Lloyd, M.M., Department of Chemical Pathology, University of Free State, South Africa; Kuyl, J., Department of Chemical Pathology, University of Free State, South Africa; van Jaarsveld, H., Department of Chemical Pathology, University of Free State, South Africa
Background: Microalbuminuria, the presence of low levels of albumin in the urine, indicates renal damage and is recognised as a risk factor for the progression of renal and cardiovascular disease. Several international scientific bodies recommend microalbuminuria screening. Point-of-care testing (POCT) of microalbuminuria allows immediate identification of risk, and monitoring of treatment effects. In this study, two POCT instruments were evaluated as microalbuminuria screening methods. Method: Spot urine specimens from diabetic patients were analysed with the quantitative HemoCue® urine albumin analyser (n = 245), and the semiquantitative Clinitek® microalbumin urine dipstick (n = 204). These results were compared to the respective data for laboratory-determined albumin (nephelometry), creatinine (modified Jaffe) and albumin-to-creatinine ratio (ACR). Results: Linear regression analysis demonstrated a good correlation for the HemoCue® urine albumin with the laboratorydetermined albumin concentration (y = 0.8557x + 0.2487y, r = 0.97). The sensitivities for the HemoCue® and Clinitek® POCT systems were 79.6% and 83.8%, and the specificities 97.1% and 93.8% respectively. Positive and negative predictive values for the HemoCue® were 95.6% and 85.8%, and were 88.6% and 91.0% the Clinitek®. The repeatability of both instruments was excellent. Both instruments are easy to use, and more cost-effective than the laboratory methods for albumin and ACR. Conclusion: Both the HemoCue® and the Clinitek® microalbumin POCT systems for albuminuria are easy to use and inexpensive, and are adequately accurate as a screening method. Although the HemoCue® POCT system measures only urine albumin concentration, its sensitivity and specificity compared well with that of the Clinitek® POCT system, which determines the ACR. © SAFP.
article; controlled study; creatinine urine level; device; diabetic patient; diagnostic accuracy; diagnostic test accuracy study; human; laboratory test; microalbuminuria; nephelometry; point of care testing; predictive value; quantitative analysis; risk assessment; risk factor; screening test; sensitivity and specificity