnosis, renal features, haemostasis and TMA parameters, with particular focus on the dynamics of each component within the first days following delivery. A classification and regression tree (CART) was used to construct a diagnostic algorithm. RESULTS: AKI was attributed to severe PE (n = 40), post-partum haemorrhage (n = 33, including 13 renal cortical necrosis) and 'primary' TMA (n = 14, including 10 aHUS and 4 thrombotic thrombocytopenic purpura). Congruence between initial and final diagnosis was low (63%). The dynamics of haemoglobin, haptoglobin and liver enzymes were poorly discriminant. In contrast, the dynamic pattern of platelets was statistically different between primary TMA-related AKI and other groups. CART analysis independently highlighted the usefulness of platelet trajectory in the diagnostic algorithm. Limitations of this study include that only the most severe cases were included in this retrospective study, and the circumstantial complexity is high. CONCLUSION: Trajectory of platelet count between admission and Day 3 helps to guide therapeutic decisions in cases of TMA-associated post-partum AKI. Our study also strongly suggests that during the post-partum period, there may be a risk of transient, slowly recovering TMA in cases of severe endothelial injury in women without a genetic mutation known to induce aHUS.

17.
Nephrol Dial Transplant ; 34(11): 1819-1826, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30403811

RESUMO

Preeclampsia is a hypertensive disorder of pregnancy and the clinical manifestation of severe endothelial dysfunction associated with maternal and foetal morbidity and mortality. The primum movens of the disease is the defect of invasion of the uterine arteries by foetal syncytiotrophoblasts, which causes a maladaptive placental response to chronic hypoxia and the secretion of the soluble form of type 1 vascular growth endothelial factor receptor, also called soluble fms-like tyrosine kinase 1 (sFlt-1), the major player in the pathophysiology of the disease. Among its different effects, sFlt-1 induces abnormal sensitivity of the maternal vessels to the vasoconstrictor angiotensin II. This leads to the hypertensive phenotype, recently shown to be abrogated by the administration of sildenafil citrate, which can potentiate the vasodilatory mediator nitrite oxide. This review focuses on the mechanisms of maternal endothelial dysfunction in preeclampsia and discusses the therapeutic window of sildenafil use in the context of preeclampsia, based on the results from preclinical studies and clinical trials. Safety issues recently reported in neonates have considerably narrowed this window.

19.
Eur J Obstet Gynecol Reprod Biol ; 231: 70-74, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30326377

RESUMO

OBJECTIVE: Severe preeclampsia may require the delivery of the placenta to avoid life-threatening complications for the mother. Before 26 weeks of gestation, this often results in perinatal death. A decrease in soluble fms-like tyrosine kinase 1 (sFlt1), an anti-angiogenic factor central to the pathophysiology of the maternal syndrome, has been reported after LDL- apheresis. The present study tested whether LDL-apheresis could be used to allow women with early and severe preeclampsia to reach a gestational age where the baby had a viable chance of survival. STUDY DESIGN: A phase II prospective study. Adult women were included if they had very early (<26 weeks of gestation) preeclampsia without severe (<5th percentile) intra-uterine growth retardation. Treatment consisted of two weekly sessions (90 min each) of LDL-apheresis of whole blood. The primary endpoint was the status of the baby (dead or living) at 6 months post-delivery. Sample size and stopping rules were calculated assuming a desired success rate of at least 90%. RESULTS: The study was interrupted for safety reasons after the inclusion of two patients: both developed secondary uncontrolled hypertension and blurred vision during the first week of treatment. The first neonate, born at 25 + 3 weeks of gestation, died of sepsis at day 5; the second, born at 26 + 2 weeks of gestation, is still alive and well. In these two patients, the impact of apheresis sessions on sFlt1 concentrations was inconsistent. CONCLUSION: LDL-apheresis did not result in the prolongation of pregnancy in this phase II trial. Further studies will be needed to delineate the appropriate contours of this therapeutic strategy.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Pré-Eclâmpsia/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Remoção de Componentes Sanguíneos/efeitos adversos , Evolução Fatal , Feminino , Idade Gestacional , Humanos , Hipertensão/etiologia , Recém-Nascido , Lipoproteínas LDL , Gravidez , Resultado da Gravidez , Nascimento Prematuro/prevenção & controle , Estudos Prospectivos
20.
Placenta ; 69: 40-49, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30213483

RESUMO

INTRODUCTION: Estrogens and progesterone play critical roles in angiogenesis and vasodilation. Moreover, placental aromatase deficiency is detected in women with preeclampsia (PE) at delivery. We hypothesized that abnormal steroidogenesis occurs much earlier than typical PE diagnosis. Thus, we investigated whether the circulating steroid profile was already disturbed at 24-29 weeks of gestation in women with subsequent PE, and compared the profile with that of women with "placental" small gestational age (SGA) without PE. METHODS: We selected nulliparous women (n = 90) from the MOMA trial, including women with PE (n = 25), SGA (n = 25), and controls (NP; n = 40), for plasma steroid profiling by gas chromatography/mass spectrometry and to measure placental growth factor and soluble fms-like tyrosine kinase-1. Placental aromatase expression was evaluated in a new set of women. RESULTS: Compared with that of controls, the women with PE had a significantly lower estrone/androstenedione ratio, and exhibited a decreasing trend for estradiol and estrone levels. Lower estriol levels were observed in the SGA group compared to the NP group. Compared with that of controls, the women with PE and SGA had significantly higher levels of 20α-dihydroprogesterone (20α-DHP) and 20α-DHP/progesterone ratios. Pregnenolone sulfate levels were lower in the PE group than in the NP and SGA groups. Decreased expression of aromatase was observed in the PE group compared to the control group. DISCUSSION: Preeclampsia appears to be characterized by specific steroidogenesis dysregulation long before PE diagnosis, highlighting potential new biomarkers of PE.


Assuntos
Aromatase/metabolismo , Estrogênios/sangue , Fator de Crescimento Placentário/sangue , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Androstenodiona/sangue , Estradiol/sangue , Estriol/sangue , Estrona/sangue , Feminino , Humanos , Espectrometria de Massas , Gravidez , Pregnenolona/sangue , Adulto Jovem
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