Long-term follow-up of idiopathic thrombocytopenic purpura in 310 patients

Abstract

Background and objectives: Idiopathic thrombocytopenic purpura (ITP) induces thrombocytopenia by means of an autoimmune mechanism. Despite the available therapies a subset of patients develop chronic refractory severe thrombocytopenia (i.e. a platelet count consistently lower than 20 to 30x10(9)/L), and life-threatening bleeding can occasionally occur. It has been suggested that the risk of major bleeding is higher in elderly patients and in patients with bleeding at diagnosis. However, since clear data on the influence of clinical and/or laboratory parameters on outcome are lacking, some patients may be receiving unnecessary treatment.

Design and methods: We made a retrospective analysis of a series of 310 patients with chronic ITP (108 males and 202 females), with a median age at diagnosis of 40 years (range 8-87 years). The median follow-up time was 121 months, (range 7-434 months). Therapy was most often started in the presence of hemorrhagic complications and/or a platelet count <30x10(9)/L either at diagnosis or during follow-up.

Results: Our findings confirmed that patients who were symptomatic at diagnosis were more likely to have bleeding during their follow-up. Moreover, all the patients who suffered major bleeding during their follow-up had median platelet counts of 10x10(9)/L (range 1-20) at that time. Only one patient, aged 43 years, died of hemorrhage following prolonged severe thrombocytopenia. Age >60 years was not associated with any significant differences in incidence of bleeding at diagnosis or during follow-up.

Interpretation and conclusions: We conclude that prospective studies are required to evaluate whether it may be reasonable to treat only symptomatic patients, independently of age.