Evaluation of Urinary Albumin/Creatinine Ratio Strip Assay: A Reliable Screening Alternative to Replacing the Quantitative Biochemical Methods.

Background: Clinical laboratories play a crucial role in the diagnosis and monitoring of chronic kidney disease. Quantitative measurement of urinary albumin, expressed as the albumin/creatinine ratio (ACR), is the most commonly used biomarker for this purpose. This study evaluates the feasibility of using urinary strips as a screening tool for ACR, compared with conventional biochemical methods. Specifically, we assessed the diagnostic performance of the urinary strip and the potential economic impact of implementing this screening approach. Materials and methods: This study included 1,257 samples obtained in primary care, with systematic assessment of requests for urinary strip tests and biochemical quantification of urinary albumin and creatinine. Semiquantitative measurements were performed using Unamax autoanalyzer and quantitative determinations were conducted using AU5800 autoanalyzer. Diagnostic indicators for ACR were calculated for different albumin and creatinine levels. Economic effects were analyzed based on the costs of both testing methods. Results: Results at different cut-off values for albumin and creatinine showed optimal performance at 10 mg/L and above 100 mg/dL, respectively. 666 biochemical quantification tests (53.85% screening) for urinary albumin and creatinine could have been avoided during the study period, resulting in total savings of 522.81€. Conclusions: The present study supports the use of Unamax autoanalyzer for ACR measurement as a screening tool, avoiding unnecessary quantitative measurement, as well as allowing early identification of patients with pathological albuminuria levels. The economic impact was significant, demonstrating effective optimisation of financial resources and workflow efficiency in clinical laboratories.