Mejdoub Sabrina, Hamza Zouhour, Hachicha Hend, Chtourou Lassaad, Marrzouk Sameh, Feki Sawsan, Jerbi Ameni, Boukthir Semia, Bahloul Zouhir, Tahri Nabil, Masmoudi Hatem
Immunology Department, Habib Bourguiba Hospital, University of Sfax, Tunisia
Gastro-enterology Department, Hedi Chaker Hospital, University of Sfax, Tunisia
Ann Biol Clin (Paris). 2022 Sep 1;80(5):423-429. doi: 10.1684/abc.2022.1761.
Anti-mitochondrial antibodies (AMA) represent serological markers of primary biliary cholangitis (PBC). Investigation of these autoantibodies can be performed by indirect immunofluorescence (IIF) on tissue sections or immunodot using M2 and M2-3E antigens. We aimed to evaluate the concordance of these immunological tests and their performance in PBC diagnosis. We reviewed sera which were tested for autoimmune liver disease anti-bodies by IIF (EUROIMMUN®) and immunodot (EUROIMMUN®). Results of IIF (AMA) and immunodot (anti-M2 and anti-M2-3E) were analyzed. A focus was given on positive results for AMA and/or anti-M2 and/or anti-M2-3E. According to available clinical data, patients were divided into two groups "PBC" and "Non PBC". Three-hundred-nineteen sera were tested by both techniques. Results of AMA, anti-M2 and anti-M2-3E were concordant in 296 cases (92.8%). Indeed, the three biomarkers were negative in 237 cases (74.3%) and positive in 59 cases (18.5%). Eighty-two sera were tested positive for AMA and/or anti-M2 and/or anti-M2-3E. Clinical data were available for 30 patients. In "PBC" group (n = 15), AMA, anti-M2 and anti-M2-3E antibodies were positive in 14/15 cases. PBC diagnosis was made in 12/15 patients without requiring liver biopsy. In "non PBC" group (n = 15), AMA, anti-M2 and antiM2-3E antibodies were positive in 9/15 cases. However, PBC diagnosis was not reached in the absence of other diagnostic criteria. IIF represents a first-line technique for AMA detection while immunodot is useful to confirm antigenic specificity in IIF-AMA positive cases. Anti-M2 and/or anti-M2-3E can be detected in some IIF-AMA negative cases. Interpretation of these tests'results relays mainly on clinical context.
抗线粒体抗体（AMA）是原发性胆汁性胆管炎（PBC）的血清学标志物。这些自身抗体的检测可通过组织切片间接免疫荧光法（IIF）或使用M2和M2-3E抗原的免疫斑点法进行。我们旨在评估这些免疫学检测方法的一致性及其在PBC诊断中的性能。我们回顾了通过IIF（EUROIMMUN®）和免疫斑点法（EUROIMMUN®）检测自身免疫性肝病抗体的血清。分析了IIF（AMA）和免疫斑点法（抗M2和抗M2-3E）的结果。重点关注AMA和/或抗M2和/或抗M2-3E的阳性结果。根据现有临床数据，将患者分为“PBC”和“非PBC”两组。两种技术共检测了319份血清。AMA、抗M2和抗M2-3E的结果在296例（92.8%）中一致。实际上，这三种生物标志物在237例（74.3%）中为阴性，在59例（18.5%）中为阳性。82份血清检测AMA和/或抗M2和/或抗M2-3E呈阳性。有30例患者的临床数据可用。在“PBC”组（n = 15）中，14/15例AMA、抗M2和抗M2-3E抗体呈阳性。12/15例患者在无需肝活检的情况下确诊为PBC。在“非PBC”组（n = 15）中，9/15例AMA、抗M2和抗M2-3E抗体呈阳性。然而，在缺乏其他诊断标准的情况下未确诊为PBC。IIF是检测AMA的一线技术，而免疫斑点法有助于在IIF-AMA阳性病例中确认抗原特异性。在一些IIF-AMA阴性病例中可检测到抗M2和/或抗M2-3E。这些检测结果的解读主要依赖于临床背景。
