INTERSTITIAL LUNG-DISEASE WITH AUTOANTIBODIES AGAINST AMINOACYL-TRANSFER-RNA SYNTHETASES IN THE ABSENCE OF CLINICALLY APPARENT MYOSITIS

Autoantibodies against aminoacyl-tRNA synthetases (antisynthetases) ha ve been found to be highly specific for polymyositis and dermatomyosit is and to correlate strongly with complicating interstitial lung disea se (ILD). We describe the clinical presentations and course of 10 pati ents with ILD and anti-synthetase antibodies in whom underlying myosit is was not clinically evident. Anti-PL-12 antibodies (antialanyl-tRNA synthetase) were most common (60%), followed by anti-Jo-1 (antihistidy l-tRNA synthetase) and anti-OJ (anti-isoleucyl-tRNA synthetase) (20% e ach). All 10 patients had anticytoplasmic antibodies by indirect immun ofluorescence on HEp-2 cells. Five of 10 presented with features of co nnective tissue disease, whereas two presented with acute respiratory failure, two with insidious onset of diminished exercise tolerance, an d one with persistent cough. All but one patient received corticostero ids, four were given oral cyclophosphamide, and two azathioprine. ILD resolved or stabilized in five patients (50%), and progressed in four (40%). The ''antisynthetase syndrome'' may occur in the absence of cli nical myositis, and the ILD in these patients is usually responsive to therapy, Antisynthetase testing should be considered in patients with ILD who have a cytoplasmic pattern by antinuclear antibody (ANA) test ing on HEp-2 cells, because early recognition and treatment of such pa tients affects their clinical course. Copyright (C) 1996 by W.B. Saund ers Company