Cystatin C-A novel marker of glomerular filtration rate: A review.

Glomerular filtration rate is routinely assessed by measuring the serum markers such as urea nitrogen and serum creatinine. Although these markers are widely used to assess renal function but they do not perform optimally in certain clinical settings. There is thus a practical need for an easily automated alternative to plasma creatine, which would be more specific, sensitive and reliable from the analytical and clinical view point. Compared with the above endogenous markers, and time consuming laborious tests, Cystatin C facilitates the recognition of abnormal renal function in children, as its reference range is constant beyond the 1(st) year of life. This review mainly focuses on the diagnostic performance of Cystatin C against other renal markers in the pediatric population and in specific subpopulations of patients.