Fatemeh Afsharirad,1Saman Hakimian,2,*
1. Bachelor student of Midwifery Azad University of Zanjan 2. M.sc student of Microbiology Islamic Azad University Central Tehran Branch, Iran,Tehran
Introduction: Pediatric acute Lymphoblastic leukemia (ALL) is the most common cancer in children and adolescents. Current treatment protocols have very high cure rates. However, the use of chemotherapy agents has increased the incidence of thrombotic events and is the second cause of death in this group of patients. Patients with ALL are susceptible to pulmonary thromboembolic complications (VTE). The pathogenesis and incidence of VTE play an important role and have a significant impact on children. According to the studies, changes in hemostasis of children with leukemia can be detected before treatment. In the studies of Mitchell et al., a significant increase in some coagulation factors, a significant decrease in pre-coagulation hemostatic proteins and natural coagulation inhibitors were observed. It seems that the occurrence of thrombosis in ALL is related to the presence of central venous lines (CVL), comorbidities and the type of treatment performed. Most treatment-related events occur during the induction phase.
Asparaginase (ASP) and steroids are the main components of chemotherapy protocols for ALL. It seems that the simultaneous use of steroids increases the risk of thrombotic events. According to the available data, there is a direct relationship between the administration of L-asparaginase and the occurrence of thrombosis. Many related events occur in the venous system; Although arterial thrombosis has also been reported (especially in adults). Thrombosis occurs in half of the cases in the central nervous system (CNS) reported in ALL patients treated with L-asparaginase. The reports of studies by Parasole et al. have shown that patients treated with ASP suffered from ischemic-hemorrhagic strokes.
Methods: Catheter-related thrombosis is the most common thrombotic event in ALL. In the studies of KU et al., it is stated that the use of intravenous catheters along with old age and the presence of concomitant diseases is an important factor for predicting thrombosis in ALL. In the study, it was shown that age plays an important role in the development of thrombotic complications. ; While there is no demonstrable effect on the relationship between gender and the incidence of thrombosis caused by ALL.
Treatment of such complications is challenging due to severe thrombocytopenia and high risk of bleeding. Unfractionated heparin (VFH) and low molecular weight heparin (LMWH) are used in ALL patients to treat acute deep venous thrombosis (DVT) and pulmonary embolism (PE). Vitamin K antagonists are the treatment of choice for VTE, but their use is associated with bleeding in cancer patients.
Results: This study emphasizes the need for prospective studies to identify ALL patients at risk of thrombotic complications. This requires strategies to reduce thrombotic complications, increase safety and The performance of treatment protocols during the course of the disease is reminded.
Conclusion: The results of several clinical trials have shown that replacing heparin with Enoxaparin improved the signs and symptoms of venous thrombosis within a few days and reduced the incidence of bleeding during treatment. However, no improvement in the number of platelets has been observed.
The fact that the pathogenesis of coagulation activation in cancer patients is complex and multifactorial is well known. On the other hand, thrombotic events in ALL are one of the important causes of mortality complications. This study emphasizes the need for prospective studies to identify ALL patients at risk of thrombotic complications.