Vun C M, Evans S, Chong B H
Department of Haematology, Prince of Wales Hospital, Sydney, New South Wales, Australia.
Thromb Res. 1996 Mar 1;81(5):525-32. doi: 10.1016/0049-3848(96)00027-8.
Previous studies suggested that the cross-reactivity rates of low molecular weight (LMW) heparins with the antibody in heparin-induced thrombocytopenia (HIT) are more than 80%, whilst that of the LMW heparinoid (Orgaran) is relatively low at about 10%. These earlier studies were limited either in the number of patients studied, or in investigating only a single drug. They were also inadequate due to non-standardisation of testing conditions. This study compares three LMW heparins (Fragmin, Clexane, Fraxiparin) and a heparinoid (Orgaran) in their cross-reactivity rates with the HIT antibody. The sera of 45 HIT patients were tested using platelet aggregometry under standardised conditions. The cross-reactivity rates are: 7% (Orgaran), 89% (Fragmin), 83% (Clexane) and 86% (Fraxiparin). Although there are no controlled trials to determine the in vivo cross-reactivity rates of LMW heparins and heparinoid, the low in vitro cross-reactivity rate of the latter favours its use in HIT. Nevertheless, the therapeutic use of these drugs in HIT should be preceded by exclusion of in vitro cross-reactivity.
以往研究表明，低分子量（LMW）肝素与肝素诱导的血小板减少症（HIT）抗体的交叉反应率超过80%，而低分子量类肝素（奥加诺）的交叉反应率相对较低，约为10%。这些早期研究要么在研究患者数量上有限，要么仅研究单一药物。由于检测条件未标准化，这些研究也存在不足。本研究比较了三种低分子量肝素（速碧林、克赛、弗希肝素）和一种类肝素（奥加诺）与HIT抗体的交叉反应率。在标准化条件下，使用血小板聚集测定法检测了45例HIT患者的血清。交叉反应率分别为：7%（奥加诺）、89%（速碧林）、83%（克赛）和86%（弗希肝素）。虽然尚无对照试验来确定低分子量肝素和类肝素的体内交叉反应率，但后者较低的体外交叉反应率有利于其在HIT中的应用。然而，在这些药物用于HIT治疗之前，应排除体外交叉反应。
