Comparison of predictive accuracy of teicoplanin concentration using creatinine clearance and glomerular filtration rate estimated by serum creatinine or cystatin C

Background: Conventional estimates of glomerular dysfunction, including serum creatinine and creatinine clearance, are inadequate in older people. In this study we have compared the diagnostic accuracy of a novel test of kidney disease, cystatin C, against these markers in older patients with a range of renal function. Methods: Fifty-three patients (mean age 79.6 years, range 69-92 years) with a variety of medical diagnoses were recruited via outpatient clinics. Exclusion criteria included active rheumatoid disease, known current malignancy, renal replacement therapy/renal transplantation and cognitive impairment. 51Cr-EDTA was used as the reference method against which the other markers of glomerular filtration rate were compared using regression analyses. Results: The best fit with glomerular filtration rate was given by Cockcroft and Gault calculated clearance ( R2 = 0.83), followed by serum cystatin C ( R2 = 0.79), serum creatinine ( R2 = 0.76) and creatinine clearance ( R2 = 0.73). The accuracy for glomerular filtration rate prediction was poor for all markers. Serum cystatin C detected nearly all patients with mild renal impairment whereas serum creatinine only detected half of these cases. Regression modelling predicted that the upper limit of normal for serum cystatin C would be exceeded as glomerular filtration rate fell below 64 mL/min/1.73 m2, compared with 44 mL/min/1.73 m2 for serum creatinine. Conclusion: Serum cystatin C is a simple and sensitive screening test for kidney dysfunction in older people.

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Is serum cystatin C the marker of choice to predict glomerular filtration rate in paediatric patients?

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1258/000456303321016178 ◽

2003 ◽

Vol 40 (1) ◽

pp. 60-64 ◽

Cited By ~ 20

Author(s):

Hans L. Willems ◽

Luuk B. Hilbrands ◽

John F. van de Calseyde ◽

Leo A.H. Monnens ◽

Dorine W. Swinkels

Keyword(s):

Glomerular Filtration Rate ◽

Serum Creatinine ◽

Creatinine Clearance ◽

Glomerular Filtration ◽

Cystatin C ◽

Filtration Rate ◽

Inulin Clearance ◽

Serum Cystatin C ◽

Serum Cystatin ◽

Endogenous Creatinine Clearance

Background: It has been suggested that serum cystatin C (cyst-C) concentration provides a better indication of changes in glomerular filtration rate (GFR) than does serum creatinine concentration. Methods: Because of conflicting results as to the usefulness of cyst-C, we compared the GFRs calculated from serum cyst-C, inulin clearance and endogenous creatinine clearance in children. GFRs calculated from cystatin concentration, inulin clearance following a single injection and endogenous creatinine clearance using Jaffé and enzymic methods were compared in 66 children (1·3-21·9 years) with a variety of renal disorders. Receiver operating curve analysis was used to determine the cut-off value that would give the best discrimination between normal and decreased GFR. Results: The serum cyst-C concentration ranged from 0·66 to 7·61 mg/L (median 1·94). Serum creatinine Jaffé concentration (creat-J) ranged from 38 to 871 µmol/L (median 105) and creatinine enzymatic concentration (creat-E) ranged from 28 to 862 µmol/L (median 126). The linear correlation coefficient ( R) of 1/cyst-C versus GFR ( R = 0·937) did not differ from either that of 1/creat-J versus GFR ( R = 0·918) or that of 1/creat-E versus GFR ( R = 0·901). These coefficients had overlapping confidence intervals. The areas under the curve for cyst-C, creat-J and creat-E were 0·967, 0·977 and 0·924, respectively, and were not significantly different from each other. For cyst-C, the optimal cut-off was 1·1 mg/L. Conclusions: Serum cyst-C is equivalent to creat-J and creat-E as a marker for estimating the GFR in the paediatric population studied.

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Serum NGAL, BNP, PTH, and albumin do not improve glomerular filtration rate estimating formulas in children

European Journal of Pediatrics ◽

10.1007/s00431-021-04019-w ◽

2021 ◽

Author(s):

Julie Mouron-Hryciuk ◽

François Cachat ◽

Paloma Parvex ◽

Thomas Perneger ◽

Hassib Chehade

Keyword(s):

Glomerular Filtration Rate ◽

Parathyroid Hormone ◽

Serum Creatinine ◽

Brain Natriuretic Peptide ◽

Glomerular Filtration ◽

Natriuretic Peptide ◽

Cystatin C ◽

Filtration Rate ◽

Neutrophil Gelatinase Associated Lipocalin ◽

Neutrophil Gelatinase

AbstractGlomerular filtration rate (GFR) is difficult to measure, and estimating formulas are notorious for lacking precision. This study aims to assess if the inclusion of additional biomarkers improves the performance of eGFR formulas. A hundred and sixteen children with renal diseases were enrolled. Data for age, weight, height, inulin clearance (iGFR), serum creatinine, cystatin C, neutrophil gelatinase-associated lipocalin (NGAL), parathyroid hormone (PTH), albumin, and brain natriuretic peptide (BNP) were collected. These variables were added to the revised and combined (serum creatinine and cystatin C) Schwartz formulas, and the quadratic and combined quadratic formulas. We calculated the adjusted r-square (r2) in relation to iGFR and tested the improvement in variance explained by means of the likelihood ratio test. The combined Schwartz and the combined quadratic formulas yielded best results with an r2 of 0.676 and 0.730, respectively. The addition of BNP and PTH to the combined Schwartz and quadratic formulas improved the variance slightly. NGAL and albumin failed to improve the prediction of GFR further. These study results also confirm that the addition of cystatin C improves the performance of estimating GFR formulas, in particular the Schwartz formula.Conclusion: The addition of serum NGAL, BNP, PTH, and albumin to the combined Schwartz and quadratic formulas for estimating GFR did not improve GFR prediction in our population. What is Known:• Estimating glomerular filtration rate (GFR) formulas include serum creatinine and/or cystatin C but lack precision when compared to measured GFR.• The serum concentrations of some biological parameters such as neutrophil gelatinase-associated lipocalin (NGAL), parathyroid hormone (PTH), albumin, and brain natriuretic peptide (BNP) vary with the level of renal function. What is New:• The addition of BNP and PTH to the combined quadratic formula improved its performance only slightly. NGAL and albumin failed to improve the prediction of GFR further.

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