[Microalbuminuria screening in diabetics].

Nocturnal albumin excretion rate was measured in 133 diabetics and the results were compared with those in first morning urine and urine spontaneously voided later in the morning. Albumin concentrations greater than 20 mg/l in the first morning urine indicated a raised albumin excretion rate of 20-200 micrograms/min (sensitivity 86%, specificity 98%). Simultaneous creatinine measurement and calculation of the albumin/creatinine ratio did not increase sensitivity or specificity. An albumin concentration greater than 20 mg/l in spontaneously voided day urine pointed to a raised albumin excretion rate (sensitivity 90%, specificity 60%). These results suggest that determining the albumin concentration in the first voided morning urine is suitable as screening test for microalbuminuria.