Urbanus R T, de Laat H B, de Groot P G, Derksen R H W M
Department of Rheumatology and Clinical Immunology, University Medical Center, 3508 GA Utrecht, The Netherlands.
Arthritis Rheum. 2004 Nov;50(11):3605-9. doi: 10.1002/art.20586.
Systemic lupus erythematosus and antiphospholipid syndrome (APS) often appear concomitantly. Lupus nephritis and antiphospholipid antibody-related ischemic nephropathy cannot be distinguished clinically, although their etiology and treatment differ greatly. Examination of a renal biopsy sample is therefore essential in order to provide the correct treatment. We have observed that patients with lupus anticoagulant (LAC), a serologic marker for APS, often have a prolonged bleeding time, which is a contraindication for performing a percutaneous renal biopsy. We undertook this study to evaluate systematically the bleeding time in 27 consecutive patients.
The bleeding time was measured in 27 patients who were persistently positive for LAC and who were not exposed to aspirin or nonsteroidal antiinflammatory drugs. Platelet function and von Willebrand factor (vWF) parameters were subsequently assessed in patients with a prolonged bleeding time.
Twenty-one of 27 patients (78%) had a prolonged bleeding time despite a normal platelet count in the majority of patients (81%). Platelet functioning and vWF parameters in these 21 patients were normal, except for those in 1 patient with a mild storage pool disease.
With this study, we introduce yet another paradox in the phenomenon of APS. Although a prolonged bleeding time is generally accepted to be a sign of defective primary hemostasis, LAC is associated with thrombosis. Further studies are needed to elucidate the mechanism behind this disturbance of primary hemostasis.
系统性红斑狼疮和抗磷脂综合征(APS)常同时出现。狼疮性肾炎和抗磷脂抗体相关的缺血性肾病在临床上难以区分,尽管它们的病因和治疗方法差异很大。因此,检查肾活检样本对于提供正确的治疗至关重要。我们观察到,作为APS血清学标志物的狼疮抗凝物(LAC)阳性患者通常出血时间延长,这是经皮肾活检的禁忌证。我们进行这项研究以系统评估27例连续患者的出血时间。
对27例LAC持续阳性且未服用阿司匹林或非甾体类抗炎药的患者测量出血时间。随后对出血时间延长的患者评估血小板功能和血管性血友病因子(vWF)参数。
27例患者中有21例(78%)出血时间延长,大多数患者(81%)血小板计数正常。这21例患者中,除1例患有轻度储存池病的患者外,血小板功能和vWF参数均正常。
通过这项研究,我们在APS现象中又发现了一个矛盾之处。虽然出血时间延长通常被认为是原发性止血缺陷的标志,但LAC与血栓形成有关。需要进一步研究以阐明这种原发性止血障碍背后的机制。