Evaluation of the Lipid Interference for Siemens BN ProSpec Cystatin C Assay Using Pediatric Samples

Endogenous interferents (lipids, hemoglobin and bilirubin) are a common cause of pre-analytical laboratory errors. We evaluated the effect of lipemia on Siemens cystatin C assay using pediatric samples. Lipemic samples were prepared by adding various concentrations of triglycerides into low and high cystatin C sample pools. Cystatin C concentrations were then measured on Siemens BN ProSpec analyzer and change of the analyte concentrations was determined. Low and high cystatin C sample pools were not affected by additions of lower lipid concentrations (150, 500 and 750 mg/dL), while the negative bias of <10% was seen with additions of higher lipid concentrations (1000 and 1500 mg/dL). Our results suggest that the BN ProSpec assay is a good alternative for cystatin C measurements in our pediatric population with no major interference from lipemia.