Comparison of intravenous immunoglobulin and high dose anti‐D immunoglobulin as initial therapy for childhood immune thrombocytopenic purpura: response Özsoylu

Abstract

We thank Dr. Ozsoylu for his comments on our article describing the comparison of intravenous immune globulin (IVIG) and high dose anti-D immune globulin in the management of childhood immune thrombocytopenic purpura (ITP) (Kane et al, 2010). We would like to emphasize that our study was not designed to include a control group (consisting of no treatment) or a methylprednisone group. While controversial (particularly in the UK, where watchful waiting is an accepted option), the standard of care at our institution in the United States has been to treat ITP with IVIG or anti-D to quickly reverse severe thrombocytopenia. Although most cases of ITP will resolve without treatment, it is thought that increasing the platelet count decreases the risk (however remote) of intracranial haemorrhage. We do not dispute that steroids are a viable treatment option for ITP, particularly when the cost of treatment is considered. Multiple studies have established the feasibility of steroids as a treatment for ITP (Ozsoylu & Erturk, 1991; Blanchette et al, 1994). High dose steroids (30 mg/kg × 3 d then 20 mg/kg × 4 d) may offer quicker platelet response, making it a more attractive option compared to IVIG or anti-D. Also, a short course of oral prednisone (4 mg/kg per day) without tapering has been shown to significantly increase the platelet count in children with ITP (Carcao et al, 1998). However, steroids come with their own risk profile, and a new study suggests that high dose treatment is associated with an increased risk of osteonecrosis (Yildirim et al, 2008). More importantly, our institution, like many in the United States, has avoided steroids as a first-line agent for childhood ITP because bone marrow aspirates are not routinely done to rule out malignancy first. Though rare, leukaemia misdiagnosed as ITP and partially treated with steroids could result in initial clinical improvement followed by the development of a more steroid-resistant malignancy.