Particle enhanced turbidimetric immunoassay (PETIA)

The Cystatin C kit from BÜHLMANN provides liquid, ready to use reagents offering a maximum convenience and accuracy. The calibrator and controls are included in the kits and CE-marked applications are available upon request. Due to the use of avian antibodies no interference through rheumatic factors are detectable.


Glomerular filtration rate (GFR)

Many studies confirmed that Cystatin C is a reliable marker for Glomerular filtration rate (GFR) assessment. 3 µl of blood sample are required to run the BÜHLMANN Cystatin C assay on routine clinical analysers.

Various methods based on Creatinine are being widely used to assess the GFR. However, all of them often lead to over or under estimation of the GFR and thus has to be adjusted by various factors including age, gender, diet, muscle mass and race. Unlike creatinine serum Cystatin C is virtually unaffected by these factors and very simple formulas can be used to obtain a reliably estimated GFR.

A number of well documented studies comparing creatinine or creatinine based GFR estimations and Cystatin C have shown Cystatin C to be superior to creatinine. In particular, creatinine based assesments of GFR have a lack of sensitivity until stage 2 and 3 of renal disease. Cystatin C does not have this “blind area”, thus GFR changes can be detected earlier when intervention might improve outcomes. Cystatin C values are already elevated when creatinine is still within the normal range.

A Cystatin C based GFR calculation can directly be performed on

For further information see Dossier: Chronic Kidney Disease


CYSTATIN Product Information

Method PETIA
Time to Result 10 min (approx.)
Sample Type 2 µl plasma, serum
Sensitivity 0.25-8.0 mg/ml
Dynamic Range 0.33 mg/ml
Order Code KK-CYC