目的：探讨1-去氨基-8-D-精氨酸加压素（DDAVP，商品名：弥凝)治疗对轻型血友病A患儿血浆凝血因子Ⅷ（FⅧ）、活化部分凝血活酶时间（APTT）的影响。方法：轻型血友病A患儿18例，用DDAVP静脉注射治疗（每日0.3 μg/kg），每24 h一次，连续用5次。观察患儿临床疗效，并于DDAVP注射前及注射后测定血浆FⅧ水平及APTT。结果：DDAVP治疗后，18例患儿中16例出血症状明显减轻，关节肌肉血肿肿痛减轻或消失。首日用药后60 min 血浆FⅧ 达（27±4）%，APTT时间缩短至（66±10）s；DDAVP治疗的第3~4日FⅧ水平维持在有效止血水平（25%~30%）；与前4日比较，第5日FⅧ浓度明显下降［(21±3)%］，APTT也随之延长。结论：DDAVP可显著提高轻型血友病A患儿血浆FⅧ水平，明显缩短其APTT，临床出血症状得到较好控制，建议DDAVP疗程以3~4日为宜。

OBJECTIVE: To study the effects of desmopressin (DDAVP) on coagulation factor Ⅷ (FⅧ) and activated partial thromboplastin time (APTT) in children with mild hemophilia A. METHODS: Eighteen children with mild hemophilia A were enrolled. DDAVP (0.3 μg/kg?d) was injected intravenously for 5 days. Plasma FⅧ levels and APTT were measured before and after DDAVP treatment. RESULTS: In 16 of 18 children with mild hemophilia A, the bleeding symptoms, including the articular or musclar hematoma, were significantly alleviated as a result of DDAVP treatment. The plasma FⅧ levels increased significantly to (27±4)% and APTT was shortened to (66±10)s 60 minutes after the first dose of DDAVP treatment. The plasma FⅧ remained at the levels of 25%-30% during 3-4 days of DDAVP treatment. Five days after DDAVP treatment, the plasma FⅧ levels decreased ［(21±3)%］, and APTT was prolonged when compared with 1-4 days of DDAVP treatment. CONCLUSIONS: DDAVP treatment can increase plasma FⅧ levels and shorten APTT in children with mild hemophilia A. DDAVP is effective in the treatment of mild hemophilia A. The duration of DDAVP therapy for mild hemophilia A is recommended as 3 to 4 days.