A case of Wong-type dermatomyositis with concomitant anti-MDA5 features
Authors: Theresa Canavan, Tivon Sidorsky, Linda T. Doan, Roberto R. Ricardo-Gonzalez, Guoqiu Shen, Michael D. Rosenblum
Journal: Journal of the American Academy of Dermatology (2014)

To the Editor: Dermatomyositis (DM) is a multisystem autoimmune disease for which multiple phenotypes have been described. Here we report the case of a patient with both Wong-type DM and features of a DM phenotype associated with anti-melanoma differentiation-associated gene 5 antibodies (anti-MDA5 DM). A previously healthy 54-year-old man presented with a 1-year history of a progressive eruption previously diagnosed as pityriasis rubra pilaris (PRP) by 2 independent dermatologists. He had failed topical corticosteroids and 2 courses of oral prednisone pulses, and subsequently weakness and dyspnea on exertion developed. His past medical history was unremarkable. Exam revealed confluent pink-orange patches and plaques over the trunk with islands of sparing (Fig 1), and his extremities displayed hyperkeratotic follicular papules. He also had painful violaceous palmar papules (Fig 2), ragged cuticles, rough radial palms and digits, and subtle violaceous periorbital edema. Proximal muscle strength was 4-5+.Fig 2MDA5 dermatomyositis. Multiple violaceous palmar and digital papules and rough radial palms and digits.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Histology demonstrated superficial perivascular lymphocytes and rare eosinophils below a thin epidermis with vacuolar interface change and necrotic keratinocytes. There was increased mucin in the superficial reticular dermis and hyperkeratosis over follicular infundibulum. A mild elevation of creatine kinase (CK) and inflammatory markers were noted. Results were positive for antinuclear antibodies (speckled pattern) and negative for antibodies to Jo1, SSA, and SSB. Electromyography (EMG) and muscle biopsy were consistent with DM. High-resolution chest computed tomography and an age-appropriate malignancy work-up were unremarkable. Taken together, his mixed DM and PRP-like presentation, histopathology, EMG, muscle biopsy, and CK elevation were consistent with Wong-type DM. His distinct painful palmar papules raised concern for the anti-MDA5 antibody positive DM subtype. Subsequent enzyme-linked immunosorbent assay for anti-MDA5 was positive. He was treated with intravenous methylprednisolone (subsequently transitioned to a slow prednisone taper), intravenous immunoglobulin, mycophenolic mofetil, and hydroxychloroquine. He experienced rapid recovery and demonstrated only minimal cutaneous symptoms and no internal manifestations after 10 months. Wong-type DM is an exceedingly rare DM subtype characterized by PRP-like morphology,1Wong K.O. Dermatomyositis: a clinical investigation of twenty-three cases in Hong Kong.Br J Dermatol. 1969; 81: 544-547Crossref PubMed Scopus (83) Google Scholar which has been described in all 22 prior cases.2Lupton J.R. Figueroa P. Berberian B.J. Sulica V.I. An unusual presentation of dermatomyositis: the type Wong variant revisited.J Am Acad Dermatol. 2000; 43: 908-912Abstract Full Text Full Text PDF PubMed Scopus (37) Google Scholar Histologic findings vary, with features ranging from those typical of DM or PRP alone, to a combination of both (as seen in our patient). Hyperkeratosis overlying follicular infundibulum, as reported here, is common.2Lupton J.R. Figueroa P. Berberian B.J. Sulica V.I. An unusual presentation of dermatomyositis: the type Wong variant revisited.J Am Acad Dermatol. 2000; 43: 908-912Abstract Full Text Full Text PDF PubMed Scopus (37) Google Scholar Similar to typical DM, Wong-type appears to carry a risk for myositis and interstitial lung disease (ILD). Unlike other subtypes, Wong-type DM is not associated with internal malignancy.2Lupton J.R. Figueroa P. Berberian B.J. Sulica V.I. An unusual presentation of dermatomyositis: the type Wong variant revisited.J Am Acad Dermatol. 2000; 43: 908-912Abstract Full Text Full Text PDF PubMed Scopus (37) Google Scholar Our patient's malignancy work-up was negative. Anti-MDA5 DM is a recently described unique DM phenotype with a number of distinct morphologic features, with painful palmar papules and mucocutaneous ulcerations being among the most characteristic.3Fiorentino 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; 65: 25-34Abstract Full Text Full Text PDF PubMed Scopus (425) Google Scholar Incidence ranges from 10% to 20% in Japan to 7% to 13% in the United States.3Fiorentino 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; 65: 25-34Abstract Full Text Full Text PDF PubMed Scopus (425) Google Scholar, 4Sato S. Kuwana M. Fujita T. Suzuki Y. Anti-CADM-140/MDA5 autoantibody titer correlates with disease activity and predicts disease outcome in patients with dermatomyositis and rapidly progressive interstitial lung disease.Mod Rheumatol. 2013; 23: 496-502Crossref PubMed Google Scholar, 5Hall J.C. Casciola-Rosen L. Samedy L.-A. Werner J. Owoyemi K. Danoff S.K. et al.Anti-melanoma differentiation-associated protein 5-associated dermatomyositis: expanding the clinical spectrum.Arthritis Care Res (Hoboken). 2013; 65: 1307-1315Crossref PubMed Scopus (223) Google Scholar Our patient both displayed many anti-MDA5 features, including painful violaceous palmar papules, and had a positive anti-MDA5 ELISA. The most important consequence of anti-MDA5 DM is an increased risk for rapidly progressive ILD and resultant decreased survival, relative to other subtypes.3Fiorentino 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; 65: 25-34Abstract Full Text Full Text PDF PubMed Scopus (425) Google Scholar, 4Sato S. Kuwana M. Fujita T. Suzuki Y. Anti-CADM-140/MDA5 autoantibody titer correlates with disease activity and predicts disease outcome in patients with dermatomyositis and rapidly progressive interstitial lung disease.Mod Rheumatol. 2013; 23: 496-502Crossref PubMed Google Scholar Therefore some recommend early and aggressive treatment in suspected cases of anti-MDA5 DM.4Sato S. Kuwana M. Fujita T. Suzuki Y. Anti-CADM-140/MDA5 autoantibody titer correlates with disease activity and predicts disease outcome in patients with dermatomyositis and rapidly progressive interstitial lung disease.Mod Rheumatol. 2013; 23: 496-502Crossref PubMed Google Scholar Of note, internal malignancy appears to be less common in anti-MDA5 DM. Fortunately, our patient had neither ILD nor malignancy.