Incidence and Outcomes of Tumor Lysis Syndrome in Pediatric Lymphohematopoietic Malignancies: A Single-Center Study

Background: Tumor lysis syndrome (TLS) occurs when intracellular contents are released into the bloodstream, either spontaneously or following anticancer therapies such as chemotherapy or radiotherapy. This syndrome is characterized by hyperuricemia, hyperkalemia, hyperphosphatemia, and hypocalcemia. Objectives: The aim of this study was to determine the incidence and outcomes of TLS in pediatric lymphohematopoietic malignancies. Methods: This descriptive cross-sectional study reviewed the medical records of all patients diagnosed with lymphohematopoietic malignancies and hospitalized at Ali Ibn Abi Talib Hospital, Zahedan, between October 2014 and March 2019. Patients meeting the diagnostic criteria for TLS were identified, and their demographic, clinical, and laboratory data were collected. Data were analyzed using SPSS version 25. Results: The study included 93 children with a mean age of 6.65 ± 4.42 years; 66 (71%) were male, and 27 (29%) were female. Fourteen patients (15.1%) were diagnosed with laboratory TLS, and 5 (5.4%) with clinical TLS. The highest incidence of laboratory TLS was observed in patients with B-cell acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL) (28.5% each). Among metabolic disturbances, hyperphosphatemia was the most common (33.3%), while hyperkalemia was the least common (8.6%). Overall, patients with TLS exhibited higher initial white blood cell (WBC) counts compared to non-TLS patients. Conclusions: This study revealed that laboratory TLS occurred in 15% of pediatric hematopoietic malignancies, with more than 50% experiencing at least one metabolic disturbance. Prevention and timely intervention during treatment are crucial to reducing the occurrence of clinical TLS and improving patient outcomes.