Semi-quantitative determination of microalbuminuria by urinary dipstick.
Microalbuminuria predicts subsequent clinical nephropathy and mortality in diabetic patients. This study was undertaken to determine the usefulness of a new immunochemical urinary dipstick test (Micral-Test, Boehringer Mannheim, GmbH Mannheim, Germany) in identifying urinary albumin concentrations within the microalbuminuric range (urinary albumin concentration 20-200 mg/L). Twenty-four hour urine specimens were collected from 298 consecutive diabetic outpatients. Micral-Test was performed by two laboratory scientists blinded to each other's results and those of radioimmunoassay (RIA) and immunoturbidimetry on the same specimen. When compared with RIA, Micral-Test had an overall sensitivity of 92.2%, specificity of 92.3% and positive predictive value of 86.4%. However, at the threshold value of 20 mg/1 Micral-Test showed false positive results in 37.8% of samples when compared with RIA. Similar results were obtained when Micral-Test was compared with immunoturbidimetry. We conclude that Micral-Test is a useful screening method for the detection of microalbuminuria. We suggest that positive tests be confirmed by a timed urine collection using established methodology and that patients whose Micral-Test is negative be subjected to annual retesting.
Gilbert
R E
RE
Endocrinology Unit, Austin Hospital, Heidelberg, Vic., Australia.
Akdeniz
A
A
Jerums
G
G
D000419:Albuminuria / Q000175:diagnosis* / Q000652:urine; D048909:Diabetes Complications; D005189:False Positive Reactions; D006801:Humans; D007120:Immunochemistry / Q000379:methods; D009391:Nephelometry and Turbidimetry; D011237:Predictive Value of Tests; D011863:Radioimmunoassay; D011934:Reagent Strips
D011934:Reagent Strips