BACKGROUND: The first step in the diagnosis of diabetic nephropathy is to measure albumin in a spot urine sample. The aim of this study was to assess the accuracy of urinary albumin concentration (UAC), urinary albumin-to-creatinine ratio (UACR), and the Micral-Test II in a random urine specimen (RUS) for microalbuminuria screening in diabetes mellitus. METHODS: Two hundred and seventy-eight patients collected 24 h timed urine specimens followed by RUS. Albumin (immunoturbidimetry) and creatinine were measured in protein-negative (Combur-Test) urine samples. Samples were classified as normoalbuminuric [24 h urinary albumin excretion rate (UAER) <20 microg/min; n = 189] and microalbuminuric (UAER =20-199 microg/min; n = 89). Micral-Test II readings were performed in 130 RUS. Receiver operating characteristics (ROC) curves were constructed using UAER as the reference standard. RESULTS: The areas under the ROC curves were similar for UAC (0.934+/-0.032) and UACR (0.920+/-0.035; P = 0.626), but the Micral-Test II had lower accuracy to diagnose microalbuminuria (area = 0.846+/-0.047) than UAC (P = 0.014). The first cutoff point with 100% sensitivity for UAC was 14.4 mg/l (specificity =77.2%), and 15.7 mg/g for UACR (specificity =73.0%). Concerning the Micral-Test II, sensitivity and specificity for the 20 mg/l cutoff point were 90.0 and 46.0%, respectively. The agreement between UAER and the Micral-Test II for microalbuminuria diagnosis was 55.8% (kappa = 0.22; P < 0.001). The cost of diagnosing microalbuminuria was 1.74 dollars(UAC), 2.00 dollars (UACR) and 4.09 dollars (Micral-Test II) per patient. CONCLUSIONS: Measurement of UAC in a RUS was the best choice for the diagnosis screening of microalbuminuria in diabetic patients, considering cost and accuracy.
BACKGROUND: The first step in the diagnosis of diabetic nephropathy is to measure albumin in a spot urine sample. The aim of this study was to assess the accuracy of urinary albumin concentration (UAC), urinary albumin-to-creatinine ratio (UACR), and the Micral-Test II in a random urine specimen (RUS) for microalbuminuria screening in diabetes mellitus. METHODS: Two hundred and seventy-eight patients collected 24 h timed urine specimens followed by RUS. Albumin (immunoturbidimetry) and creatinine were measured in protein-negative (Combur-Test) urine samples. Samples were classified as normoalbuminuric [24 h urinary albumin excretion rate (UAER) <20 microg/min; n = 189] and microalbuminuric (UAER =20-199 microg/min; n = 89). Micral-Test II readings were performed in 130 RUS. Receiver operating characteristics (ROC) curves were constructed using UAER as the reference standard. RESULTS: The areas under the ROC curves were similar for UAC (0.934+/-0.032) and UACR (0.920+/-0.035; P = 0.626), but the Micral-Test II had lower accuracy to diagnose microalbuminuria (area = 0.846+/-0.047) than UAC (P = 0.014). The first cutoff point with 100% sensitivity for UAC was 14.4 mg/l (specificity =77.2%), and 15.7 mg/g for UACR (specificity =73.0%). Concerning the Micral-Test II, sensitivity and specificity for the 20 mg/l cutoff point were 90.0 and 46.0%, respectively. The agreement between UAER and the Micral-Test II for microalbuminuria diagnosis was 55.8% (kappa = 0.22; P < 0.001). The cost of diagnosing microalbuminuria was 1.74 dollars(UAC), 2.00 dollars (UACR) and 4.09 dollars (Micral-Test II) per patient. CONCLUSIONS: Measurement of UAC in a RUS was the best choice for the diagnosis screening of microalbuminuria in diabeticpatients, considering cost and accuracy.
Authors: Elsbeth C Witte; Hiddo J Lambers Heerspink; Dick de Zeeuw; Stephan J L Bakker; Paul E de Jong; Ronald Gansevoort Journal: J Am Soc Nephrol Date: 2008-12-17 Impact factor: 10.121
Authors: David B Sacks; Mark Arnold; George L Bakris; David E Bruns; Andrea Rita Horvath; M Sue Kirkman; Ake Lernmark; Boyd E Metzger; David M Nathan Journal: Diabetes Care Date: 2011-06 Impact factor: 19.112
Authors: Vilas U Chavan; Pushpa P Durgawale; Anjum K Sayyed; Ajit V Sontakke; Nazir R Attar; Swati B Patel; Sangita R Patil; Shreyasprasad D Nilakhe Journal: Indian J Clin Biochem Date: 2011-04-30
Authors: N R Robles; F J Felix; D Fernandez-Berges; J Perez-Castán; M J Zaro; L Lozano; P Alvarez-Palacios; A Garcia-Trigo; V Tejero; Y Morcillo; A B Hidalgo Journal: Int Urol Nephrol Date: 2013-01-26 Impact factor: 2.370