RESUMO
BACKGROUND: Alopecia areata (AA) is an autoimmune skin disease characterized by abnormal levels of several cytokines, such as interferon alpha (IFN-α) and tumor necrosis factor-alpha (TNF-α), which are T-helper type 1 cytokines that have important roles in the pathogenesis of AA. The aim of our study was to correlate circulating IFN-α and TNF-α levels with disease severity, activity, and clinical type in patients with AA and to evaluate the relationship between the two cytokines. METHODS: We investigated serum IFN-α and TNF-α levels in 72 patients with AA (35 children and 35 adults) and 75 healthy control individuals (34 children and 41 adults) using the enzyme-linked immunosorbent assay (ELISA) technique. We evaluated AA severity using the Severity of Alopecia Tool (SALT) and determined the activity based on dermoscopic criteria of disease activity. RESULTS: Serum IFN-α and TNF-α concentrations were significantly higher in the patients than in the controls. There was a significant positive correlation between serum IFN-α and TNF-α levels in all patients with alopecia areata, as well as between serum TNF-α levels and disease severity in all patients and in children. CONCLUSIONS: Our results support the association between IFN-α and TNF-α levels and AA and suggest that TNF-α might be related to disease severity.