ABSTRACT
Abstract Background: The VI Brazilian Consensus on Autoantibodies against HEp-2 cells for determination of autoantibodies against cellular constituents on HEp-2 cells was held on September, 2019, in Fortaleza (CE, Brazil). The guidelines in this edition were formulated by the group of Brazilian experts discussing the classification of complex patterns, the classification of the nuclear discrete dots (few and multiple), the identification of the discrete fine speckled pattern (AC-4a) and improvements on the ANA report. Mainbody: Sixteen Brazilian researchers and experts from universities and clinical laboratories representing the various geographical regions of Brazil participated in the meeting. Four main topics were discussed: (1) How to classify patterns with fluorescence in more than one cell compartment considering three relevant categoris: composite patterns, mixed patterns and multiple patterns; (2) The splitting of the discrete nuclear dots pattern into the multiple discrete nuclear dots (AC-6) and few discrete nuclear dots (AC-7) patterns, respectively; (3) Inclusion of a novel nuclear pattern characterized by discrete fine speckled pattern highly associated with antibodies to SS-A/Ro60, classified as AC-4a. In addition, adjustments on the Brazilian Consensus nomenclature were implemented aiming to harmonize the designation of some patterns with the International Consensus on ANA Patterns (ICAP). Furthermore, the designations of the PCNA-like pattern (AC-13), CENP-F-like pattern (AC-14) and Topo I-like pattern (AC-29) were adjusted in accordance to ICAP. Finally, there was a recommendation for adjustment in the test report in order to address the status of nuclear envelope staining. For all topics, the aim was to establish specific guidelines for laboratories and clinicians. All recommendations were based on consensus among participants. All recommendations from the V Consensus were maintained and there was relevant progress in the BCA/HEp-2 guidelines and further harmonization with ICAP. Conclusion: The VI BCA/HEp-2 edition was successful in establishing important recommendations regarding the classification of complex patterns, in supporting the identification of a novel pattern within the AC-4 group and in the harmonization process with the ICAP terminology.
ABSTRACT
Objetivo: O IV Consenso Brasileiro para Pesquisa de Autoanticorpos em Células HEp-2 (FAN) realizado em Vitória (ES), no dia 18 de setembro de 2012, objetivou discutir estratégias e recomendações relacionadas ao procedimento técnico, à padronização e à interpretação dos resultados da pesquisa de autoanticorpos em células HEp-2. Métodos: Participaram do evento 23 pesquisadores e especialistas de Universidades e laboratórios brasileiros. Foram abordados diferentes tópicos, discutidos amplamente a fim de se estabelecer recomendações específicas. Resultados e conclusão: O IV Consenso integrou à árvore de decisão o padrão citoplasmático em Anéis e Bastões, o padrão nuclear pontilhado Quasi-homogêneo (QH) e o padrão misto CENP-F. Discutiu-se ainda a necessidade de atenção para a classificação do padrão misto relacionado à presença de anticorpos anti-DNA topoisomerase I (Scl70), compreendendo os componentes nuclear pontilhado fino, nucleolar homogêneo, NOR na placa metafásica e citoplasmático pontilhado fino. Foram sugeridas diretrizes para o controle de qualidade do teste, diluição de triagem e diluição de esgotamento, e foi emitido alerta quanto à necessidade de atenção em relação à heterogeneidade de substratos disponíveis no mercado e a utilização de metodologias automatizadas para detecção de autoanticorpos. .
Objective: The Fourth Brazilian Consensus for Autoantibodies Screening in HEp-2 Cells (ANA) was held in Vitória, Espírito Santo, and aimed to discuss strategies and recommendations about the technique, standardization, interpretation and quality control of the indirect immunofluorescence reaction on HEp-2 cells. Methods: Twenty three ANA experts from university centers and private laboratories in different areas from Brazil discussed and agreed upon recommendations for the fourth edition of the Brazilian Consensus for Autoantibodies Screening in HEp-2 Cells. Results and conclusion: The 4th ANA Consensus included three novel patterns into the existing algorithm (cytoplasmic Rods and Rings, nuclear Quasi-homogeneous, and CENP-F). Emphasis was given to the need of attention in describing the peculiar mixed pattern elicited by anti-DNA topoisomerase I (Scl-70) autoantibodies, comprising nuclear fine specked, nucleolar homogeneous pattern, NOR staining in metaphase plates, and cytoplasmic fine speckled patterns. The group also emphasized the need for continuous quality control in indirect immunofluorescence assays, the establishment of screening dilutions, as well as conjugate titration. An alert was made regarding the heterogeneity of commercial kits in defining patterns and the use of solid phase methodologies to determine the presence of autoantibodies. .