Methods
This single-center retrospective study of newly diagnosed pediatric leukemia patients, 1 to 21 years of age, was conducted at Cohen Children’s Medical Center (New York) from January 2015 to December 2018, after appropriate institutional ethics approval. Inclusion criteria were: new diagnosis of leukemia including pre-B cell acute lymphoblastic leukemia (pre-B ALL), T-cell acute lymphoblastic leukemia (T-ALL), acute myelogenous leukemia (AML), acute promyelocytic leukemia (APL), mature B cell leukemia or biphenotypic leukemia. Exclusion criteria included: prior leukemia diagnosis, leukemia relapse, chemotherapy for leukemia at an outside institution, treatment with steroids within the month prior to presentation, previously diagnosed congenital or acquired coagulopathy (in addition to known or suspected renal or hepatic disease) and transfer to outside institution prior to undergoing procedures. Patients’ relevant history, presenting symptoms (including bleeding/clotting), diagnosis and laboratory values were extracted. Exact Wilcoxon tests and Fisher’s Exact tests were performed, as appropriate, to compare lab values and bleeding symptoms with PT and aPTT.