Thrombotic thrombocytopenic purpura:Clinical analysis of 37 cases

Objective:To investigate clinical features,outcome and laboratory characteristics of thrombotic thrombocytopenic purpura(TTP) and improve diagnostic ability for physician in TTP management. Methods:Thirty-seven TTP patients admitted to our hospital from 1998 to 2009 were analyzed. The number of schistocytes per 5,000 red cells was counted at 1000-power magnification. The results were expressed as number of schistocytes per 100 red cells. Results:There were 30 patients(81.1%) with the triad of TTP,including hemolytic anemia,thrombocytopenia and neurologic abnormalities;7(18.9%) had the classical pentad of TTP. Major etiologic factors were acquired autoimmunological abnormalities(35.14%) or idiopathic TTP(56.76%) . The schistocytes of peripheral blood smears were present in all cases with a mean of 4.4% and a range of 0.3%-13.4%. In the studies,plasmapheresis in combination with plasma infusion is the main therapeutic method. 23of 26 patients(88.46%) accepting plasmapheresis achieved complete remission;those patients who only underwent plasma infusion had low remission rate(18%) and high mortality(9/11;82%) . 4 patients with packed RBC infusion manifested transient exacerbation of neurologic or psychiatric symptoms. Conclusions:In conclusion,the diagnosis of TTP is still based on clinical features including evidence of microangiopathic haemolysis and an increased schistocytes count is more valuable and simpler method for the diagnosis of TTP. Plasmapheresis is still the optimal treatment method for TTP patients.