title: Anti-MDA5 antibody, ferritin and IL-18 are useful for the evaluation of response to treatment in interstitial lung disease with anti-MDA5 antibody-positive dermatomyositis.
abstract: OBJECTIVE
  The aim of this study was to investigate the precise clinical characteristics and to analyse the association between the anti-MDA5 antibody (anti-MDA5ab) titre and disease status in patients with anti-MDA5ab-positive DM.
  
  
  METHODS
  Twenty-seven patients who presented with DM and were positive for the anti-MDA5ab were enrolled. The association between the clinical manifestations and the clinical parameters, including the anti-MDA5ab, was analysed.
  
  
  RESULTS
  The complication of rapidly progressive interstitial lung disease (RP-ILD) occurred in 20 (74%) patients. The frequencies of fatal outcome, relapse and malignancy were 33, 4 and 4%, respectively. Remarkably, a fatal outcome occurred within the first 6 months. Compared with six non-RP-ILD patients, elderly age at onset, severely involved pulmonary function and high levels of serum ferritin were present in 20 RP-ILD patients with anti-MDA5ab. Alveolar-arterial oxygen difference (AaDO(2)) ≥32 mmHg and ferritin ≥828 ng/ml at admission were poor prognostic factors in RP-ILD patients with anti-MDA5ab-positive DM. The median value of the anti-MDA5ab titre on admission was higher in patients who later died than in those who survived. The efficacy of treatment was indicated by the anti-MDA5ab, ferritin and IL-18 concentrations. The decline index of the anti-MDA5ab titre after treatment was lower in the subset of patients who died than in the subset of patients who lived. Sustained high levels of anti-MDA5ab, ferritin and IL-18 were present in the patients who died.
  
  
  CONCLUSIONS
  Anti-MDA5ab titre and ferritin and IL-18 concentrations are useful for the evaluation of the response to treatment and the status of ILD in patients with anti-MAD5ab-positive DM.
authors.affiliation: Institute of Rheumatology, Tokyo Women's Medical University, 10-22 Kawada-cho, Shinjuku-Ku, Tokyo, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Gono
authors.forename: Shinji
authors.initials: S
authors.lastname: Sato
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kawaguchi
authors.forename: Masataka
authors.initials: M
authors.lastname: Kuwana
authors.forename: Masanori
authors.initials: M
authors.lastname: Hanaoka
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Katsumata
authors.forename: Kae
authors.initials: K
authors.lastname: Takagi
authors.forename: Sayumi
authors.initials: S
authors.lastname: Baba
authors.forename: Yuko
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ota
authors.forename: Hisashi
authors.initials: H
authors.lastname: Yamanaka
mesh_terms: D001323:Autoantibodies / Q000097:blood*; D065095:Calcineurin Inhibitors; D016572:Cyclosporine / Q000627:therapeutic use; D053487:DEAD-box RNA Helicases / Q000276:immunology*; D003882:Dermatomyositis / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality; D004359:Drug Therapy, Combination; D005260:Female; D005293:Ferritins / Q000097:blood*; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D000072640:Interferon-Induced Helicase, IFIH1; D020382:Interleukin-18 / Q000097:blood*; D007564:Japan / Q000453:epidemiology; D017563:Lung Diseases, Interstitial / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011239:Prednisolone / Q000627:therapeutic use; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D001323:Autoantibodies; D065095:Calcineurin Inhibitors; D005938:Glucocorticoids; D020382:Interleukin-18; D016572:Cyclosporine; D005293:Ferritins; D011239:Prednisolone; C452815:IFIH1 protein, human; D053487:DEAD-box RNA Helicases; D000072640:Interferon-Induced Helicase, IFIH1