先天性因子Ⅻ缺乏症,国内仅见4例报道,我们遇见1例,报道如下。庄某,男,21岁,患者出生时脐带曾出血不止,3岁后,口腔粘膜常出血难止。近年每因劳累后即出现血尿,无尿痛、尿频、尿急现象。父母健康,无出血史。其妹出生时亦脐出血不止。5岁时头 Congenital factor Ⅻ deficiency, only 4 cases reported in China, we met 1 case, reported as follows. Zhuangmou, male, 21 years old, had bleeding from the umbilical cord when she was born. After 3 years of age, oral mucosa often bleeds. In recent years, hematuria occurs after each exertion, no dysuria, frequent urination, urinary urgency. Parents health, no history of bleeding. His sister also born when umbilical bleeding more than. 5 years old head