Implementation of the ANA HEp-2 consensus guidelines in Brazilian clinical laboratories

ABSTRACT Introduction: The detection of autoantibodies in HEp-2 cells represents a relevant tool for the diagnosis of autoimmune diseases, especially rheumatic autoimmune diseases. As a result of the methodological advances, the technique gradually increased the sensitivity, as well as the need for standardization. Objective: To evaluate the implementation of the Brazilian Consensus recommendations for autoantibody determination in HEp-2 cells. Methods: A structured form in a virtual platform was filled in by experts in clinical laboratories that carry out the methodology across the country. The questionnaire addressed the adoption of the Brazilian Consensus guidelines, detailing the technical aspects, quality control, the strategy for reading slides and the release of reports. Results: The study included 53 laboratories responsible for more than 300,000 antinuclear antibody (ANA) tests/month; more than half (58.5%) reported fully adopting the recommendations of the Brazilian Consensus. The majority (83.1%) used the 1:80 for screening dilution, and 75.5% of laboratories, perform education and quality control programs. Only 39.6% reported using more than one kit brand to perform the test, and 32.1% did not report observing all phases of the cell cycle during slide reading. The study also detected some heterogeneity among participants in the identification of patterns. Conclusion: The results confirm the adoption of the Brazilian Consensus recommendations by most of participating laboratories, although with variable extent. There is need for improvement in some aspects, especially those related to the quality control.

摘要
引言：自身抗体在HEp-2细胞（HEp-2 cells）中的检测是自身免疫性疾病，尤其是风湿性自身免疫疾病诊断的重要手段。随着检测方法学的进展，该技术的灵敏度逐步提升，同时对标准化工作的要求也日益增高。
目的：评估巴西共识中HEp-2细胞自身抗体检测相关建议的落实情况。
方法：由全国范围内开展该检测技术的临床实验室专家，通过虚拟平台填写结构化问卷。问卷围绕巴西共识指南的落实情况展开，涵盖技术要点、质量控制、玻片阅片策略及报告发布等核心内容。
结果：本研究共纳入53家实验室，这些实验室每月开展抗核抗体（antinuclear antibody, ANA）检测超30万次；超过半数（58.5%）的实验室表示已完全落实巴西共识的相关建议。绝大多数（83.1%）实验室采用1:80的筛查稀释比例，75.5%的实验室开展了教育培训与质量控制项目。仅39.6%的实验室报告使用了多种检测试剂盒品牌，32.1%的实验室未提及在玻片阅片过程中观察细胞周期的所有阶段。本研究还发现，参与者在抗原模式识别方面存在一定异质性。
结论：研究结果证实，多数参与实验室已落实巴西共识的相关建议，但落实程度存在差异。部分环节仍有待优化，尤其是与质量控制相关的内容。