串联质谱检测干血滤纸片中氨基酸质控分析

Analysis of Quality Control Testing Results of Amino Acids by Tandem Mass Spectrometry in Dry Blood Spots

目的通过对近3年的质控结果进行分析,探讨影响检测结果的因素及应对措施。方法美国疾病控制和预防中心(CDC)每年提供4批氨基酸质控干血滤纸片,利用串联质谱技术检测干血滤纸片中氨基酸水平。以美国CDC检测结果为标准,分析本实验室氨基酸质控结果偏差及其他实验室质控结果(213个实验室的均值)偏差之间的差异。结果本实验室每次质控结果所有氨基酸均在美国CDC检测结果95%可信区间内,且每一批结果的临床评价与美国CDC质控临床评价完全一致。本实验室质控结果偏差与其他实验室质控结果偏差比较,苯丙氨酸、亮氨酸、甲硫氨酸、酪氨酸和缬氨酸均无显著性差异,瓜氨酸有显著性差异(Z=-2.945P<0.005)。结论本实验室氨基酸质控结果,达到美国CDC的质控要求,瓜氨酸检测值偏低,其阳性判断切割值设定也相应降低。

Objective Tandem mass spectrometry is a new technology applied in clinical testing in the last few years. This technology can detect dozens of amino acids and acylcarnitines rapidly. To investigate the factors that affect the testing results and analyze the quality control resuits of our lab in last 3 years. Methods The dried blood filter papers were provided by Centers of Disease Control（CDC） of United States. The levels of amino acids in the dried blood filter papers were tested by tandem mass spectrometry. The deviations of the amino acids levels of our laboratory and other laboratories to those of CDC of United States were compared. Results All the amino acid levels in our laboratory were with in 95% confidence interval of the results CDC of United States, and the clinical evaluation of the results from our laboratory and CDC of United States were consistent. By comparing the deviations between our laboratory and CDC, and deviations between other laboratories and CDC, the levels of phenylalanine,leucine, methionine, tyrosine and valine were no significant difference, but the level of citrulline was significant different （Z = - 2. 945 P 〈 0. 005 ）. Conclusions The results of amino acid quality control of our laboratory achieve the requirements of CDC of United States. Citrulline detection value is low in our laboratory, and its cut- off value shall be reduced accordingly.