Texas Tech University Health Sciences Center, Lubbock, USA.
J Investig Med High Impact Case Rep. 2022 Jan-Dec;10:23247096221074589. doi: 10.1177/23247096221074589.
Idiopathic inflammatory myopathies (IIMs) are a rare, heterogeneous group of diseases with a characteristic clinical presentation consisting of muscle inflammation and weakness. They often present with accompanying extra-muscular findings, most notably in the skin, lungs, and joints. Inflammatory myopathies are also identified by their characteristic laboratory abnormalities, including a 10- to 50-fold increase in creatinine kinase, elevated liver enzymes, and characteristic electromyography and magnetic resonance imaging findings. Distinct autoimmune markers and clinical phenotypes have advanced our understanding of IIMs and have led to the recognition of 5 distinct entities, each with its unique pathophysiology, autoimmune markers, and clinical features. While autoimmune panels and muscle biopsies help clinicians distinguish one entity from the other, their sensitivity and specificity vary. Of the various inflammatory myopathies, polymyositis remains the most elusive. Often, the diagnosis is ultimately made by combining clinical findings and laboratory data. As our case report illustrates, clinicians must use this constellation of data to initiate treatment for suspected polymyositis despite negative autoimmune panels and negative muscle biopsy.
特发性炎性肌病（IIM）是一组罕见的、异质性疾病，其特征性临床表现为肌肉炎症和无力。它们常伴有伴发的肌肉外表现，最常见于皮肤、肺部和关节。炎性肌病还具有特征性的实验室异常，包括肌酸激酶升高 10-50 倍、肝酶升高以及特征性的肌电图和磁共振成像发现。独特的自身免疫标志物和临床表型提高了我们对 IIM 的认识，并导致了 5 种不同实体的识别，每种实体都有其独特的病理生理学、自身免疫标志物和临床特征。虽然自身免疫谱和肌肉活检有助于临床医生区分不同的实体，但它们的敏感性和特异性存在差异。在各种炎性肌病中，多发性肌炎仍然是最难以捉摸的。通常，最终的诊断是通过结合临床发现和实验室数据来做出的。正如我们的病例报告所示，尽管自身免疫谱和肌肉活检均为阴性，临床医生仍必须使用这组数据来启动疑似多发性肌炎的治疗。
