Nail-fold Capillaroscopic Changes in Children with Juvenile Dermatomyositis and Specific Autoantibodies

Objective: Microvascular changes observed during dermoscopy have been widely used for diagnosing and monitoring various connective tissue disorders, including juvenile dermatomyositis (JDM). This study investigated capillaroscopic changes in nail-folds, specifically, nail-fold capillary density (NFCD), in children with JDM. Methods: A prospective study was conducted on children diagnosed with JDM between 2010 and 2021 who were examined via nail-fold capillaroscopy (n=14) during August and December 2021. Demographic and clinical data, myositis-specific autoantibodies for JDM, and capillaroscopic findings were prospectively collected. In addition to children with JDM (group JDM), we randomly selected 20 children with nonspecific leg pain as the control group. Capillaroscopic findings were compared between the groups. Results: The groups were similar in terms of age and sex characteristics (p=0.848 and p=0.635). Ten children had myositis-specific autoantibodies (71.4%). The median NFCD was significantly lower in the JDM group than in the controls (p=0.001). Children with JDM had a significantly higher frequency and amount of disorganized, tortuous, crossing, enlarged, and giant capillaries than healthy controls (p<0.05). There were significantly higher values of the neoangiogenesis score and MES in Group JDM than in Controls (p<0.001 and p<0.001). Children with positive autoantibodies had higher NFCD and lower interpapillary distance values (p<0.05). Conclusion: Children with JDM exhibited remarkable morphological changes during nail-fold capillaroscopy. Higher neoangiogenesis scores, higher MES values, and decreased NFCD might play a role in diagnosing and differentiating childhood JDM.