β-Trace Protein, Cystatin C, β2-Microglobulin, and Creatinine Compared for Detecting Impaired Glomerular Filtration Rates in Children

Abstract

Background: Because of the limitations of serum creatinine as a marker of glomerular filtration rate (GFR) in children, we assessed the diagnostic accuracy of the novel marker β-trace protein (BTP) in comparison with cystatin C (Cys-C), β2-microglobulin (β2-MG), and creatinine as conventional indicators of reduced GFR. Methods: We obtained serum samples from 225 children (age range, 0.2–18 years) with various renal pathologies who were referred for nuclear medicine clearance investigations (technetium-diethylenetriamine pentaacetic acid or chromium-EDTA). We measured Cys-C, BTP (nephelometric tests; Dade Behring), β2-MG (Tinaquant; Roche), and creatinine (enzymatic assay; Creatinine-PAP; Roche). Results: Seventy-five children had reduced GFR (<90 mL · min−1 · 1.73 m−2). One hundred fifty children (independent of gender and age) with values >90 mL · min−1 · 1.73 m−2 comprised the control group with gaussian distributions of BTP and Cys-C concentrations. The upper reference limits (97.5 percentile) were 1.01 mg/L for BTP and 1.20 mg/L for Cys-C. The correlations of nuclear medicine clearance with the reciprocals of BTP, Cys-C, and the Schwartz GFR estimate were significantly higher (r = 0.653, 0.765, and 0.706, respectively; P <0.05) than with the reciprocal of creatinine or β2-MG (r = 0.500 and 0.557, respectively). ROC analysis showed a significantly higher diagnostic accuracy of BTP, Cys-C, and the GFR estimate for the detection of impaired GFR than serum creatinine (P <0.05). Compared to creatinine, BTP increased the diagnostic sensitivity by ∼30%, but it was not more sensitive than Cys-C or the Schwartz GFR estimate. Conclusions: BTP is superior to serum creatinine and an alternative for Cys-C to detect mildly reduced GFR in children, but it is not better than the Schwartz GFR estimate.

Effects of Oral Prednisone Administration on Serum Cystatin C in Dogs

“…[10][11][12][13][14][15][16][17][18][19][20][21] However, it has to be noted that the treatment of choice for all these conditions include exogenous glucocorticoid administration and that methylprednisolone or prednisone administration deeply influence sCysC in humans. 10,15,22 In veterinary medicine, reference values for sCysC canvary with age and body weight (<15 kg), 23 these results are controversial. 24,25 Other conditions such as fasting 23 or leishmaniasis 26,27 influence sCysC in dogs.…”

Beta2‐microglobulin is a better predictor of treatment‐free survival in patients with chronic lymphocytic leukaemia if adjusted according to glomerular filtration rate

“…As a consequence, B2M levels dramatically increase in patients with impaired renal function. Indeed, B2M levels have been advocated as a better predictor of glomerular filtration rate (GFR) than creatinine serum levels, particularly in children (Filler et al, 2002).…”

Commentary: Clinical diagnostic use of cystatin C

“…In both populations, low muscle mass may produce low sCr values that do not reflect true underlying GFR, and may obscure small changes in true GFR in ranges where analytical imprecision is greatest. In his ROC analysis of four approaches (sCysC, beta(2)-M, beta-trace protein, and sCr) to GFR determination in a large group of children with various renal diseases, Filler et al (31) found that sCysC was superior to sCr in detecting mild decreases in GFR when compared to an exogenous gold standard tracer. However, using ROC analysis in studies of elderly populations, Van Den Noortgate et al (32) found that sCysC determination did not offer improved detection of decreased GFR when compared with exogenous tracers.…”