Beta-trace protein is not superior to cystatin C for the estimation of GFR in patients receiving corticosteroids

• Published in: Clinical biochemistry 2008-03, Vol.41 (4), p.299-305
• Main Authors: Abbink, Floor C.H., Laarman, Céleste A.R.C., Braam, Katja I., van Wijk, Joanna A.E., Kors, Wijnanda A., Bouman, Anna A., Spreeuwenberg, Marieke D., Stoffel-Wagner, Birgit, Bökenkamp, Arend
• Format: Article
• Language: English
• Subjects: Adolescent; Adrenal Cortex Hormones - pharmacology; Adrenal Cortex Hormones - therapeutic use; Beta-trace protein; Child; Child, Preschool; Corticosteroids; Cystatin C; Cystatins - blood; Female; Glomerular filtration rate; Glomerular Filtration Rate - drug effects; Humans; Hypoglycemic Agents - administration & dosage; Hypoglycemic Agents - pharmacokinetics; Insulin - administration & dosage; Insulin - pharmacokinetics; Intramolecular Oxidoreductases - blood; Kidney Function Tests; Lipocalin prostaglandin D2-synthase; Lipocalins - blood; Male; Metabolic Clearance Rate - drug effects; Prednisone - pharmacology; Prednisone - therapeutic use
• ISSN: 0009-9120; 1873-2933
• DOI: 10.1016/j.clinbiochem.2007.11.012

Comparison of the effect of corticosteroid therapy on the diagnostic performance of cystatin C (Cys) and β-trace protein (bTP), two endogenous markers of GFR. Out of a total of 193 pediatric inulin clearance studies, a random sample of 85 steroid-free studies served to establish GFR prediction equations (eGFR), which were used to compare the remaining 76 steroid-free and 32 steroid-positive studies (median prednisone dose 33.0 mg m − 2 day − 1 ). We found a positive relationship between prednisone dose and eGFR βTP ( b = 0.414, p = 0.0002) and a negative relationship with eGFR cys ( b = −0.208, p = 0.0091). Only Cys independently predicted GFR below 90 mL min − 1 1.73 m − 2 , both in steroid-positives ( b = 6.260, p = 0.010) and steroid-negatives ( b = 6.845, p = 0.012). Glucocorticoid therapy did not affect the accuracy in estimating GFR within 30% of measured GFR for Cys, while accuracy was lower with bTP (65.6% vs. 81.6%, p = 0.08). Glucocorticoids have less impact on the diagnostic accuracy of Cys than bTP.