Clinical evaluation of anti-aminoacyl tRNA synthetase antibodies in Japanese patients with dermatomyositis.
OBJECTIVE
To investigate the distribution of anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies among patients with autoimmune diseases, and to analyze the clinical features of patients with dermatomyositis (DM) with anti-ARS antibodies.


METHODS
Serum samples from 315 patients with autoimmune diseases or related disorders who had visited Kanazawa University Hospital or affiliated facilities were assessed for anti-ARS antibodies by immunoprecipitation. In particular, the association between anti-ARS antibodies and clinical features was investigated in detail in patients with DM.


RESULTS
Anti-ARS antibody was positive in 16 (29%) of 55 patients with DM, 2 (22%) of 9 patients with polymyositis, and 7 (25%) of 28 patients with idiopathic pulmonary fibrosis. Although anti-ARS antibody was detected with high frequency (63%, 15/24) in DM patients with interstitital lung disease (ILD), the incidence of anti-ARS antibody was very low (3%, 1/31) in DM patients without ILD. Anti-ARS antibody-positive patients with DM had significantly higher incidences of ILD (94% vs 23%) and fever (64% vs 10%) than the antibody-negative patients. Some immunosuppressive agents, in addition to oral corticosteroids, were required more frequently in the antibody-positive patients with DM than the antibody-negative patients (88% vs 26%). Although 60% of DM patients with ILD simultaneously developed ILD and myositis, ILD preceded myositis in 33% of patients.


CONCLUSIONS
Among patients with DM, anti-ARS antibodies are found in a subset with ILD. DM patients with anti-ARS antibodies appear to have a more persistent disease course that requires additional therapy compared to those without anti-ARS antibodies.
Matsushita
Takashi
T
Department of Dermatology and Division of Respiratory Medicine, Cellular Transplantation Biology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
Hasegawa
Minoru
M
Fujimoto
Manabu
M
Hamaguchi
Yasuhito
Y
Komura
Kazuhiro
K
Hirano
Takashi
T
Horikawa
Mayuka
M
Kondo
Miki
M
Orito
Hidemitsu
H
Kaji
Kenzo
K
Saito
Yuki
Y
Matsushita
Yukiyo
Y
Kawara
Shigeru
S
Yasui
Masahide
M
Seishima
Mariko
M
Ozaki
Shoichi
S
Kuwana
Masataka
M
Ogawa
Fumihide
F
Sato
Shinichi
S
Takehara
Kazuhiko
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000604:Amino Acyl-tRNA Synthetases / Q000276:immunology*; D044466:Asian People; D001323:Autoantibodies / Q000097:blood*; D001327:Autoimmune Diseases / Q000150:complications / Q000276:immunology / Q000473:pathology; D003882:Dermatomyositis / Q000150:complications / Q000276:immunology / Q000473:pathology*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006785:Hospitals, University; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012129:Respiratory Function Tests
D001323:Autoantibodies; D000604:Amino Acyl-tRNA Synthetases