Four patients with both thrombotic thrombocytopenic purpura and autoimmune thrombocytopenic purpura: The concept of a mixed immune thrombocytopenia syndrome and indications for plasma exchange

Abstract

Autoimmune thrombocytopenic purpura (ATP) and thrombotic thrombocytopenic purpura (TTP) are each well recognized clinical syndromes which may appear as single episodes or may have chronic relapsing courses. We present four patients negative for human immunodeficiency virus (HIV) infection who appear to have both diagnoses with either concomitant or intermingled episodes, and we review seven additional patients reported in the literature with similar features. All four of our patients are female, two have underlying connective tissue disorders, and their ATP processes came to our attention because of incomplete response of the platelet count to plasma exchange therapy (PEX) during a TTP phase (Cases 1 and 2) or development of thrombocytopenia in the absence of microangiopathy on the background of prior typical TTP episodes (Cases 3 and 4). Recognition of the ATP diagnosis in each case resulted in discontinuation of PEX (Cases 1 and 2) or not instituting PEX (Cases 3 and 4). In each instance, a satisfactory rise in platelet count followed treatment for ATP. Based upon this experience, we conclude that some individuals may have a mixed immune thrombocytopenia syndrome; careful analysis of the mechanism of thrombocytopenia, especially in recurrent episodes and in patients who respond incompletely to PEX for TTP, is important when deciding whether to initiate or continue PEX, or to consider therapies appropriate for other mechanisms of thrombocytopenia.

First two patients with ulcerative colitis who developed classical thrombotic thrombocytopenic purpura successfully treated with medical therapy and plasma exchange

“…However, testing for such antibodies is not yet readily clinically available. We recently reported four patients in whom TTP was associated with ITP and cited from the medical literature other well recognized autoimmune disorders associated with TTP, e.g., autoimmune hemolytic anemia [7]. In this context, the two patients that we here report with UC and clinical features of TTP, together with a third case in the literature, suggest that acquired TTP may be yet another extraintestinal autoimmune feature of IBD.…”

New‐onset and idiopathic thrombotic thrombocytopenic purpura: Incidence, diagnostic validity, and potential risk factors

“…We also identified two patients (Cases 1 and 12) who had a chronic history of thrombocytopenia or ITP. An association between ITP and TTP, either as concomitant disease or as sequential processes, has also been described previously [18]. In their case series of four patients, Baron et al suggested that these individuals may have a distinct clinical syndrome, which they referred to as ''mixed immune thrombocytopenia.''…”

Two patients with heparin‐induced thrombocytopenia followed by idiopathic (immune) thrombocytopenic purpura: Case Report

“…On the basis of this experience, the concept of mixed immune thrombocytopenia presented by Baron and colleagues [19] seems more relevant, and it appears that dysfunction of the immune system along with other factors plays a role in the initiation and development of these diseases.…”

“…Concurrent thrombotic thrombocytopenic purpura (TTP) and ITP in both HIV-positive [18] and HIVnegative [19] patients has been reported in the literature, but so far no case of HIT followed by ITP has been reported. On the basis of this experience, the concept of mixed immune thrombocytopenia presented by Baron and colleagues [19] seems more relevant, and it appears that dysfunction of the immune system along with other factors plays a role in the initiation and development of these diseases.…”