The comparison of nailfold videocapillaroscopy findings between anti-melanoma differentiation-associated gene 5 antibody and anti-aminoacyl tRNA synthetase antibody in patients with dermatomyositis complicated by interstitial lung disease

Dermatomyositis (DM) is frequently complicated by interstitial lung disease (ILD), which increases mortality. This study aims to elucidate the clinical significance of nailfold videocapillaroscopy (NVC) on assessing the disease activity and prognosis of DM-ILD. We compared the NVC findings between anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive and anti-aminoacyl tRNA synthetase (anti-ARS) antibody-positive patients, the survival and ILD-related death groups, and examined the association of NVC findings with prognostic factors of DM-ILD. The median scores of microhemorrhage and capillary disorganization in the anti-MDA5 antibody-positive group were significantly higher than those in the anti-ARS antibody-positive group (P = 0.012 and 0.044, respectively). In contrast, the median scores of tortuous capillaries in the anti-ARS antibody-positive group were significantly higher than those in the anti-MDA5 antibody-positive group (P = 0.002). The median scores of microhemorrhage was significantly higher in the ILD-related death group than the survival group (P = 0.02). The scores of microhemorrhage, capillary disorganization, and neoangiogenesis correlated with known poor prognosis factors of DM-ILD. Additionally, the scores of microhemorrhage and capillary loss correlated significantly with the total fibrosis scores of chest high-resolution computed tomography. These findings suggest that NVC is a useful tool for assessing the disease activity and prognosis of DM-ILD.