Cystatin C vs creatinine as markers of renal function in patients on digoxin treatment

Abstract

In this study, serum cystatin C correlated better to serum digoxin than did serum creatinine. With improved GFR monitoring, digoxin concentrations should be better controlled.

Estimation of the Glomerular Filtration Rate From Serum Creatinine and Cystatin C With Regard to Therapeutic Digoxin Monitoring1

“…As a result, we may presume that in all cases, the steady state for digoxin had been reached, even taking into account the high variability in renal function, with a GFR range of approximately 5 to 130 mL/min. The results found for our patients for the simple correlation between the serum concentrations of digoxin, creatinine, and cystatin C are similar to those previously described by Hallberg et al 24 Similarly, the partial correlation analysis, carried out to reduce the possible masking effect of the digoxin dose and the highly significant correlation between the serum concentrations of creatinine and cystatin C, completes the study carried out by these authors and confirms their hypothesis.…”

“…29 O'Riordan et al, 23 in a study with 22 healthy volunteers, did not find any significant correlation for digoxin clearance with the serum concentrations of creatinine or cystatin C but did with creatinine clearance; as a result, these authors concluded that serum cystatin does not have any advantages over serum creatinine in predicting digoxin clearance. 23 In turn, Hallberg et al, 24 using a group of 149 patients on therapeutic digoxin monitoring, found a higher correlation for serum concentrations of digoxin with those of cystatin C than with those of creatinine, particularly in cases in which the steady state had been reached. These authors concluded that improved GFR monitoring, using serum cystatin C as a substitute for serum creatinine, may be considered for better control of digoxin concentrations.…”

Augmented Renal Clearance Implies a Need for Increased Amoxicillin-Clavulanic Acid Dosing in Critically Ill Children

“…Second, it has been shown that CysC is a good renal biomarker in children with sepsis (28) and that CysC-based GFR estimations remain accurate in children presenting with hyperfiltration (in contrast to Scr-based formulae) (24). Finally, CysC was found to better predict elimination of renally excreted drugs in adults compared to Scr or CrCL (29)(30)(31)(32). This is only the second report to identify this new biomarker as a predictor of renal drug clearance in children at the expense of Scr or CrCL (33).…”

Cystatin C: current position and future prospects

“…It concluded that this new parameter was not superior to creatinine in predicting drug clearance. However, these results were rapidly refuted (261) and two studies based on population pharmacokinetics methodology, the most robust in this field, definitively demonstrated the utility of CysC in predicting the clearance of drugs which were eliminated either exclusively or only partially by the kidneys, i.e., two cytotoxic agents, topotecan (262) and carboplatin (263). Interestingly, both of these studies showed an advantage of combining CysC with creatinine rather than using either individually.…”