Briselli M F, Ellman L
Am J Clin Pathol. 1980 Nov;74(5):677-80. doi: 10.1093/ajcp/74.5.677.
Seven patients who had normal prothrombin times but prolonged activated partial thromboplastin times (aPTT) are described. The prolonged aPTT, obtained with micronized silica as the contact activating agent in a semi-automated optical end-point system, a nonautomated optical end-point system, and a conductivity end-point system, corrected to normal when kaolin was used as the contact activating agent. Abnormal results were also obtained with celite and ellagic acid as contact activating agents. The activities of various clotting factors were within normal limits in all cases where they were assayed. The thromboplastin dilution test was uniformly negative, and mixtures of one patient's plasma with that of another patient failed to correct the abnormal aPTT. No patients had a personal or family history of bleeding, and all underwent surgery without bleeding difficulties. This pattern of a prolonged aPTT that corrects to normal when kaolin is used as the contact activator appears to represent a previously unrecognized laboratory phenomenon.
本文描述了7例凝血酶原时间正常但活化部分凝血活酶时间（aPTT）延长的患者。在半自动光学终点系统、非自动光学终点系统和电导率终点系统中，以微粉化二氧化硅作为接触激活剂时，aPTT延长；而当使用高岭土作为接触激活剂时，aPTT恢复正常。以硅藻土和鞣花酸作为接触激活剂时，也得到了异常结果。在所有检测的病例中，各种凝血因子的活性均在正常范围内。凝血活酶稀释试验均为阴性，且一名患者的血浆与另一名患者的血浆混合后未能纠正异常的aPTT。所有患者均无个人或家族出血史，且均顺利接受了手术，未出现出血困难。当使用高岭土作为接触激活剂时，aPTT延长但恢复正常的这种模式似乎代表了一种此前未被认识到的实验室现象。
