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We analyzed retrospective data from toxicology studies involving administration of high doses of adeno-associated virus expressing different therapeutic transgenes to 21 cynomolgus and 15 rhesus macaques. We also conducted prospective studies to investigate acute toxicity following high-dose systemic administration of enhanced green fluorescent protein-expressing adeno-associated virus to 10 rhesus macaques. Toxicity was characterized by transaminitis, thrombocytopenia, and alternative complement pathway activation that peaked on post-administration day 3. Although most animals recovered, some developed ascites, generalized edema, hyperbilirubinemia, and/or coagulopathy that prompted unscheduled euthanasia. Study endpoint livers from animals that recovered and from unscheduled necropsies of those that succumbed to toxicity were analyzed via hypothesis-driven histopathology and unbiased single-nucleus RNA sequencing. All liver cell types expressed high transgene transcript levels at early unscheduled timepoints that subsequently decreased. Thrombocytopenia coincided with sinusoidal platelet microthrombi and sinusoidal endothelial injury identified via immunohistology and single-nucleus RNA sequencing. Acute toxicity, sinusoidal injury, and liver platelet sequestration were similarly observed with therapeutic transgenes and enhanced green fluorescent protein at doses ≥1 × 1014 GC/kg, suggesting it was the consequence of high-dose systemic adeno-associated virus administration, not green fluorescent protein toxicity. These findings highlight a potential toxic effect of high-dose intravenous adeno-associated virus on nonhuman primate liver microvasculature.
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Dependovirus , Trombocitopenia , Animais , Dependovirus/genética , Macaca mulatta/genética , Estudos Prospectivos , Estudos Retrospectivos , Fígado/metabolismo , Transgenes , Trombocitopenia/metabolismo , Células Endoteliais , Vetores Genéticos/genéticaRESUMO
Atypical hemolytic uremic syndrome is a complement-mediated thrombotic microangiopathy caused by uncontrolled activation of the alternative complement pathway in the setting of autoantibodies to or rare pathogenic genetic variants in complement proteins. Pregnancy may serve as a trigger and unmask atypical hemolytic uremic syndrome/complement-mediated thrombotic microangiopathy (aHUS/CM-TMA), which has severe, life-threatening consequences. It can be difficult to diagnose aHUS/CM-TMA in pregnancy due to overlapping clinical features with other thrombotic microangiopathy syndromes including hypertensive disorders of pregnancy. However, the distinction among thrombotic microangiopathy etiologies in pregnancy is important because each syndrome has specific disease management and treatment. In this narrative review, we discuss 2 cases to illustrate the diagnostic challenges and evolving approach in the management of pregnancy-associated aHUS/CM-TMA. The first case involves a 30-year-old woman presenting in the first trimester who was diagnosed with aHUS/CM-TMA and treated with eculizumab from 19 weeks' gestation. Genetic testing revealed a likely pathogenic variant in CFI. She successfully delivered a healthy infant at 30 weeks' gestation. In the second case, a 22-year-old woman developed severe postpartum HELLP syndrome, requiring hemodialysis. Her condition improved with supportive management, yet investigations assessing for aHUS/CM-TMA remained abnormal 6 months postpartum consistent with persistent complement activation but negative genetic testing. Through detailed case discussion describing tests assessing for placental health, fetal anatomy, complement activation, autoantibodies to complement regulatory proteins, and genetic testing for aHUS/CM-TMA, we describe how these results aided in the clinical diagnosis of pregnancy-associated aHUS/CM-TMA and assisted in guiding patient management, including the use of anticomplement therapy.
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Síndrome Hemolítico-Urêmica Atípica , Microangiopatias Trombóticas , Adulto , Feminino , Humanos , Gravidez , Adulto Jovem , Síndrome Hemolítico-Urêmica Atípica/diagnóstico , Síndrome Hemolítico-Urêmica Atípica/genética , Síndrome Hemolítico-Urêmica Atípica/terapia , Autoanticorpos , Proteínas do Sistema Complemento/genética , Placenta , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/terapiaRESUMO
De novo thrombotic microangiopathy (dnTMA), after renal transplantation may significantly alter graft outcomes. However, its pathogenesis and the role of complement alternative pathway dysregulation remain elusive. We studied all consecutive adult patients with a kidney allograft biopsy performed between January 2004 and March 2016 displaying dnTMA. Ninety-two patients were included. The median time of occurrence was 166 (IQR 25-811) days. The majority (82.6 %) had TMA localized only in the graft. Calcineurin inhibitor toxicity and antibody-mediated rejection (ABMR) were the 2 most frequent causes (54.3% and 37.0%, respectively). However, etiological factors were multiple in 37% patients. Interestingly, pathogenic variants in the genes of complement alternative pathway were significantly more frequent in the 42 tested patients than in healthy controls (16.7% vs 3.7% respectively, P < .008). The overall graft survival after biopsy was 66.0% at 5 years and 23.4% at 10 years, significantly worse than a matched cohort without TMA. Moreover, graft survival of patients with TMA and ABMR was worse than a matched cohort with ABMR without TMA. The 2 main prognostic factors were a positive C4d staining and a lower estimated glomerular filtration rate at diagnosis. DnTMA is a severe and multifactorial disease, induced by 1 or several endothelium-insulting conditions, mostly calcineurin inhibitor toxicity and ABMR.
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Taxa de Filtração Glomerular , Rejeição de Enxerto , Sobrevivência de Enxerto , Transplante de Rim , Microangiopatias Trombóticas , Humanos , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/genética , Transplante de Rim/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Prognóstico , Seguimentos , Adulto , Fatores de Risco , Complicações Pós-Operatórias , Testes de Função Renal , Falência Renal Crônica/cirurgia , Estudos Retrospectivos , Proteínas do Sistema Complemento/genética , Estudos de Casos e ControlesRESUMO
To clarify the role of the C5a/C5aR (C5a receptor) and C5b-9 pathways in macrovascular thrombosis (MAT) and renal microthrombosis (MIT), 73 renal biopsy-proven complement-mediated thrombotic microangiopathy (C-TMA) patients were enrolled; 9 patients with pure MAT and 13 patients with pure MIT were selected for further study. Twenty-five external C-TMA patients were selected as the validation cohort. Plasma C5a and sC5b-9 (soluble C5b-9) levels were significantly higher in patients with MAT than in those with MIT (P = 0.008, P = 0.041, respectively). The mean optical density of C5aR1 in the kidney was significantly higher in MAT patients than in those with MIT (P < 0.001). Both urinary sC5b-9 levels (MIT: P < 0.001, MAT: P = 0.004) and renal deposition of C5b-9 (MIT: P < 0.001, MAT: P = 0.001) were significantly higher in C-TMA patients compared to normal control, but were similar between MAT and MIT groups. In the correlation analysis within 22C-TMA patients, urinary sC5b-9 levels and renal deposition of C5b-9 were positively correlated to renal MIT formation (P = 0.009 and P = 0.031, respectively). Furthermore, the renal citrullinated histone H3 (CitH3)- and neutrophil elastase (NE)-positive area ratios were both significantly higher in the MAT group than in the MIT group (P = 0.006 and P = 0.020, respectively). Therefore, the local C5b-9 and C5a/C5aR1 pathways might have differential contributions to MIT and MAT formation in the disease.
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Trombose , Microangiopatias Trombóticas , Humanos , Ativação do Complemento , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Proteínas do Sistema Complemento , Receptor da Anafilatoxina C5a , Complemento C5bRESUMO
Most reports of risk factors (RF) for developing transplant-associated thrombotic microangiopathy (TA-TMA) and death are derived from paediatric and young adult cohorts, with minimal data on differences in RF and outcomes by age. In this secondary CIBMTR analysis, we used a previously prepared dataset that included all first allogenic haematopoietic cell transplantation (HCT) recipients with malignant or non-malignant diseases between 2008 and 2016. The incidence of TA-TMA 6 months post HCT was similar in children and adults 2.1% and 2.0% respectively. Grade 2-4 acute graft-versus-host disease (aGVHD) was a significant adjusted RF for developing TA-TMA in both children and adults. In adults, additional adjusted RFs for TA-TMA included female sex and black race, and in children an unrelated donor. Compared to a calcineurin inhibitor and sirolimus, other forms of GVHD prophylaxis had an adjusted decreased risk of developing TA-TMA in adults. Adjusted RF for death in those with TA-TMA (n = 652) included age ≥18 years old, early onset of TA-TMA diagnosis (<100 days post HCT), grade 3-4 aGVHD and a performance score of <90 prior to HCT. In this cohort, the incidence of TA-TMA was similar in children and adults, and TA-TMA timing was a newly identified RF for death.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Microangiopatias Trombóticas , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/etiologia , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/epidemiologia , Microangiopatias Trombóticas/prevenção & controle , Feminino , Masculino , Criança , Adolescente , Adulto , Pré-Escolar , Pessoa de Meia-Idade , Fatores Etários , Adulto Jovem , Fatores de Risco , Fatores de Tempo , Lactente , IncidênciaRESUMO
A young adult African American female presented with normocytic microangiopathic haemolytic anaemia, elevated lactate dehydrogenase and thrombocytopenia. The patient responded to therapeutic plasma exchanges (TPE) for presumed thrombotic microangiopathy caused by thrombotic thrombocytopenic purpura (TTP). After relapsing, the patient was found to have pancytopenia, megaloblastic bone marrow and low vitamin B12 consistent with pernicious anaemia, which improved with intramuscular B12 and discontinuation of TPE. B12-deficient macrocytosis was not seen at presentation due to concomitant alpha-thalassaemia. Initial clinical/laboratory improvement is attributed to B12 present in TPE plasma. B12 deficiency can mimic TTP. Vigilance is needed regarding atypical presentations of pernicious anaemia.
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BACKGROUND: Hemolysis is a cardinal feature of hemolytic uremic syndrome (HUS) and during hemolysis excess arginase 1 is released from red blood cells. Increased arginase activity leads to reduced L-arginine, as it is converted to urea and L-ornithine, and thereby reduced nitric oxide bioavailability, with secondary vascular injury. The objective of this study was to investigate arginase release in HUS patients and laboratory models and correlate arginase levels to hemolysis and kidney injury. METHODS: Two separate cohorts of patients (n = 47 in total) with HUS associated with Shiga toxin-producing enterohemorrhagic E. coli (EHEC) and pediatric controls (n = 35) were investigated. Two mouse models were used, in which mice were either challenged intragastrically with E. coli O157:H7 or injected intraperitoneally with Shiga toxin 2. An in vitro model of thrombotic microangiopathy was developed in which Shiga toxin 2- and E. coli O157 lipopolysaccharide-stimulated human blood cells combined with ADAMTS13-deficient plasma were perfused over glomerular endothelial cells. Two group statistical comparisons were performed using the Mann-Whitney test, multiple groups were compared using the Kruskal-Wallis test followed by Dunn's procedure, the Wilcoxon signed rank test was used for paired data, or linear regression for continuous variables. RESULTS: HUS patients had excessively high plasma arginase 1 levels and activity (conversion of L-arginine to urea and L-ornithine) during the acute phase, compared to remission and controls. Arginase 1 levels correlated with lactate dehydrogenase activity, indicating hemolysis, as well as the need for dialysis treatment. Patients also exhibited high levels of plasma alpha-1-microglobulin, a heme scavenger. Both mouse models exhibited significantly elevated plasma arginase 1 levels and activity. Plasma arginase 1 levels correlated with lactate dehydrogenase activity, alpha-1-microglobulin and urea levels, the latter indicative of kidney dysfunction. In the in vitro model of thrombotic microangiopathy, bioactive arginase 1 was released and levels correlated to the degree of hemolysis. CONCLUSIONS: Elevated red blood cell-derived arginase was demonstrated in HUS patients and in relevant in vivo and in vitro models. The excessively high arginase levels correlated to the degree of hemolysis and kidney dysfunction. Thus, arginase inhibition should be investigated in HUS.
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Infecções por Escherichia coli , Escherichia coli O157 , Síndrome Hemolítico-Urêmica , Insuficiência Renal , Microangiopatias Trombóticas , Humanos , Criança , Animais , Camundongos , Toxina Shiga II , Células Endoteliais , Hemólise , Arginase , Síndrome Hemolítico-Urêmica/complicações , Síndrome Hemolítico-Urêmica/terapia , Eritrócitos , Microangiopatias Trombóticas/complicações , Ureia , Arginina , Ornitina , Lactato Desidrogenases , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/terapiaRESUMO
Catastrophic antiphospholipid syndrome (CAPS) is a severe condition with high mortality. Since its description in 1992, an important effort has been made to improve and disseminate knowledge on CAPS. Most of our current knowledge comes from the studies performed using the CAPS Registry, a database created in 2000 to gather as many cases as possible in order to better define this disease. It has demonstrated that this condition has multiple faces and is often triggered by a precipitating factor that leads to a thrombotic microangiopathy and cytokine storm involving almost any organ of the body. Analysis of the CAPS Registry has also shown that patients receiving anticoagulation, glucocorticoids and plasma exchange and/or IVIG have a better prognosis. However, there are still many unresolved questions. In this review we summarize what is known and what is still a matter of research in this condition.
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Síndrome Antifosfolipídica , Humanos , Imunoglobulinas Intravenosas , Troca Plasmática , Plasmaferese , Prognóstico , Doença Catastrófica/terapiaRESUMO
Transplantation-associated thrombotic microangiopathy (TA-TMA) is a well-recognized serious complication of hematopoietic stem cell transplantation (HSCT). The understanding of TA-TMA pathophysiology has expanded in recent years. Dysregulation of the complement system is thought to cause endothelial injury and, consequently, microvascular thrombosis and tissue damage. TA-TMA can affect multiple organs, and each organ exhibits specific features of injury. Central nervous system (CNS) manifestations of TA-TMA include posterior reversible encephalopathy syndrome, seizures, and encephalopathy. The development of neurological dysfunction is associated with a significantly lower overall survival in patients with TA-TMA. However, there are currently no established histopathological or radiological criteria for the diagnosis of CNS TMA. Patients who receive total body irradiation (TBI), calcineurin inhibitors (CNI), and severe acute and chronic graft-versus-host disease (GVHD) are at a high risk of experiencing neurological complications related to TA-TMA and should be considered for directed TA-TMA therapy. However, the incidence and clinical manifestations of TA-TMA neurotoxicity remain unclear. Studies specifically examining the involvement of CNS in TMA syndromes are limited. In this review, we discuss clinical manifestations and imaging abnormalities in patients with nervous system involvement in TA-TMA. We summarize the mechanisms underlying TA-TMA and its neurological complications, including endothelial injury, evidence of complement activation, and treatment options for TA-TMA.
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BACKGROUND AND HYPOTHESIS: Carfilzomib, a new proteasome inhibitor indicated for patients with relapsed/refractory myeloma, has been associated with cases of thrombotic microangiopathy (CFZ-TMA). The role of variants in the complement alternative pathway and therapeutic potential of complement blockade with eculizumab remain to be determined. METHODS: We report 37 cases of CFZ-TMA recorded in the French reference center for TMA with their clinical characteristics, genetic analysis and outcome according to treatments. RESULTS: A trigger was identified in more than half of cases, including 8 influenza and 5 SARS-CoV-2 cases. All patients presented with acute kidney injury (AKI) (KDIGO stage 3 in 31 (84%) patients) while neurological (n=13, 36%) and cardiac damage (n=7, 19%) were less frequent. ADAMTS13 and complement activity were normal (n= 28 and 18 patients tested) and no pathogenic variant in the alternative complement pathway was found in 7 patients tested.TMA resolved in most (n=34, 94%) patients but 12 (44%) still displayed stage 3 AKI at discharge. Nineteen (51%) patients were treated with therapeutic plasma exchange, 14 (38%) patients received corticosteroids and 18 (50%) were treated with eculizumab. However none of these treatments demonstrated a significant impact on outcomes. CONCLUSION: This study is the largest case series of CFZ-TMA since its approval in 2012. Patients present with severe AKI and experience frequent sequelae. Complement variants and blockade therapy do not seem to play a role in the pathophysiology and prognosis of the disease.
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BACKGROUND: While the prevalence of antiphospholipid antibodies (aPL) in venous and arterial thrombotic events had already been estimated by previous studies, the prevalence of aPL in subjects with Thrombotic Microangiopathy (TMA) is still not fully elucidated. Thus, we conducted a systematic review to estimate the frequency of aPL in subjects with biopsy-proven renal TMA. METHODS: We conducted in the PubMed database a search for English-language studies investigating the presence of aPL in subjects with biopsy-proven renal TMA from January 1985 to December 2022. Keywords used in the search included: 'antiphospholipid syndrome', 'antiphospholipid antibodies' and 'thrombotic microangiopathy'. Cohorts of HUS patients were excluded due to the risk of over-estimating the prevalence of aPL in these populations. The median frequency for positive aPL including anticardiolipin antibodies (aCL), antibodies against ß2-glycoprotein-I (anti-ß2GPI) and lupus anticoagulant (LA) was then calculated. RESULTS: 522 articles were identified through the literature search. Six studies, assessing the prevalence of aPL in 211 subjects with renal TMA, were retrieved. The overall aPL prevalence was estimated as 24.4% (range 22-56). The estimated prevalence of aCL (IgG/IgM), anti-ß2GPI, (IgG/IgM) and LA was 4.0% (range 3-27), 4.0% (range 3-16) and 18.9% (range 13-25), respectively. APS was diagnosed in 16.3% (range 11-29) of the patients. Of note, a high level of heterogeneity was observed when comparing the reported aPL profiles for each study. CONCLUSIONS: This comprehensive systematic analysis of studies investigating the prevalence of aPL in renal TMA showed that, despite the high heterogeneity of the included studies, aPL are present in about one case out of four renal-TMA cases.
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Síndrome Antifosfolipídica , Lúpus Eritematoso Sistêmico , Microangiopatias Trombóticas , Humanos , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/epidemiologia , Síndrome Antifosfolipídica/diagnóstico , Anticorpos Antifosfolipídeos , Prevalência , Inibidor de Coagulação do Lúpus , Anticorpos Anticardiolipina , Microangiopatias Trombóticas/epidemiologia , Imunoglobulina G , Imunoglobulina MRESUMO
BACKGROUND: Complement-mediated thrombotic microangiopathy (CM-TMA), also called atypical hemolytic uremic syndrome (aHUS), is a difficult-to-diagnose rare disease that carries severe morbidity and mortality. Anti-C5 monoclonal antibodies (aC5-mab) are standard treatments, but large studies and long-term data are scarce. Here, we report our single institution experience to augment the knowledge of CM-TMA treated with aC5-mab therapy. METHODS: We aimed to assess the short and long-term effects of aC5-mab in patients diagnosed with CM-TMA treated outside of a clinical trial. This was a retrospective study. We included all patients diagnosed with CM-TMA and treated with aC5-mab at our institution. There were no exclusion criteria. Endpoints included complete TMA response (CR) defined as normalization of hematological parameters and ≥25% improvement in serum creatinine (Cr) from baseline in patients with renal disease, relapse defined as losing the previously achieved CR, morbidity, adverse events, and survival. RESULTS: We found 28 patients with CM-TMA treated with aC5-mab. The median age was 50 years. Baseline laboratories: platelet counts 93 × 109 /L, hemoglobin 8.6 g/dL, lactate dehydrogenase 1326 U/L, serum Cr 4.7 mg/dL, and estimated glomerular filtration rate 19 mL/min. One individual was on renal replacement therapy (RRT) and 10 initiated RRT within 5 days of the first dose of aC5-mab. Genetic variants associated with CM-TMA included mutations in C3, CFB, CFH, CFHR1/3, CFI, and MCP. The mean duration of hospitalization was 24 days. The median time to initiation of aC5-mab was 10 days. Sixteen subjects received RRT. At the time of hospital discharge, 27 were alive, 14 remained on RRT, and 4 had a CR. At 6 months, 23 patients were alive, 18 continued aC5-mab, 8 remained on RRT, and 9 had a CR. At the last follow-up visit past 6 months, 20 were alive, 14 continued aC5-mab, 5 remained on RRT, 12 had a CR, and 1 was lost to follow-up. CONCLUSIONS: Our study provides real-world experience and insight into the long-term outcomes of CM-TMA treated with aC5-mab. Our findings validate that CM-TMA is an aggressive disease with significant morbidity and mortality, and confirm that aC5-mab is a relatively effective therapy for CM-TMA. Our study adds practical, real-world experience to the literature, but future research remains imperative.
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Síndrome Hemolítico-Urêmica Atípica , Proteínas Inativadoras do Complemento , Microangiopatias Trombóticas , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/tratamento farmacológico , Microangiopatias Trombóticas/etiologia , Síndrome Hemolítico-Urêmica Atípica/tratamento farmacológico , Síndrome Hemolítico-Urêmica Atípica/genética , Proteínas do Sistema ComplementoRESUMO
Thrombotic microangiopathy (TMA), characterized by microangiopathic hemolytic anemia, thrombocytopenia, and multisystem organ dysfunction, is a life-threatening disease. Patients with TMA who do not exhibit a severe ADAMTS-13 deficiency (defined as a disintegrin-like and metalloprotease with thrombospondin type 1 motif no. 13 activity ≥10%: TMA-13n) continue to experience elevated mortality rates. This study explores the prognostic indicators for augmented mortality risk or necessitating chronic renal replacement therapy (composite outcome: CO) in TMA-13n patients. We included 42 TMA-13n patients from January 2008 to May 2018. Median age of 41 years and 60% were female. At presentation, 62% required dialysis, and 57% warranted intensive care unit admission. CO was observed in 45% of patients, including a 9-patient mortality subset. Multivariate logistic regression revealed three independent prognostic factors for CO: early administration of eculizumab (median time from hospitalization to eculizumab initiation: 5 days, range 0-19 days; odds ratio [OR], 0.14; 95% confidence interval [CI], 0.02-0.94), presence of neuroradiological lesions (OR, 6.67; 95% CI, 1.12-39.80), and a PLASMIC score ≤4 (OR, 7.39; 95% CI, 1.18-46.11). In conclusion, TMA-13n patients exhibit a heightened risk of CO in the presence of low PLASMIC scores and neuroradiological lesions, while early eculizumab therapy was the only protective factor.
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BACKGROUND: Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder that is characterized by quotidian fevers, arthritis, and an evanescent rash. Occurrence of concurrent thrombotic microangiopathy (TMA) in AOSD is rare. The treatment aspects of TMA in AOSD are actively being debated. METHODS: Medline search using MeSH terms and snowballing yielded a total of 29 articles with co-occurrence of AOSD and thrombotic thrombocytopenic purpura (TTP) including our own. Pooled data were synthesized for descriptive analysis. RESULTS: Median age was 35 years with a majority of females (68.96%). A majority of these studies/patients were either Asian (34.48%) or Caucasian (31.03%). Concurrent TMA at the time of AOSD diagnosis was seen in 65.51% patients. Only 3/29 patients had ADAMTS13 level less than 10%, consistent with TTP and 3/29 were diagnosed with hemolytic uremic syndrome (HUS). The remainder were diagnosed clinically. Complication rate was high, and 15/29 (51.72%) patients died or had permanent neurological/renal/vision/gangrenous complications. Median and mean ferritin peak was observed to be higher (7458 and 12 349, respectively) in patients who either died/had partial remission, compared to those who had complete response (3257 and 10 899, respectively), p = .829. CONCLUSIONS: A majority of patients with AOSD-associated TMA either died or had permanent complications. TMA was diagnosed alongside AOSD in 65% patients, while the rest developed TMA during the course of their disease. Blurred vision may precede TMA and could help risk-stratify high-risk AOSD patients clinically. Glycosylated ferritin remains low several weeks to months after disease remission and may be used to monitor severity of disease process. Further studies are necessary to confirm the existing vascular endothelial growth factor hypothesis in AOSD-associated TMA.
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Síndrome Hemolítico-Urêmica , Púrpura Trombocitopênica Trombótica , Doença de Still de Início Tardio , Microangiopatias Trombóticas , Adulto , Feminino , Humanos , Púrpura Trombocitopênica Trombótica/complicações , Púrpura Trombocitopênica Trombótica/diagnóstico , Doença de Still de Início Tardio/complicações , Doença de Still de Início Tardio/diagnóstico , Doença de Still de Início Tardio/terapia , Fator A de Crescimento do Endotélio Vascular , Microangiopatias Trombóticas/complicações , Microangiopatias Trombóticas/diagnóstico , Síndrome Hemolítico-Urêmica/complicações , Síndrome Hemolítico-Urêmica/diagnóstico , Síndrome Hemolítico-Urêmica/terapiaRESUMO
OBJECTIVES: To describe late transplant-associated thrombotic microangiopathy (TA-TMA) as chronic endothelial complication in bone marrow (BM) after allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: BM specimens along with conventional diagnostic parameters were assessed in 14 single-institutional patients with late TA-TMA (more than 100 days after HCST), including 11 late with history of early TA-TMA, 10 with early TA-TMA (within 100 days), and 12 non TA-TMA patients. Three non-HSCT patients served as control. The time points of BM biopsy were +1086, +798, +396, and +363 days after HSCT, respectively. RESULTS: Late TA-TMA patients showed an increase of CD34+ and von Willebrand Factor (VWF)+ microvascular endothelial cells with atypical VWF+ conglomerates forming thickened VWF+ plaque sinus in the BM compared to patients without late TA-TMA and non-HSCT. Severe chronic (p = .002), steroid-refractory GVHD (p = .007) and reactivation of HHV6 (p = .002), EBV (p = .003), and adenovirus (p = .005) were pronounced in late TA-TMA. Overall and relapse-free survival were shorter in late TA-TMA than in patients without late TA-TMA (5-year OS and RFS: 78.6% vs. 90.2%, 71.4% vs. 86.4%, respectively). CONCLUSION: Chronic allo-immune microangiopathy in BM associated with chronic, steroid-refractory GVHD and/or viral infections are key findings of late, high-risk TA-TMA, which deserves clinical attention.
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Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Microangiopatias Trombóticas , Viroses , Humanos , Medula Óssea/patologia , Células Endoteliais/patologia , Fator de von Willebrand , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/terapia , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Viroses/complicações , Biópsia , EsteroidesRESUMO
As the number of patients living with kidney failure grows, the need also grows for kidney transplantation, the gold standard kidney replacement therapy that provides a survival advantage. This may result in an increased rate of transplantation from HLA-mismatched donors that increases the rate of antibody-mediated rejection (AMR), which already is the leading cause of allograft failure. Plasmapheresis, intravenous immunoglobulin therapy, anti-CD20 therapies (i.e., rituximab), bortezomib and splenectomy have been used over the years to treat AMR as well as to prevent AMR in high-risk sensitized kidney transplant recipients. Eculizumab and ravulizumab are monoclonal antibodies targeting the C5 protein of the complement pathway and part of the expanding field of anticomplement therapies, which is not limited to kidney transplant recipients, and also includes complement-mediated microangiopathic hemolytic anemia, paroxysmal nocturnal hemoglobinuria, and ANCA-vasculitis. In this narrative review, we summarize the current knowledge concerning the pathophysiological background and use of anti-C5 strategies (eculizumab and ravulizumab) and C1-esterase inhibitor in AMR, either to prevent AMR in high-risk desensitized patients or to treat AMR as first-line or rescue therapy and also to treat de novo thrombotic microangiopathy in kidney transplant recipients.
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Proteínas Inativadoras do Complemento , Transplante de Rim , Rim , Humanos , Transplante Homólogo , Transplante de Rim/efeitos adversos , Aloenxertos , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controleRESUMO
Atypical hemolytic uremic syndrome (aHUS) is a complement-mediated thrombotic microangiopathy sometimes associated with germline variants in genes of the complement system. Clinical findings of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury arise due to aberrant complement protein activation in the circulation. A 13-month-old boy with metastatic neuroblastoma (NB) developed aHUS during his first cycle of induction chemotherapy with germline testing revealing a complement factor H (CFH) gene mutation, currently classified as a variant of uncertain significance (VUS). Now he is in disease remission after successful complement blockade therapy, thus highlighting a unique presentation of aHUS in a patient with newly diagnosed NB.
Assuntos
Síndrome Hemolítico-Urêmica Atípica , Quimioterapia de Indução , Neuroblastoma , Humanos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Neuroblastoma/genética , Masculino , Síndrome Hemolítico-Urêmica Atípica/tratamento farmacológico , Síndrome Hemolítico-Urêmica Atípica/genética , Síndrome Hemolítico-Urêmica Atípica/patologia , Quimioterapia de Indução/efeitos adversos , Lactente , Fator H do Complemento/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mutação em Linhagem GerminativaRESUMO
De novo thrombotic microangiopathy (TMA) is a rare and challenging condition in kidney transplant recipients, with limited research on its incidence and impact on graft survival. This study conducted a systematic review and meta-analysis of 28 cohorts/single-arm studies and 46 case series/reports from database inception to June 2022. In meta-analysis, among 14,410 kidney allograft recipients, de novo TMA occurred in 3.20% [95% confidence interval (CI): 1.93-4.77], with systemic and renal-limited TMA rates of 1.38% (95% CI: 06.5-2.39) and 2.80% (95% CI: 1.27-4.91), respectively. The overall graft loss rate of de novo TMA was 33.79% (95% CI: 26.14-41.88) in meta-analysis. This study provides valuable insights into the incidence and graft outcomes of de novo TMA in kidney transplant recipients.
Assuntos
Sobrevivência de Enxerto , Transplante de Rim , Microangiopatias Trombóticas , Humanos , Incidência , Rim , Microangiopatias Trombóticas/complicaçõesRESUMO
Thrombocytopenia frequently occurs in patients with sepsis. Disseminated intravascular coagulation (DIC) may be a possible cause of thrombocytopenia owing to its high prevalence and association with poor outcomes; however, it is important to keep the presence of other diseases in mind in sepsis practice. Thrombotic microangiopathy (TMA), which is characterized by thrombotic thrombocytopenic purpura, Shiga toxin-producing Escherichia coli hemolytic uremic syndrome (HUS), and complement-mediated HUS, is characterized by thrombocytopenia, microangiopathic hemolytic anemia, and organ damage. TMA has become widely recognized in recent years because of the development of specific treatments. Previous studies have reported a remarkably lower prevalence of TMA than DIC; however, its epidemiology is not well defined, and there may be cases in which TMA is not correctly diagnosed, resulting in poor outcomes. Therefore, it is important to differentiate DIC from TMA. Nevertheless, differentiating between DIC and TMA remains a challenge as indicated by previous reports that most patients with TMA can be diagnosed as DIC using the universal coagulation scoring system. Several algorithms to differentiate sepsis-related DIC from TMA have been suggested, contributing to improving the care of septic patients with thrombocytopenia; however, it may be difficult to apply these algorithms to patients with coexisting DIC and TMA, which has recently been reported. This review describes the disease characteristics, including epidemiology, pathophysiology, and treatment, of DIC, TMA, and other diseases with thrombocytopenia and proposes a novel practical approach flow, which is characterized by the initiation of the diagnosis of TMA in parallel with the diagnosis of DIC. This practical flow also refers to the longitudinal diagnosis and treatment flow with TMA in mind and real clinical timeframes. In conclusion, we aim to widely disseminate the results of this review that emphasize the importance of incorporating consideration of TMA in the management of septic DIC. We anticipate that this practical new approach for the diagnostic and treatment flow will lead to the appropriate diagnosis and treatment of complex cases, improve patient outcomes, and generate new epidemiological evidence regarding TMA.
RESUMO
INTRODUCTION: Allograft dysfunction within the first week posttransplant is an uncommon but known complication following liver transplantation. Seventh-Day Syndrome (7DS) is a rare complication of allograft dysfunction following liver transplantation characterized by the rapid clinical deterioration of a formerly well-functioning allograft within the first week posttransplant. The etiology of 7DS is unknown, and treatment options remain limited. While cases of graft survival have been reported, the risk of mortality remains exceedingly high without urgent retransplantation. METHODS: Patient data was retrospectively analyzed and a literature review performed. RESULTS: We present a unique case of split liver transplantation into two pediatric recipients in which one recipient developed rapidly progressive graft failure approximately 1 week postoperatively requiring urgent retransplantation while the other recipient had an unremarkable postoperative course. Upon clinical manifestation of progressive graft failure, the patient was treated with thymoglobulin, rituximab, intravenous immunoglobulin, and plasmapheresis. Despite this, the patient's clinical status continued to decline and she underwent retransplantation 11 days following her initial liver transplant. CONCLUSION: Seventh-Day Syndrome is a rare complication following liver transplantation that is associated with a high risk of morbidity and mortality. Our case adds to the limited literature on 7DS in children and is the first to report a comparative posttransplant clinical course in two recipients who received split grafts from the same donor.