- Author: Alisa N Femia, MD; Chief Editor: Herbert S Diamond, MD more...
The workup for dermatomyositis may include selected laboratory tests and diagnostic imaging (eg, magnetic resonance imaging [MRI], chest radiography, ultrasonography, electromyography [EMG], or computed tomography [CT]), as well as muscle and skin biopsy and other tests as appropriate.
In adult patients with dermatomyositis, assessment for malignancy should be performed upon initial diagnosis and repeated at least annually for 3 years. The risk of malignancy increases with age. The exact testing order should be based on the patient's sex, age, and race; however, testing beyond age-appropriate screening is most often recommended.
Muscle enzyme levels are often abnormal during the course of dermatomyositis, except in patients with amyopathic dermatomyositis (ADM). The most sensitive/specific enzyme abnormality is elevated creatine kinase (CK), but aldolase studies and other tests (eg, for aspartate aminotransferase [AST] or lactic dehydrogenase [LDH]) may also yield abnormal results.
At times, the elevation of the enzymes precedes the appearance of clinical evidence of myositis. Thus, if a patient who is presumably stable develops an elevation of an enzyme that was previously within the reference range, the clinician should assess the possibility of a flare of the muscle disease.
Several serologic abnormalities have been identified and may be helpful in the classification of subtypes for prognosis, but they are not used for routine diagnosis. As a group, these antibodies have been termed myositis-specific antibodies (MSAs). These autoantibodies occur in about 30% of all patients with dermatomyositis or polymyositis.
A positive antinuclear antibody (ANA) finding is common in patients with dermatomyositis, but is not necessary for diagnosis.
Anti–Mi-2 antibodies are highly specific for dermatomyositis, but sensitivity is low; only 25% of patients with dermatomyositis demonstrate these antibodies. These autoantibodies are associated with acute-onset classic dermatomyositis, including the V-neck sign and shawl rash (poikiloderma), as well as a relatively good prognosis.
Anti–Jo-1 (antihistidyl transfer RNA [t-RNA] synthetase) antibodies are more common in patients with polymyositis, but may occur in patients with dermatomyositis. They are associated with pulmonary involvement (interstitial lung disease), Raynaud phenomenon, arthritis, and mechanic's hands in the setting of the anti-synthetase syndrome.
Other MSAs include anti-signal recognition protein (anti-SRP), which is associated with severe myositis; anti–PM-Scl and anti-Ku, which are associated with overlapping features of myositis and scleroderma; and anti-NXP-2, which is associated with calcinosis in the juvenile population, and more recently, in the adult population as well.
An autoantibody directed against a 155-kd protein known as anti-p155/140 or antitranscription intermediary factor (TIF)-1γ, has been associated with malignancy in dermatomyositis.[45, 46, 47] Subsequently, the presence of anti-p155/140 antibodies targeting TIF-1α in addition to TIF-1γ, rather than TIF-1γ alone, was shown to be associated with malignancy. Although these findings may be used to help prognosticate patients with dermatomyositis in the future, these antibodies may be found in patients without cancer, and serology is not currently used routinely to help diagnose cancer-associated dermatomyositis.
A 140-kd polypeptide autoantibody, known as anti-CADM140 or antimelanoma differentiation antigen (MDA)–5, has been associated with clinically amyopathic dermatomyositis (CADM) and rapidly progressive interstitial lung disease, especially, but not exclusively, in the Asian population.[49, 50, 51, 52, 53] In the United States population, skin and mucosal ulcerations and/or tender palmar papules (which are likely due to vasculopathy), along with hair loss, hand swelling, and arthritis/arthralgias, have been associated with circulating anti-MDA5 antibodies.
A study of 11 patients with CADM suggests that levels of anti-MDA5 antibodies may fluctuate over time and may correlate with disease activity. In addition, in the juvenile dermatomyositis population, anti-(MDA)-5 antibodies were recently found to be associated with skin and oral ulceration, arthritis, and milder muscle involvement in a cohort of United Kingdom patients.
MRI may be useful in assessing for the presence of an inflammatory myopathy in patients without weakness. It can assist in differentiating steroid myopathy from continued inflammation and may serve as a guide in selecting a muscle biopsy site. Ultrasonography of the muscles has also been suggested for evaluation but has not been widely accepted.
Electromyography (EMG) is a means of detecting muscle inflammation and damage and has, at times, been useful in selecting a muscle biopsy site. Since the introduction of muscle MRI, EMG has been obtained less commonly in this setting.
A barium swallow allows evaluation of esophageal dysmotility.
CT scanning of the chest, abdomen, and pelvis is useful in the evaluation of potential malignancy that might be associated with dermatomyositis.
Transvaginal ultrasonography of the pelvis is particularly important for malignancy screening in women, given the strong association between ovarian cancer and dermatomyositis. Mammography is also useful in women for the evaluation of a potential malignancy.
Other tests may include the following:
Pulmonary function studies with diffusion capacity
Esophageal manometry (in selected patients)
Age-related colonoscopy and fecal-occult blood testing for malignancy screening
Papanicolaou smear in women for malignancy screening
Cancer antigen 125 (CA-125) and CA-19-9 for malignancy screening
Muscle biopsy, either open or via needle, may enhance the clinician's ability to diagnose dermatomyositis. The biopsy results may be useful in differentiating steroid myopathy from active inflammatory myopathy when patients have been on corticosteroid therapy but are still weak.
Skin biopsy reveals an interface dermatitis that is difficult to differentiate from lupus erythematosus (see the image below). Vacuolar changes of the columnar epithelium and lymphocytic inflammatory infiltrates at the dermal-epidermal junction basement membrane can occur. Mucin deposition in the dermis is also characteristic.
Findings on muscle biopsy can be diagnostic. Muscle biopsy in patients with dermatomyositis reveals perivascular and interfascicular inflammatory infiltrates with adjoining groups of muscle fiber degeneration/regeneration (see the image below). This contrasts with polymyositis infiltrates, which are mainly intrafascicular (endomysial inflammation) with scattered individual muscle fiber necrosis.
Although inflammation is the histologic hallmark of dermatomyositis, polymyositis, and inclusion-body myositis, dermatomyositis is the only 1 of the 3 that shows perifascicular atrophy. In addition, many fibers undergo degeneration and necrosis that cause them to lose their staining ability; therefore, they are termed ghost fibers. When these changes are associated with collections of inflammatory cells around the blood vessels, the diagnosis of dermatomyositis is certain (see the images below).
Callen JP. Dermatomyositis. Lancet. 2000 Jan 1. 355(9197):53-7. [Medline].
Callen JP, Wortmann RL. Dermatomyositis. Clin Dermatol. 2006 Sep-Oct. 24(5):363-73. [Medline].
Kasteler JS, Callen JP. Scalp involvement in dermatomyositis. Often overlooked or misdiagnosed. JAMA. 1994 Dec 28. 272(24):1939-41. [Medline].
Airio A, Pukkala E, Isomäki H. Elevated cancer incidence in patients with dermatomyositis: a population based study. J Rheumatol. 1995 Jul. 22(7):1300-3. [Medline].
Chow WH, Gridley G, Mellemkjaer L, McLaughlin JK, Olsen JH, Fraumeni JF Jr. Cancer risk following polymyositis and dermatomyositis: a nationwide cohort study in Denmark. Cancer Causes Control. 1995 Jan. 6(1):9-13. [Medline].
Hill CL, Zhang Y, Sigurgeirsson B, et al. Frequency of specific cancer types in dermatomyositis and polymyositis: a population-based study. Lancet. 2001 Jan 13. 357(9250):96-100. [Medline].
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 Feb 6. 326(6):363-7. [Medline].
Antiochos BB, Brown LA, Li Z, Tosteson TD, Wortmann RL, Rigby WF. Malignancy is associated with dermatomyositis but not polymyositis in Northern New England, USA. J Rheumatol. 2009 Dec. 36(12):2704-10. [Medline].
Fardet L, Dupuy A, Gain M, et al. Factors associated with underlying malignancy in a retrospective cohort of 121 patients with dermatomyositis. Medicine (Baltimore). 2009 Mar. 88(2):91-7. [Medline].
Bohan A, Peter JB. Polymyositis and dermatomyositis (second of two parts). N Engl J Med. 1975 Feb 20. 292(8):403-7. [Medline].
Bohan A, Peter JB. Polymyositis and dermatomyositis (first of two parts). N Engl J Med. 1975 Feb 13. 292(7):344-7. [Medline].
Sontheimer RD. Would a new name hasten the acceptance of amyopathic dermatomyositis (dermatomyositis siné myositis) as a distinctive subset within the idiopathic inflammatory dermatomyopathies spectrum of clinical illness?. J Am Acad Dermatol. 2002 Apr. 46(4):626-36. [Medline].
Bendewald MJ, Wetter DA, Li X, Davis MD. Incidence of dermatomyositis and clinically amyopathic dermatomyositis: a population-based study in Olmsted County, Minnesota. Arch Dermatol. 2010 Jan. 146(1):26-30. [Medline]. [Full Text].
Klein RQ, Teal V, Taylor L, Troxel AB, Werth VP. Number, characteristics, and classification of patients with dermatomyositis seen by dermatology and rheumatology departments at a large tertiary medical center. J Am Acad Dermatol. 2007 Dec. 57(6):937-43. [Medline].
Sun Y, Liu Y, Yan B, Shi G. Interstitial lung disease in clinically amyopathic dermatomyositis (CADM) patients: a retrospective study of 41 Chinese Han patients. Rheumatol Int. 2013 May. 33(5):1295-302. [Medline].
Gerami P, Schope JM, McDonald L, Walling HW, Sontheimer RD. A systematic review of adult-onset clinically amyopathic dermatomyositis (dermatomyositis siné myositis): a missing link within the spectrum of the idiopathic inflammatory myopathies. J Am Acad Dermatol. 2006 Apr. 54(4):597-613. [Medline].
Levine TD. Rituximab in the treatment of dermatomyositis: an open-label pilot study. Arthritis Rheum. 2005 Feb. 52(2):601-7. [Medline].
Chung L, Genovese MC, Fiorentino DF. A pilot trial of rituximab in the treatment of patients with dermatomyositis. Arch Dermatol. 2007 Jun. 143(6):763-7. [Medline].
Banker BQ, Victor M. Dermatomyositis (systemic angiopathy) of childhood. Medicine (Baltimore). 1966 Jul. 45(4):261-89. [Medline].
Werth VP, Callen JP, Ang G, Sullivan KE. Associations of tumor necrosis factor alpha and HLA polymorphisms with adult dermatomyositis: implications for a unique pathogenesis. J Invest Dermatol. 2002 Sep. 119(3):617-20. [Medline].
Pachman LM, Veis A, Stock S, et al. Composition of calcifications in children with juvenile dermatomyositis: association with chronic cutaneous inflammation. Arthritis Rheum. 2006 Oct. 54(10):3345-50. [Medline]. [Full Text].
Lutz J, Huwiler KG, Fedczyna T, et al. Increased plasma thrombospondin-1 (TSP-1) levels are associated with the TNF alpha-308A allele in children with juvenile dermatomyositis. Clin Immunol. 2002 Jun. 103(3 Pt 1):260-3. [Medline].
Chen S, Wang Q, Wu Z, Wu Q, Li P, Li Y, et al. Associations between TNF-a-308A/G Polymorphism and Susceptibility with Dermatomyositis: A Meta-Analysis. PLoS One. 2014. 9(8):e102841. [Medline]. [Full Text].
Daoud MS, Gibson LE, Pittelkow MR. Hydroxyurea dermopathy: a unique lichenoid eruption complicating long-term therapy with hydroxyurea. J Am Acad Dermatol. 1997 Feb. 36(2 Pt 1):178-82. [Medline].
Noël B. Lupus erythematosus and other autoimmune diseases related to statin therapy: a systematic review. J Eur Acad Dermatol Venereol. 2007 Jan. 21(1):17-24. [Medline].
O'Hanlon T, Koneru B, Bayat E, Love L, Targoff I, Malley J, et al. Immunogenetic differences between Caucasian women with and those without silicone implants in whom myositis develops. Arthritis Rheum. 2004 Nov. 50(11):3646-50. [Medline].
Callen JP, Hyla JF, Bole GG Jr, Kay DR. The relationship of dermatomyositis and polymyositis to internal malignancy. Arch Dermatol. 1980 Mar. 116(3):295-8. [Medline].
Buchbinder R, Forbes A, Hall S, Dennett X, Giles G. Incidence of malignant disease in biopsy-proven inflammatory myopathy. A population-based cohort study. Ann Intern Med. 2001 Jun 19. 134(12):1087-95. [Medline].
Chow WH, Gridley G, Mellemkjaer L, McLaughlin JK, Olsen JH, Fraumeni JF Jr. Cancer risk following polymyositis and dermatomyositis: a nationwide cohort study in Denmark. Cancer Causes Control. 1995 Jan. 6(1):9-13. [Medline].
Limaye V, Luke C, Tucker G, Hill C, Lester S, Blumbergs P, et al. The incidence and associations of malignancy in a large cohort of patients with biopsy-determined idiopathic inflammatory myositis. Rheumatol Int. 2013 Apr. 33(4):965-71. [Medline].
So MW, Koo BS, Kim YG, Lee CK, Yoo B. Idiopathic inflammatory myopathy associated with malignancy: a retrospective cohort of 151 Korean patients with dermatomyositis and polymyositis. J Rheumatol. 2011 Nov. 38(11):2432-5. [Medline].
Zantos D, Zhang Y, Felson D. The overall and temporal association of cancer with polymyositis and dermatomyositis. J Rheumatol. 1994 Oct. 21(10):1855-9. [Medline].
Stockton D, Doherty VR, Brewster DH. Risk of cancer in patients with dermatomyositis or polymyositis, and follow-up implications: a Scottish population-based cohort study. Br J Cancer. 2001 Jul 6. 85(1):41-5. [Medline]. [Full Text].
Femia AN, Vleugels RA, Callen JP. Cutaneous dermatomyositis: an updated review of treatment options and internal associations. Am J Clin Dermatol. 2013 Aug. 14(4):291-313. [Medline].
Huang YL, Chen YJ, Lin MW, Wu CY, Liu PC, Chen TJ, et al. Malignancies associated with dermatomyositis and polymyositis in Taiwan: a nationwide population-based study. Br J Dermatol. 2009 Oct. 161(4):854-60. [Medline].
Kuo CF, See LC, Yu KH, Chou IJ, Chang HC, Chiou MJ, et al. Incidence, cancer risk and mortality of dermatomyositis and polymyositis in Taiwan: a nationwide population study. Br J Dermatol. 2011 Dec. 165(6):1273-9. [Medline].
Liu WC, Ho M, Koh WP, Tan AW, Ng PP, Chua SH, et al. An 11-year review of dermatomyositis in Asian patients. Ann Acad Med Singapore. 2010 Nov. 39(11):843-7. [Medline].
Chen D, Yuan S, Wu X, Li H, Qiu Q, Zhan Z, et al. Incidence and predictive factors for malignancies with dermatomyositis: a cohort from southern China. Clin Exp Rheumatol. 2014 Jul 28. [Medline].
Valenzuela A, Chung L, Casciola-Rosen L, Fiorentino D. Identification of clinical features and autoantibodies associated with calcinosis in dermatomyositis. JAMA Dermatol. 2014 Jul. 150(7):724-9. [Medline].
Rai SK, Choi HK, Sayre EC, Aviña-Zubieta JA. Risk of myocardial infarction and ischaemic stroke in adults with polymyositis and dermatomyositis: a general population-based study. Rheumatology (Oxford). 2015 Sep 30. [Medline].
Lee CW, Muo CH, Liang JA, Sung FC, Hsu CY, Kao CH. Increased osteoporosis risk in dermatomyositis or polymyositis independent of the treatments: a population-based cohort study with propensity score. Endocrine. 2015 Oct 1. [Medline].
Seidler AM, Gottlieb AB. Dermatomyositis induced by drug therapy: a review of case reports. J Am Acad Dermatol. 2008 Nov. 59(5):872-80. [Medline].
Labirua-Iturburu A, Selva-O'Callaghan A, Vincze M, Dankó K, Vencovsky J, Fisher B, et al. Anti-PL-7 (anti-threonyl-tRNA synthetase) antisynthetase syndrome: clinical manifestations in a series of patients from a European multicenter study (EUMYONET) and review of the literature. Medicine (Baltimore). 2012 Jul. 91(4):206-11. [Medline].
Trallero-Araguás E, Labrador-Horrillo M, Selva-O'Callaghan A, et al. Cancer-associated myositis and anti-p155 autoantibody in a series of 85 patients with idiopathic inflammatory myopathy. Medicine (Baltimore). 2010 Jan. 89(1):47-52. [Medline].
Trallero-Araguás E, Rodrigo-Pendás JÁ, Selva-O'Callaghan A, Martínez-Gómez X, Bosch X, Labrador-Horrillo M, et al. Usefulness of anti-p155 autoantibody for diagnosing cancer-associated dermatomyositis: a systematic review and meta-analysis. Arthritis Rheum. 2012 Feb. 64(2):523-32. [Medline].
Hamaguchi Y, Kuwana M, Hoshino K, Hasegawa M, Kaji K, Matsushita T, et al. Clinical correlations with dermatomyositis-specific autoantibodies in adult Japanese patients with dermatomyositis: a multicenter cross-sectional study. Arch Dermatol. 2011 Apr. 147(4):391-8. [Medline].
Fujimoto M, Hamaguchi Y, Kaji K, Matsushita T, Ichimura Y, Kodera M, et al. Myositis-specific anti-155/140 autoantibodies target transcription intermediary factor 1 family proteins. Arthritis Rheum. 2012 Feb. 64(2):513-22. [Medline].
Sato S, Hirakata M, Kuwana M, Suwa A, Inada S, Mimori T, et al. Autoantibodies to a 140-kd polypeptide, CADM-140, in Japanese patients with clinically amyopathic dermatomyositis. Arthritis Rheum. 2005 May. 52(5):1571-6. [Medline].
Sato S, Hoshino K, Satoh T, Fujita T, Kawakami Y, Fujita T, et al. RNA helicase encoded by melanoma differentiation-associated gene 5 is a major autoantigen in patients with clinically amyopathic dermatomyositis: Association with rapidly progressive interstitial lung disease. Arthritis Rheum. 2009 Jul. 60(7):2193-200. [Medline].
Hoshino K, Muro Y, Sugiura K, Tomita Y, Nakashima R, Mimori T. Anti-MDA5 and anti-TIF1-gamma antibodies have clinical significance for patients with dermatomyositis. Rheumatology (Oxford). 2010 Sep. 49(9):1726-33. [Medline].
Chaisson NF, Paik J, Orbai AM, Casciola-Rosen L, Fiorentino D, Danoff S, et al. A novel dermato-pulmonary syndrome associated with MDA-5 antibodies: report of 2 cases and review of the literature. Medicine (Baltimore). 2012 Jul. 91(4):220-8. [Medline]. [Full Text].
Cuesta-Mateos C, Colom-Fernández B, Portero-Sainz I, Tejedor R, García-García C, Concha-Garzón MJ, et al. Autoantibodies against TIF-1-? and CADM-140 in Spanish patients with clinically amyopathic dermatomyositis (CADM): clinical significance and diagnostic utility. J Eur Acad Dermatol Venereol. 2014 Jul 28. [Medline].
Fiorentino D, Chung L, Zwerner J, Rosen A, Casciola-Rosen L. The mucocutaneous and systemic phenotype of dermatomyositis patients with antibodies to MDA5 (CADM-140): a retrospective study. J Am Acad Dermatol. 2011 Jul. 65(1):25-34. [Medline]. [Full Text].
Muro Y, Sugiura K, Hoshino K, Akiyama M. Disappearance of anti-MDA-5 autoantibodies in clinically amyopathic DM/interstitial lung disease during disease remission. Rheumatology (Oxford). 2012 May. 51(5):800-4. [Medline].
Tansley SL, Betteridge ZE, Gunawardena H, Jacques TS, Owens CM, Pilkington C, et al. Anti-MDA5 autoantibodies in juvenile dermatomyositis identify a distinct clinical phenotype: a prospective cohort study. Arthritis Res Ther. 2014 Jul 2. 16(4):R138. [Medline].
Smith ES, Hallman JR, DeLuca AM, Goldenberg G, Jorizzo JL, Sangueza OP. Dermatomyositis: a clinicopathological study of 40 patients. Am J Dermatopathol. 2009 Feb. 31(1):61-7. [Medline].
Ang GC, Werth VP. Combination antimalarials in the treatment of cutaneous dermatomyositis: a retrospective study. Arch Dermatol. 2005 Jul. 141(7):855-9. [Medline].
Iorizzo LJ 3rd, Jorizzo JL. The treatment and prognosis of dermatomyositis: an updated review. J Am Acad Dermatol. 2008 Jul. 59(1):99-112. [Medline].
Chérin P. [Current therapy for polymyositis and dermatomyositis]. Rev Med Interne. 2008 Jun. 29 Spec No 2:9-14. [Medline].
Hengstman GJ, van den Hoogen FH, van Engelen BG. Treatment of the inflammatory myopathies: update and practical recommendations. Expert Opin Pharmacother. 2009 May. 10(7):1183-90. [Medline].
Choy EH, Hoogendijk JE, Lecky B, Winer JB. Immunosuppressant and immunomodulatory treatment for dermatomyositis and polymyositis. Cochrane Database Syst Rev. 2005 Jul 20. CD003643. [Medline].
Edge JC, Outland JD, Dempsey JR, Callen JP. Mycophenolate mofetil as an effective corticosteroid-sparing therapy for recalcitrant dermatomyositis. Arch Dermatol. 2006 Jan. 142(1):65-9. [Medline].
Kasteler JS, Callen JP. Low-dose methotrexate administered weekly is an effective corticosteroid-sparing agent for the treatment of the cutaneous manifestations of dermatomyositis. J Am Acad Dermatol. 1997 Jan. 36(1):67-71. [Medline].
Villalba L, Hicks JE, Adams EM, et al. Treatment of refractory myositis: a randomized crossover study of two new cytotoxic regimens. Arthritis Rheum. 1998 Mar. 41(3):392-9. [Medline].
Boswell JS, Costner MI. Leflunomide as adjuvant treatment of dermatomyositis. J Am Acad Dermatol. 2008 Mar. 58(3):403-6. [Medline].
Newman ED, Scott DW. The Use of Low-dose Oral Methotrexate in the Treatment of Polymyositis and Dermatomyositis. J Clin Rheumatol. 1995 Apr. 1(2):99-102. [Medline].
Bunch TW. Prednisone and azathioprine for polymyositis: long-term followup. Arthritis Rheum. 1981 Jan. 24(1):45-8. [Medline].
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 Dec 30. 329(27):1993-2000. [Medline].
Danieli MG, Calcabrini L, Calabrese V, Marchetti A, Logullo F, Gabrielli A. Intravenous immunoglobulin as add on treatment with mycophenolate mofetil in severe myositis. Autoimmun Rev. 2009 Dec. 9(2):124-7. [Medline].
Marie I, Menard JF, Hatron PY, et al. Intravenous immunoglobulins for steroid-refractory esophageal involvement related to polymyositis and dermatomyositis: a series of 73 patients. Arthritis Care Res (Hoboken). 2010 Dec. 62(12):1748-55. [Medline].
Oddis CV, Reed AM, Aggarwal R, Rider LG, Ascherman DP, Levesque MC, et al. Rituximab in the treatment of refractory adult and juvenile dermatomyositis and adult polymyositis: a randomized, placebo-phase trial. Arthritis Rheum. 2013 Feb. 65(2):314-24. [Medline]. [Full Text].
Aggarwal R, Bandos A, Reed AM, Ascherman DP, Barohn RJ, Feldman BM, et al. Predictors of clinical improvement in rituximab-treated refractory adult and juvenile dermatomyositis and adult polymyositis. Arthritis Rheumatol. 2014 Mar. 66(3):740-9. [Medline]. [Full Text].
Ge Y, Zhou H, Shi J, Ye B, Peng Q, Lu X, et al. The efficacy of tacrolimus in patients with refractory dermatomyositis/polymyositis: a systematic review. Clin Rheumatol. 2015 Sep 2. [Medline].
Pelle MT, Callen JP. Adverse cutaneous reactions to hydroxychloroquine are more common in patients with dermatomyositis than in patients with cutaneous lupus erythematosus. Arch Dermatol. 2002 Sep. 138(9):1231-3; discussion 1233. [Medline].
Woo TY, Callen JP, Voorhees JJ, et al. Cutaneous lesions of dermatomyositis are improved by hydroxychloroquine. J Am Acad Dermatol. 1984 Apr. 10(4):592-600. [Medline].
Zieglschmid-Adams ME, Pandya AG, Cohen SB, Sontheimer RD. Treatment of dermatomyositis with methotrexate. J Am Acad Dermatol. 1995 May. 32(5 Pt 1):754-7. [Medline].
Majithia V, Harisdangkul V. Mycophenolate mofetil (CellCept): an alternative therapy for autoimmune inflammatory myopathy. Rheumatology (Oxford). 2005 Mar. 44(3):386-9. [Medline].
Pisoni CN, Cuadrado MJ, Khamashta MA, Hughes GR, D'Cruz DP. Mycophenolate mofetil treatment in resistant myositis. Rheumatology (Oxford). 2007 Mar. 46(3):516-8. [Medline].
Rowin J, Amato AA, Deisher N, Cursio J, Meriggioli MN. Mycophenolate mofetil in dermatomyositis: is it safe?. Neurology. 2006 Apr 25. 66(8):1245-7. [Medline].
Waldman MA, Callen JP. Self-resolution of Epstein-Barr virus-associated B-cell lymphoma in a patient with dermatomyositis following withdrawal of mycophenolate mofetil and methotrexate. J Am Acad Dermatol. 2004 Aug. 51(2 Suppl):S124-30. [Medline].
Nadiminti U, Arbiser JL. Rapamycin (sirolimus) as a steroid-sparing agent in dermatomyositis. J Am Acad Dermatol. 2005 Feb. 52(2 Suppl 1):17-9. [Medline].
Cohen JB. Cutaneous involvement of dermatomyositis can respond to Dapsone therapy. Int J Dermatol. 2002 Mar. 41(3):182-4. [Medline].
Shimojima Y, Ishii W, Kato T, Hoshi K, Matsuda M, Hashimoto T, et al. Intractable skin necrosis and interstitial pneumonia in amyopathic dermatomyositis, successfully treated with cyclosporin A. Intern Med. 2003 Dec. 42(12):1253-8. [Medline].
Kampylafka EI, Kosmidis ML, Panagiotakos DB, Dalakas M, Moutsopoulos HM, Tzioufas AG. The effect of intravenous immunoglobulin (IVIG) treatment on patients with dermatomyositis: a 4-year follow-up study. Clin Exp Rheumatol. 2012 May-Jun. 30(3):397-401. [Medline].
Danieli MG, Moretti R, Gambini S, Paolini L, Gabrielli A. Open-label study on treatment with 20 % subcutaneous IgG administration in polymyositis and dermatomyositis. Clin Rheumatol. 2014 Apr. 33(4):531-6. [Medline].
Oliveri MB, Palermo R, Mautalen C, Hübscher O. Regression of calcinosis during diltiazem treatment in juvenile dermatomyositis. J Rheumatol. 1996 Dec. 23(12):2152-5. [Medline].
Ambler GR, Chaitow J, Rogers M, McDonald DW, Ouvrier RA. Rapid improvement of calcinosis in juvenile dermatomyositis with alendronate therapy. J Rheumatol. 2005 Sep. 32(9):1837-9. [Medline].
Slimani S, Abdessemed A, Haddouche A, Ladjouze-Rezig A. Complete resolution of universal calcinosis in a patient with juvenile dermatomyositis using pamidronate. Joint Bone Spine. 2010 Jan. 77(1):70-2. [Medline].
Balin SJ, Wetter DA, Andersen LK, Davis MD. Calcinosis cutis occurring in association with autoimmune connective tissue disease: the Mayo Clinic experience with 78 patients, 1996-2009. Arch Dermatol. 2012 Apr. 148(4):455-62. [Medline].
Alemo Munters L, Dastmalchi M, Andgren V, Emilson C, Bergegård J, Regardt M, et al. Improvement in health and possible reduction in disease activity using endurance exercise in patients with established polymyositis and dermatomyositis: a multicenter randomized controlled trial with a 1-year open extension followup. Arthritis Care Res (Hoboken). 2013 Dec. 65(12):1959-68. [Medline].
Alexanderson H, Munters LA, Dastmalchi M, Loell I, Heimbürger M, Opava CH, et al. Resistive home exercise in patients with recent-onset polymyositis and dermatomyositis -- a randomized controlled single-blinded study with a 2-year followup. J Rheumatol. 2014 Jun. 41(6):1124-32. [Medline].
Anyanwu CO, Fiorentino DF, Chung L, Dzuong C, Wang Y, Okawa J, et al. Validation of the Cutaneous Dermatomyositis Disease Area and Severity Index: characterizing disease severity and assessing responsiveness to clinical change. Br J Dermatol. 2015 Oct. 173 (4):969-74. [Medline].
Klein RQ, Bangert CA, Costner M, et al. Comparison of the reliability and validity of outcome instruments for cutaneous dermatomyositis. Br J Dermatol. 2008 Sep. 159(4):887-94. [Medline]. [Full Text].
Di Rollo D, Abeni D, Tracanna M, Capo A, Amerio P. Cancer risk in dermatomyositis: a systematic review of the literature. G Ital Dermatol Venereol. 2014 Jun 30. [Medline].
Metzger AL, Bohan A, Goldberg LS, Bluestone R, Pearson CM. Polymyositis and dermatomyositis: combined methotrexate and corticosteroid therapy. Ann Intern Med. 1974 Aug. 81(2):182-9. [Medline].
Marie I, Hachulla E, Hatron PY, Hellot MF, Levesque H, Devulder B, et al. Polymyositis and dermatomyositis: short term and longterm outcome, and predictive factors of prognosis. J Rheumatol. 2001 Oct. 28(10):2230-7. [Medline].
Efthimiou P, Schwartzman S, Kagen LJ. Possible role for tumour necrosis factor inhibitors in the treatment of resistant dermatomyositis and polymyositis: a retrospective study of eight patients. Ann Rheum Dis. 2006 Sep. 65(9):1233-6. [Medline]. [Full Text].
Iannone F, Scioscia C, Falappone PC, Covelli M, Lapadula G. Use of etanercept in the treatment of dermatomyositis: a case series. J Rheumatol. 2006 Sep. 33(9):1802-4. [Medline].
Dastmalchi M, Grundtman C, Alexanderson H, Mavragani CP, Einarsdottir H, Helmers SB, et al. A high incidence of disease flares in an open pilot study of infliximab in patients with refractory inflammatory myopathies. Ann Rheum Dis. 2008 Dec. 67(12):1670-7. [Medline].
Hengstman GJ, De Bleecker JL, Feist E, Vissing J, Denton CP, Manoussakis MN, et al. Open-label trial of anti-TNF-alpha in dermato- and polymyositis treated concomitantly with methotrexate. Eur Neurol. 2008. 59(3-4):159-63. [Medline].
Liu SW, Velez NF, Lam C, Femia A, Granter SR, Townsend HB, et al. Dermatomyositis induced by anti-tumor necrosis factor in a patient with juvenile idiopathic arthritis. JAMA Dermatol. 2013 Oct. 149(10):1204-8. [Medline].
Fathi M, Vikgren J, Boijsen M, Tylen U, Jorfeldt L, Tornling G, et al. Interstitial lung disease in polymyositis and dermatomyositis: longitudinal evaluation by pulmonary function and radiology. Arthritis Rheum. 2008 May 15. 59(5):677-85. [Medline].
Linos E, Fiorentino D, Lingala B, Krishnan E, Chung L. Atherosclerotic cardiovascular disease and dermatomyositis: an analysis of the Nationwide Inpatient Sample survey. Arthritis Res Ther. 2013 Jan 8. 15(1):R7. [Medline].
Carruthers EC, Choi HK, Sayre EC, Aviña-Zubieta JA. Risk of deep venous thrombosis and pulmonary embolism in individuals with polymyositis and dermatomyositis: a general population-based study. Ann Rheum Dis. 2014 Sep 5. [Medline].
Shimojima Y, Ishii W, Matsuda M, Tazawa K, Ikeda S. Coadministration of tacrolimus with corticosteroid accelerates recovery in refractory patients with polymyositis/ dermatomyositis: a retrospective study. BMC Musculoskelet Disord. 2012 Nov 22. 13:228. [Medline].