Magid Erik, Guldager Henrik, Hesse Dan, Christiansen Merete Skovdal
Departments of Clinical Biochemistry and Anaesthesiology, Amager Hospital, Copenhagen, Denmark.
Clin Chem. 2005 Nov;51(11):2052-8. doi: 10.1373/clinchem.2005.055442. Epub 2005 Sep 15.
Inflammation-associated proteinuria in acute, nonrenal disease is a common but poorly understood phenomenon. We performed an observational study of the urinary excretion of orosomucoid (alpha(1)-acid glycoprotein), albumin, alpha(1)-microglobulin (protein HC), and IgG to obtain quantitative and temporal data on these 4 proteins.
Urine samples were collected at daily intervals for up to 23 days from 6 patients with surgery-induced inflammation and at hourly intervals for a 24-h period from 7 sepsis patients. Urinary protein concentrations were assessed by immunoturbidimetry.
During surgery-induced inflammation, the increase and decrease in orosomucoid excretion mirrored changes in plasma C-reactive protein. Values for all 4 urinary proteins were increased in sepsis patients. The observed maximum increases in urinary protein excretion relative to the upper reference values were 280-fold for orosomucoid, 98-fold for alpha(1)-microglobulin, 33-fold for albumin, and 26-fold for IgG.
Orosomucoid, usually present in plasma and urine in much lower concentrations than albumin, is increased in urine to concentrations equal to or higher than albumin in proteinuria associated with acute inflammation. The pathophysiologic mechanisms responsible for this markedly increased excretion are unknown. Monitoring of urinary excretion of orosomucoid and other specific proteins, expressed as protein/creatinine ratios, may provide a window for clinically relevant real-time observation of changes in acute inflammatory processes. Orosomucoid in urine may be a more informative marker than albumin for inflammation.
急性非肾性疾病中与炎症相关的蛋白尿是一种常见但了解甚少的现象。我们对血清类黏蛋白（α1-酸性糖蛋白）、白蛋白、α1-微球蛋白（蛋白HC）和IgG的尿排泄情况进行了一项观察性研究，以获取这4种蛋白质的定量和时效性数据。
从6例手术诱发炎症的患者中，每隔1天收集一次尿液样本，最长收集23天；从7例脓毒症患者中，每隔1小时收集一次尿液样本，收集24小时。采用免疫比浊法评估尿蛋白浓度。
在手术诱发炎症期间，血清类黏蛋白排泄的增减反映了血浆C反应蛋白的变化。脓毒症患者的所有4种尿蛋白值均升高。相对于参考上限值，观察到的尿蛋白排泄最大增幅为：血清类黏蛋白280倍、α1-微球蛋白98倍、白蛋白33倍、IgG 26倍。
血清类黏蛋白通常在血浆和尿液中的浓度远低于白蛋白，在与急性炎症相关的蛋白尿中，其尿浓度升高至等于或高于白蛋白的浓度。导致这种排泄显著增加的病理生理机制尚不清楚。监测血清类黏蛋白和其他特定蛋白质的尿排泄情况（以蛋白/肌酐比值表示），可能为临床实时观察急性炎症过程的变化提供一个窗口。尿中的血清类黏蛋白可能是比白蛋白更具信息量的炎症标志物。
