Serum Creatinine Assay: Enzymatic vs Kinetic Jaffe's Method

Abstract

BACKGROUND: An enzymatic kit method for the determination of serum creatinine was optimized for use with OLYMPUS AU 400 Auto analyzer and its performance characteristics and practicability compared with kinetic Jaffe-based method. Effects of some common interfering substances like glucose and bilirubin on the kinetic Jaffe's and the enzymatic methods were compared. Method comparison between the enzymatic creatinine method (y) and Jaffe's kinetic method (x) gave the following equation for the normal group: y=0.97*x+0.0 and a coefficient correlation R of 0.98.There was very good agreement between both the methods as intra class correlation coefficient (ICC) was between 0.81-1.In the presence of high levels of glucose or bilirubin, the coefficient correlation values were 0.99 and 0.89respectively.

Coagulase negative staphylococcal sepsis in neonates: do we need to adapt vancomycin dose or target?

“…The following data were collected: demographic parameters (gestational age [GA] and PNA, postmenstrual age (PMA), birth- and current weight [BW and CW], gender), therapeutic interventions during vancomycin treatment (mode of ventilation, presence and removal of indwelling catheters and vasoactive treatment), creatinine concentrations (measured by Jaffe kinetic method) at ±72 h of TDM time and reasons for vancomycin treatment, classified as culture proven Gram-positive sepsis, clinical sepsis and no Gram-positive sepsis [18]. Sepsis was considered culture proven if the patient had a Gram-positive pathogen isolated from blood and vancomycin treatment was given for at least 72 h; and clinical sepsis if blood culture was negative but the patient had clinical signs/symptoms suggestive of sepsis and vancomycin treatment was given for at least 72 h. All remaining cases were categorised as no Gram-positive sepsis.…”

A narrative review on laboratory investigations of serum creatinine and solutions to problems therein

“…Different methods have been used to estimate serum creatinine such as isotope dilution mass spectrometry method [10][11][12], HPLC method [13][14][15], creatinase enzymatic method [16,17], and Jaffe reaction method [16][17][18]. Out of all the methods, creatinase enzymatic method and Jaffe reaction methods have been used in clinical settings [16][17][18] while the HPLC and mass spectroscopic methods are used mainly for research purposes [13].…”

“…It is a more frequently used technique in serum creatinine determinations and is more specific [16]. This enzymatic assay for creatinine involves a series of coupled enzymatic reactions including creatininase enzymatic conversion of creatinine into the product creatine which is converted to sarcosine by creatine amidinohydrolase (creatinase) followed by oxidation of sarcosine by sarcosine oxidase producing hydrogen peroxide [17]. The concentration of hydrogen peroxide produced is then measured spectrophotometrically.…”

“…It does not interfere with glucose, acetoacetate and cefoxitin. However, bilirubin has been reported to cause a slight negative interference which depends on the bilirubin and creatinine concentrations [17]. This problem has been largely overcome in the current assays, which uses a more efficient hydrogen peroxide acceptor triiodo-hydroxy-benzoic acid and includes potassium ferrocyanide and detergents to reduce bilirubin interference further [11].…”

Misinterpretation of Chronic Kidney Disease (CKD) staging in patients with diabetes: creatinine estimation method as a source of error

“…This method can be positively and negatively interfered by many substances present in the serum, and common interfering substances include glucose, acetoacetate, bilirubin and cefoxitin [3,4,5]. The enzymatic method has advantages such as being free of interfering substances commonly present in serum and the small sample volume required for testing [6]. Currently, most routine serum creatinine assays are based on kinetic Jaffe method, due to its simplicity and low cost.…”