Kiminobu Tanizawa1, Tomohiro Handa2, Ran Nakashima3, Takeshi Kubo4, Yuji Hosono3, Kizuku Watanabe5, Kensaku Aihara6, Kohei Ikezoe7, Akihiko Sokai7, Yoshinari Nakatsuka7, Yoshio Taguchi8, Kazuhiro Hatta9, Satoshi Noma10, Yoichiro Kobashi11, Akihiko Yoshizawa12, Toru Oga1, Toyohiro Hirai7, Kazuo Chin1, Sonoko Nagai13, Takateru Izumi12, Tsuneyo Mimori3, Michiaki Mishima7. 1. Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan. 2. Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Electronic address: hanta@kuhp.kyoto-u.ac.jp. 3. Department of Rheumatology and Clinical Immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan. 4. Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan. 5. Department of Respiratory Medicine, Fukui Red-Cross Hospital, Fukui, Japan. 6. Department of Respiratory Medicine, Saiseikai Noe Hospital, Osaka, Japan. 7. Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan. 8. Department of Respiratory Medicine, Tenri Hospital, Tenri, Japan. 9. Department of Rheumatology, Tenri Hospital, Tenri, Japan. 10. Department of Radiology, Tenri Hospital, Tenri, Japan. 11. Department of Pathology, Tenri Hospital, Tenri, Japan. 12. Department of Diagnostic Pathology, Kyoto University Hospital, Kyoto, Japan. 13. Kyoto Central Clinic, Clinical Research Center, Kyoto, Japan.
Abstract
RATIONALE: Anti-aminoacyl transfer RNA synthetase antibodies (anti-ARS) are a group of myositis-specific autoantibodies that are detected in the sera of patients with polymyositis and dermatomyositis (PM/DM) and also in those of patients with idiopathic interstitial pneumonias without any connective tissue disease (CTD), including PM/DM. Although we reported the clinical characteristics of interstitial lung disease with anti-ARS antibodies (ARS-ILD) with and without PM/DM, the long-term prognosis of ARS-ILD remains undetermined. As our previous studies revealed that ARS-ILD without PM/DM was similar to CTD-associated ILD, and that ARS-ILD with PM/DM was radiologically suggestive of a nonspecific interstitial pneumonia (NSIP) pathological pattern, we hypothesized that the prognosis of ARS-ILD might be distinct from that of idiopathic pulmonary fibrosis (IPF) without anti-ARS. OBJECTIVES: To elucidate the long-term outcome of ARS-ILD with and without PM/DM and compare it to that of IPF. METHODS: A two-center retrospective study was conducted. The study population comprised 36 patients with ARS-ILD (8 with PM, 12 with DM, and 16 without myositis throughout the course), 100 patients with IPF without anti-ARS, and 7 patients with NSIP without anti-ARS. The presence of anti-ARS was determined by RNA immunoprecipitation using the sera obtained at the time of diagnosis before specific treatment. MEASUREMENTS AND MAIN RESULTS: During the observational period (median 49 months; range, 1-114 months), 7 patients with ARS-ILD (19%; 3 with PM, 1 with DM, and 3 without PM/DM) and 51 patients with IPF (51%) died. Patients with ARS-ILD had better overall survival than those with IPF (log-rank test, P < 0.001) and similar survival compared to those with NSIP (log-rank test, P = 0.59). The prognosis for patients with ARS-ILD was similar between those with and without myositis (log-rank test, P = 0.91). At the median follow-up time of 76.5 months, 14 of the 36 patients with ARS-ILD had deteriorated. Both a decline in forced vital capacity or an initiation of long-term oxygen therapy during the course (odds ratio [OR], 5.34) and acute exacerbation (OR, 28.4) significantly increased the mortality risk. CONCLUSIONS: The long-term outcome of ARS-ILD was significantly better than that of IPF regardless of the presence or absence of myositis.
RATIONALE: Anti-aminoacyl transfer RNA synthetase antibodies (anti-ARS) are a group of myositis-specific autoantibodies that are detected in the sera of patients with polymyositis and dermatomyositis (PM/DM) and also in those of patients with idiopathic interstitial pneumonias without any connective tissue disease (CTD), including PM/DM. Although we reported the clinical characteristics of interstitial lung disease with anti-ARS antibodies (ARS-ILD) with and without PM/DM, the long-term prognosis of ARS-ILD remains undetermined. As our previous studies revealed that ARS-ILD without PM/DM was similar to CTD-associated ILD, and that ARS-ILD with PM/DM was radiologically suggestive of a nonspecific interstitial pneumonia (NSIP) pathological pattern, we hypothesized that the prognosis of ARS-ILD might be distinct from that of idiopathic pulmonary fibrosis (IPF) without anti-ARS. OBJECTIVES: To elucidate the long-term outcome of ARS-ILD with and without PM/DM and compare it to that of IPF. METHODS: A two-center retrospective study was conducted. The study population comprised 36 patients with ARS-ILD (8 with PM, 12 with DM, and 16 without myositis throughout the course), 100 patients with IPF without anti-ARS, and 7 patients with NSIP without anti-ARS. The presence of anti-ARS was determined by RNA immunoprecipitation using the sera obtained at the time of diagnosis before specific treatment. MEASUREMENTS AND MAIN RESULTS: During the observational period (median 49 months; range, 1-114 months), 7 patients with ARS-ILD (19%; 3 with PM, 1 with DM, and 3 without PM/DM) and 51 patients with IPF (51%) died. Patients with ARS-ILD had better overall survival than those with IPF (log-rank test, P < 0.001) and similar survival compared to those with NSIP (log-rank test, P = 0.59). The prognosis for patients with ARS-ILD was similar between those with and without myositis (log-rank test, P = 0.91). At the median follow-up time of 76.5 months, 14 of the 36 patients with ARS-ILD had deteriorated. Both a decline in forced vital capacity or an initiation of long-term oxygen therapy during the course (odds ratio [OR], 5.34) and acute exacerbation (OR, 28.4) significantly increased the mortality risk. CONCLUSIONS: The long-term outcome of ARS-ILD was significantly better than that of IPF regardless of the presence or absence of myositis.