资料 男,8个月,以双下肢疼痛20天,齿龈出血1周为主诉入院。既往健康,20天前常出现无诱因的哭叫,双下肢不收伸直,运动减少。近1周上齿龈出血。足月、顺产第1胎,生后一直人工牛乳喂养,未添加过任何辅食,不吃水果。母孕史、家族史无特殊记载。查体:T36.7℃,P104次/分,R35次/分。神志清楚,发育中等周身皮肤无出血点,上齿龈肿胀明显,心肺听诊正常, Data male, 8 months to 20 days of pain in both lower extremities, gum bleeding for 1 week based on admission. Past health, 20 days ago, there is often no incentive to cry, both lower extremities do not receive straight, exercise reduced. Nearly 1 week on the gum bleeding. Full-term, first-trimester birth, has been artificial milk after birth, did not add any food supplement, do not eat fruit. Mother’s pregnancy history, family history no special records. Physical examination: T36.7 ℃, P104 times / min, R35 times / min. Consciousness, the development of moderate whole body skin without bleeding, obvious swelling on the gums, cardiopulmonary auscultation normal,