Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, 145 Middle Shandong Road, Shanghai 200001, China.
Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, 145 Middle Shandong Road, Shanghai 200001, China.
J Autoimmun. 2019 May;99:33-38. doi: 10.1016/j.jaut.2019.01.005. Epub 2019 Jan 30.
The most highly directed and specific autoantibody in human immunopathology is the serologic hallmark of primary biliary cholangitis (PBC), antimitochondrial antibodies (AMAs). However the clinical significance of finding a positive AMA, with normal alkaline phosphatase (ALP) remains enigmatic.
We took advantage of 169 consecutive outpatients who were identified as having a positive AMA, but normal ALP levels between January 2012 and January 2018. A liver biopsy was performed on 67/169 of these AMA positive normal ALP patients.
In all 169 patients we reconfirmed the AMA and also performed anti-gp210 and anti-sp100, liver stiffness (LSM) assessed by vibration-controlled transient elastography (VCTE), an abdominal computed tomography (CT) scan, and either a magnetic resonance imaging (MRI) or ultrasound. The liver biopsies were reviewed by two unbiased observers. 87.6% of the 169 patients were females with a mean age of 46; the median AMA titer 1:320; an elevated serum IgM was found in 53.3%. Importantly, in patients with a liver biopsy, 55（82.1%）out of 67 had varying degrees of cholangitis activity, diagnostic of PBC.
In patients who were AMA-positive but had normal ALP levels, more than 80% were associated with histological classic PBC. These data emphasize the importance of a positive AMA, even with a normal ALP and also question the role of ALP as a sole surrogate marker of cholangitis.
在人类免疫病理学中，最具针对性和特异性的自身抗体是原发性胆汁性胆管炎（PBC）的血清学标志——抗线粒体抗体（AMA）。然而，发现阳性 AMA 而碱性磷酸酶（ALP）正常的临床意义仍然是一个谜。
我们利用了 2012 年 1 月至 2018 年 1 月期间连续 169 例被诊断为 AMA 阳性但 ALP 水平正常的门诊患者。对其中 67/169 例 AMA 阳性、ALP 正常的患者进行了肝活检。
在所有 169 例患者中，我们均再次确认了 AMA，同时还进行了抗 gp210 和抗 sp100 检测、通过振动控制瞬时弹性成像（VCTE）评估肝硬度（LSM）、进行腹部计算机断层扫描（CT），以及磁共振成像（MRI）或超声检查。肝脏活检由两位无偏见的观察者进行了评估。169 例患者中 87.6%为女性，平均年龄为 46 岁；AMA 滴度中位数为 1:320；53.3%的患者血清 IgM 升高。重要的是，在进行肝活检的 67 例患者中，55 例（82.1%）存在不同程度的胆管炎活动，符合 PBC 的诊断。
在 AMA 阳性但 ALP 水平正常的患者中，超过 80%的患者与组织学经典 PBC 相关。这些数据强调了 AMA 阳性的重要性，即使 ALP 正常，也质疑了 ALP 作为胆管炎唯一替代标志物的作用。
