Smarter Decisions,
Better Care

UpToDate synthesizes the most recent medical information into evidence-based practical recommendations clinicians trust to make the right point of care decisions.

  • Rigorous editorial process: Evidence-based treatment recommendations
  • World-Renowned physician authors: over 5,100 physician authors around the globe
  • Innovative technology: integrates into the workflow; access from EMRs

For more information, click below.


Subscribers log in here


Initial treatment of dermatomyositis and polymyositis in adults

INTRODUCTION

Dermatomyositis (DM) and polymyositis (PM) are classified as idiopathic inflammatory myopathies. Defining the optimal treatment regimens for these disorders has been difficult because of the rarity of these disorders, their highly complex clinical phenotypes, and the limited number of randomized, double-blind clinical trials [1-3].

In addition, understanding of the inflammatory myopathies has evolved over the years, but disease classification schemes have not kept pace. Newer classifications, based upon histologic and serologic distinctions between the different disorders, may help define the natural history of these diseases better, may assist in the design of well-conceived randomized clinical trials, and may lead to the development of rational therapies [4-6].

The initial therapy of DM and PM will be reviewed here. The treatment of recurrent or resistant disease, the clinical manifestations and approach to diagnosis of these disorders in adults, the management of cutaneous manifestations of dermatomyositis, and issues related to DM and PM in children are discussed separately. (See "Treatment of recurrent and resistant dermatomyositis and polymyositis in adults" and "Clinical manifestations and diagnosis of adult dermatomyositis and polymyositis" and "Initial management of cutaneous dermatomyositis" and "Management of refractory cutaneous dermatomyositis" and "Pathogenesis and clinical manifestations of juvenile dermatomyositis and polymyositis" and "Treatment and prognosis of juvenile dermatomyositis and polymyositis".)

PREDICTORS OF OUTCOME

The severity of disease in DM and PM is highly variable, ranging from mild weakness that responds readily to treatment to muscle dysfunction associated with a relentless downhill course that is unresponsive to all treatment modalities. Some clinical and laboratory features are associated with a poorer prognosis.

Clinical predictors — Most studies that have investigated prognosis in the inflammatory myopathies did not distinguish between DM and PM. Many also did not recognize inclusion body myositis, a common mimic of PM that is associated with a worse prognosis but was not defined until the 1980s. (See "Clinical manifestations and diagnosis of inclusion body myositis".)

                                       

Subscribers log in here

To continue reading this article you must have access through your hospital or your group practice, log in to your personal subscription, or purchase a personal subscription. For more information, click below.
Literature review current through: Apr 2013. | This topic last updated: Nov 5, 2012.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2013 UpToDate, Inc.
References
Top
  1. Bunch TW, Worthington JW, Combs JJ, et al. Azathioprine with prednisone for polymyositis. A controlled, clinical trial. Ann Intern Med 1980; 92:365.
  2. Dalakas MC, Illa I, Dambrosia JM, et al. A controlled trial of high-dose intravenous immune globulin infusions as treatment for dermatomyositis. N Engl J Med 1993; 329:1993.
  3. Miller FW, Leitman SF, Cronin ME, et al. Controlled trial of plasma exchange and leukapheresis in polymyositis and dermatomyositis. N Engl J Med 1992; 326:1380.
  4. Troyanov Y, Targoff IN, Tremblay JL, et al. Novel classification of idiopathic inflammatory myopathies based on overlap syndrome features and autoantibodies: analysis of 100 French Canadian patients. Medicine (Baltimore) 2005; 84:231.
  5. Hoogendijk JE, Amato AA, Lecky BR, 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.
  6. Isenberg DA, Allen E, Farewell V, et al. International consensus outcome measures for patients with idiopathic inflammatory myopathies. Development and initial validation of myositis activity and damage indices in patients with adult onset disease. Rheumatology (Oxford) 2004; 43:49.
  7. Joffe MM, Love LA, Leff RL, et al. Drug therapy of the idiopathic inflammatory myopathies: predictors of response to prednisone, azathioprine, and methotrexate and a comparison of their efficacy. Am J Med 1993; 94:379.
  8. Fafalak RG, Peterson MG, Kagen LJ. Strength in polymyositis and dermatomyositis: best outcome in patients treated early. J Rheumatol 1994; 21:643.
  9. Carpenter JR, Bunch TW, Engel AG, O'Brien PC. Survival in polymyositis: corticosteroids and risk factors. J Rheumatol 1977; 4:207.
  10. Dankó K, Ponyi A, Constantin T, et al. Long-term survival of patients with idiopathic inflammatory myopathies according to clinical features: a longitudinal study of 162 cases. Medicine (Baltimore) 2004; 83:35.
  11. Maugars YM, Berthelot JM, Abbas AA, et al. Long-term prognosis of 69 patients with dermatomyositis or polymyositis. Clin Exp Rheumatol 1996; 14:263.
  12. Marie I, Hatron PY, Levesque H, et al. Influence of age on characteristics of polymyositis and dermatomyositis in adults. Medicine (Baltimore) 1999; 78:139.
  13. Lundberg IE, Forbess CJ. Mortality in idiopathic inflammatory myopathies. Clin Exp Rheumatol 2008; 26:S109.
  14. Love LA, Leff RL, Fraser DD, et al. A new approach to the classification of idiopathic inflammatory myopathy: myositis-specific autoantibodies define useful homogeneous patient groups. Medicine (Baltimore) 1991; 70:360.
  15. Plotz PH, Rider LG, Targoff IN, et al. NIH conference. Myositis: immunologic contributions to understanding cause, pathogenesis, and therapy. Ann Intern Med 1995; 122:715.
  16. Stone KB, Oddis CV, Fertig N, et al. Anti-Jo-1 antibody levels correlate with disease activity in idiopathic inflammatory myopathy. Arthritis Rheum 2007; 56:3125.
  17. Miller T, Al-Lozi MT, Lopate G, Pestronk A. Myopathy with antibodies to the signal recognition particle: clinical and pathological features. J Neurol Neurosurg Psychiatry 2002; 73:420.
  18. Kao AH, Lacomis D, Lucas M, et al. Anti-signal recognition particle autoantibody in patients with and patients without idiopathic inflammatory myopathy. Arthritis Rheum 2004; 50:209.
  19. Targoff IN. Immune manifestations of inflammatory muscle disease. Rheum Dis Clin North Am 1994; 20:857.
  20. Winkelmann RK, Mulder DW, Lambert EH, et al. Course of dermatomyositis-polymyositis: comparison of untreated and cortisone-treated patients. Mayo Clin Proc 1968; 43:545.
  21. Drake LA, Dinehart SM, Farmer ER, et al. Guidelines of care for dermatomyositis. American Academy of Dermatology. J Am Acad Dermatol 1996; 34:824.
  22. Hoffman GS, Franck WA, Raddatz DA, Stallones L. Presentation, treatment, and prognosis of idiopathic inflammatory muscle disease in a rural hospital. Am J Med 1983; 75:433.
  23. Robinson LR. AAEM case report #22: polymyositis. Muscle Nerve 1991; 14:310.
  24. Sigurgeirsson B, Lindelöf B, Edhag O, Allander E. Risk of cancer in patients with dermatomyositis or polymyositis. A population-based study. N Engl J Med 1992; 326:363.
  25. Bunch TW. Prednisone and azathioprine for polymyositis: long-term followup. Arthritis Rheum 1981; 24:45.
  26. Dalakas MC, Hohlfeld R. Polymyositis and dermatomyositis. Lancet 2003; 362:971.
  27. Amato AA, Griggs RC. Treatment of idiopathic inflammatory myopathies. Curr Opin Neurol 2003; 16:569.
  28. Relling MV, Gardner EE, Sandborn WJ, et al. Clinical Pharmacogenetics Implementation Consortium guidelines for thiopurine methyltransferase genotype and thiopurine dosing. Clin Pharmacol Ther 2011; 89:387.
  29. Kissel JT, Levy RJ, Mendell JR, Griggs RC. Azathioprine toxicity in neuromuscular disease. Neurology 1986; 36:35.
  30. Giannini M, Callen JP. Treatment of dermatomyositis with methotrexate and prednisone. Arch Dermatol 1979; 115:1251.
  31. Newman ED, Scott DW. The Use of Low-dose Oral Methotrexate in the Treatment of Polymyositis and Dermatomyositis. J Clin Rheumatol 1995; 1:99.
  32. Metzger AL, Bohan A, Goldberg LS, et al. Polymyositis and dermatomyositis: combined methotrexate and corticosteroid therapy. Ann Intern Med 1974; 81:182.
  33. Vleugels RA, Callen JP. Dermatomyositis: current and future therapies. Expert Rev Dermatol 2009; 4:581.
  34. Bronner IM, van der Meulen MF, de Visser M, et al. Long-term outcome in polymyositis and dermatomyositis. Ann Rheum Dis 2006; 65:1456.
  35. Alexanderson H, Lundberg IE. The role of exercise in the rehabilitation of idiopathic inflammatory myopathies. Curr Opin Rheumatol 2005; 17:164.
  36. Dastmalchi M, Alexanderson H, Loell I, et al. Effect of physical training on the proportion of slow-twitch type I muscle fibers, a novel nonimmune-mediated mechanism for muscle impairment in polymyositis or dermatomyositis. Arthritis Rheum 2007; 57:1303.
  37. Hicks JE, Miller F, Plotz P, et al. Isometric exercise increases strength and does not produce sustained creatinine phosphokinase increases in a patient with polymyositis. J Rheumatol 1993; 20:1399.
  38. Marie I, Hachulla E, Chérin P, et al. Opportunistic infections in polymyositis and dermatomyositis. Arthritis Rheum 2005; 53:155.
  39. Fardet L, Rybojad M, Gain M, et al. Incidence, risk factors, and severity of herpesvirus infections in a cohort of 121 patients with primary dermatomyositis and dermatomyositis associated with a malignant neoplasm. Arch Dermatol 2009; 145:889.
  40. Silva CA, Sultan SM, Isenberg DA. Pregnancy outcome in adult-onset idiopathic inflammatory myopathy. Rheumatology (Oxford) 2003; 42:1168.