Prophylactic treatment with fresh‐frozen plasma in chronic thrombotic thrombocytopenic purpura

Abstract

We read with interest the article of Barbot et al (2001), which described a patient with chronic relapsing thrombotic thrombocytopenic purpura (TTP) associated with congenital deficiency of von Willebrand factor-cleaving protease who has been treated with regular prophylactic administration of fresh-frozen plasma (FFP) for the last 10 years. This patient has so far received 160 units of FFP and remains free from demonstrable transfusion-associated viral infections. This report suggests that long-term prophylactic therapy with FFP is not only an effective treatment for this condition but also safe. This conclusion is supported by our experience with a patient with TTP who has been treated with fortnightly FFP infusions for 23 years! Our patient, a 46-year-old Caucasian woman, was diagnosed with thrombotic thrombocytopenic purpura in 1978 when she presented with convulsions during pregnancy. However, she has had a history of recurrent anaemia and thrombocytopenia from the age of 18 months. She was commenced on prophylactic therapy with freshfrozen plasma (FFP), initially one unit weekly and subsequently every fortnight. Attempts to tail off the treatment resulted in recrudescence of symptoms. She has therefore been maintained on a fortnightly infusion of FFP ever since. She has had no untoward reactions to the treatment and clinically she remains well. Her haematological parameters including haemoglobin level and platelet count are normal. A virology screen for hepatitis A, B and C was negative. Her base-line (pre-FFP infusion) von Willebrand factor metalloproteinase activity carried out in May 2000 was < 2%, supporting a diagnosis of TTP associated with unusually large von Willebrand factor multimers due to impaired degradation to smaller molecular forms, similar to the case reported by Barbot et al (2001). Our patient has so far received over 650 units of FFP. The clinical history of this patient thus supports the assertion of Barbot et al (2001) that long-term prophylactic treatment with FFP is a feasible, effective and relatively safe option for patients with a chronic relapsing form of TTP.