Hemophilia

Surveillance data suggest hemophilia incidence of 1 in 4334 live male births in the US.[4]Soucie JM, Miller CH, Dupervil B, et al. Occurrence rates of haemophilia among males in the United States based on surveillance conducted in specialized haemophilia treatment centres. Haemophilia. 2020 May;26(3):487-93. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8117262 http://www.ncbi.nlm.nih.gov/pubmed/32329553?tool=bestpractice.com The exact number of people living with hemophilia in the US is not known; however, based on data collected during the period 2012-2018, it is thought that as many as 33,000 males in the US are living with the disorder.[4]Soucie JM, Miller CH, Dupervil B, et al. Occurrence rates of haemophilia among males in the United States based on surveillance conducted in specialized haemophilia treatment centres. Haemophilia. 2020 May;26(3):487-93. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8117262 http://www.ncbi.nlm.nih.gov/pubmed/32329553?tool=bestpractice.com [5]Centers for Disease Control and Prevention. Data & statistics on hemophilia. Sep 2020 [internet publication]. https://www.cdc.gov/ncbddd/hemophilia/data.html

Congenital hemophilia affects all ethnic groups and has a worldwide distribution.[6]World Federation of Hemophilia. Report on the annual global survey, 2017. Oct 2018 [internet publication]. http://www1.wfh.org/publications/files/pdf-1714.pdf Its inheritance pattern is X-linked.[7]Pruthi RK. Hemophilia: a practical approach to genetic testing. Mayo Clin Proc. 2005 Nov;80(11):1485-99. http://www.ncbi.nlm.nih.gov/pubmed/16295028?tool=bestpractice.com Therefore, boys and/or men are almost exclusively affected, although many female carriers (approximately 30%) have clotting factor levels in the hemophilia range due to lyonization (random inactivation of the normal X chromosome) and may have bleeding symptoms requiring appropriate management. Rare cases of girls and/or women with severe hemophilia are described because of extreme lyonization, homozygosity, mosaicism, or Turner syndrome.

Acquired hemophilia affects around 1 to 3 people per million of the population. Both sexes are equally affected. As with the conventional inherited form, the condition appears in all ethnic groups and has a worldwide prevalence.