Table 1.
Comparison of patients' characteristics and serum MTX concentrations between patients with and without MTX elimination delay.
| Characteristics | Whole cohort | Number ratio | Normal elimination | Delayed elimination | P value |
|---|---|---|---|---|---|
| Height (cm) | 110 | 123 versus 50 | 110.0 | 108.5 | 0.629 |
| Weight (kg) | 19.0 | 123 versus 50 | 20.0 | 19.0 | 0.493 |
| Age (year) | 5.2 | 123 versus 50 | 5.4 | 5.0 | 0.461 |
| BSA (m2) | 0.85 | 123 versus 50 | 0.75 | 0.75 | 0.615 |
| S-creatinine 0 h (μmol/L) | 31.7 | 110 versus 41 | 32.8 | 30.9 | 0.083 |
| S-creatinine 24 h (μmol/L) | 33.5 | 120 versus 48 | 31.6 | 42.5 | <0.001 |
| S-creatinine 48 h (μmol/L) | 33.8 | 122 versus 50 | 30.5 | 47.4 | <0.001 |
| S-creatinine ratio 24 h | 1.02 | 110 versus 41 | 0.98 | 1.26 | <0.001 |
| S-creatinine ratio 48 h | 1.01 | 110 versus 41 | 0.95 | 1.39 | <0.001 |
| CCR_0 h (mL/min) | 131.3 | 111 versus 41 | 130.1 | 139.5 | 0.424 |
| CCR_24 h (mL/min) | 111.3 | 118 versus 48 | 120.2 | 85.1 | <0.001 |
| CCR_48 h (mL/min) | 102.7 | 120 versus 49 | 114.1 | 81.7 | <0.001 |
| CCR_96 h (mL/min) | 97.7 | 12 versus 17 | 113.8 | 86.4 | 0.008 |
| C MTX_24 h (μmol/L) | 59.8 | 123 versus 50 | 54.5 | 70.5 | <0.001 |
| C MTX_48 h (μmol/L) | 0.43 | 123 versus 50 | 0.32 | 2.81 | <0.001 |
| C MTX_96 h (μmol/L) | 0.04 | 115 versus 49 | 0.02 | 0.25 | <0.001 |
S-creatinine 0 h: serum creatinine level before MTX infusion; S-creatinine 24 h: serum creatinine level in 24 hours after MTX infusion; S-creatinine 48 h: serum creatinine level in 48 hours after MTX infusion; S-creatinine ratio 24 h: the ratio of serum creatinine level in 24 hours to creatinine level before MTX infusion; S-creatinine ratio 48 h: the ratio of serum creatinine level in 48 hours to creatinine level before MTX infusion; CCR_0 h: creatinine clearance rate before MTX infusion; CCR_24 h: creatinine clearance rate in 24 hours after MTX infusion; CCR_48 h: creatinine clearance rate in 48 hours after MTX infusion; CCR_96 h: creatinine clearance rate in 96 hours after MTX infusion; C MTX_24 h: serum MTX concentration in 24 hours after MTX infusion; C MTX_48 h: serum MTX concentration in 48 hours after MTX infusion; C MTX_96 h: serum MTX concentration in 96 hours after MTX infusion.