Estimation of glomerular filtration

Abstract

Glomerular Filtration Rate is used for: Detection (diagnosis and prevalence), Assessment (progression of kidney disease, complications and cardiovascular risk), Management (treatments, onset of renal substitutive therapy, medications and procedures). There are invasive procedures to meet accuracy but unusable in everyday medicine. The equations for estimating glomerular filtration rate using some demographic or anthropometric and also the dosage of blood creatinine or cystatin. These substances should be tested with calibrated and standardized techniques. The equations more used are Counahan-Barrat (pediatrics), Grubb Bjork, Cockcroft Gault, the MDRD-4 and MDRDIDMS, Quadratic Rule and the promise of CKDEPI. All of them have individuals biases, particularly underestimatión in high levels of glomerular filtration rate and up estimation at more reduced levels of renal function. For the large number of samples used, since they had standardized and calibrated dosages, to be developed by experts at several universities and as the equation obtained varies according to the characteristics of the patient. Because it has a mathematical property “spline” is estimated that CKD- EPI has lower biases than shown by the above mentioned. The estimation equations many times must be corroborated by indisputable measurement procedures in patients but instead are very valuable for epidemiological studies or demographic and health registers.