Reproducibility of serial creatinine excretion measurements in peritoneal dialysis

Table 2 Creatinine excretion in patients with two studies

Variable	1st clearance study	2nd clearance study	P value
PD duration, mo	9.2 ± 15.2	17.4 ± 15.8
VU, L/24-h	0.54 ± 0.63	0.40 ± 0.53	< 0.001
VD, L/24-h	11.3 ± 3.2	12.1 ± 3.6	NS
Kt/V urea, weekly	2.30 ± 0.62	2.12 ± 0.03	0.003
CCr, L/1.73 m2, weekly	77.9 ± 32.1	67.9 ± 18.2	0.002
SUN, mg/dL	49.7 ± 15.1	49.4 ± 16.2	NS
[Cr]S, mg/dL	9.1 ± 3.3	10.1 ± 3.4	0.001
EXCr U, mg/24-h	406 ± 337	286 ± 350	0.003
EXCr D, mg/24-h	680 ± 337	769 ± 390	< 0.001
EXCr T, mg/24-h	1087 ± 470	1055 ± 421	NS

PD: Peritoneal dialysis; NS: Not significant; VU: Urine volume; VD: Drained volume of spent dialysate; Kt/V urea: Fractional urea clearance, weekly; C_Cr: Weekly renal plus peritoneal creatinine clearance; SUN: Serum urea nitrogen; [Cr]_S: Serum creatinine concentration; EX_Cr D: Creatinine excretion in spent dialysate; EX_Cr U: Creatinine excretion in urine; EX_Cr T: Total creatinine excretion in urine plus dialysate.