Shared Autoimmunity: A Case Series of 56 Patients with Immune Thrombocytopenia (ITP) Associated with Other Autoimmune Disorders
The association of chronic idiopathic thrombocytopenic purpura (cITP) and thyroid autoimmune diseases (TAD) is a known but an uncommon condition. Celiac disease (CD), which is characterized by malabsorption and villous atrophy that occur as a consequence of the ingestion of wheat gluten may also be related to other autoimmune disorders. In this study, we investigated the prevalence of thyroid anti-microsomal (TAMA) and anti-thyroglobulin (TATA) auto antibodies, anti-gliadin (AGA) IgG, IgA, anti-endomisium (EMA) IgG and IgA antibodies in 74 patients with cITP and in 162 healthy controls. TATA positivity was found in 29, and TAMA positivity in 19 out of 74 patients; and in 16 and 18 out of 162 controls respectively (p < 0.0001 and p = 0.005, respectively). TAD was diagnosed in 29 of cITP patients. AGA IgG positivity was found in 17, and IgA was present in five out of 74 patients; and AGA IgG was found in 19, and IgA was detected in 4 out of 162 controls (p = 0.032 and p = 0.143, respectively). EMA IgG positivity was found in six out of 74 patients and in nine out of 162 control subjects (p = 0.566). EMA IgA positivity was found in two out of 74 patients and in one out of 162 controls (p = 0.232). We showed that the prevalence of TAD and related autoantibodies are higher in patients with cITP. We suggest that, patients with cITP should be followed up for development of TAD. In addition, all CD related auto antibodies were found to be more frequent in patients with cITP, but only the AGA IgG reached to the clinical significance. None of the CD related auto antibody positive patients developed clinically manifested CD. Large-scale designed studies are needed to clarify the long-term impact and importance of these CD related auto antibodies in patients with cITP.