Nailfold capillaroscopy findings in cutaneous lupus erythematosus patients with or without digital lesions and comparison with dermatomyositis patients: A prospective study.

Background: Differential diagnosis between cutaneous lupus erythematosus (CLE) and dermatomyositis (DM) may be challenging if digital lesions occur. Objectives: To compare nailfold capillaroscopy (NFC) findings in CLE patients with or without digital involvement, and to compare capillaroscopic findings between CLE patients with digital lesions and DM patients. Methods: Prospective monocentric study including CLE and DM patients. NFC was performed and standardized items were recorded. Results: Fifty-one CLE patients and 10 DM patients with digital lesions were included. A scleroderma pattern was found in 6 patients (12%): in 5 out of 17 patients with digital lesions, compared with only 1 out of 34 patients without digital lesions (p = 0.01). In multivariate analysis, CLE digital lesions and digital ulcerations were statistically associated with scleroderma pattern. CLE digital lesions were significantly associated with architectural disorganization (p = 0.0003) and capillary rarefaction (p = 0.0038). A scleroderma pattern was significantly more frequent in DM patients (80%) than in CLE patients with digital lesions (30%, p = 0.018). Capillaroscopic findings were not significantly different between CLE patients with digital lesions and DM patients. Conclusion: Although scleroderma pattern is more frequent in DM patients than in CLE patients with digital lesions, NFC cannot formally distinguish CLE from DM. [ABSTRACT FROM AUTHOR]