JRD Journal of Rheumatic Diseases J Rheum Dis 2093-940X 2233-4718 The Korean College of Rheumatology 10.4078/jrd.2017.24.4.241 jrd-24-241 Case Report A Case of Polymyositis Associated with Immunoglobulin A Nephropathy OhYoon-Jeong 1 ParkEun Sung 1 JangMi 2 KangEa Wha 3 KieJeong-Hae 4 LeeSang-Won 1 SongJason Jungsik 1 ParkYong-Beom 1 LeeChan-Hee 5 ParkJin-Su 5 Division of Rheumatology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea Department of Pathology, Yonsei University College of Medicine, Seoul, Korea Division of Nephrology, Department of Internal Medicine, National Health Insurance Service Ilsan Hospital, Goyang, Korea Department of Pathology, National Health Insurance Service Ilsan Hospital, Goyang, Korea Division of Rheumatology, Department of Internal Medicine, National Health Insurance Service Ilsan Hospital, Goyang, Korea Corresponding to: Jin-Su Park, Division of Rheumatology, Department of Internal Medicine, National Health Insurance Service Ilsan Hospital, 100, Ilsan-ro, Ilsandong-gu, Goyang 10444, Korea. E-mail: jinsulog@naver.com 10 2017 31 10 2017 24 4 241 245 03102016 02012017 16032017 Copyright © 2017 The Korean College of Rheumatology 2017 This is a Open Access article, which permits unrestricted non-commerical use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract

Polymyositis (PM) is a chronic inflammatory disease that predominantly affects muscles. Systemic organ involvement, including the respiratory and gastrointestinal tracts, is frequently observed in PM, but renal involvement is rare. Herein, we report the case of a 56-year-old woman presenting with weight gain, edema, and generalized myalgia. Laboratory tests revealed elevated creatinine kinase level, hypoalbuminemia, and proteinuria. Histopathological examination of muscle biopsy revealed inflammatory myositis, and a renal biopsy confirmed immunoglobulin A (IgA) nephropathy. Based on the clinicopathological results, the patient was diagnosed with PM with IgA nephropathy. This is a report of a rare occurrence of IgA nephropathy in a patient with PM presenting with chronic glomerulonephritis.

 Polymyositis IgA nephropathy Proteinuria REFERENCES Bohan A Peter JB Polymyositis and dermatomyositis (first of two parts) N Engl J Med 1975 292 3447 Takizawa Y Kanda H Sato K Kawahata K Yamaguchi A Uozaki H Polymyositis associated with focal mesangial proliferative glomerulonephritis with depositions of immune complexes Clin Rheumatol 2007 26 7926 Cucchiari D Angelini C Renal involvement in idiopathic inflammatory myopathies Clin Rev Allergy Immunol 2017 52 99107 Wu Y Chhaya S Hurowitz B Ardiles T Carlson R Clinically amyopathic dermatomyositis complicated by pleural effusion case report, literature review, and proposed mechanism Bull Hosp Jt Dis (2013) 2015 73 21720 Qian Y Ren H Zhang W Chen N Clinical features of polymyositis and dermatomyositis in four patients with renal involvement as mainly presentation Zhonghua Nei Ke Za Zhi 2009 48 9302 Nickavar A Mehr Azma M Nephrotic syndrome and juvenile dermatomyositis Rheumatol Int 2012 32 29335 Findlay AR Goyal NA Mozaffar T An overview of polymyositis and dermatomyositis Muscle Nerve 2015 51 63856 Couvrat-Desvergnes G Masseau A Benveniste O Bruel A Hervier B Mussini JM The spectrum of renal involvement in patients with inflammatory myopathies Medicine (Baltimore) 2014 93 3341 Shin DH Lim BJ Han IM Han SG Kwon YE Park KS Glomerular IgG deposition predicts renal outcome in patients with IgA nephropathy Mod Pathol 2016 29 74352 Civilibal M Selcuk Duru N Ozagari A Durali K Elevli M Immunoglobulin A nephropathy associated with juvenile dermatomyositis Pediatr Nephrol 2009 24 20735 Pouria S Barratt J Secondary IgA nephropathy Semin Nephrol 2008 28 2737 Stertz G Polymyositis Berl Klin Wochenschr 1916 53 489 Levine SM Cancer and myositis: new insights into an old association Curr Opin Rheumatol 2006 18 6204 Barros TB de Souza FH Malheiros DM Levy-Neto M Shinjo SK IgA nephropathy and polymyositis: a rare association Rev Bras Reumatol 2014 54 2313 Figures

Muscle biopsy. (A) Light microgram of a muscle biopsy specimen (H&E, ×40). (B) Light microgram showing inflammatory cell infiltrates (black arrows) scattered throughout the endomysium, invading individual muscle fibers (H&E, ×200).(C) On immunohistochemistry, the inflammatory cells express leukocyte common antigen (black arrows) (Immunohistochemistry,×200). (D) Anti CD 68 staining of the muscle biopsy specimen (Immunohistochemistry, ×200).

Renal biopsy. (A) Light microgram showing mild mesangial expansion (black arrows) without cellular proliferation (Periodic acid Schiff, ×400). (B) Some glomeruli showed segmental sclerotic change and synechia with Bowman's capsule (PAS-silver stain, ×400). (C) Immunofluorescence staining revealed moderate positivity for IgA on the mesangium and para-mesangium (Immunofluorescence staining, ×400). (D) Electron microgram demonstrating deposits in the mesangium and para-mesangium (Uranyl acetate, ×6,000).