Single-Void Urine Samples Can Be Used To Estimate Quantitative Microalbuminuria

Abstract

The excretion of small quantities of urinary albumin (microalbuminuria) may predict renal failure in diabetes. The measurement of microalbuminuria with radioimmunoassays has been based on 24-h, overnight, and 3- to 4-h collections. To determine whether single-void urine samples can be used to estimate 24-h excretion, we compared the results of 24-h outpatient urine collections with single-void samples corrected for creatinine from diabetic and nondiabetic subjects. The overall correlation of single-void sample results expressed as microgram albumin per milligram creatinine with 24-h excretion (mg/24 h) was excellent (r = .82, P < .001). More important, in the diabetic patients the sensitivity and specificity of detecting 24-h microalbuminuria in the abnormal range were at least 94 and 96%, respectively. Single-void urine specimens adjusted for creatinine discriminate between normal and abnormal levels of microalbuminuria, as determined in 24-h urine collection, with high specificity and sensitivity.