Evaluation of Gentian cystatin C reagent on Abbott Ci8200 and calculation of glomerular filtration rate expressed in mL/min/1.73 m²from the cystatin C values in mg/L

Abstract

There was low inter-laboratory variation between the three laboratories involved in the cystatin C evaluation, and thus all three laboratories can use the same equation for calculating the estimated GFR.

Soluble tumor necrosis factor receptor 1 (sTNFR1) is associated with increased total mortality due to cancer and cardiovascular causes – Findings from two community based cohorts of elderly

“…The assays had a total coefficient of variation (CV) of approximately 6%. Cystatin C was measured by latex-enhanced reagent (NLatexCystatin C; Siemens, Deerfield, IL, USA) using a BN ProSpec analyser (Siemens) and used to estimate GFR in ULSAM [11], and by latex-enhanced reagents (Gentian, Moss, Norway) using an Architect ci8200 (Abbott Laboratories, Abbott Park, IL, USA) in PIVUS [12]. High-sensitive CRP measurements were performed by latex-enhanced reagent (Siemens) with the use of a BN ProSpec® analyzer (Siemens) in ULSAM and with the use of an Architect ci8200 in PIVUS [13].…”

Analytical study of three cystatin C assays and their impact on cystatin C-based GFR-prediction equations

“…We have recovered the results of precedent studies regarding the absence of significant interferences of the different assays with hemolysis, lipemia and bilirubin [5,11,[18][19][20]. The Gentian assay uses avian antibodies (the two other assays use rabbit antibodies) and some authors have hypothesized that using such avian antibodies will strongly reduce analytical interferences, notably with RF [11,12]. For this reason, we have deeply studied potential RF interferences by two different methods.…”

“…Applying the Dako and the Gentian cystatin C in the Levey equation is maybe more questionable, in term of systematic bias (difference of ± 6 mL/ min/1.73 m 2 ) and especially in term of precision. The first comparisons published between the Gentian and the Siemens affirming the equivalence between both methods seem thus a little too optimistic [11,24]. Moreover, as it is shown in Fig.…”

“…We also evaluated the possible interference of the rheumatoid factor (RF), as one of the kits (Gentian) was designed with avian antibodies being thus presented as better regarding RF interferences [11,12].…”

New Combined Serum Creatinine and Cystatin C Quadratic Formula for GFR Assessment in Children

“…Regression coefficients were calculated independently of the published coefficient equations (5,6,(16)(17)(18)(19). As shown in Figure 1, the scatter plot that graphically appears to be the closest to a straight line was the one performed without transformation of CysC, in favor of a linear relationship between CysC and iGFR.…”