Han Minje, Jun Sun-Hee, Song Sang Hoon, Park Kyoung Un, Kim Jin Q, Song Junghan
Department of Laboratory Medicine, Seoul National University Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam, Korea.
Korean J Lab Med. 2011 Oct;31(4):250-6. doi: 10.3343/kjlm.2011.31.4.250. Epub 2011 Oct 3.
We evaluated the performance of multiplex tandem mass spectrometry (MS/MS) in newborn screening for detection of 6 lysosomal storage disorders (LSDs), namely, Niemann-Pick A/B, Krabbe, Gaucher, Fabry, and Pompe diseases and Hurler syndrome.
We revised the conditions and procedures of multiplex enzyme assay for the MS/MS analysis and determined the precision of our enzyme assay and the effects of sample amounts and incubation time on the results. We also measured the degree of correlation between the enzyme activities in the dried blood spots (DBSs) and those in the leukocytes. DBSs of 211 normal newborns and 13 newborns with various LSDs were analyzed using our revised methods.
The intra- and inter-assay precisions were 2.9-18.7% and 8.1-18.1%, respectively. The amount of product obtained was proportional to the DBS eluate volume, but a slight flattening was observed in the product vs. sample volume curve at higher sample volumes. For each enzyme assay, the amount of product obtained increased linearly with the incubation period (range, 0-24 hr). Passing and Bablok regression analysis revealed that the enzyme activities in the DBSs and those in the leukocytes were favorably correlated. The enzyme activities measured in the DBSs were consistently lower in patients with LSDs than in normal newborns.
The performance of our revised techniques for MS/MS detection and enzyme assays was of the generally acceptable standard. To our knowledge, this is the first report on the use of MS/MS for newborn screening of LSDs in an Asian population.
我们评估了多重串联质谱法（MS/MS）在新生儿筛查中检测6种溶酶体贮积症（LSDs）的性能，这6种疾病分别为尼曼-匹克病A/B型、克拉伯病、戈谢病、法布里病、庞贝病和Hurler综合征。
我们修订了用于MS/MS分析的多重酶测定的条件和程序，确定了酶测定的精密度以及样本量和孵育时间对结果的影响。我们还测量了干血斑（DBSs）和白细胞中酶活性之间的相关程度。使用我们修订后的方法对211名正常新生儿和13名患有各种LSDs的新生儿的DBSs进行了分析。
批内和批间精密度分别为2.9%-18.7%和8.1%-18.1%。获得的产物量与DBS洗脱液体积成正比，但在较高样本量时，产物与样本体积曲线出现轻微平缓。对于每种酶测定，获得的产物量随孵育时间（范围为0-24小时）呈线性增加。Passing和Bablok回归分析显示，DBSs和白细胞中的酶活性呈良好相关。LSDs患者DBSs中测得的酶活性始终低于正常新生儿。
我们修订后的MS/MS检测和酶测定技术的性能达到了普遍可接受的标准。据我们所知，这是关于在亚洲人群中使用MS/MS进行LSDs新生儿筛查的首份报告。
