Autoimmune thrombocytopenia. Is it a different disease or different aspects of a single disease?

OBJECTIVE To evaluate the association between autoimmune thrombocytopenia with other autoimmune disorders, to show if they are different autoimmune diseases or one disease with different presentations at the same time, and to study the effect of treatment on platelet count in different thyroid condition. METHODS In this retrospective study, we included 141 patients with thrombocytopenic purpura. The result of thyroid function test, thyroid autoantibodies, Coombs' reactivity, anti-nuclear antibody, and double-stranded DNA were analyzed. This study was conducted in the Clinical Hematology Department, King Abdulaziz University Hospital, Jeddah, Saudi Arabia between June 2003 and August 2010. RESULTS There were 51 (36.2%) patients with laboratory evidence of autoimmune disease, 13 (9.2%) with hypothyroidism, and 6 (4.3%) with hyperthyroidism. In addition, 5 (3.5%) patients showed laboratory evidence of Evan syndrome and 3 (2.1%) patients had isolated positive thyroid antibodies. There was non-significant difference (p=0.61) in platelets count after one month of treatment of patients with different thyroid condition. CONCLUSION Immune thrombocytopenia is associated with evidence of different autoimmune disease or a combination of them, which may appear at presentation or during the course of disease giving evidence that they are different manifestations of a single disease. Screening patients for antithyroid antibodies would identify a patient at risk of developing overt thyroid disease. These patients may be further screened with a thyroid-stimulating hormone assay to detect subclinical thyroid disease.