Prolonged prothrombin time (PT) and/or activated partial thromboplastin time (aPTT) are frequently seen in newly diagnosed pediatric leukemia patients (NDPLP), which can lead to delayed diagnostic and therapeutic procedures due to concern for bleeding. In this single center retrospective study of NDPLP we analyzed these parameters in 93 patients (aged 1-21 years). None had a personal history of bleeding, but 33.3% had bleeding symptoms within 30 days of presentation, predominantly mucosal bleeding (80.6%) and petechiae (64.5%). Median laboratory values at diagnosis: white blood cell count 15.7, hemoglobin 8.1, platelets 64, PT 13.2, and a PTT 31. Red blood cells were administered in 41.2%, platelets in 52.9%, FFP in 7.8%, and vitamin K in 21.6% based on institutional cut-off values for replacement or clinical symptoms. Prolonged PT was found in 54.8% of patients (factor VII 33.1% (interquartile range [IQR] 19.4-50.5), while aPTT was prolonged in 5.4%. Anemia and thrombocytopenia did not correlate with prolonged PT (p=0.73 and p=0.18 respectively), or prolonged aPTT (p=0.52 and 0.42). Leukocytosis and neutrophilia showed significant correlation with elevated PT (p<0.001 and <0.01 respectively), but not aPTT (p=0.3 and 0.5). Bleeding symptoms upon presentation did not correlate with prolonged PT (p=0.83), prolonged aPTT (p=1) or anemia (p=0.06) but had significant correlation with thrombocytopenia (p=<0.0001) and elevated AST (p=0.05). Therefore, a prolonged PT in NDPLP may not necessitate the reflexive use of blood product replacement in the absence of significant bleeding, which is likely related to leukocytosis than to a true coagulopathy.
