Predictors of Steroid Resistance in Pediatric Acute Immune Thrombocytopenic Purpura

Immune thrombocytopenia (ITP, platelet counts < 100 × 109/L) is the most common acquired childhood bleeding disorder, clinically characterized by a low platelet count in the absence of other thrombocytopenia causes [1,2].

The estimated incidence of ITP is 100 cases out of a million people per year; about half of these cases occur in previously healthy children, where it represents the most frequent blood disorder [3].

Most children present with a typical history of acute purpura and bruising after a mild viral infection [4]. In severe cases, intracranial hemorrhage (the most 0.5% serious complication, but also the rarest occurring in adults), gastrointestinal hemorrhage in 1.5 % of children, and genitourinary hemorrhage may occur [5].

The International Working Group on ITP defines ITP according to the following clinical phases [6]. These are as follows:

Newly diagnosed ITP is in the first three months post-diagnosis. Persistent ITP is for 3-12 months. Chronic ITP is for > 12 months. Refractory ITP is the failure to restore count of platelet after splenectomy. For children requiring therapy but without life threatening bleeding, corticosteroids are the recommended first line therapy over IVIG or anti-D [2].