PB0571 - Congenital factor Ⅴ deficiency in China

Monday, June 24, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

Yu Yang, M.Med

Student
State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin Key Laboratory of Gene Therapy for Blood Diseases, CAMS Key Laboratory of Gene Therapy for Blood Diseases, Tianjin 300020, China
Tianjin, Tianjin, China (People's Republic)

Co-Author(s)

LC

Lingling Chen

professor
State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin Key Laboratory of Gene Therapy for Blood Diseases, CAMS Key Laboratory of Gene Therapy for Blood Diseases, Tianjin 300020, China
Tianjin, Tianjin, China (People's Republic)
LZ

Lei Zhang

professor
State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin Key Laboratory of Gene Therapy for Blood Diseases, CAMS Key Laboratory of Gene Therapy for Blood Diseases, Tianjin 300020, China
Tianjin, Tianjin, China (People's Republic)
Renchi Yang, MD

Head of Thrombosis and Hemostasis Center
Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College
Tianjin, Hebei, China (People's Republic)

Background: Congenital factor Ⅴ (FⅤ) deficiency, a rare bleeding disorder, is linked to recessive mutations in the F5 gene. The National Hemophilia Registration System of China was established to track patients with hemophilia and other rare bleeding disorders.

Aims: To investigate the current status and F5 genotype of patients with congenital FⅤ deficiency throughout China.

Methods: We collected clinical phenotype information and genotype data from patients registered in the system, using electronic medical records and telephone follow-up. Informed consent was obtained from all patients before follow-up. Statistical analysis was conducted using SPSS 26.0 and GraphPad Prism 8.

Results: Overall 31 congenital FV deficiency patients were followed up, comprising 12 males and 19 females, aged between 5.7 and 73.7 years. Among the 25 patients with available medical history, 16% were asymptomatic. Hemorrhagic events were classified as Grade I, II, and III, occurring in 28%, 48%, and 8% of patients, respectively. The most common symptoms were cutaneous (35.5%) and gingival bleeding (32.3%), with 26.3% of females experiencing menorrhagia. FV activity ranged from 0.001 to 17.4, with 3.2% mild (FV: C > 10%), 80.6% moderate (FV: C 1% to 10%), and 16.1% severe (FV: C < 1%) cases. The correlation between FⅤ: C and bleeding symptoms is shown in Figure 1. Genetic analysis identified 19 variants in 13 patients, predominantly missense (52.6%) and heterozygous (82.6%) variants. Notably, 10 pathogenic or likely pathogenic mutations were reported for the first time (Table 1). Ten patients (40%), including 4 asymptomatic, 2 Grade Ⅰ, and 4 Grade Ⅱ bleeders, had not received replacement therapy. Most patients were treated with fresh frozen plasma (60%) or cryoprecipitate (16%) as on-demand replacement therapy.

Conclusion(s): This study provides a comprehensive view of FⅤ deficiency patients in China, enriching the F5 gene mutation spectrum of the Asian population.