Diagnostic accuracy of the urinary albumin: creatinine ratio determined by the CLINITEK Microalbumin and DCA 2000+ for the rule-out of albuminuria in chronic kidney disease.
An increased urinary albumin excretion (albuminuria) is an established test for the early detection of renal disease and is also recognized as a risk factor for cardiovascular disease and mortality in a number of clinical settings. There is an established body of data which shows that a random urinary albumin:creatinine ratio (ACR) based on a random urine sample correlates well with 24-hour urinary albumin excretion measurement. However, there is little data to show whether specific point-of-care testing devices can be used to rule-in or rule-out increased urinary albumin excretion in comparison to a 24-hour urinary albumin excretion measurement. This study evaluated the ability to rule-in or rule-out albuminuria in a cohort of patients attending a renal outpatient clinic, using the urinary ACR determined by the CLINITEK Microalbumin (Siemens Healthcare Diagnostics Inc., Deerfield, US) a semi-quantitative strip test, and by the DCA 2000+ (Siemens Healthcare Diagnostics Inc.) a quantitative cassette based test using 3 random urine samples collected within a 24-hour period compared to 24-hour urinary albumin measurement. The CLINITEK system was shown to be a reliable test for ruling out increased urinary albumin excretion with negative likelihood ratios less than 0.05 above the 24-hour urinary albumin excretion rate of 30 mg/24 h (threshold for microalbuminuria), and less than 0.01 above the albumin excretion rate of 100 mg/24 h. The DCA 2000+ system demonstrated similar performance as a rule-out test, with likelihood ratios of less than 0.02 at 24-hour albumin excretion rates above 30 mg/24 h. Both the CLINITEK and DCA 2000+ systems could be used to rule-out increased urinary albumin excretion at the albumin excretion cut-off rate of 30 mg/24 h in this cohort of patients.
Guy
Mark
M
Department of Clinical Biochemistry, Salford Royal NHS Foundation Trust, Hope Hospital, Stott Lane, Salford, M6 8HD, UK.
Newall
Ronald
R
Borzomato
Joanna
J
Kalra
Philip A
PA
Price
Christopher
C
D000419:Albuminuria / Q000150:complications / Q000175:diagnosis* / Q000652:urine*; D003404:Creatinine / Q000652:urine*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000652:urine*; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors
D011933:Reagent Kits, Diagnostic; D003404:Creatinine