Portielje et al evaluated outcomes in adults with idiopathic thrombocytopenic purpura (ITP). This can help identify patients who may benefit from more aggressive or novel therapy. The authors are from Leiden University in The Netherlands.


Patient selection: adult


Criteria for ITP:

(1) platelet count < 100,000 per µL

(2) normal or increased megakaryocytes on bone marrow examination

(3) absence of a clinically apparent cause for thrombocytopenia, including medications


Moderate thrombocytopenia was defined as a platelet count from 30,000 to 100,000 per µL without a count below 30,000 per µL during the first 3 months. Severe thrombocytopenia was defined as a platelet count below 30,000 per µL at any time during the first 3 months.


Parameters affecting outcome:

(1) platelet count at 2 years after diagnosis

(2) need for maintenance therapy

(3) identification of a secondary cause


If a secondary cause for the thromboctyopenia was identified then the relative risk for mortality was 6.0


For patients with ITP:

Platelet Count



> 30,000 per µL


similar to general population

> 30,000 per µL

receiving ongoing maintenance therapy

increased hospital admissions; mortality only slightly increased

<= 30,000 per µL (refractory)

receiving maintenance therapy

increased hospital admissions and increased mortality


Causes of death in refractory patients:

(1) infection

(2) bleeding


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