title: [A follow-up study of the development of factor VIII inhibitor in Chinese patients with hemophilia A].
abstract: OBJECTIVE
  To study the incidence and characteristics of coagulation factor VIII (FVIII) inhibitor development in Chinese patients with hemophilia A.
  
  
  METHODS
  A 24-month continuous follow-up was conducted among 215 Chinese patients with hemophilia A to observe the characteristics of FVIII inhibitor development and the clinical characteristics of the patients.
  
  
  RESULTS
  The cumulative incidence of FVIII inhibitor development in 24 months was 11.6% (25/215) in these patients. Of the 25 patients with FVIII inhibitor development, 18 (72%) had low-titer inhibitors and 7 (28%) had high-titer inhibitors. The patients developed the inhibitors after a median of 150 exposure days at a median age of 25 years (6-59 years). Fifteen patients with low-titer inhibitors (median 1.25 BU/ml) showed gradual disappearance of the inhibitors in a median of 10 months (6-15 months) without any treatment, and 5 patients with high-titer inhibitors (median 100 BU/ml) remained positive in 24 months; the other 5 FVIII inhibitor-positive cases showed no significant changes. In the 25 patients developing FVIII inhibitors, the bleeding frequency increased significantly (P=0.025), and in 18 of the patients who continued to use FVIII products, a significant increase in the dose of medication was noted (P=0.015), but the number of target joints did not increase in 24 months (P=0.329).
  
  
  CONCLUSIONS
  The incidence and characteristics of factor VIII inhibitor development differ between Chinese patients with hemophilia A and those in developed countries.
authors.affiliation: Department of Hematology, Nanfang Hospital, Southern Medical University, Guangzhou, China. zhouxuan@fimmu.com
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhou
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D005169:Factor VIII / Q000037:antagonists & inhibitors*; D005500:Follow-Up Studies; D006467:Hemophilia A / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D005169:Factor VIII