en Pediatric Hematology & Oncology Pediatric Hematology & Oncology پژوهشي Original Article Background: Efficacy of rasburicase in pediatric patients with leukemia and lymphoma is proved. This study aims to<br>weigh efficacy and safety of rasburicase versus more conventional therapy, allopurinol, and to compare their safety<br>and properties in tumor lysis syndrome (TLS) of leukemia and lymphoma patients.<br>Materials and Methods: The study was done with a retrospective cohort design. Patients were selected from our<br>hematology ward admitted from 2005 through 2008. Patients were put into two groups based on their blood levels<br>of uric acid, before initiation of chemotherapy treatment group (the Uric Acid level of 6.5 mg/dl or more) and the<br>prophylaxis group (the uric acid level below 6.5 mg/dl). Evaluation of effectiveness of therapy was performed after<br>24, 48, 72-hour, and longer periods.<br>Results: Of 184 patients 69% had leukemia, and 31% lymphoma. Twenty patients were treated with rasburicase<br>and 164 with allopurinol. Mean age of patients was 7.93± 4.247 years old. 60.8% were male and 39.2% were female.<br>According to Chi-square test results, there was no significant difference between two agents regarding prophylaxis<br>(chi-square = 4.247, p-value = 0.193) and treatment (chi-square = 0.780, p-value = 0.677). Most of the response to<br>each agent was seen in the first 24 hours after drug administration. Mean level of uric acid reduced from 7.4 to 3.4<br>mg/dl in rasburicase, and from 5.4 to 3.9 mg/dl in allopurinol group. Mean duration of treatment for rasburicase was<br>2 days, and for allopurinol 6 days. Adverse effects were minimal in both groups (in rasburicase 1.6% and in allopurinol<br>5.4%).<br>Conclusion: Rasburicase seems to be highly efficient in both prophylaxis and treatment of Hyperuricemia. Due to<br>high costs in our practice, it was only administered to 20 patients with high levels of blood uric acid or leukocytosis.<br>It prepares patients for chemotherapy faster and decreases cost of hospital stay indirectly by lowering cost of<br>treatment. Allopurinol, alternatively showed equal efficiency and comparable results. Thus, it can be used safely and<br>effectively until rasburicase becomes more widely available and more cost-effective. Hyperuricemia, Rasburicase, Allopurinol, Leukemia, Lymphoma 61 66 http://ijbc.ir/browse.php?a_code=A-10-2-171&slc_lang=en&sid=1