Lung involvement associated with anti-NXP2 autoantibodies in inflammatory myopathies: a French monocenter series.

ABSTRACT

BACKGROUND: Inflammatory myopathies (IM) are characterized by muscular inflammation that can be associated with systemic disorders including lung. Anti-NXP2 antibody (Ab) is a rare myositis-specific antibody and its association with pulmonary involvement is still unknown. In this study, we investigated the characteristics of lung disease in patients with IM associated with anti-NXP2 Ab. METHODS: Adult patients with confirmed IM and positive anti-NXP2 antibodies were recruited in our University departments (Assistance Publique- Hôpitaux de Marseille, France), between 2015 and 2019 to perform a retrospective study. RESULTS: Seven patients were identified. Mean age was 55 ± 13 years, with a predominance of females (71%). Two patients (29%) had respiratory symptoms. CT-scan shows abnormalities in three patients (organizing pneumonia, nonspecific interstitial pneumonia, and bilateral pleural effusion). An altered diffusing capacity for carbon monoxide was found in four patients. CONCLUSION: We observed that subclinical lung involvement is not rare in patients with IM associated with positive anti-NXP2 Ab, with various radiological patterns and a significant lung function defect. Such data deserve to be known by the pulmonologist in order to perform a complete lung screening in all patients with positive anti-NXP2 antibody and to detect earlier a concomitant lung impairment.