Related Experiment Video
Updated: Jan 6, 2026

Murine Model of Leukemia Relapse to Induction Chemotherapy for Acute Lymphoblastic Leukemia
Published on: October 17, 2025
The relationship between urine output and time to methotrexate clearance in pediatric leukemia patients receiving
Yi-Lun Wang1, Tsung-Yen Chang1, Shih-Hsiang Chen1
1Divisions of Hematology/Oncology, Department of Pediatrics, Chang Gung Children's Hospital, Chang Gung University, 5 Fu-Shin Street, Kwei-Shan, Taoyuan, 333, Taiwan.
Background:
High-dose methotrexate (HD-MTX) is a cornerstone of pediatric acute lymphoblastic leukemia (ALL) treatment but poses a risk for delayed clearance and associated toxicities. While hydration is standard to enhance methotrexate (MTX) excretion, the relationship between urine output (UO) and time to MTX clearance remains underexplored.
Methods:
We conducted a retrospective study of pediatric ALL patients treated with HD-MTX at Chang Gung Memorial Hospital between August 2023 and February 2025. Patients were stratified into higher (H-UO) and lower urine output (L-UO) groups using a 5.0 mL/kg/hr cutoff. Clinical outcomes including time to MTX normalization, delayed MTX clearance, hospitalization duration, and use of adjunctive diuretics were analyzed.
Results:
Thirty-nine patients were included. The H-UO group showed significantly faster MTX clearance (2.0 vs. 4.0 days, P = 0.0035), lower incidence of delayed clearance (18.2% vs. 70.6%, P = 0.0025), and shorter hospital stays (5.0 vs. 7.0 days, P = 0.019). Diuretic use was higher in the L-UO group, primarily as a reactive measure. No significant difference in MTX-related major toxicities was observed.
Conclusions:
Higher UO is associated with more efficient time to MTX clearance and shorter hospitalization in pediatric ALL patients receiving HD-MTX. Prospective studies are warranted to optimize supportive care protocols.
Related Concept Videos
Pharmacokinetics in Pediatric Patients: Drug Excretion
Pharmacokinetics in Pediatric Patients: Drug Metabolism
Drug Dosing in Renal Diseases: Dose Adjustments Based on Drug Clearance and Elimination Rate Constant
Drug Dosing in Renal Diseases: Measurement of Serum Creatinine Concentration and Clearance
Factors Affecting Renal Clearance: Renal Impairment
One condition associated with renal failure is uremia. Uremia is characterized by impaired glomerular filtration and fluid accumulation in the body. This condition hinders the renal clearance of drugs, resulting in drug accumulation and potential...
Renal Failure: Dose Adjustments
Reduced renal clearance and elimination rate are common outcomes of renal impairment. These alterations lead to a prolonged elimination half-life and an altered apparent volume of distribution for drugs. As a result, dosage adjustments are typically necessary to maintain optimal drug levels in the body.
However, dosage adjustments...

