十二、紫癜紫癜是皮肤、粘膜小血管血液渗入皮肤、粘膜组织间隙的表现,是出血性疾病的常见症状之一,通常由血管壁病变、血小板异常及凝血障碍引起。出血范围的大小和广泛程度视病因和病情而异。小于2毫米者称瘀点(出血点),大于2毫米者称瘀斑(紫癜),可高出或不高出皮肤、粘膜表面,压之不褪色。新鲜的紫癜呈鲜红色,继之变暗红色,最终变棕黄色而吸收消散。根据止血和凝血机理异常,可将出血性疾病归类 Purpura purpura is the skin, mucosal blood vessels into the skin, mucosal tissue gap performance, is one of the common symptoms of hemorrhagic disease, usually caused by vascular wall lesions, abnormal platelets and coagulation disorders. The extent and extent of bleeding depends on the cause and condition. People less than 2 millimeters said petechiae (bleeding point), more than 2 millimeters said ecchymosis (purpura), may be higher or lower than the skin, mucosal surface, the pressure of fade. Fresh purpura bright red, followed by dark red, the final change brown and absorb dissipated. According to hemostasis and coagulation abnormalities, hemorrhagic disease can be classified