Revisao bibliografica sobre cistatina C como marcador bioquimico da função renal e sua correlação com outras patologias.

Abstract

Currently the renal disease is a big problem of the public health that affects a large numbers of people in Brazil and in the world. The measure of the renal function is important for the prevention and precocious diagnosis. The marker most widely used to estimate the renal function has been the serum creatinine, however with some limitations. In some conditions the result found of the serum creatinine must be corrected (through the use of formulas which take into consideration the individual own characteristics) to be duly interpreted. Due to various influences involved in the quantification of creatinine the Cystatin C was recently proposed as an endogenous marker of renal function much more sensitive than creatinine, allowing them to observe alterations in glomerular filtrations so precocious than the “clearance” of creatinine. The Cystatin C is an unglycosylated protein of low molecular weight (13,343 kDa), composed of 120 aminoacids, produced by all nucleated cells, belonging to the family of cysteine-proteases, proteolytic enzymes involved in a series of pathological processes. The quantity of Cystatin C produced by the organism is constant, being the concentration peripheral on exclusive dependence of the rhythm of glomerular filtration. The quantification of Cystatin C can be given by the following methods: Nephelometry and Turbidimetry. Besides assessing renal function, the Cystatin C also has been important in the diagnosis of other pathologies and its correlation with these deserves special attention for future works.