Prolonged Prothrombin Time Does Not Correlate with Clinical Bleeding
Symptoms in Newly Diagnosed Pediatric Leukemia Patients
Abstract
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.