Myositis Mimics—a Clinical Approach to a Diagnostic Challenge
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Purpose of the Review
Idiopathic inflammatory myopathies (IIMs) encompass a heterogeneous group of disorders generally referred to as myositis. Myositis mimics are common and their overlapping features with IIMs can pose a diagnostic challenge. This review highlights the current knowledge of various myositis mimics, analyzes key distinguishing features from IIMs, and summarizes practical tips in assessing a patient with possible myositis.
A new classification criteria for IIMs has been proposed by the European League against Rheumatism/American College of Rheumatology in 2017. Advances in medical genetics have expanded the spectrum of hereditary myopathies, and effective treatment has become available for some. Magnetic resonance imaging (MRI), although not without limitations, is more widely used to differentiate myositis mimics from IIMs. In the end, one must consider the clinical gestalt in formulating a diagnosis.
A good clinical history, examination, and judicious use and interpretation of ancillary tests are key in approaching a patient with possible IIMs. Monitoring treatment response is also paramount, not only as a clue to reconsidering the diagnosis but also to prevent unwanted side effects and symptom exacerbation from steroids.
KeywordsMyositis Idiopathic inflammatory myopathies Mimics
Compliance with Ethical Standards
Conflict of Interest
Sachiko Takahashi declares that she has no conflict of interest. Michael Nicolle declares that he has no conflict of interest.
Human and Animal Rights and Informed Consent
The authors have not performed any studies involving human or animal subjects in this article.
References and Recommended Reading
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
- 1.•• Lundberg IE, Tjärnlund A, Bottai M, Werth VP, Pilkington C, de Visser M, et al. European League Against Rheumatism/American College of Rheumatology classification criteria for adult and juvenile idiopathic inflammatory myopathies and their major subgroups. Arthritis Rheum. 2017;69:2271–82. https://doi.org/10.1002/art.40320 This article proposes a new classification criteria for adult and juvenile idiopathic inflammatory myopathies and their major subgroups.CrossRefGoogle Scholar
- 2.•• Lundberg IE, de Visser M, Werth VP. Classification of myositis. Nat Rev Rheumatol. 2018;14:269–78. https://doi.org/10.1038/nrrheum.2018.41 This article outlines the historical perspectives of classifying idiopathic inflammatory myopathies; the new 2017 European League Against Rheumatism/American College of Rheumatology classification criteria; and the features of each clinical entities.CrossRefPubMedGoogle Scholar
- 3.Venance SL. Approach to the patient with hyperCKemia. Continuum (Minneap Minn). 2016;22:1803–14. https://doi.org/10.1212/01.CON.0000511069.68640.39.CrossRefGoogle Scholar
- 4.Hoogendijk JE, Amato AA, Lecky BR, Choy EH, Lundberg IE, Rose MR, et al. 119th ENMC international workshop: trial design in adult idiopathic inflammatory myopathies, with the exception of inclusion body myositis, 10-12 October 2003, Naarden, The Netherlands. Neuromuscul Disord. 2004;14:337–45. https://doi.org/10.1016/j.nmd.2004.02.006.CrossRefPubMedGoogle Scholar
- 10.Narayanaswami P, Weiss M, Selcen D, David W, Raynor E, Carter G, et al. Evidence-based guideline summary: diagnosis and treatment of limb-girdle and distal dystrophies: report of the guideline development subcommittee of the American Academy of Neurology and the practice issues review panel of the American Association of Neuromuscular & Electrodiagnostic Medicine. Neurology. 2014;83:1453–63. https://doi.org/10.1212/WNL.0000000000000892.CrossRefPubMedPubMedCentralGoogle Scholar
- 13.Maurer B, Walker UA. Role of MRI in diagnosis and management of idiopathic inflammatory myopathies. Curr Rheumato Rep [Internet]. 2015;17. https://doi.org/10.1007/s11926-015-0544-x [cited 2018 Aug 9].
- 14.Chu ML, Moran E. The limb–girdle muscular dystrophies: is treatment on the horizon? Neurotherapeutics [Internet]. 2018; Available from: http://link.springer.com/10.1007/s13311-018-0648-x [cited 2018 Aug 9].
- 21.Lemmers RJ, Miller DG, van der Maarel SM. Facioscapulohumeral Muscular Dystrophy. In: Adam MP, Ardinger HH, Pagon RA, Wallace SE, Bean LJ, Stephens K, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993. [cited 2018 Aug 12]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK1443/.Google Scholar
- 36.Selva-O’Callaghan A, Alvarado-Cardenas M, Pinal-Fernández I, Trallero-Araguás E, Milisenda JC, Martínez MÁ, et al. Statin-induced myalgia and myositis: an update on pathogenesis and clinical recommendations. Expert Rev Clin Immunol. 2018;14:215–24. https://doi.org/10.1080/1744666X.2018.1440206.CrossRefPubMedPubMedCentralGoogle Scholar
- 39.Christopher-Stine L, Casciola-Rosen LA, Hong G, Chung T, Corse AM, Mammen AL. A novel autoantibody recognizing 200-kd and 100-kd proteins is associated with an immune-mediated necrotizing myopathy. Arthritis Rheum. 2010;62:2757–66. https://doi.org/10.1002/art.27572.CrossRefPubMedPubMedCentralGoogle Scholar
- 40.Mammen AL, Chung T, Christopher-Stine L, Rosen P, Rosen A, Doering KR, et al. Autoantibodies against 3-hydroxy-3-methylglutaryl-coenzyme A reductase in patients with statin-associated autoimmune myopathy. Arthritis Rheum. 2011;63:713–21. https://doi.org/10.1002/art.30156.CrossRefPubMedPubMedCentralGoogle Scholar
- 48.• Bourgeois-Vionnet J, Joubert B, Bernard E, Sia MA, Pante V, Fabien N, et al. Nivolumab-induced myositis: a case report and a literature review. J Neurol Sci. 2018;387:51–3. https://doi.org/10.1016/j.jns.2018.01.030 Case report of novel adverse event associated with Nivolimumab, an immune checkpoint inhibitor, utilized in cancer therapy.CrossRefPubMedGoogle Scholar
- 49.• Kolb NA, Trevino CR, Waheed W, Sobhani F, Landry KK, Thomas AA, et al. Neuromuscular complications of immune checkpoint inhibitor therapy: neuromuscular complications of immune checkpoint inhibitor therapy. Muscle Nerve. 2018;58:10–22. https://doi.org/10.1002/mus.26070 Review article of newly discovered immune-mediated neuromuscular disorders (including inflammatory myopathy) associated with immune checkpoint inhibitors.CrossRefGoogle Scholar
- 50.• Kao JC, Brickshawana A, Liewluck T. Neuromuscular complications of programmed cell death-1 (PD-1) inhibitors. Curr Neurol Neurosci Rep [Internet]. 2018;18 [cited 2018 Sep 8] Available from: http://link.springer.com/10.1007/s11910-018-0878-7. Review article of newly discovered immune-mediated neuromuscular disorders (including inflammatory myopathy) associated with immune checkpoint inhibitors.
- 54.Tajima K, Mashita K, Yamane T, Yoshikawa H, Kawamura S, Kang J, et al. Thyrotoxic myopathy associated with subacute thyroiditis. Clin Endocrinol. 1984;20:307–12. https://doi.org/10.1111/j.1365-2265.1984.tb00087.x.CrossRefGoogle Scholar
- 62.Hajjar K, Hagenacker T. Neuromuscular disorder as initial manifestation of secondary hyperparathyroidism—a case report. Eur J Transl Myol [Internet]. 2017;27 [cited 2018 Jul 28] Available from: http://pagepressjournals.org/index.php/bam/article/view/6100.
- 64.Dai CL, Sun ZJ, Zhang X, Qiu MC. Elevated muscle enzymes and muscle biopsy in idiopathic hypoparathyroidism patients. J Endocrinol Investig [Internet]. 2012; [cited 2018 Jul 28]: Available from: http://www.jendocrinolinvest.it/jei/en/abstract.cfm?articolo_id=7679.
- 78.Malik A, Hayat G, Kalia JS, Guzman MA. Idiopathic inflammatory myopathies: clinical approach and management. Front Neurol [Internet]. 2016;7 [cited 2018 Aug 12] Available from: http://journal.frontiersin.org/Article/10.3389/fneur.2016.00064/abstract.
- 82.Dumitru D, Amato AA, Zwarts MJ, editors. Electrodiagnostic medicine. 2nd ed. Philadelphia: Hanley & Belfus; 2002.Google Scholar
- 83.Tai H, Cui L, Guan Y, Liu M, Li X, Shen D, et al. Correlation of creatine kinase levels with clinical features and survival in amyotrophic lateral sclerosis. Front Neurol [Internet]. 2017:8 [cited 2018 Aug 10] Available from: http://journal.frontiersin.org/article/10.3389/fneur.2017.00322/full.
- 85.Michelle EH, Mammen AL. Myositis mimics. Curr Rheumatol Rep [Internet]. 2015;17 [cited 2018 Aug 12] Available from: http://link.springer.com/10.1007/s11926-015-0541-0.