Rodríguez Cruz Pedro M, Luo Yue-Bei, Miller James, Junckerstorff Reimar C, Mastaglia Frank L, Fabian Victoria
Centre for Neuromuscular and Neurological Disorders, Western Australian Neuroscience Research Institute, Perth, Australia; Department of Neurology, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
Centre for Neuromuscular and Neurological Disorders, Western Australian Neuroscience Research Institute, Perth, Australia; Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.
Neuromuscul Disord. 2014 Dec;24(12):1025-35. doi: 10.1016/j.nmd.2014.06.436. Epub 2014 Jun 30.
Although there have been several previous reports of immunohistochemical staining for MHC antigens in muscle biopsies, there appears to be a lack of consensus about its routine use in the diagnostic evaluation of biopsies from patients with suspected inflammatory myopathy. Positive MHC-I staining is nonspecific but is widely used as a marker for inflammatory myopathy, whilst the role of MHC-II staining is not clearly defined. We investigated the sensitivity and specificity of MHC-I and MHC-II immunostaining for the diagnosis of inflammatory myopathy in a large group of biopsies from a single reference laboratory. Positive staining for MHC-I was found to have a high sensitivity in biopsies from patients with inflammatory myopathy but a very low specificity, as it was also common in other non-inflammatory myopathies and neurogenic disorders. On the other hand, MHC-II positivity had a much higher specificity in all major subgroups of inflammatory myopathy, especially inclusion body myositis. The findings indicate that the combination of MHC-I and MHC-II staining results in a higher degree of specificity for the diagnosis of inflammatory myopathy and that in biopsies with inflammation, positive MHC-II staining strongly supports the diagnosis of an immune-mediated myopathy. We recommend that immunohistochemical staining for both MHC-I and MHC-II should be included routinely in the diagnostic evaluation of muscle biopsies from patients with suspected inflammatory myopathy. However, as the sensitivity and interpretation of MHC staining may depend on the technique used, further studies are needed to compare procedures in different centres and develop standardised protocols.
尽管此前已有多篇关于肌肉活检中MHC抗原免疫组化染色的报道，但对于其在疑似炎性肌病患者活检诊断评估中的常规应用，似乎尚未达成共识。MHC-I染色阳性虽不具有特异性，但广泛用作炎性肌病的标志物，而MHC-II染色的作用尚不明确。我们在一家单一参考实验室的大量活检样本中，研究了MHC-I和MHC-II免疫染色对炎性肌病诊断的敏感性和特异性。结果发现，MHC-I染色阳性在炎性肌病患者的活检样本中具有较高的敏感性，但特异性极低，因为在其他非炎性肌病和神经源性疾病中也很常见。另一方面，MHC-II阳性在炎性肌病的所有主要亚组中，尤其是包涵体肌炎中，具有更高的特异性。这些发现表明，MHC-I和MHC-II染色结果相结合，对炎性肌病诊断具有更高的特异性，并且在有炎症的活检样本中，MHC-II染色阳性强烈支持免疫介导性肌病的诊断。我们建议，在对疑似炎性肌病患者的肌肉活检进行诊断评估时，应常规进行MHC-I和MHC-II的免疫组化染色。然而，由于MHC染色的敏感性和解读可能取决于所使用的技术，因此需要进一步研究以比较不同中心的操作方法并制定标准化方案。
