Evaluation the diagnostic accuracy of albuminuria detection in semi-quantitative urinalysis

Background Taiwan has the highest end-stage renal disease prevalence in the world, and the costs on the maintenance of dialysis imposes a great financial burden on National Health Insurance. Routine urinalysis provides an opportunity for the early detection of microalbuminuria. We evaluated the accuracy of semi-quantitative chemical methods from Siemens Novus Pro12 dipstick for albumin-creatinine ratio (ACR). Methods We collected 1029 random urine samples and performed urinary analytic tests by Siemens Novus with Pro12 dipsticks and also calculated the urinary ACR. The reference method was performed by Hitachi LST008, a quantitative assay. The percentage of exact agreement in ACR was 81.9% between Siemens Novus and Hitachi LST008. The percentage of agreement within 1 level between the 2 methods was 98.5%. When ACR > 30 mg/g was defined as the threshold for positive results, the sensitivity, specificity, positive, and negative predictive values for microalbuminuria were 87.2%, 91.6%, 91.5%, and 87.3%, respectively. There were 778 cases with negative results of urinary protein, analyzed by conventional dipsticks. 149 of 778 (19.2%) cases were positive, measured by Pro12 dipsticks, and 111 of 149 (74.5%) cases were confirmed positive ACR by Hitachi LST008. Conclusions Urinary ACR measured by Siemens Novus with Pro12 dipsticks was shown to be a reliable test for detection of microalbuminuria.