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1.
Clin Chem Lab Med ; 61(7): 1167-1198, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-36989417

RESUMEN

OBJECTIVES: Antinuclear antibodies (ANA) are important for the diagnosis of various autoimmune diseases. ANA are usually detected by indirect immunofluorescence assay (IFA) using HEp-2 cells (HEp-2 IFA). There are many variables influencing HEp-2 IFA results, such as subjective visual reading, serum screening dilution, substrate manufacturing, microscope components and conjugate. Newer developments on ANA testing that offer novel features adopted by some clinical laboratories include automated computer-assisted diagnosis (CAD) systems and solid phase assays (SPA). METHODS: A group of experts reviewed current literature and established recommendations on methodological aspects of ANA testing. This process was supported by a two round Delphi exercise. International expert groups that participated in this initiative included (i) the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group "Autoimmunity Testing"; (ii) the European Autoimmune Standardization Initiative (EASI); and (iii) the International Consensus on ANA Patterns (ICAP). RESULTS: In total, 35 recommendations/statements related to (i) ANA testing and reporting by HEp-2 IFA; (ii) HEp-2 IFA methodological aspects including substrate/conjugate selection and the application of CAD systems; (iii) quality assurance; (iv) HEp-2 IFA validation/verification approaches and (v) SPA were formulated. Globally, 95% of all submitted scores in the final Delphi round were above 6 (moderately agree, agree or strongly agree) and 85% above 7 (agree and strongly agree), indicating strong international support for the proposed recommendations. CONCLUSIONS: These recommendations are an important step to achieve high quality ANA testing.


Asunto(s)
Anticuerpos Antinucleares , Enfermedades Autoinmunes , Humanos , Enfermedades Autoinmunes/diagnóstico , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Estándares de Referencia , Línea Celular Tumoral
2.
Respir Med ; 182: 106405, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33894442

RESUMEN

INTRODUCTION/OBJECTIVES: To define the performance of Minor Salivary Gland Biopsy (MSGB) and Dry Eye Tests (DET) to detect occult Sjögren Syndrome (SS) among Interstitial Pneumonia with Autoimmune Features (IPAF) patients. METHODS: Prospective study. Interstitial Lung Disease (ILD) patients without defined Connective Tissue Disease and one or more IPAF classification domains or xerophthalmia were included. MSGB, Schirmer's test (ST) and Ocular Staining Score (OSS) were performed in a blinded manner by experienced specialists. MSGB with ≥1 focus of lymphocytes and Dry Eye Test (DET) with OSS ≥ 5 and/or ST < 5 s were considered positive. SS was diagnosed according to the ACR 2016 criteria. RESULTS: 534 patients on the first consult were screened. 67 patients had at least one IPAF criteria, 53 (79.1%) female, mean age (SD) 64.2 years old (10.8). Positive ST in 36 (53.7%), positive OSS in 29 (43.3%) and positive MSGB in 36 (53.7%) were found. Finally, 27 (40.3%) met SS diagnostic criteria. 25 (37.3%) and 18 (26.8%) of them did not report dry eyes or dry mouth, respectively. 53 (79.1%) had negative anti SSA/Ro, 57 (85.1%) had negative anti LA/SSB, 30 (44.7%) had negative ANA, and 52 (77.6%) had negative RF, respectively. A significantly higher proportion of ANA (+), anti-SSA/Ro (+), anti-SSB/La (+), positive DET and positive MSGB were found in the SS population. CONCLUSIONS: A significant proportion of patients with occult SS were found in our study. MSGB and DET may be considered in the evaluation of IPAF patients.


Asunto(s)
Enfermedades Pulmonares Intersticiales/etiología , Síndrome de Sjögren/diagnóstico , Anciano , Autoinmunidad , Biopsia , Técnicas de Diagnóstico Oftalmológico , Síndromes de Ojo Seco/diagnóstico , Femenino , Humanos , Enfermedades Pulmonares Intersticiales/inmunología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Glándulas Salivales/patología , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/patología
3.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;55(2): 151-163, abr. 2021. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1355557

RESUMEN

Resumen La determinación de anticuerpos anti-citoplasma de neutrófilos (ANCA) es utilizada en la clínica diaria como una herramienta diagnóstica en distintas formas de vasculitis de pequeños vasos (vasculitis asociadas a ANCA), incluyendo la granulomatosis con poliangeítis (antes: granulomatosis de Wegener), poliangeítis microscópica y granulomatosis eosinofílica con poliangeítis (antes: síndrome de Churg-Strauss), y como apoyo diagnóstico de colitis ulcerosa, colangitis esclerosante primaria y enfermedad de Crohn. Estos anticuerpos están dirigidos contra distintos epítopos antigénicos de diferentes proteínas presentes en el citoplasma del neutrófilo. La determinación de ANCA, habitualmente realizada por la técnica de inmunofluorescencia indirecta (IFI), presenta cierto grado de complejidad en la definición de las imágenes de los diferentes patrones, variabilidad en la forma de trabajo y expresión de resultados. El 24 de octubre de 2018 en el marco del X Congreso Argentino de la Calidad en el Laboratorio Clínico y VIII Jornadas Latinoamericanas de la Calidad en el Laboratorio Clínico, en la Ciudad de Buenos Aires, se realizó una reunión de Armonización de la Determinación de ANCA por IFI con el objeto de presentar, discutir y consensuar los distintos aspectos que se presentan en esta técnica. Las propuestas iniciales fueron discutidas arribándose a recomendaciones generales para proporcionar estándares de trabajo e interpretación de imágenes con el objeto de disminuir la variabilidad de resultados entre los laboratorios clínico-inmunológicos.


Abstract Anti-neutrophil cytoplasmic antibodies (ANCA) tests are widely used in daily clinical practice as a useful tool for the diagnosis of pathologies such as granulomatosis with polyangiitis, microscopic polyangiitis, pauci-immune necrotizing segmental glomerulonephritis and eosinophilic granulomatosis with polyangiitis, ulcerative colitis, primary sclerosing cholangitis, Crohn's disease, etc. These antibodies are directed against different antigenic epitopes of various proteins which are present in the neutrophil cytoplasm. ANCA testing is usually carried out by using indirect immunofluorescence (IIF) method. The determination of ANCA presents some difficulties in the definition of the images of the different patterns, work protocols and result reports uniformity. The "Harmonization Conference on the Determination of ANCA by IIF" was held within the framework of the X Argentine Congress on Quality in the Clinical Laboratory and VIII Latin American Conference on Quality in the Clinical Laboratory, in Buenos Aires, Argentina, on October 24, 2018, in order to present, discuss and agree on different aspects of this method. Some initial proposals were discussed, arriving at general recommendations to provide standards of work and an image interpretation, with the aim of reducing the variability of results among the clinical-immunological laboratories.


Resumo A determinação de anticorpos anti-citoplasma de neutrófilos (ANCA) é utilizada na prática clínica diária como um suporte diagnóstico para várias patologias, como granulomatose com poliangiite, poliangiite microscópica, glomerulonefrite segmentar necrotizante pauci-imune e granulomatose eosinofílica com poliangiite, poliarterite nodosa, colite ulcerosa, colangite esclerosante primária, doença de Crohn. Esses anticorpos são dirigidos contra diferentes epítopos antigênicos de diferentes proteínas presentes no citoplasma do neutrófilo. A determinação de ANCA, normalmente realizada pela técnica de imunofluorescência indireta IFI, apresenta certo grau de complexidade na definição das imagens dos diferentes padrões, variabilidade na forma de trabalho e expressão de resultados. Em 24 de outubro de 2018, no âmbito do X Congreso Argentino de la Calidad en el Laboratorio Clínico (X Congresso Argentino da Qualidade no Laboratório Clínico) e VIII Jornadas Latinoamericanas de la Calidad en el Laboratorio Clínico (VIII Jornadas Latino-americanas da Qualidade no Laboratório), na cidade de Buenos Aires, foi realizada uma Jornada de Harmonização da Determinação de ANCA pelo IFI a fim de apresentar, discutir e concordar sobre os diferentes aspectos que são apresentados nesta técnica. As propostas iniciais foram discutidas, chegando a recomendações gerais para fornecer padrões de trabalho e interpretação de imagens visando reduzir a variabilidade de resultados entre os laboratórios clínico-imunológicos.

4.
Adv Rheumatol ; 61: 52, 2021. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1339073

RESUMEN

Abstract Background: Clinically evident interstitial lung disease (ILD) affects between 10 and 42% of the patients with rheumatoid arthritis (RA). Airway involvement seems to be even more common. Most of the available evidence comes from studies performed in established RA patients. The aim of our study was to know the prevalence of non-diagnosed lung disease (airway and interstitial involvement) in patients with early RA and look for associated factors. Methods: We designed an observational, multicenter, cross-sectional study, and included patients with RA of less than two years since diagnosis. We performed a structured questionnaire, HRCT and lung functional tests looking for lung disease, together with joint disease evaluation. We analyzed which variables were associated with the presence of lung disease on HRCT. Results: We included 83 patients, 83% females. The median (IQR) of time since RA diagnosis was 3 (1-6) months. In the HRCT, 57 patients had airway compromisea (72%), and 6 had interstitial abnormalities (7.5%). The most common altertion found in lung functional tests was a reduced DLCO (14%). The presence of at least one abnormality in the physical exam was associated with lung involvement on HRCT [13 (21.6%) vs 0 (0%); p = 0.026]. Also, patients with lung involvement presented significantly lower values of FVC% and DLCO%, and higher values of RV/TLC. No variable related to joint involvement was found associated with alterations in HRCT. Conclusion: Our study shows that a large proportion of early RA patients has abnormal findings in HRCT. Further studies are required to confirm these findings.

5.
Prague Med Rep ; 121(3): 194-199, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33030148

RESUMEN

Cryoglobulins are immunoglobulins that undergo reversible precipitation at cold temperatures. Monoclonal type-I cryoglobulinaemia is the least frequent and is associated to hematological diseases such as multiple myeloma, Waldenström's macroglobulinaemia, chronic lymphocytic leukaemia and lymphoma. We describe the case of a 60-year-old female patient, who suffered from burning pain in her feet for ten months before her admission. The patient presented intermittent distal cyanosis that progressed to digital ischaemia. She also reported paresthesia in her hands, difficulty in writing, and a 26-kg-weight loss. At the physical examination, it was identified livedo reticularis, palpable purpura, and painful ecchymotic lesions in her calves and feet. Moreover, peripheral pulses were palpable and symmetrical. It was observed an atrophy of the right first dorsal interosseous and both extensor digitorum brevis, as well as a distal bilateral apalesthesia and allodynia. Both Achilles reflexes were absent. Laboratory tests revealed anemia, high erythrosedimentation rate and C-reactive protein. Serum protein electrophoresis showed a monoclonal IgG-Kappa gammopathy. The results also evidenced the presence of Bence-Jones proteinuria. The bone marrow biopsy revealed less than 10% of plasma cells, and skin biopsy informed leukocytoclastic vasculitis. The patient was treated with high-dose intravenous steroids and cyclophosphamide. The treatment showed that the skin lesions had improved, pain disappeared and motor deficit stopped its progression.


Asunto(s)
Crioglobulinemia , Vasculitis por IgA , Gammopatía Monoclonal de Relevancia Indeterminada , Mieloma Múltiple , Vasculitis Leucocitoclástica Cutánea , Adulto , Crioglobulinemia/complicaciones , Crioglobulinemia/diagnóstico , Femenino , Humanos , Persona de Mediana Edad
6.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;46(1): 3-13, mar. 2012. ilus, tab
Artículo en Español | LILACS | ID: lil-639595

RESUMEN

La presencia de anticuerpos antinucleares (AAN) es el denominador común de muchas enfermedades autoinmunes sistémicas y su significancia clínica depende de la metodología utilizada en su determinación. En la actualidad, la inmunofluorescencia indirecta (IFI) utilizando células HEp-2 como sustrato es la técnica más usada. Siendo un procedimiento subjetivo se deben optimizar los métodos de estandarización de las distintas variables involucradas, para asegurar la calidad de los resultados obtenidos. El uso de este sustrato permite la descripción no sólo de patrones de fluorescencia nucleares sino también citoplasmáticos y de diferentes organelas. El 29 de agosto de 2008 se llevó a cabo en Buenos Aires el Primer Consenso Argentino para la Estandarización de la Determinación de AAN por IFI-HEp-2, con la participación de 28 expertos. Se discutieron los aspectos metodológicos más importantes y se decidió llamar a la determinación "anticuerpos anti núcleo-citoplasmáticos". Se consensuó la sigla representativa de la determinación, el nombre en español de los diferentes patrones y el uso de controles de calidad internos y externos. La unificación de criterios llevará a la optimización de los resultados y a su correcta interpretación.


Antinuclear antibodies (ANA) are a common feature of many systemic autoimmune diseases. Their clinical significance depends on working conditions. Nowadays, indirect immunofluorescence (IFI), using HEp-2 cells as substrate, is the most used assay. Since IFI is a subjective method, different variables should be strictly standardized to assure the quality of the results. By using HEp-2 cells, not only a nuclear fluorescent pattern will be described but also cytoplasmic and different organelle patterns. In order to standardize the operative procedures, the 1st Argentine Consensus for AAN IFI HEp-2 determination took place in Buenos Aires on August 29, 2008, with 28 experts as participants. The most important methodological aspects were discussed and the assay was decided to be named: anti nuclear- cytoplasmic antibodies. Consesus was also CAICYThed about the acronym for the determination, the Spanish names for the different patterns and the use of internal and external quality controls. Using common criteria will improve the quality of the results and optimize assay interpretation.


A presenga de anticorpos antinucleares (AAN) é o denominador comum de muitas doengas autoimunes sistémicas e sua significancia clínica depende da metodologia utilizada em sua determinagáo. Na atualidade, a imunofluorescéncia indireta (IFI) utilizando células HEp-2 como substrato é a técnica mais utilizada. Sendo um procedimento subjetivo devem ser otimizados os métodos de padronizagáo das diferentes variáveis envolvidas, para garantir a qualidade dos resultados obtidos. O uso deste substrato permite a descrigáo náo apenas de padróes de fluorescéncia nucleares mas também citoplasmáticos e de diferentes organelas. Em 29 de agosto de 2008, foi levado a cabo, em Buenos Aires, o Primeiro Consenso Argentino para a Padronizagáo da Determinagáo de AAN por IFI-HEp-2, com a participagáo de 28 especialistas. Foram discutidos os aspectos metodológicos mais importantes e se decidiu chamar a determinagáo de "anticorpos antinúcleo-citoplasmáticos". Foi estabelecida por consenso a sigla representativa da determinagáo, o nome em espanhol dos diferentes padróes e o uso de controles de qualidade internos e externos. A unificagáo de critérios levará a otimizago dos resultados e a sua correta interpretagáo.


Asunto(s)
Anticuerpos Antinucleares/análisis , Anticuerpos Antinucleares/inmunología , Técnica del Anticuerpo Fluorescente Indirecta/normas , Argentina , Control de Calidad , Evaluación de Programas y Proyectos de Salud , Técnica del Anticuerpo Fluorescente Indirecta/métodos
7.
Rev. bras. reumatol ; Rev. bras. reumatol;43(3): 129-140, maio-jun. 2003. tab
Artículo en Portugués | LILACS | ID: lil-386643

RESUMEN

Objetivo: O Segundo Consenso Brasileiro de Fator Antinuclear (FAN) em Células HEp-2 ratificou os algoritmos de decisão para leitura dos padrões do FAN na imunofluorescência indireta vistos na primeira edição do Consenso Brasileiro, adicionando ainda um novo algoritmo relacionado com os padrões mistos. Métodos: Tendo em vista a habilidade do teste em detectar auto-antígenos nos distintos compartimentos celulares, e não apenas no núcleo, propõe-se novas denominações para este exame laboratorial. Resultados e Conclusões: Como novas denominações algumas sugestões foram igualmente aceitas, dentro do tema "pesquisa de aut-anticorpos contra constituintes do núcleo (FAN HEp-2), nucléolo, citoplasma e aparelho mitótico". Foram abordadas as principais relevâncias clínicas com os padrões de FAN descritos, facilitando o melhor uso do ensaio pelo médico


Asunto(s)
Autoanticuerpos , Autoantígenos , Técnica del Anticuerpo Fluorescente
8.
Rev. mex. reumatol ; 14(2): 43-50, mar.-abr. 1999. tab
Artículo en Español | LILACS | ID: lil-266823

RESUMEN

En el Taller de Trabajo de Anticuerpos Anti-Nucleares realizado en el marco del Primer Workshop y Conferencia Latinoamericana de Autoinmunidad (1997), se analizaron 27 sueros de pacientes con distintas enfermedades reumáticas sistémicas: lupus eritematosos sistémico (n=15), artritis reumatoide (n=4), síndrome de Sjögren (n=3), enfermedad mixta del tejido conjuntivo (n=1), síndrome indiferenciado del tejido conjuntivo (n=1), polimiositis/dermatomiositis (n=2) y escleroderma (n=1) y 3 sueros de individuos normales para el estudio de ANA por inmunofluorescencia indirecta (IFI), y anticuerpos anti-Sm, anti-RNP, anti-SSA/Ro, anti-SSB/La, anti-Scl70 y anti-Jol utilizando las técnicas de Doble Difusión Radial (DDR), Enzimoinmuno Análisis (ELISA) y Western blot (WB) de origen comercial. En el estudio de ANAs por IFI se observaron 4 patrones: nuclear: moteado fino, metafase negativa (n=9); nuclear: moteado grueso, metafase negativa (n=4); nuclear: homogéneo, metafase positiva homogénea (n=10); nucleolar y nucleoplásmico, metafase positiva homogénea (n=1). En 6 sueros, incluyendo los 3 controles normales, los ANA por IFI dieron resultados negativos. Comparando los patrones observados por IFI con las especificidades obtenidas por las téncnicas de DDR, ELISA y WB, surge que los mismos fueron orientativos hacia la especificidad de los distinto anticuerpos presentes, no pudiendo descartar la presencia de ninguno de los otros anticuerpos estudiados. Por último, se compararon los resultados obtenidos por los métodos de DDR, ELISA y WB observándose que la proporción de resultados positivos para el Ac. anti-Sm por WB difiere significativamente (p<0.05) con respecto a la DDR y a uno de los equipos de ELISA utilizados


Asunto(s)
Anticuerpos Antinucleares , Enfermedades Reumáticas/diagnóstico , Microscopía Fluorescente , Ensayo de Inmunoadsorción Enzimática , Western Blotting
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