Association between anti-thyroid peroxidase and anti-cytokeratin 18 autoantibodies and bronchial asthma in women

BackgroundThe mechanisms of intrinsic or non-allergic asthma remain uncertain as allergens have no obvious role in driving the inflammatory process in the airways. This study was designed to test the possible presence of an autoimmune pathogenesis of bronchial asthma and to investigate the similarities and differences between allergic and non-allergic asthma.DesignCross-sectional prospective cohort study.Subjects and methods50 asthmatic women and 30 healthy control women were tested for thyroid function, anti-TPO, anti-CK18 autoantibodies, and total IgE measurements. Pulmonary function tests, skin-prick test and history of asthma risk factors were done for asthmatic women.ResultsAllergic asthma were found in half of the asthmatic patients and the other half (25/50) were non-allergic according to the results of skin-brick test and serum level of IgE. The thyroid function tests were not statistically different between asthmatic and control groups as well as between non-allergic and allergic asthma groups (P > 0.05). Serum anti-TPO autoantibodies and anti-CK18 autoantibodies’ levels were significantly higher in asthmatic patients than the control group and also in non-allergic asthma patients than allergic asthma patients. In asthmatic patients serum anti-TPO autoantibodies showed negative correlation with FEV1 (pre- and post) and serum IgE.ConclusionPositive anti-TPO autoantibodies and anti-CK18 autoantibodies in asthmatic patients and their higher level in the non-allergic asthma group may strengthen the presence of a hidden autoimmune phenomenon in non-allergic asthma.