METHODS: Residual body fluids from clinically ordered testing were mixed (<10% by volume) with stock solutions of interferent (spiked) and compared with a control spiked with an equal volume of 0.9% saline. The analytes were measured on the Roche cobas c501 instrument. Difference and percentage difference were calculated and compared with allowable total error limits. A subset of samples were serially diluted with 0.9% saline. Mean (SD) difference and percentage difference were calculated.
RESULTS: The interference thresholds were lower than the package insert for lactate dehydrogenase, cholesterol, triglycerides, and total protein for hemolysis; amylase, cholesterol, and total protein for icterus; and albumin for lipemia. Only cholesterol and triglyceride results returned to baseline upon dilution of icteric samples.
CONCLUSIONS: Interference thresholds in body fluids were lower than blood for 6 analytes. Diluting interferences that surpass these limits does not produce reliable results that are comparable to the baseline results before spiking in the interferent.
方法:将来自临床订购测试的残余体液与干扰物(加标)的储备溶液混合(<10%体积),并与用等体积的0.9%盐水加标的对照进行比较。在Rochecobasc501仪器上测量分析物。计算差异和百分比差异,并与允许的总误差极限进行比较。用0.9%盐水连续稀释样品的子集。计算平均值(SD)差异和百分比差异。
结果:干扰阈值低于乳酸脱氢酶的包装说明书,胆固醇,甘油三酯,和溶血总蛋白;淀粉酶,胆固醇,黄疸的总蛋白和脂血的白蛋白。只有胆固醇和甘油三酯的结果在黄疸样品稀释后返回基线。
结论:6种分析物的体液干扰阈值低于血液。超过这些限制的稀释干扰不会产生与干扰物尖峰之前的基线结果相当的可靠结果。