Why 24-h urine albumin excretion rate method still is used for screening of diabetic nephropathy in Isfahan laboratories?

The first step in diagnosis of diabetic nephropathy is measurement of albumin in a spot urine sample. The aim of this study was assessment of the accuracy of urinary albumin to creatinine ratio [UACR] in random urine specimens [RUS] for microalbuminuria and macroalbuminuria screening in Iranian diabetic patients. A total of 200 diabetic patients participated to our study. 24 h timed urine specimens followed by RUS were collected. 24-h urine albumin excretion [24-h urinary albumin excretion [UAE]] and UACR in RUS were measured. Data were analyzed by Pearson's correlation, receiver operating characteristic [ROC] curve and McNemar test. A total of 165 patients finalized the study. Pearson's correlation of coefficient for 24-h UAE versus UACR was 0.64. The area under ROC curve for UACR was 0.83 in microalbuminuria and 0.91 in macroalbuminuria. The cutoff point of 30 mg/g in UACR method had 86% sensitivity and 60% specificity for microalbuminuria screening and cut-off point of 300 mg/g had 75% sensitivity and 99% specificity for macroalbuminuria screening respectively. UACR in RUS showed acceptable performance as a screening test for diagnosis of both micro and macroalbuminuria in Iranian diabetic patients