Polymyositis/dermatomyositis-associated lung disease: analysis of a series of 81 patients

Abstract

The objective of this study was to assess the prevalence, clinical, histological and immunological characteristics, and the long-term outcome of polymyositis- (PM) and dermatomyositis- (DM) associated lung disease, and to define subgroups of lung-associated inflammatory myopathies. This retrospective study included 81 consecutive patients diagnosed with PM/DM. Pulmonary involvement was systematically investigated in relation to clinical symptoms by chest radiography, high resolution computed tomography and pulmonary function testing. Anti-synthetase autoantibodies (ASA) were analysed by ELISA and confirmed by protein and RNA immunoprecipitation methods. Statistical analyses were done with the Student t-test and Fisher exact test. Cumulative survival probabilities were estimated by the Kaplan-Meier method and Cox regression analysis. Fifty patients (61%) presented pulmonary involvement. Thirty-two (39%) had interstitial lung disease and five of them had devastating acute interstitial pneumonia with pneumomediastinum and an unfavorable prognosis. Histology showed diffuse alveolar damage in this subgroup and ASA were negative. Eighteen patients (22%) presented restrictive myopathic lung disease; in three of them respiratory muscles could not maintain ventilation. ASA were positive in 17 of the 50 patients (34%) and were significantly associated with interstitial lung disease (OR: 4.5 [95% CI: 1.3-15.3]), arthritis (OR: 6.0 [95% CI: 1.3-29.2]) and 'mechanic hands' (OR: 8.5 [95% CI: 1.7-41.4]); the presence of these autoantibodies did not imply worse survival prognosis. We concluded that clinical and immunological characteristics allowed the grouping of patients into different types of PM/DM lung-associated disease. Presence of ASA did not affect survival. ASA-negative patients with acute interstitial pneumonitis and pneumomediastinum had an unfavorable prognosis.

Idiopathic inflammatory myopathies and the lung

“…Interstitial lung disease Epidemiology ILD is a frequent manifestation of dermatomyositis/polymyositis with the prevalence of clinically relevant ILD ranging from 17% to 36% [9,[47][48][49][50][51]. In a prospective series of patients with systematic assessment of lung involvement, the prevalence was estimated to be 65% [9].…”

“…Up to half of patients with IIM-associated ILD may eventually die from respiratory failure [13]. The mortality rate is especially high in acute forms of ILD despite immediate and aggressive treatment [48,58].…”

Interstitial lung disease: are we missingformes frustesof connective tissue disease?

“…Acute respiratory deteriorations of ILD have occasionally been reported in patients with idiopathic inflammatory myopathy [11,19,37], as well as rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis [2,38], and are usually associated with a poor prognosis. Acute/subacute forms of CTD-associated ILD share the features of acute exacerbations of IPF, a condition also characterised by recent onset of increased dyspnoea, diffuse bilateral ground-glass opacities superimposed on subpleural reticular and honeycombing densities, and worsening gas exchange, in the absence of an identifiable cause other than the pre-existing ILD.…”

Interstitial Lung Disease Associated with Clinically Amyopathic Dermatomyositis

“…Each of these antibodies has been associated with antisynthetase syndrome marked by a high frequency of intestitial lung disease compared with PM-DM without such antibodies (Targoff, 2008). Selva-O'Callaghan et al reported that anti-aaRS negative patients with acute interstitial lung disease and pneumomediastinum had an unfavorable prognosis (Selva-O'Callaghan et al, 2005).…”

“…It is increasingly recognized as a serious complication and a major cause of death in this disease (Douglas et al, 2001, Fathi et al, 2008, Marie et al, 2002. High-resolution computerized tomography in combination with pulmonary function tests provides sensitive tools to detect early signs of intestitial lung disease (Selva-O'Callaghan et al, 2005). The clinical presentation of interstitial lung disease includes progressive dyspnea on exertion, nonproductive cough, and basilar rales, and a rapidly progressive syndrome (HammanRich) may also occur.…”