Hyperleukocytosis and Exchange Transfusion in Pediatric Acute Leukemia: Literature Review Rayhan Hafidz1, Arina Setyaningtyas2,3* Abstract Hyperleukocytosis is a life-threatening oncologic emergency frequently encountered in patients with acute leukemia. It is defined as a peripheral leukocyte count exceeding 100,000/µL and is most commonly observed in acute lymphoblastic leukemia (ALL) and acute