Inherited factor VII (FVII) deficiency is the most common among the autosomal recessive rare bleeding disorders, with an estimated prevalence of 1:300,000 in European countries. Affected individuals display a wide range of clinical phenotypes, ranging from mild non spontaneous bleeding to life threatening (i.e. central nervous system[CNS] bleeding, gastrointestinal [GI] bleeding or haemarthrosis), whereas up to one-third of individuals with a FVII deficiency are asymptomatic and are mainly diagnosed during family studies or after screening for surgery. Unfortunately, the residual activity of FVII does not predict the individual propensity to bleed, and even in individuals with the same mutation, differences in clotting phenotypes can be seen.
As our tertiary center serves a unique population in the Negev, we aimed at studying the prevalence and phenotype of FVII deficiency within the last decade.
Methods: We searched all electronic records for the last 10 years depicting rare bleeding disorders by ICD 9 code - 2863 and compared them to the hematologic record of factor VII deficiency depicted in our lab - 50% or less activity. Patients with any record of genetic diagnosis, were compared with clinical findings.
Results: The population in the Negev is estimated as 700000 people
Most of them are Jewish and 150000 of them are Arab-Bedouins. We found 800 records of rare bleeding disorders (ICD 9-2863), Including 200 with FVII deficiency - 100/200 had FVII levels below 50%.
Most (90%) of cases were of Jewish origin (mostly oriental Jews) and only 10% were Arab- Bedouins. Forty patients were asymptomatic with 50-30% FVII activity and 20 patients with 30-10% FVII activity were either asymptomatic or presented with mild bleeding diathesis. Out of 23 cases with lower than 10% FVII activity, 7 were symptomatic and suffered severe life threatening bleedings (2 infant died of perinatal ICH. Five families (3 Bedouin and 2 oriental Jews) were identified with severe FVII deficiencies. The 4 Bedouin patients were identified to be homozygous to unique mutation. Interestingly, most medical records depicted FVII deficiency were of women studies due to fertility problems.
Conclusions: The prevalence of FVII deficiency depicted in the Negev is much higher in comparison to literature reports (200/700000) Severe FVII deficiency was found in 23: 700000, consistent with 1: 30000 prevalence. As patients are highly variable, in order to "tailor" treatments according to disease severity, new directions should be pursued to identify those with the most severe phenotypes.
Kenet:Bayer, Novo Nordisk: Other: Advisory Boards, Speakers Bureau; Opko Biologics: Consultancy, Other: Advisory Boards; BPL; Baxelta: Research Funding; Pfizer: Honoraria.
Asterisk with author names denotes non-ASH members.