The latest consensus!

*Only for medical professionals to read and refer to 5 interpretations of the "Expert Consensus on the Clinical Application of AILD-related Autoantibody Testing" In the 2021 Annual Meeting of Rheumatology and Immunology Physicians of the Chinese Medical Doctor Association, Professor Zhou Renfang, Department of Laboratory Medicine, Wenling Hospital Affiliated to Wenzhou Medical University, for us Explain the relevant content of the "Expert Consensus on Clinical Application of Autoimmune Liver Disease (AILD)-related Autoantibody Detection"
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This article organizes the wonderful content of this speech and shares the academic feast with everyone! 1.
Background of consensus formation ● AILDAILD is a group of hepatobiliary inflammatory diseases mediated by abnormal autoimmunity.
According to different autoimmune attack targets, immune response types and clinical manifestations, it is mainly divided into the following categories: Autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and overlapping syndromes where the main features of any of the above two diseases appear at the same time
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The key to diagnosis and treatment of AILD is early diagnosis and early treatment to improve the prognosis and quality of life of patients, so as to delay the progression of liver cirrhosis and liver failure
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● Autoantibodies As an important laboratory indicator for AILD diagnosis and management, autoantibodies include AIH-related autoantibodies, PBC-related autoantibodies, and PSC-related autoantibodies.
They are mainly used for disease diagnosis and classification, prognosis prediction, disease monitoring, and pathogenesis and so on
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At present, AILD-related autoantibodies have become one of the routine autoantibody testing items in clinical laboratories
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However, because AILD-related autoantibodies involve a large number of antibodies, and various autoantibody detection methods are different, it is difficult to standardize and standardize the clinical application of their detection
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The "Expert Consensus on the Clinical Application of AILD-related Autoantibody Testing" (hereinafter referred to as the consensus), jointly completed by the Autoantibody Detection Professional Committee of the Rheumatology and Immunology Physician Branch of the Chinese Medical Doctor Association (hereinafter referred to as the consensus), was officially released in July 2020, aimed at improving China's clinical medical services.
The level of awareness of the workers on the scope of clinical testing of AILD-related autoantibodies, clinical significance, etc.
, provides a standardized and reliable AILD-related autoantibody testing result report for the clinic
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2.
The consensus consists of 5 parts.
The consensus is mainly divided into the following 5 aspects: ● 1.
AILD-related autoantibodies include AIH-related autoantibodies, PBC-related autoantibodies and PSC-related autoantibodies (see Figure 1)
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Figure 1.
Classification of AILD-related autoantibodies ● 2.
Clinical application of AILD-related autoantibody detection (1) AILD-related autoantibodies are mainly used for the diagnosis and classification of diseases, and are also helpful for the diagnosis of overlap syndrome
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For patients with abnormal liver function and unexplained hepatobiliary disease, it is recommended to detect AILD-related autoantibodies (see Figure 2)
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Figure 2.
AILD-related autoantibodies can be used for disease diagnosis and classification.
According to the diagnostic criteria of AIH, the detection of ANA, ASMA, anti-LKM-1 antibodies and anti-SLA/LP antibodies can be performed
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According to the results of autoantibody test, AIH is mainly divided into: AIH-1 which is mainly positive for ANA and ASMA, which is common in adults; AIH-1 which is mainly anti-LKM-1 antibody and anti-LC-1 antibody, which is more common in children.
Type 2
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According to the diagnostic criteria of PBC, an AMA test is required, of which the AMA-M2 subtype is the most valuable for the diagnosis of PBC
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Therefore, clinically for patients with unexplained cholestasis (usually elevated alkaline phosphatase and glutamyl transpeptidase), it is recommended to routinely test AMA, AMA-M2 subtypes and PBC-specific ANA
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PSC is an unexplained cholestatic liver disease characterized by intrahepatic and extrahepatic bile duct inflammation and fibrosis leading to multifocal stenosis.
However, autoantibodies have no diagnostic specificity for PSC, and their diagnostic value is limited
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Autoantibodies can be detected before the typical clinical symptoms of AILD patients appear.
Autoantibodies have predictive value for the disease, opening a new era of antibody detection
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It is recommended that those with positive AILD-related autoantibodies and normal liver biochemical indicators should be followed up regularly (see Figure 3)
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In addition, the detection of AMA and other antibodies in the relatives of PBC patients is conducive to the early detection of the disease
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Figure 3.
AILD-related autoantibodies can be used for disease prediction (3) Professor Zhou Renfang also introduced the detection methods of AILD-related autoantibodies, including related content of indirect immunofluorescence and other immunological methods (see Figure 4)
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Figure 4.
Detection of AILD-related autoantibodies (4) Clinical significance of AILD-related autoantibodies Next, Professor Zhou Renfang introduced in detail the clinical significance of AIH, PBC and PSC-related autoantibodies (see Figures 5, 6, 7)
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ANA: As a common autoantibody in autoimmune diseases, it is mainly found in patients with systemic autoimmune diseases, but also in organ-specific autoimmune diseases, and even in chronic infections, tumors and healthy people
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The positive rates in AIH, PBC, and PSC were 50%~75%, 50%, 8%~77%, respectively
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ASMA: Mainly exists in AIH, the positive rate in AIH-1 type is about 50%, and it can be positive alone in AIH patients.
ASMA can also be seen in patients with other liver diseases
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Anti-LKM-1 antibody: As a serum marker of AIH-2 type, it is mainly seen in children and adolescents with AIH
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It can also be seen in patients with chronic hepatitis C virus infection
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Anti-SLA/LP antibody: Anti-SLA/LP antibody is more common in middle-aged and elderly female AIH patients, and this autoantibody is rare in adolescents
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It is mainly seen in patients with AIH or AIH/PBC overlap syndrome, with a specificity of 98.
9% to 100% in the diagnosis of AIH.
AIH patients with positive autoantibodies have the characteristics of severe disease and recurrence
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Figure 5.
The clinical significance of AIH-related autoantibodies Figure 6.
The clinical significance of PBC-related autoantibodies Figure 7.
The clinical significance of PSC-related autoantibodies (5) Clinical interpretation of AILD-related autoantibody test results AILD-related autoantibody positive: not only seen in AILD patients can also appear in the preclinical stage of asymptomatic AILD, as well as viral hepatitis, drug-induced liver injury, alcoholic liver disease, etc.
, and attention should be paid to distinguish them
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Autoantibody negative AILD: may be due to low titers of autoantibodies, autoantibodies reagents, methods differences
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AILD-related autoantibody follow-up detection: The titer of children's AILD-related autoantibody may be related to disease activity and efficacy monitoring
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In the end, Professor Zhou Renfang concluded that the consensus mainly discusses and interprets the clinical application of autoimmune liver disease-related autoantibody detection from these five aspects
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Figure 8.
Conference summary