Lutze G, Aumann V, Lutze G, Mittler U
Städtisches Klinikum Magdeburg, Krankenhaus Altstadt, Germany.
Klin Padiatr. 2001 Nov-Dec;213(6):321-4. doi: 10.1055/s-2001-18459.
Without recognition of any inhibitor until now, low concentrations of factor VIII inhibitors (< 1 Bethesda unit (BU)/mL plasma) can be occasionally measured in patients with severe haemophilia A. The existence of so-called "very low" responders is assessed contradictorily due to a methodically caused inhibitor increase. Plasma from 10 patients with severe haemophilia A was incubated with human plasma or animal plasma from pig, cattle, or cat and assayed for factor VIII inhibitors. No signs of inactivation could be detected in five specimen (0 BU/mL plasma). However, measurable signs of factor VIII inactivation (< 1 BU/mL plasma) did occur in the other five. Therefore, the existence of yet not defined unknown inhibitory substances in certain haemophilic plasmas must be assumed. They are directed against human factor VIII as well as partly against animal factor VIII. These "very low" inhibitors are not identical with factor VIII antibodies of "low" and "high" responding haemophiliacs. The clinical importance of "very low" inhibitors is insignificant because they do not tend to increase after exposure to factor VIII. In fact, a effect of factor VIII therapy is the neutralization of this kind of inhibitors.
迄今为止，在未发现任何抑制剂的情况下，重度甲型血友病患者偶尔可检测到低浓度的凝血因子VIII抑制剂（<1贝塞斯达单位（BU）/毫升血浆）。由于方法导致的抑制剂增加，对所谓“极低”反应者的存在评估存在矛盾。将10例重度甲型血友病患者的血浆与人血浆或猪、牛或猫的动物血浆一起孵育，并检测凝血因子VIII抑制剂。在5份样本（0 BU/毫升血浆）中未检测到失活迹象。然而，在其他5份样本中确实出现了可测量的凝血因子VIII失活迹象（<1 BU/毫升血浆）。因此，必须假定某些血友病血浆中存在尚未明确的未知抑制物质。它们既针对人凝血因子VIII，也部分针对动物凝血因子VIII。这些“极低”抑制剂与“低”反应和“高”反应血友病患者的凝血因子VIII抗体不同。“极低”抑制剂的临床重要性不大，因为它们在接触凝血因子VIII后不会趋于增加。事实上，凝血因子VIII治疗的一个作用是中和这类抑制剂。
