ABSTRACT
BACKGROUND: Monitoring urinary albumin is a useful method in clinical practice for the management of diabetic nephropathy, chronic kidney disease, and hypertension. Currently there are neither standardized methods nor reference material for the determination of urinary albumin; for this reason it is useful to compare different assays used in clinical laboratory. OBJECTIVES: The aim of this study is to verify analytical performance of an immunoturbidimetric assay on Roche Cobas 8000 platform and to compare urinary albumin results with those obtained by immunonephelometry on Siemens Dade Behring BN II Nephelometer. RESULTS: The method comparison showed a good linear relationship, confirmed by Passing-Bablok and Bland-Altman plots. The turbidimetric assay meets the requirements of accuracy and precision for the practice of medical diagnostics and clinical use. CONCLUSIONS: The present study can contribute to the methods standardization and harmonization of urinary albumin assay.
Subject(s)
Albuminuria/diagnosis , Diabetic Nephropathies/urine , Hypertension/urine , Immunoassay/methods , Nephelometry and Turbidimetry/methods , Renal Insufficiency, Chronic/urine , Albuminuria/urine , Humans , Regression AnalysisSubject(s)
Ferritins/blood , Immunoassay/methods , Nephelometry and Turbidimetry/methods , Humans , Linear ModelsABSTRACT
BACKGROUND AND OBJECTIVES: The increased need in clinical chemistry laboratories for methods of homocysteine determination, in correlation with cardiovascular diseases and nutritional deficient status, has led to the development of different analytical methods; fluorescent immunoenzymatic assays and, recently, new fully automated spectrophotometric methods are commercially available. In this paper, we compared data obtained from a new enzymatic method for homocysteine assay (Carolina Liquid Chemistries), with data obtained from a HPLC reference method and an immunoenzymatic method (Abbott AxSYM immunoassay). RESULTS: The enzymatic method shows a good correlation with both the HPLC (Y = -1.3 + 1.02X; R2 = 0.93) and the immunoenzymatic method (Y = 0.7 + 1.02X; R2 = 0.92), although a bias enhancement was present in some samples. However, the enzymatic method shows a superior analytical feasibility because it needs only common laboratory instruments (UV-visible spectrophotometer) and can be easily adapted to large automatic clinical chemistry analyzers. Moreover, it lowers the laboratory cost of the analysis in comparison to both HPLC and immunoenzymatic methods. CONCLUSIONS: The enzymatic Carolina Liquid Chemistries method for homocysteine assay shows acceptable analytical performance and undoubtedly possesses technical and cost advantages.