Predictors of chronic idiopathic thrombocytopenic purpura

Idiopathic thrombocytopenic purpura is a hematological disorder with heterogeneous manifestation and unpredictable outcome. This study reviewed the pattern of presentation and response to therapy in patients with ITP, in order to identify risk factors for chronic disease.

The study included all patients diagnosed as ITP between January 1998 and December 2007.

Sixty-five percent of the patients had acute and 34.9% had chronic ITP. Patients with chronic ITP had a higher mean age at diagnosis (P = 0.0000003). Females more than 10 years of age were more susceptible than males to follow a chronic course (P = 0.031). Febrile illness preceded the onset of ITP in 167 patients, 76.0% of them had an acute course (P = 0.000037). Moderate and severe bleeding occurred in 11.34% and 7.27% of the patients, respectively. Fifty-four patients (15.7%) improved without any specific treatment. Corticosteroids were used as a first-line treatment in 209 patients and showed a total response of 76.6% compared to 85.7% and 84% for IVIG and anti-D immunoglobulin treated patients, respectively.

The most relevant risk factors for the development of chronic ITP included a gradual mode of onset of symptoms over more than 2 weeks period, initial platelet count >20 x 10(9)/L, and age more than 10 years at presentation.