台灣多中心研究：系統性紅斑狼瘡患者與非患者的抗核抗體型態分布

Distribution of Antinuclear Antibody Patterns in Patients With and Without Systemic Lupus Erythematosus: A Multi-Center Study from Taiwan

研究目的
國際抗核抗體型態共識（ICAP）提供了29種ANA型態的標準化分類，有助於更精準解讀間接免疫螢光（IIF）檢測結果。雖然ANA檢測廣泛應用於系統性紅斑狼瘡（SLE）診斷，台灣族群中根據ICAP定義的ANA型態分布卻尚未被充分描述。本研究旨在分析ANA陽性的SLE患者之ANA型態分布，並比較SLE與非SLE個體之ANA型態頻率。
研究方法
本回溯性研究納入2019年1月至2021年9月期間，在長庚紀念醫院接受ANA檢測（IIF HEp-2系統）之38,572名個體。ANA型態依ICAP系統進行分類。主要分析僅納入具有單一ANA型態者，排除具有混合型或分類不一致型態之個體。次要分析比較所有被診斷為SLE的患者（包括ANA陰性者）與非SLE個體。
研究結果
在4,603名ANA陽性個體中，共383名被診斷為SLE。最常見的ANA型態為AC-5（34.5%），其次為AC-1（20.9%）和AC-4（15.1%）。在廣泛比較中，AC-1至AC-5型態及核仁型態（AC-8/9/10）在SLE患者中顯著多見於非SLE個體。
結論
本研究為首度使用ICAP分類描述台灣SLE患者之ANA型態分布。研究結果揭示區域性ANA型態特色，並支持ANA型態標準化解讀在自體免疫疾病評估中的臨床價值。

Objectives: The International Consensus on Antinuclear Antibody Patterns (ICAP) provides a standardized classification of 29 ANA patterns, facilitating more precise interpretation of indirect immunofluorescence (IIF) results. Although ANA testing is widely used in the diagnosis of systemic lupus erythematosus (SLE), the distribution of ICAP-defined ANA patterns in Taiwanese populations remains poorly characterized. This study aims to analyze the distribution of ANA patterns among ANA-positive SLE patients and to compare ANA pattern frequencies between SLE and non-SLE individuals.
Methods: This retrospective study included 38,572 individuals who underwent ANA testing using the IIF HEp-2 assay at Chang Gung Memorial Hospital from January 2019 to September 2021. ANA patterns were classified according to the ICAP system. In the primary analysis, only individuals with a single ANA pattern were included; those with mixed or inconsistently classified patterns were excluded. A secondary analysis compared all patients diagnosed with SLE—including those who were ANA-negative—with non-SLE individuals.
Results: Among 4,603 ANA-positive individuals, 383 were diagnosed with SLE. The most common ANA pattern was AC-5 (34.5%), followed by AC-1 (20.9%) and AC-4 (15.1%). In the broader comparison, patterns AC-1 through AC-5 and nucleolar patterns (AC-8/9/10) were more frequently observed in SLE than in non-SLE individuals.
Conclusion: This is the first study to characterize ANA pattern distributions in Taiwanese SLE patients using ICAP classification. The findings provide insight into regional ANA pattern features and support the clinical relevance of standardized pattern interpretation in autoimmune disease evaluation.