Guy Mark, Newall Ronald, Borzomato Joanna, Kalra Philip A, Price Christopher
Department of Clinical Biochemistry, Salford Royal NHS Foundation Trust, Hope Hospital, Stott Lane, Salford, M6 8HD, UK.
Clin Chim Acta. 2009 Jan;399(1-2):54-8. doi: 10.1016/j.cca.2008.09.006. Epub 2008 Sep 14.
An increased urinary albumin excretion (albuminuria) is an established test for the early detection of renal disease and is also recognized as a risk factor for cardiovascular disease and mortality in a number of clinical settings. There is an established body of data which shows that a random urinary albumin:creatinine ratio (ACR) based on a random urine sample correlates well with 24-hour urinary albumin excretion measurement. However, there is little data to show whether specific point-of-care testing devices can be used to rule-in or rule-out increased urinary albumin excretion in comparison to a 24-hour urinary albumin excretion measurement. This study evaluated the ability to rule-in or rule-out albuminuria in a cohort of patients attending a renal outpatient clinic, using the urinary ACR determined by the CLINITEK Microalbumin (Siemens Healthcare Diagnostics Inc., Deerfield, US) a semi-quantitative strip test, and by the DCA 2000+ (Siemens Healthcare Diagnostics Inc.) a quantitative cassette based test using 3 random urine samples collected within a 24-hour period compared to 24-hour urinary albumin measurement. The CLINITEK system was shown to be a reliable test for ruling out increased urinary albumin excretion with negative likelihood ratios less than 0.05 above the 24-hour urinary albumin excretion rate of 30 mg/24 h (threshold for microalbuminuria), and less than 0.01 above the albumin excretion rate of 100 mg/24 h. The DCA 2000+ system demonstrated similar performance as a rule-out test, with likelihood ratios of less than 0.02 at 24-hour albumin excretion rates above 30 mg/24 h. Both the CLINITEK and DCA 2000+ systems could be used to rule-out increased urinary albumin excretion at the albumin excretion cut-off rate of 30 mg/24 h in this cohort of patients.
尿白蛋白排泄增加（蛋白尿）是早期检测肾脏疾病的一项既定检测方法，在许多临床情况下也被认为是心血管疾病和死亡的危险因素。已有大量数据表明，基于随机尿样的随机尿白蛋白：肌酐比值（ACR）与24小时尿白蛋白排泄量测量结果具有良好的相关性。然而，几乎没有数据表明，与24小时尿白蛋白排泄量测量相比，特定的即时检测设备能否用于确诊或排除尿白蛋白排泄增加。本研究评估了在一组肾科门诊患者中确诊或排除蛋白尿的能力，使用CLINITEK微量白蛋白（西门子医疗诊断公司，美国伊利诺伊州迪尔菲尔德）半定量试纸条检测和DCA 2000+（西门子医疗诊断公司）定量盒式检测测定尿ACR，这两种检测均使用在24小时内收集的3份随机尿样，并与24小时尿白蛋白测量结果进行比较。结果显示，CLINITEK系统是排除尿白蛋白排泄增加的可靠检测方法，在24小时尿白蛋白排泄率高于30 mg/2（微量蛋白尿阈值）时，阴性似然比小于0.05；在白蛋白排泄率高于100 mg/24 h时，阴性似然比小于0.01。DCA 2000+系统作为排除性检测表现出类似的性能，在24小时白蛋白排泄率高于30 mg/24 h时，似然比小于0.02。在该组患者中，CLINITEK和DCA 2000+系统均可用于在白蛋白排泄临界率为30 mg/24 h时排除尿白蛋白排泄增加。
