Intralesional methotrexate in patchy alopecia areata: trichoscopic evaluation and effect on lesional tumour necrosis factor alpha

Introduction Alopecia areata (AA) is an autoimmune disease characterized by T-cell infiltrates and cytokine production, including tumor necrosis factor alpha (TNF-α). Methotrexate (MTX) causes T-cell apoptosis and adenosine release, among multiple anti-inflammatory actions, inhibits white blood cell accumulation, leads to a reduction in TNF-α and interferon gamma synthesis, and inhibits a variety of monocyte and T-cell activities. Therefore, it is hypothesized that MTX could be valuable in the treatment of AA. Objective To assess the efficacy of intralesional (IL) MTX in the treatment of patchy AA and study its effect on TNF-α tissue levels. Patients and methods This prospective interventional study included 15 patients with patchy AA who received IL-MTX every 2 weeks for 3 months, and a scalp biopsy was taken before and after treatment to measure lesional TNF-α level. Results On comparing the severity alopecia tool score of patients before and 6 months after IL-MTX, there was a statistically significant reduction in severity alopecia tool score ( P <0.001) associated with highly significant reduction in lesional TNF-α level with total percentage of improvement 50%. Six months after IL-MTX, 46.7% of participants showed excellent response, 53.3% showed good response, and no patients showed poor response. There was a highly significant decrease in exclamation mark hairs, black dots, broken hairs, and yellow dots. In addition, vellus hairs, and terminal hairs showed a high statistically significant increase after IL-MTX. Conclusion IL-MTX is effective in patchy AA with a possible mechanism of action through decreasing TNF-α tissue level.