Prospective registry of adult patients receiving therapeutic plasma exchange with a presumptive diagnosis of thrombotic microangiopathy (TMA): The Turkish hematology research and education group (ThREG)-TMA02 study

Thrombotic microangiopathy(TMA) is a pathological diagnosis characterized by abnormalities of small vessels leading to microvascular thrombosis of arterioles and capillaries. The current prospective, non-interventional, multicenter (n:18) study aimed to define distribution of different TMA forms in adult Turkish patients who were referred for therapeutic plasma exchange (TPE) for a presumptive diagnosis of TMA. Patients with serum ADAMTS13 activity 10 %, normal renal function and no secondary TMA were treated as unclassified TMA. The study included a total of 97 patients (female: 60; male: 30) with a median age of 48 (18-74). Detailed evaluation at 1 month after hospital admission revealed aTTP, secondary TMA, infection/complement-associated hemolytic uremic syndrome and unclassified TMA in 32 (33 %), 33 (34 %), 26 (27 %) and 6 (6%) patients respectively. As subclassification of various TMAs will dictate specific therapy, proper diagnosis in a timely manner is of utmost clinical significance.