COMPARISON OF SCHWARTZ EGFR-CR WITH GFR MEASURED BY TC-99M-DTPA CLEARANCE IN HEALTHY CHILDREN AND IN CHILDREN WITH URINARY TRACT INFECTION WITH AND WITHOUT VESICOURETERAL REFLUX
Acta Medica Medianae
The aim of this study was to assess the diagnostic reliability of the estimated glomerular filtration rate based on serum creatinine and body height (eGFR-Cr Schwartz) as compared to the glomerular filtration rate (GFR) measured by a radioisotope method using Tc-99m-DTPA clearance in healthy children and in children with urinary tract infections (UTI) with and without a vesicoureteral reflux (VUR) using Bland-Altman analysis. The retrospective study enrolled 451 paediatric patients (104 male
... tients (104 male and 347 female, aged 7.07 ± 3.02, range of 2-15) from a single-institution database. Groups of participants were formed according to their diagnosis: the control group (CG, n = 64), the group with UTI with no documented VUR (UTI, n = 299), and the group with UTI and VUR (VUR, n = 88). The GFR was measured by the Tc-99m-DTPA clearance from a single blood sample drawn 180 minutes after administering the radiopharmaceutical. The eGFR-Cr was determined from an equation which included body height and the serum creatinine level. When compared to Tc-99m-DTPA GFR, the eGFR-Cr yielded the following mean deviation values in the examined groups: CG: 1.937 ml/min/1.73m 2 (95% limits of agreement [LOA]: -36.759-40.633 ml/min/1.73m 2 ), UTI: -3.010 ml/min/1.73m 2 (LOA: -57.292-51.272 ml/min/1.73m 2 ) and VUR: 2.183 ml/min/1.73m 2 (LOA: -64.019-68.385 ml/min/1.73m 2 ). eGFR-Cr demonstrated comparable accuracy to Tc-99m-DTPA GFR in the CG and UTI groups with 95% and 82% of values within 30% of the Tc-99m-DTPA GFR. The eGFR-Cr demonstrated a lower measurement reliability in the VUR group, amounting to only 68% of the values within 30% of the Tc-99m-DTPA clearance. The results proved eGFR-Cr to be a reliable alternative to the radioisotope method in children with preserved renal function and children with a urinary tract infection with no reflux, but a less reliable method in children with both VUR and renal impairment.