The thyrotoxicosis/thrombocytopenia connection.

The association between thrombocytopenia and thyrotoxicosis is well documented in the medical literature. The theories for this relationship include a common immunologic cause and a thyrotoxic-induced decrease in platelet survival. Twenty-two months ago, we performed a subtotal thyroidectomy on a young woman with both disorders who was referred to us for splenectomy with the sole diagnosis of idiopathic thrombocytopenic purpura (ITP). After operation she was weaned from all medications, and she remains euthyroid. Although her platelet count has recently dropped to 80,000/mm3 after a series of upper respiratory infections, she remains free of petechiae and bleeding diathesis. She illustrates two points: thyrotoxicosis should be ruled out in all patients with ITP, and when the two diseases coexist, treatment of the thyrotoxicosis should precede splenectomy. In most instances, this will induce a remission in the ITP that may be permanent.