Owaidah Tarek M, Alzahrani Hazzaa A, Al-Numair Nouf S, Alnosair Abdulmjeed O, Aguilos Amelita M, Saleh Mahasen
Departments of Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
Departments of Oncology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
Adv Hematol. 2020 Sep 9;2020:8768074. doi: 10.1155/2020/8768074. eCollection 2020.
The one-stage assay is the most common method to measure factor VIII activity (FVIII : C) in hemophilia A patients. The chromogenic assay is another two-stage test involving purified coagulation factors followed by factor Xa-specific chromogenic substrate.
This study aimed to assess the discrepancy and correlation between the chromogenic and one-stage assays in measuring FVIII : C levels in hemophilia patients receiving Extended Half-Life Elocta® as a recombinant extended half-life coagulation factor.
We performed a study comparing the measurements of FVIII : C levels by the chromogenic versus the one-stage assays at different drug levels. Data of FVIII : C levels, dosage, and the time interval from administration to measurement were retrieved from the hospital records. The correlation, mean differences, and discrepancy between the two assays were calculated. The linear regression analysis was used to predict the time interval till reaching 1% FVIII : C.
Fourteen patients with 56 samples were included in the study. Of them, 13 patients were receiving Elocta® as a prophylactic, while one was receiving Elocta® on demand. One-third of these samples showed a discrepancy between the chromogenic and one-stage assays. The two assays were well correlated. Mean differences were significant at the individual and the time interval level. The time since the last Elocta® injection could significantly predict FVIII : C levels ( = 0.366, < 0.001).
Our findings suggested a significant difference between both methods; the FVIII : C levels measured by the one-stage assay were less than those estimated by the chromogenic assay. However, the measurements of FVIII levels by the two assays were well correlated but discrepant in one-third of the samples. The levels of FVIII : C reach 1% after 5.4 days since the last Elocta® administration.
一步法检测是测量甲型血友病患者凝血因子Ⅷ活性（FVIII∶C）最常用的方法。发色底物法是另一种两阶段检测方法，该方法先使用纯化的凝血因子，然后使用Xa因子特异性发色底物。
本研究旨在评估发色底物法和一步法在测量接受重组延长半衰期凝血因子Elocta®（艾美赛珠单抗）治疗的血友病患者FVIII∶C水平时的差异及相关性。
我们开展了一项研究，比较发色底物法和一步法在不同药物水平下对FVIII∶C水平的检测结果。从医院记录中获取FVIII∶C水平、剂量以及给药至检测的时间间隔数据。计算两种检测方法之间的相关性、平均差异和偏差。采用线性回归分析预测达到1% FVIII∶C所需的时间间隔。
本研究纳入了14例患者的56份样本。其中，13例患者接受Elocta®预防性治疗，1例患者按需接受Elocta®治疗。这些样本中有三分之一在发色底物法和一步法检测结果上存在偏差。两种检测方法相关性良好。个体水平和时间间隔水平的平均差异均具有统计学意义。距上次注射Elocta®的时间能够显著预测FVIII∶C水平（r = 0.366，P < 0.001）。
我们的研究结果表明两种方法存在显著差异；一步法检测的FVIII∶C水平低于发色底物法估计的水平。然而，两种检测方法对FVIII水平的测量相关性良好，但三分之一的样本存在偏差。末次注射Elocta®后5.4天FVIII∶C水平达到1%。
