Non-scarring alopecia in systemic lupus erythematosus patients at the Lagos State University Teaching Hospital: a cross-sectional study of prevalence, pattern, trichoscopy features and histopathological analysis.

INTRODUCTION: trichoscopic and histopathological evaluation of non-scarring systemic lupus erythematosus (SLE) alopecia is uncommon. We aimed to document the prevalence, pattern of hair loss, trichoscopic and histopathologic differences between systemic lupus erythematosus patients with and without hair loss.

METHODS: this was a cross-sectional comparative study of 75 systemic lupus erythematosus patients, 36 with hair loss from February to December 2020. Trichoscopic evaluation was conducted on all 75 patients. Twenty-three patients (12 with hair loss and 11 without) had scalp biopsies with mucin deposit evaluation. Disease activity was documented using the SLE disease activity index. Data was analyzed using SPSS 22.

RESULTS: the mean age of the patients was 33.7 ± 12.4 years. Non-scarring alopecia was observed in 48%. The pattern of hair loss was <4 patches in 44.4%, mild diffuse in 25%, and severe diffuse in 30.6%. Disease activity was mild in 38.9%. Hair shaft changes included thin hair (97.2%), decreased number of hairs per follicular unit (97.2%), hypopigmented hair (85.7%), and follicular red dots (27.8%). Significant differences between the two groups were; a reduction in size and number of sebaceous glands on histopathology, hair shaft, and scalp pigmentary changes in the hair loss group.

CONCLUSION: the prevalence of non-scaring alopecia is high in SLE patients with patchy type as the commonest pattern. Trichoscopic and histopathologic differences exist in SLE patients with and without hair loss and the normal-appearing scalp in SLE patients is involved in the inflammatory process. Hair shaft thinning, hypopigmentation, and scalp pigmentary changes occur in SLE.