Autoimmune disorders in patients with idiopathic thrombotic thrombocytopenic purpura

76 German patients suffering from thrombotic thrombocytopenic purpura (TTP) were interrogated about the prevalence of co-occurring autoimmune disorders. In order to analyze a possible association of TTP with the questioned diseases, a comparison of prevalence rates between the patient group and the general population has been made for each disease.

Compared to the estimated prevalence rates, the statistical analysis revealed an unexpected high occurrence of the following disorders within the patient group: Hashimoto's thyroiditis (23.5% within the patients compared to 0.7% within the general population, p<0.001), systemic lupus erythematosus (SLE) (6.5% in patients to 0.025% in the general population, p<0.001), immune thrombocytopenic purpura (ITP) (6.3% in patients to 0.02% in the general population, p<0.001), psoriasis (9.4% in patients to 2.5% in the general population, p=0.005) and celiac disease (3.1% in patients to 0.2% in the general population, p=0.007).

These findings confirm the mentioned tendency of autoimmune diseases to co-occur in one individual and argue once more for a genetic susceptibility in idiopathic TTP as well as in autoimmune disorders.