Veyrat Béatrice, Tosetti François, Morin Jean-François, Moineau Marie-Pierre, Piedimonte Andrée, Clément Patrice, Dreux Sophie, Muller Françoise
LBM Médilys, Lons-le-Saunier, France.
LBM Oriade-Noviale, Meylan, France.
Ann Biol Clin (Paris). 2017 Apr 1;75(2):158-166. doi: 10.1684/abc.2017.1230.
Down syndrome maternal serum marker screening is based on a risk calculation including the free β - human chorionic gonadotropin (hCGβ) and pregnancy-associated placenta protein type A (PAPP-A). The aim of this study was to define the pre-analytical conditions of stability of these markers both in whole blood at 15-25 ̊C and, after centrifugation, in serum at 4-8 ̊C. 158 patients were included in the study. Two automated workstations were used for assays, Cobas 8000e602, Roche Diagnostics (58 patients tested) and DELFIAXpress, PerkinElmer (100 patients tested). The stability of markers was studied in whole blood (15-25 ̊C) 2, 4, 6 and 8 hours after sampling and in serum stored after centrifugation at 4-8 ̊C at 24, 72 and 120 hours. Variations were defined by (C - C)/C, C being the marker concentration at 2 hours and C the concentration at time T. In whole blood kept for 8 hours at 15-25 ̊C, hCGβ increased by a mean 2.4%, whereas the mean increase of PAPP-A was < 1%. In the serum kept for 5 days at 4-8̊C, the mean increase of hCGβ was 4.2%, with no change in PAPP-A. The impact of these variations on risk calculation is low. In conclusion, maternal serum can be store 8 hours at 15-25̊C in whole blood and 5 days at 4-8̊C after centrifugation and serum separation for Down syndrome maternal serum screening.
唐氏综合征孕妇血清标志物筛查基于包括游离β-人绒毛膜促性腺激素（hCGβ）和妊娠相关血浆蛋白A（PAPP-A）的风险计算。本研究的目的是确定这些标志物在15 - 25℃全血中以及离心后在4 - 8℃血清中的分析前稳定性条件。158名患者纳入本研究。使用两个自动化工作站进行检测，即罗氏诊断公司的Cobas 8000 e602（检测58例患者）和珀金埃尔默公司的DELFIA Xpress（检测100例患者）。在采样后2、4、6和8小时研究全血（15 - 25℃）中标志物的稳定性，并在离心后于4 - 8℃储存的血清中在24、72和120小时研究标志物的稳定性。变异由（C - C）/C定义，C为2小时时的标志物浓度，C为时间T时的浓度。在15 - 25℃全血中保存8小时，hCGβ平均增加2.4%，而PAPP-A的平均增加<1%。在4 - 8℃血清中保存5天，hCGβ的平均增加为4.2%，PAPP-A无变化。这些变异对风险计算的影响较小。总之，用于唐氏综合征孕妇血清筛查的孕妇血清在全血中可于15 - 25℃保存8小时，离心和血清分离后在4 - 8℃可保存5天。
