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OBJECTIVE: Haemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening systemic hyperinflammatory syndromes that can develop in most inflammatory contexts. They can progress rapidly, and early identification and management are critical for preventing organ failure and mortality. This effort aimed to develop evidence-based and consensus-based points to consider to assist clinicians in optimising decision-making in the early stages of diagnosis, treatment and monitoring of HLH/MAS. METHODS: A multinational, multidisciplinary task force of physician experts, including adult and paediatric rheumatologists, haematologist/oncologists, immunologists, infectious disease specialists, intensivists, allied healthcare professionals and patients/parents, formulated relevant research questions and conducted a systematic literature review (SLR). Delphi methodology, informed by SLR results and questionnaires of experts, was used to generate statements aimed at assisting early decision-making and optimising the initial care of patients with HLH/MAS. RESULTS: The task force developed 6 overarching statements and 24 specific points to consider relevant to early recognition of HLH/MAS, diagnostic approaches, initial management and monitoring of HLH/MAS. Major themes included the simultaneous need for prompt syndrome recognition, systematic evaluation of underlying contributors, early intervention targeting both hyperinflammation and likely contributors, careful monitoring for progression/complications and expert multidisciplinary assistance. CONCLUSION: These 2022 EULAR/American College of Rheumatology points to consider provide up-to-date guidance, based on the best available published data and expert opinion. They are meant to help guide the initial evaluation, management and monitoring of patients with HLH/MAS in order to halt disease progression and prevent life-threatening immunopathology.
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Linfo-Histiocitose Hemofagocítica , Síndrome de Ativação Macrofágica , Reumatologia , Criança , Adulto , Humanos , Estados Unidos , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/terapia , Linfo-Histiocitose Hemofagocítica/etiologia , Síndrome de Ativação Macrofágica/diagnóstico , Síndrome de Ativação Macrofágica/etiologia , Síndrome de Ativação Macrofágica/terapia , ConsensoRESUMO
OBJECTIVE: Haemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening systemic hyperinflammatory syndromes that can develop in most inflammatory contexts. They can progress rapidly, and early identification and management are critical for preventing organ failure and mortality. This effort aimed to develop evidence-based and consensus-based points to consider to assist clinicians in optimising decision-making in the early stages of diagnosis, treatment and monitoring of HLH/MAS. METHODS: A multinational, multidisciplinary task force of physician experts, including adult and paediatric rheumatologists, haematologist/oncologists, immunologists, infectious disease specialists, intensivists, allied healthcare professionals and patients/parents, formulated relevant research questions and conducted a systematic literature review (SLR). Delphi methodology, informed by SLR results and questionnaires of experts, was used to generate statements aimed at assisting early decision-making and optimising the initial care of patients with HLH/MAS. RESULTS: The task force developed 6 overarching statements and 24 specific points to consider relevant to early recognition of HLH/MAS, diagnostic approaches, initial management and monitoring of HLH/MAS. Major themes included the simultaneous need for prompt syndrome recognition, systematic evaluation of underlying contributors, early intervention targeting both hyperinflammation and likely contributors, careful monitoring for progression/complications and expert multidisciplinary assistance. CONCLUSION: These 2022 EULAR/American College of Rheumatology points to consider provide up-to-date guidance, based on the best available published data and expert opinion. They are meant to help guide the initial evaluation, management and monitoring of patients with HLH/MAS in order to halt disease progression and prevent life-threatening immunopathology.
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Linfo-Histiocitose Hemofagocítica , Síndrome de Ativação Macrofágica , Médicos , Adulto , Criança , Humanos , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/terapia , Síndrome de Ativação Macrofágica/diagnóstico , Síndrome de Ativação Macrofágica/etiologia , Síndrome de Ativação Macrofágica/terapia , Consenso , Comitês ConsultivosRESUMO
OBJECTIVE: To provide guidance to rheumatology providers on the management of adult rheumatic disease in the context of the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A task force, including 10 rheumatologists and 4 infectious disease specialists from North America, was convened. Clinical questions were collated, and an evidence report was rapidly generated and disseminated. Questions and drafted statements were reviewed and assessed using a modified Delphi process. This included asynchronous anonymous voting by email and webinars with the entire panel. Task force members voted on agreement with draft statements using a 1-9-point numerical scoring system, and consensus was determined to be low, moderate, or high based on the dispersion of votes. For approval, median votes were required to meet predefined levels of agreement (median values of 7-9, 4-6, and 1-3 defined as agreement, uncertainty, or disagreement, respectively) with either moderate or high levels of consensus. RESULTS: Draft guidance statements approved by the task force have been combined to form final guidance. CONCLUSION: These guidance statements are provided to promote optimal care during the current pandemic. However, given the low level of available evidence and the rapidly evolving literature, this guidance is presented as a "living document," and future updates are anticipated.
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Antirreumáticos/uso terapêutico , COVID-19/prevenção & controle , Glucocorticoides/administração & dosagem , Imunossupressores/uso terapêutico , Doenças Reumáticas/terapia , Comitês Consultivos , COVID-19/complicações , Consenso , Tomada de Decisão Compartilhada , Atenção à Saúde , Técnica Delphi , Desprescrições , Gerenciamento Clínico , Humanos , Educação de Pacientes como Assunto , Doenças Reumáticas/complicações , Reumatologia , SARS-CoV-2 , Sociedades MédicasRESUMO
OBJECTIVES: Patients with lupus membranous nephropathy (LMN) are at risk for prolonged proteinuria and progressive chronic kidney disease. There are no proven effective treatments for LMN, and controlled trials are lacking. This trial assessed the preferential Janus kinase 1 (JAK1) inhibitor filgotinib and the spleen tyrosine kinase inhibitor lanraplenib in patients with LMN. METHODS: This was a phase II, randomised, double-blind trial conducted at 15 centres in the USA to evaluate the safety and efficacy of filgotinib or lanraplenib for the treatment of LMN. Eligible patients were randomised 1:1 to receive either filgotinib or lanraplenib in a blinded fashion for up to 52 weeks. The primary endpoint was the per cent change in 24-hour urine protein from baseline to week 16. RESULTS: Nine patients were randomised to receive filgotinib (n=5) or lanraplenib (n=4). Four patients in the filgotinib group and one patient in the lanraplenib group completed week 16. There was a median reduction of 50.7% in 24-hour urine protein after 16 weeks of treatment with filgotinib (n=4), and the median Systemic Lupus Erythematosus Disease Activity Index from the Safety of Estrogens in Lupus National Assessment score remained stable. Filgotinib treatment was well tolerated. Limited conclusions can be drawn about treatment with lanraplenib. CONCLUSION: The number of patients treated in this study was small, and only limited conclusions can be drawn. There may be a therapeutic benefit with filgotinib treatment, which may support future investigations with filgotinib or other JAK inhibitors in patients with LMN. TRIAL REGISTRATION NUMBER: NCT03285711.
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Glomerulonefrite Membranosa , Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Piridinas , TriazóisRESUMO
OBJECTIVE: To provide guidance to rheumatology providers on the management of adult rheumatic disease in the context of the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A task force, including 10 rheumatologists and 4 infectious disease specialists from North America, was convened. Clinical questions were collated, and an evidence report was rapidly generated and disseminated. Questions and drafted statements were reviewed and assessed using a modified Delphi process. This included asynchronous anonymous voting by e-mail and webinars with the entire panel. Task force members voted on agreement with draft statements using a 1-9-point numerical scoring system, and consensus was determined to be low, moderate, or high based on the dispersion of votes. For approval, median votes were required to meet predefined levels of agreement (median values of 7-9, 4-6, and 1-3 defined as agreement, uncertainty, or disagreement, respectively) with either moderate or high levels of consensus. RESULTS: To date, the task force has approved 80 guidance statements: 36 with moderate and 44 with high consensus. These were combined, resulting in 27 final guidance statements. CONCLUSION: These guidance statements are provided to promote optimal care during the current pandemic. However, given the low level of available evidence and the rapidly evolving literature, this guidance is presented as a "living document," and future updates are anticipated.
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Antirreumáticos/uso terapêutico , COVID-19 , Doenças Reumáticas/tratamento farmacológico , Adulto , Humanos , Pandemias , Estados UnidosRESUMO
OBJECTIVE: To provide guidance to rheumatology providers on the management of adult rheumatic disease in the context of the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A task force, including 10 rheumatologists and 4 infectious disease specialists from North America, was convened. Clinical questions were collated, and an evidence report was rapidly generated and disseminated. Questions and drafted statements were reviewed and assessed using a modified Delphi process. This included 2 rounds of asynchronous anonymous voting by e-mail and 3 webinars with the entire panel. Task force members voted on agreement with draft statements using a 1-9-point numerical scoring system, and consensus was determined to be low, moderate, or high based on the dispersion of votes. For approval, median votes were required to meet predefined levels of agreement (median values of 7-9, 4-6, and 1-3 defined as agreement, uncertainty, or disagreement, respectively) with either moderate or high levels of consensus. RESULTS: The task force approved 77 initial guidance statements: 36 with moderate and 41 with high consensus. These were combined, resulting in 25 final guidance statements. CONCLUSION: These guidance statements are provided to promote optimal care during the current pandemic. However, given the low level of available evidence and the rapidly evolving literature, this guidance is presented as a "living document," and future updates are anticipated.
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Antirreumáticos/uso terapêutico , Infecções por Coronavirus/epidemiologia , Glucocorticoides/uso terapêutico , Imunossupressores/uso terapêutico , Pneumonia Viral/epidemiologia , Doenças Reumáticas/tratamento farmacológico , Adulto , Comitês Consultivos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Betacoronavirus , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/prevenção & controle , Atenção à Saúde , Técnica Delphi , Desprescrições , Humanos , Hidroxicloroquina/uso terapêutico , Controle de Infecções , Inibidores de Janus Quinases/uso terapêutico , Pandemias/prevenção & controle , Pneumonia Viral/complicações , Pneumonia Viral/prevenção & controle , Doenças Reumáticas/complicações , Reumatologia , SARS-CoV-2 , Inibidores do Fator de Necrose Tumoral/uso terapêuticoRESUMO
OBJECTIVE: To determine the frequency, characteristics, and outcomes of cerebrovascular events (CerVEs), as well as clinical and autoantibody associations in a multiethnic/racial inception cohort of patients with systemic lupus erythematosus (SLE). METHODS: A total of 1,826 patients were assessed annually for 19 neuropsychiatric (NP) events, including 5 types of CerVEs: 1) stroke, 2) transient ischemia, 3) chronic multifocal ischemia, 4) subarachnoid/intracranial hemorrhage, and 5) sinus thrombosis. Global disease activity (Systemic Lupus Erythematosus Disease [SLE] Activity Index 2000), damage scores (SLE International Collaborating Clinics/American College of Rheumatology Damage Index), and Short Form 36 (SF-36) scores were collected. Time to event, linear and logistic regressions, and multistate models were used as appropriate. RESULTS: CerVEs were the fourth most frequent NP event: 82 of 1,826 patients had 109 events; of these events, 103 were attributed to SLE, and 44 were identified at the time of enrollment. The predominant events were stroke (60 of 109 patients) and transient ischemia (28 of 109 patients). CerVEs were associated with other NP events attributed to SLE, non-SLE-attributed NP events, African ancestry (at US SLICC sites), and increased organ damage scores. Lupus anticoagulant increased the risk of first stroke and sinus thrombosis and transient ischemic attack. Physician assessment indicated resolution or improvement in the majority of patients, but patients reported sustained reduction in SF-36 summary and subscale scores following a CerVE. CONCLUSION: CerVEs, the fourth most frequent NP event in SLE, are usually attributable to lupus. In contrast to good physician-reported outcomes, patients reported a sustained reduction in health-related quality of life following a CerVE.
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Transtornos Cerebrovasculares/imunologia , Lúpus Eritematoso Sistêmico/complicações , Adulto , Transtornos Cerebrovasculares/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Adulto JovemRESUMO
BACKGROUND: Medication decision-making poses a challenge for a significant proportion of patients. This is an even more challenging for patients who have complex, rare, immune conditions that affect them at a young age and are associated with the use of life-long treatment, perceived by some as having significant risk of side effects and toxicity. INTRODUCTION: The aim of our study was to examine the perspectives of women with lupus nephritis on facilitators to medication decision-making. METHODS: We used the nominal group technique (NGT), a structured formative process to elicit patient perspectives. An NGT expert moderated eight patient group meetings. Participants (n = 52) responded to the question "What sorts of things make it easier for people to decide to take the medicines that doctors prescribe for treating their lupus kidney disease?" Patients nominated, discussed, and prioritized facilitators to medication decisional processes. RESULTS: Fifty-two women with lupus nephritis participated in eight NGT meetings (27 African-American, 13 Hispanic, and 12 Caucasian). Average age was 40.6 years (standard deviation (SD) = 13.3), and disease duration was 11.8 years (SD = 8.3); 36.5 % obtained at least a college education, and 55.8 % had difficulty in reading health materials. Patients generated 280 decision-making facilitators (range of 26 to 42 per panel). Of these, 102 (36 %) facilitators were perceived by patients as having relatively more influence in decision-making processes than others. Prioritized facilitators included effective patient-physician communication regarding benefits/harms, patient desire to live a normal life and improve quality of life, concern for their dependents, experiencing benefits and few/infrequent/no harms with lupus medications, and their affordability. Relative to African-Americans, Caucasian and Hispanic patients endorsed a smaller percentage of facilitators as influential. Level of agreement with which patients within panels independently agreed in their selections of the three most influential facilitators ranged from 33 % to 60 %. CONCLUSIONS: We identified facilitators to lupus medication decision-making. This information will be used to populate a decision aid for lupus nephritis.
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Tomada de Decisões , Tratamento Farmacológico/psicologia , Nefrite Lúpica/tratamento farmacológico , Participação do Paciente/psicologia , Adulto , Negro ou Afro-Americano , Feminino , Hispânico ou Latino , Humanos , Nefrite Lúpica/etnologia , Pessoa de Meia-Idade , Relações Médico-Paciente , Qualidade de Vida , Inquéritos e Questionários , População BrancaRESUMO
OBJECTIVE: To assess the perspectives of women with lupus nephritis on barriers to medication decision making. METHODS: We used the nominal group technique (NGT), a structured process to elicit ideas from participants, for a formative assessment. Eight NGT meetings were conducted in English and moderated by an expert NGT researcher at 2 medical centers. Participants responded to the question: "What sorts of things make it hard for people to decide to take the medicines that doctors prescribe for treating their lupus kidney disease?" Patients nominated, discussed, and prioritized barriers to decisional processes involving medications for treating lupus nephritis. RESULTS: Fifty-one women with lupus nephritis with a mean age of 40.6 ± 13.3 years and disease duration of 11.8 ± 8.3 years participated in 8 NGT meetings: 26 African Americans (4 panels), 13 Hispanics (2 panels), and 12 whites (2 panels). Of the participants, 36.5% had obtained at least a college degree and 55.8% needed some help in reading health materials. Of the 248 responses generated (range 19-37 responses/panel), 100 responses (40%) were perceived by patients as having relatively greater importance than other barriers in their own decision-making processes. The most salient perceived barriers, as indicated by percent-weighted votes assigned, were known/anticipated side effects (15.6%), medication expense/ability to afford medications (8.2%), and the fear that the medication could cause other diseases (7.8%). CONCLUSION: Women with lupus nephritis identified specific barriers to decisions related to medications. Information relevant to known/anticipated medication side effects and medication cost will form the basis of a patient guide for women with systemic lupus erythematosus, currently under development.
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Tomada de Decisão Clínica , Conhecimentos, Atitudes e Prática em Saúde , Nefrite Lúpica/tratamento farmacológico , Participação do Paciente , Adulto , Idoso , Feminino , Humanos , Nefrite Lúpica/psicologia , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: To present a case of human monocytic ehrlichiosis (HME) that was complicated by macrophage activation syndrome (MAS), also known as secondary hemophagocytic lymphohistiocytosis (sHLH). METHODS: Data was collected from patient's electronic medical records at the University of Alabama at Birmingham. The patient is a part of a larger cohort of patients with all-cause MAS treated at our center. CASE: A 63 year old renal transplant recipient male on maintenance immunosuppressive therapy presented with high grade fever, leukopenia, thrombocytopenia and elevated transaminases and initially met clinical criteria for severe sepsis. On further investigation, clinical and laboratory criteria for MAS were met. He was treated with a combination of doxycycline for HME and a novel combination of anakinra (interleukin-1 receptor antagonist), and high dose corticosteroids. The discussion focuses on clinical presentation, pathogenesis and treatment of MAS with an emphasis on MAS secondary to HME. CONCLUSION: Macrophage activation syndrome or sHLH is a dysfunctional, hyperactive and potentially fatal immune system response that results in multi-organ dysfunction. With increasing incidence of Ehrlichia chaffeensis as an emerging pathogen, clinicians should be aware of this fulminant and potentially fatal complication of HME.
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PURPOSE OF REVIEW: Sarcoidosis commonly involves the lungs but also not uncommonly presents as uveitis, arthritis, myositis or neurologic disease. Recognition of the presenting features, organ complications, and immunopathogenesis is important for timely diagnosis and appropriate management. RECENT FINDINGS: Current studies support the disorder developing as a consequence of a CD4+ T-cell-mediated response to variable environmental or microbial triggers in the context of one or more determined susceptibility genes including BTNL2, with other genes such as CARD15/NOD2, governing disease severity. Magnetic resonance imaging (MRI) is useful in defining the presence and extent of central nervous system (CNS), osseous, and both skeletal and cardiac muscle disease. Corticosteroids remain the mainstay of therapy; patients with refractory disease may respond to other immunomodulating drugs, including anti-TNF-alpha antibodies but the optimal roles of traditional immunomodulating as well as newer biologic therapies in management are continuing to be defined. SUMMARY: Insights into triggering immune events and susceptibility genes should provide potential new strategies and targets for therapy. The judicious use of MRI in suspected cases can enhance earlier recognition of disease in the CNS, bone, and both skeletal and cardiac muscle to guide diagnostic procedures as well as appropriate treatment.
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Autoimunidade/genética , Autoimunidade/imunologia , Predisposição Genética para Doença/genética , Sarcoidose/genética , Sarcoidose/imunologia , Butirofilinas , Diagnóstico Precoce , Humanos , Imunidade Celular/genética , Imunidade Celular/imunologia , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Imageamento por Ressonância Magnética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Valor Preditivo dos Testes , Sarcoidose/fisiopatologiaRESUMO
INTRODUCTION: This trial evaluated the safety, biologic activity, and pharmacokinetics of belimumab, a fully human monoclonal antibody that inhibits the biologic activity of the soluble form of the essential B-cell survival factor B-lymphocyte stimulator (BLyS) in patients with systemic lupus erythematosus (SLE). METHODS: Seventy patients with mild-to-moderate SLE were enrolled in a phase I, double-blind, randomized study and treated with placebo (n = 13) or belimumab (n = 57) at four different doses (1.0, 4.0, 10, and 20 mg/kg) as a single infusion or two infusions 21 days apart. Patients were followed for 84 to 105 days to assess adverse events, pharmacokinetics, peripheral blood B-cell counts, serology, and SLE disease activity. Data from the study were summarized using descriptive statistics. chi2 type tests were used to analyze discrete variables. The Kruskal-Wallis test, the Wilcoxon test, and the analysis of covariance were used to analyze the continuous variables, as appropriate. The analysis was performed on all randomized patients who received study agent. RESULTS: The incidences of adverse events and laboratory abnormalities were similar among the belimumab and placebo groups. Belimumab pharmacokinetics were linear across the 1.0 to 20 mg/kg dose range. Long terminal elimination half-life (8.5 to 14.1 days), slow clearance (7 ml/day per kg), and small volume of distribution (69 to 112 ml/kg) were consistent with a fully human antibody. Significant reductions in median percentages of CD20+ B cells were observed in patients treated with a single dose of belimumab versus placebo (day 42: P = 0.0042; and day 84: P = 0.0036) and in patients treated with two doses of belimumab versus placebo (day 105: P = 0.0305). SLE disease activity did not change after one or two doses of belimumab. CONCLUSIONS: Belimumab was well tolerated and reduced peripheral B-cell levels in SLE patients. These data support further studies of belimumab in autoimmune disorders.
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Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Fator Ativador de Células B/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/efeitos dos fármacos , Anticorpos Monoclonais Humanizados , Fator Ativador de Células B/imunologia , Linfócitos B/efeitos dos fármacos , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To determine the association of plasma B lymphocyte stimulator (BLyS) levels, immunosuppressive therapy, and other clinical parameters with disease activity in systemic lupus erythematosus (SLE). METHODS: Two hundred forty-five SLE patients were evaluated prospectively over a 2-year period at 4 centers. Assessments were performed every 3-6 months. Univariate analysis was used to determine the association among the Safety of Estrogens in Lupus Erythematosus: National Assessment (SELENA) version of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, serum anti-double-stranded DNA (anti-dsDNA), and plasma BLyS levels. A multivariate repeated-measures model incorporating immunosuppressive therapy was utilized. RESULTS: Ninety-two percent of the patients were female. Sixty-seven percent were white, 31% African American, and 2% Asian (all of these groups may include Hispanic). Mean values at baseline were as follows: age 41.5 years, disease duration 8.1 years, SELENA-SLEDAI 3.3 (median 2, range 0-18), BLyS 5.57 ng/ml, IgG 1,439 mg/dl, C3 104.4 mg/dl, and C4 21.3 mg/dl; among those positive for anti-dsDNA, the median titer was 1:40 (range 1:10-1:1,280). Univariate analysis showed that plasma BLyS levels were associated with anti-dsDNA titers (P = 0.0465) and SELENA-SLEDAI scores (P = 0.0002). In multivariate analyses, a greater increase in the SELENA-SLEDAI score from the previous visit was associated with higher BLyS levels at the previous visit (P = 0.0042) and with a greater increase in the BLyS level from the previous visit (P = 0.0007). CONCLUSION: The findings of association between a greater increase in the BLyS level from the previous visit and a greater increase in the SELENA-SLEDAI score at the subsequent visit, and between an elevated BLyS level at the previous visit and a greater SELENA-SLEDAI score at the subsequent visit, demonstrate a relationship between circulating BLyS levels and SLE disease activity. These results lend support to the notion that BLyS is a candidate for therapeutic targeting in SLE.
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Fator Ativador de Células B/sangue , Lúpus Eritematoso Sistêmico/sangue , Índice de Gravidade de Doença , Adulto , Biomarcadores/sangue , Feminino , Humanos , Imunoglobulinas/sangue , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos ProspectivosRESUMO
OBJECTIVE: To determine whether receptors for B lymphocyte stimulator (BLyS) are altered on B cells of patients with systemic lupus erythematosus (SLE). METHODS: Total available receptors for BLyS were measured by analysis of binding of recombinant soluble BLyS to peripheral blood B cells in 36 SLE patients, 29 healthy controls, and 10 disease controls. Antibodies to the receptors BAFF-R, BCMA, and TACI were used to define expression of the individual BLyS receptors on subsets of B cells in blood, spleen, and tonsils. Two different antibodies to BAFF-R, which were differentially sensitive to BAFF-R occupancy, were used to compare BAFF-R on B cells in an additional 20 healthy subjects and 25 SLE patients. Assays of B cell survival after stimulation in vitro were used to determine the sensitivity of B cells to exogenous BLyS. RESULTS: Total available receptors for BLyS were decreased in patients with SLE, independent of changes of subsets in the blood in these patients. The decrease correlated with changes in disease activity. Although total surface BAFF-R was not significantly different between healthy controls and SLE patients, BAFF-R was occupied in SLE patients. B cells from these patients were less responsive to exogenous BLyS. CONCLUSION: BAFF-R is consistently occupied on blood B cells in SLE. Occupancy of BAFF-R on blood B cells is likely to contribute to disease mechanisms in SLE and could serve as a biomarker of disease activity. Targeting BLyS as a therapeutic strategy will require overcoming the persistent binding of BLyS to BAFF-R.
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Linfócitos B/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Receptores do Fator de Necrose Tumoral/imunologia , Receptores do Fator de Necrose Tumoral/metabolismo , Adulto , Anticorpos Monoclonais , Receptor do Fator Ativador de Células B , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Antineutrophil cytoplasmic Abs (ANCA) can activate neutrophils in an FcgammaR-dependent manner, but the link between this ANCA-induced effect and mononuclear cell activation with the characteristic granuloma formation of Wegener's granulomatosis is unclear. Human alpha-defensins, small cationic antimicrobial peptides, are found in neutrophils and have chemotactic activity for T cells, dendritic cells, and monocytes. In this study, we quantitated the release of alpha-defensins (human neutrophil peptides 1-3) from human neutrophils after targeted FcgammaR cross-linking (XL). Homotypic XL of FcgammaRIIa, FcgammaRIIIb, or heterotypic XL of both receptors resulted in significant release of alpha-defensins, an effect also induced by both human polyclonal and murine monoclonal cytoplasmic staining ANCA (anti-proteinase 3). This release of alpha-defensins, as well as of other granule constituents (ANCA targets anti-proteinase 3 and myeloperoxidase and elastase), was significantly greater in donors homozygous for the NA1 allele of FcgammaRIIIb than in donors homozygous for NA2. Interestingly, the ANCA-induced release was completely inhibited by the IgG Fc-binding peptide TG19320, which blocks the IgG-Fc region from binding to FcgammaR. Based on their chemotactic properties, alpha-defensins and their release by ANCA may contribute to modulation of the acquired immune response and to granuloma formation. The greater activity of the FcgammaRIIIB-NA1 genotype may also explain the greater severity of disease and its flare-ups in patients with this allele.