Steroid Resistance in Pediatric 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].

Guidelines from the American Society of Hematology recommend a 5-7-day course of prednisone dosed at 2-4 mg/kg/day [2]. Seventy-five percent of children respond to steroids, with platelets recovering to hemostatic range by 2-7 days [7]. If a more rapid rise in platelets is desired, IV methylprednisolone may be used. Studies comparing outcomes between anti-D versus methylprednisolone [8] and comparing methylprednisolone with dexamethasone [9] showed similar response rates with minor side effects in all groups.

A study shows that 98% of patients with corticosteroid exposure experienced one or more side events, and 38% of patients need to stop or reduce corticosteroid therapy [10].

This research aims to develop a new prediction model to evaluate whether newly ITP patients are at high-risk of corticosteroid resistance, and help clinicians to choose better therapy so we divide patients to two groups, steroid response and steroid resistance.

Inclusion criteria

• All patients diagnosed as acute immune thrombocytopenic purpura based on clinical manifestations and laboratory investigations from age of 1 years to age of 18 years.

Gender: both six

Exclusion criteria

• children with immune thrombocytopenic purpura below age of 1 years and above 18 years, patient with thrombocytopenic purpura with secondary causes, and chronic ITP