Background Discoid lupus erythematosus (DLE) is one of the LE-specific skin diseases on the scalp, and some cases induce scarring alopecia. In systemic LE (SLE), variable nail changes not specific to LE can occur, including leukonychia, longitudinal ridges, and partial onycholysis. However, there are insufficient reports that investigate the characteristics and relationship of hair and nail changes in LE patients.

Methods This was a retrospective study that included 113 CLE patients who visited the Department of Dermatology at Hanyang University Seoul Hospital in Korea between October 2021 and October 2022. Patient medical records, demographic information, and clinical photographs were reviewed, and all patients were examined for scalp and fingernail involvement, Raynaud phenomenon, and laboratory findings.

Results Among the 113 CLE patients, 69 (61.1%) showed hair loss and 19 (16.8%) showed fingernail involvement. The CLE patients with hair loss exhibited earlier disease onset (p=0.001) and were more frequently accompanied by SLE (p<0.001), facial CLE lesions (p=0.012), and fingernail changes (p=0.012). Of the 69 CLE patients with hair loss, 59 (85.5%) showed DLE alopecia. In the DLE alopecia group, patients with fingernail changes showed a higher incidence rate of additional CLE lesions on extremities (p=0.049) and the Raynaud phenomenon than those without fingernail changes (p=0.009). There were significant differences in positivity for antinuclear antibody between CLE patients with DLE alopecia and other patients (p=0.04).

Conclusions This study reviewed the clinical features of scalp and nail apparatus involvement in Korean CLE patients and is the first study to demonstrate significant correlations between these clinical findings and the laboratory findings. Involvement of the scalp and nails in CLE patients is an important disease manifestation, and proper understanding could be essential for diagnosis and efficient management.