Association of a positive direct antiglobulin test with chronic immune thrombocytopenia and use of second line therapies in children: A multi‐institutional review

Immune thrombocytopenia (ITP) is the most common autoimmune cytopenia in children. Approximately, 25% of patients develop chronic disease, which may be unpredictable and challenging to treat. It is not currently possible to predict at the time of presentation which patients will have chronic disease or will experience symptoms requiring second‐line therapy defined as treatment beyond corticosteroids, intravenous immunoglobulin, or Rh immune globulin. A multi‐institutional retrospective review of 311 pediatric patients with ITP was performed with the goal of identifying clinical characteristics associated with disease course. In a cohort of 216 patients tested and for whom disease status was known, a positive direct antiglobulin test (DAT) was associated with chronic ITP vs spontaneous resolution of disease (29.2% vs 8.1%, P