Berdeaux D H, Abshire T C, Marlar R A
Department of Internal Medicine/SGHM, Keesler Technical Training Center Medical Center, Keesler AFB, MS 39534-5300.
Am J Clin Pathol. 1993 Jun;99(6):677-86. doi: 10.1093/ajcp/99.6.677.
A cause of recurrent venous thrombosis is discernible in about 30% of symptomatic patients. Type I protein C (PC) deficiency (concomitant decrease of activity and antigen) is a well-described cause of venous thrombosis. Dysfunctional PC or type II PC deficiency (a disproportionate decrease in activity compared with antigen), however, is less well understood. Eleven subjects from three American families had dysfunctional PC. The patient base was moderately sized. These 11 subjects are compared with the 67 patients (39 symptomatic and 28 asymptomatic) that have been reported with dysfunctional PC at this time. Dysfunctional protein C deficiency is a more common cause of venous thrombosis than previously was recognized. Protein C activity should be determined in evaluating a patient with recurrent venous thromboses or thrombosis in early adult life. If the PC activity is low, repeat PC activity and a PC antigen levels should be determined so that patients with Type II PC deficiency will be identified. Further testing must include family studies to rule out an acquired deficiency and confirm the hereditary basis of the Type II PC deficiency.
在约30%有症状的患者中可发现复发性静脉血栓形成的原因。I型蛋白C（PC）缺乏症（活性和抗原同时降低）是一种已被充分描述的静脉血栓形成原因。然而，功能失调的PC或II型PC缺乏症（与抗原相比活性不成比例地降低）则了解较少。来自三个美国家庭的11名受试者存在功能失调的PC。患者群体规模适中。将这11名受试者与目前已报道的67例功能失调PC患者（39例有症状，28例无症状）进行比较。功能失调的蛋白C缺乏症是静脉血栓形成比以前认识到的更常见的原因。在评估患有复发性静脉血栓或成年早期血栓形成的患者时，应测定蛋白C活性。如果PC活性低，应重复测定PC活性并测定PC抗原水平，以便识别出II型PC缺乏症患者。进一步的检测必须包括家族研究，以排除获得性缺乏症并确认II型PC缺乏症的遗传基础。
