Division of Inflammation and Infection/Clinical Immunology and Transfusion Medicine, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
Division of Inflammation and Infection/Rheumatology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
Clin Exp Immunol. 2021 Jan;203(1):22-31. doi: 10.1111/cei.13512. Epub 2020 Sep 29.
Knowledge of concomitant autoimmune liver diseases (AILD) is more detailed in primary Sjögren's syndrome (pSS) compared to systemic lupus erythematosus (SLE). Herein, the prevalence of autoantibodies associated with autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) was investigated in stored sera from patients with SLE (n = 280) and pSS (n = 114). Antibodies against mitochondria (AMA), liver-kidney microsomal (LKM) antigen, smooth muscle (SMA) and anti-nuclear antibodies (ANA) were analysed with immunofluorescence microscopy. In addition, AILD-associated autoantibodies were tested with immunoblot. Prior to sampling, eight SLE (2·9%) and three pSS (2·6%) cases were diagnosed with AILD. Among SLE-cases without known AILD (n = 272), 26 (9·6%) had PBC-associated autoantibodies, 15 (5·5%) AIH-associated autoantibodies (excluding ANA) and one serological overlap. Most subjects with PBC-associated autoantibodies had liver enzymes within reference limits (22 of 27, 81%) or mild laboratory cholestasis (two of 27, 7·4%), while one fulfilled the diagnostic PBC-criteria. AMA-M2 detected by immunoblot was the most common PBC-associated autoantibody in SLE (20 of 272, 7·4%). The prevalence of SMA (4·4%) was comparable with a healthy reference population, but associated with elevated liver enzymes in four of 12 (25%), none meeting AIH-criteria. The patient with combined AIH/PBC-serology had liver enzymes within reference limits. Among pSS cases without known AILD (n = 111), nine (8·1%) had PBC-associated, 12 (10·8%) AIH-associated autoantibodies and two overlapped. PBC-associated autoantibodies were found as frequently in SLE as in pSS but were, with few exceptions, not associated with laboratory signs of liver disease. Overall, AILD-associated autoantibodies were predominantly detected by immunoblot and no significant difference in liver enzymes was found between AILD autoantibody-negative and -positive patients.
原发性干燥综合征 (pSS) 对伴随自身免疫性肝病 (AILD) 的了解比系统性红斑狼疮 (SLE) 更详细。本研究旨在调查 SLE（n=280）和 pSS（n=114）患者储存血清中与自身免疫性肝炎 (AIH) 和原发性胆汁性胆管炎 (PBC) 相关的自身抗体的患病率。使用免疫荧光显微镜分析抗线粒体 (AMA)、肝-肾微粒体 (LKM) 抗原、平滑肌 (SMA) 和抗核抗体 (ANA)。此外，还使用免疫印迹法检测了 AILD 相关的自身抗体。在取样前，8 例 SLE（2.9%）和 3 例 pSS（2.6%）被诊断为 AILD。在无已知 AILD 的 SLE 病例中（n=272），26 例（9.6%）存在 PBC 相关自身抗体，15 例（5.5%）存在 AIH 相关自身抗体（不包括 ANA）和 1 例存在重叠。大多数 PBC 相关自身抗体阳性的 SLE 患者的肝酶处于参考范围内（27 例中的 22 例，81%）或存在轻度实验室胆汁淤积（27 例中的 2 例，7.4%），而仅有 1 例符合 PBC 诊断标准。免疫印迹法检测到的 AMA-M2 是 SLE 中最常见的 PBC 相关自身抗体（272 例中的 20 例，7.4%）。SMA（4.4%）的患病率与健康参考人群相当，但在 12 例中的 4 例（25%）中与肝酶升高相关，均不符合 AIH 标准。合并 AIH/PBC 血清学的患者肝酶处于参考范围内。在无已知 AILD 的 pSS 病例中（n=111），9 例（8.1%）存在 PBC 相关自身抗体，12 例（10.8%）存在 AIH 相关自身抗体，2 例存在重叠。SLE 和 pSS 中均发现 PBC 相关自身抗体，但除少数例外，这些自身抗体均与肝脏疾病的实验室迹象无关。总体而言，AILD 相关自身抗体主要通过免疫印迹法检测，AILD 自身抗体阴性和阳性患者的肝酶无显著差异。
