Deproteinization of serum: Another best approach to eliminate all forms of bilirubin interference on serum creatinine by the kinetic Jaffe reaction

Abstract

The negative interference of conjugated, unconjugated, and delta bilirubin on patient serum creatinine determined by the kinetic Jaffe reaction is the unresolved problem. We compared bilirubin interference on thirty patients' serum creatinine obtained from four analyzers, with and without deprotenization before the Jaffe reaction, to the Vitros dry enzymatic method. We found significant negative interference from bilirubin on serum creatinine in all samples directly applied to four wet chemical methods, except the one incorporated with serum blank rate. The negative interferences linearly related to bilirubin concentration. However, bilirubin did not interfere on serum creatinine obtained from all wet chemical methods incorporated with deproteinization process before the reaction. We conclude that deproteinized serum before the reaction is the best approach to eliminate all forms of bilirubin interference on serum creatinine determined by the kinetic Jaffe reaction.

Exogenous interferences with Jaffe creatinine assays: addition of sodium dodecyl sulfate to reagent eliminates bilirubin and total protein interference with Jaffe methods

“…Different laboratory methods are used to overcome the problem of bilirubin interference with creatinine measurement (16)(17)(18)(19)(20)(21)(22). Apart from the addition of potassium ferricyanide, SDS was incorporated in our modified reagent and showed improvement in the specificity of Jaffe reaction.…”

“…Apart from reducing the effect of protein interference, this technique also removed protein-bound interfering substances such as bilirubin. Our previous study (16) demonstrated that deproteinization of sample prior to analysis was the best approach to eliminate bilirubin for serum creatinine by the kinetic Jaffe reaction.…”

“…The deproteinization of patient sera was performed using trichloroacetic acid at the final concentration of 0.37 mol/l (16). Apart from reducing the effect of protein interference, this technique also removed protein-bound interfering substances such as bilirubin.…”

“…Several approaches have been used to minimize nonspecific interferences, such as deproteinization for eliminating the pseudo-chromogen effect of protein (16), early read reaction times (17), addition of some chemicals in reagent systems (18,19), rate-blanking measurement (20), higher temperatures (21), or use of single value compensation for noncreatinine Jaffe reacting chromogens (22). Using the enzymatic creatinine assays, although often recommended as the method of choice, they can have their own interference problems (23).…”

Renal Dysfunction in Liver Transplant Candidates: Evaluation, Classification and Management in Contemporary Practice

“…Techniques have been developed to minimize this interference but are not widespread [30,31]. As a result, serum creatinine and creatininebased equations tend to overestimate the GFR in cirrhotic patients [32][33][34].…”