Objective To analyze the clinical features of,concurrence of allergic diseases in,as well as serum levels of total immunoglobulin E (IgE) and specific IgEs in,232 patients with alopecia areata (AA),and to estimate their relationship.Methods Serum samples were obtained from 232 patients with AA and 110 healthy controls from a health check-up center.Turbidimetric immunoassay and fluorescence-based enzyme-linked immunosorbent assay were performed to measure total IgE and specific IgEs to common antigens in these serum samples,respectively.Statistical analysis was carried out by t test,rank sum test,and chi-square test.Results The patients showed a male/female ratio of 127 ∶ 105 with an average age of (26.4 ± 13.8) years and clinical course of (25.3 ± 42.3) months.Among these patients,89 (38.4％) suffered from severe AA,and 67 (28.9％) reported at least one allergic disease.No significant difference was found in the positive rates of serum total IgE (30.2％ vs.21.8％,P ＞ 0.05),anti-Dermatophagoides pteronyssinus and-Cockroach specific IgEs or the serum levels of antiDermatophagoides pteronyssinus or-Cockroach IgE between the patients and healthy controls.The three most common specific IgEs were anti-Dermatophagoides pteronyssinus IgE (34.1％),anti-Dermatophagoides farinae IgE (31.9％) and anti-Cockroach IgE (22.5％) in patients with AA,whose serum levels were positively correlated with the level of serum total IgE separately.A significant increase was observed in the positive rates and serum levels of anti-Dermatophagoides pteronyssinus and-Cockroach specific IgEs in patients with severe and diffuse AA compared with the healthy controls and patients with mild AA,as well as in those of anti-Dermatophagoides pteronyssinus specific IgE in child patients with AA compared with the healthy controls and adult patients with AA (P ＜ 0.05 or 0.01).Conclusions Dust mite allergy may be not only a pathogenic factor for severe,diffuse and childhood AA,but also a risk factor for early onset and severe type of AA.