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==Overview==
==Overview==
'''Hemophilia A''' is a [[blood]] [[coagulation|clotting]] disorder caused by a mutation of the [[factor VIII]] gene, leading to a deficiency in Factor VIII. It is the most common [[hemophilia]]. Inheritance is [[X-linked]] recessive; hence, males are affected while females are carriers or very rarely display a mild [[phenotype]]. 1 in 5,000 males are affected.
[['''Hemophilia A''']] is a [[blood]] [[coagulation|clotting]] disorder caused by a mutation of the [[factor VIII]] gene, leading to a deficiency in Factor VIII. It is the most common [[hemophilia]]. Inheritance is [[X-linked]] recessive; hence, males are affected while females are [[carriers]] or very rarely display a mild [[phenotype]]. 1 in 5,000 males are affected.
 
"[[Hemophilia B]]" is also a blood clotting disorder similar to Hemophilia A to the extent that these two diseases have been considered clinically indistinguishable. Hemophilia B inheritance is also  X-linked, however it is caused by the mutation of [[factor IX]] gene. The overall clinical severity of Hemophilia B in terms of equal amount of factor deficency is believed to be less severe than Hemophilia A, besides the prevalence of the disease is also lower; 1 in 30,000 males<ref name="pmid23818083">{{cite journal| author=Zimmerman B, Valentino LA| title=Hemophilia: in review. | journal=Pediatr Rev | year= 2013 | volume= 34 | issue= 7 | pages= 289-94; quiz 295 | pmid=23818083 | doi=10.1542/pir.34-7-289 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23818083  }}</ref>.
 
There is also another type of bleeding disorder related to deficiency of [[factor XI]] known as Hemophilia C, it is a rare [[autosomal]] disease with usually mild phenotype and is almost exclusively seen in Ashkenazi Jews<ref name="pmid23929304">{{cite journal| author=Duga S, Salomon O| title=Congenital factor XI deficiency: an update. | journal=Semin Thromb Hemost | year= 2013 | volume= 39 | issue= 6 | pages= 621-31 | pmid=23929304 | doi=10.1055/s-0033-1353420 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23929304  }}</ref> hence the concentration of our Hemophilia page here is mostly directed towards Hemophilia A and B.  


==Historical Perspective==
==Historical Perspective==
Hemophilia is sometimes referred to as “The Royal Disease”, as it affected many members of the English, German, Russian and Spanish monarchies in the 19th and 20th centuries.
Hemophilia is sometimes referred to as “The Royal Disease”, as it affected many members of the English, German, Russian and Spanish monarchies in the 19th and 20th centuries.<ref name="pmid22551339">{{cite journal| author=Franchini M, Mannucci PM| title=Past, present and future of hemophilia: a narrative review. | journal=Orphanet J Rare Dis | year= 2012 | volume= 7 | issue=  | pages= 24 | pmid=22551339 | doi=10.1186/1750-1172-7-24 | pmc=3502605 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=22551339  }} </ref>
 
In 1947, It was found that blood donations from a Hemophilia patient can cure clotting disorder in another Hemophilia patient. This was the start point to distinguish two major forms of Hemophilia which were later named A and B.


==Classification==
==Classification==
Hemophilia A may be classified according to the amount of Factor VIII present, resulting in either a mild, moderate, or severe form of the disease. <ref>How is Hemophilia Diagnosed? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/diagnosis. Accessed on July 30, 2016 </ref>
Hemophilia A and B and C are classified according to the amount of Factor VIII/ IX/ XI present respectively, resulting in either a mild, moderate, or severe form of the disease.<ref>How is Hemophilia Diagnosed? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/diagnosis. Accessed on July 30, 2016 </ref>


==Pathophysiology==
==Pathophysiology==
The pathogenesis of hemophilia A is characterized by genetic deficiency in Factor VIII.
Mainly, the pathogenesis of hemophilia A is characterized by genetic deficiency in Factor VIII. And similarly the pathogenesis of hemophilia B is characterized by genetic deficiency in Factor IX. Albeit, not all cases of Hemophilia are genetic disorders and there are several case reports of acquired forms of these diseases.  


==Causes==
==Causes==
[[Hemophilia A]] is caused by an inherited [[X-linked]] [[recessive trait]], with the defective [[gene]] located on the [[X chromosome]].
Hemophilia A and B are caused by an inherited X-linked [[recessive trait]], with defective [[gene]]<nowiki/>s located on the [[X chromosome]].


==Differentiating [Disease] from Other Diseases==
==Differentiating Hemophilia from Other Diseases==
Hemophilia A must be differentiated from other diseases that cause abnormal or excessive bleeding <ref> Konkle BA, Josephson NC, Nakaya Fletcher S. Hemophilia A. 2000 Sep 21 [Updated 2014 Jun 5]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016. Available from: http://www-ncbi-nlm-nih-gov.laneproxy.stanford.edu/books/NBK1404/ </ref>
Hemophilia must be differentiated from other diseases that cause abnormal or excessive [[bleeding]].<ref>Konkle BA, Josephson NC, Nakaya Fletcher S. Hemophilia A. 2000 Sep 21 [Updated 2014 Jun 5]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016. Available from: http://www-ncbi-nlm-nih-gov.laneproxy.stanford.edu/books/NBK1404/ </ref>


The most important [[differential diagnosis]] is that of [[hemophilia B]] (also known as Christmas disease) or [[von Willebrand disease]]. The former is usually considered if factor VIII levels are normal in a person with a haemophilia phenotype. The latter is excluded on routine testing for that condition.
The most important [[differential diagnosis]] of Hemophilia A is that of [[hemophilia B]] or [[von Willebrand disease]]. The former is usually considered if factor VIII levels are normal in a person with a hemophilia [[phenotype]]. The latter is excluded on routine testing for that condition.


==Epidemiology and Demographics==
==Epidemiology and Demographics==
The incidence of Hemophilia A is approximately 1 per 5,000 to 10,000 males worldwide. In 2016, it was estimated that 20,000 males in the United States were living with Hemophilia A <ref> What is Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia. Accessed on Sept 20, 2016 </ref>
The [[incidence]] of Hemophilia A is approximately 1 per 5,000 to 10,000 males worldwide. In 2016, it was estimated that 20,000 males in the United States were living with Hemophilia A.The incidence of Hemophilia B is estimated 1 per 30,000 males.<ref>What is Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia. Accessed on Sept 20, 2016 </ref><ref name="pmid23818083" /> The incidence of Hemophilia C is populations is estimated to be about 1:1,000,000 worldwide while it is much higher among Ashkenazi Jews (1:450)<ref name="pmid23929304" />.


==Risk Factors==
==Risk Factors==
Risk factors for development of hemophilia A include being of male sex and having a positive family history of the disease.
Risk factors for development of Hemophilia include being of male sex and having a positive [[family history]] of the disease.


==Screening==
==Screening==
Screening for hemophilia A revolves around obtaining a thorough family history of bleeding.
Screening for Hemophilia revolves around obtaining a thorough family history of bleeding.


==Natural History, Complications, and Prognosis==
==Natural History, Complications, and Prognosis==
*Hemophilia A presentation varies depending on the stage of the disease: <ref>Severity of Hemophilia – World Federation of Hemophilia. Available at http://www.wfh.org/en/page.aspx?pid=643. Accessed on July 30,2016 </ref>
*Hemophilia presentation varies depending on the stage of the disease:<ref>Severity of Hemophilia – World Federation of Hemophilia. Available at http://www.wfh.org/en/page.aspx?pid=643. Accessed on July 30,2016 </ref>
**People with mild hemophilia (5-40% of factor VIII activity in the blood) generally present with excessive bleeding following surgery (such as a dental procedure) or trauma. They may remain asymptomatic otherwise for long period of time, even into late adulthood
**People with mild hemophilia (5-40% of factor VIII/ IX activity in the blood) generally present with excessive bleeding following [[surgery]] (such as a dental procedure) or [[trauma]]. They may remain asymptomatic otherwise for long period of time, even into late adulthood
**People with moderate hemophilia (1-5% of factor VIII activity in the blood) have presentation ranging between mild and severe forms. They present earlier than patients with mild hemophilia, and may bleed following minor trauma
**People with moderate hemophilia (1-5% of factor VIII/ IX activity in the blood) have presentation ranging between mild and severe forms. They present earlier than patients with mild hemophilia, and may bleed following minor trauma
**People with severe hemophilia (less than 1% of factor VIII in blood) present sooner in life with abnormal bleeding episodes, usually in the first year of life. They are also at risk for spontaneous hemorrhages, i.e. unprovoked bleeding episodes, frequently in the joints and muscles
**People with severe hemophilia (less than 1% of factor VIII/ IX in blood) present sooner in life with abnormal bleeding episodes, usually in the first year of life. They are also at risk for spontaneous hemorrhages, i.e. unprovoked bleeding episodes, frequently in the [[joints]] and [[muscles]]


===Natural History===
===Natural History===
Clinical features are usually related to abnormal or spontaneous bleeding, and can be separated into internal bleeds and external bleeds <ref> What are the signs and symptoms of Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/signs. Accessed on Sept 20, 2016 </ref> <ref> Types of Bleeds | National Hemophilia Foundation. Available at https://www.hemophilia.org/Bleeding-Disorders/Types-of-Bleeds . Accessed on Sept 20, 2016 </ref>
Clinical features are usually related to abnormal or spontaneous bleeding, and can be separated into internal bleeds and external bleeds.<ref>What are the signs and symptoms of Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/signs. Accessed on Sept 20, 2016 </ref> <ref>Types of Bleeds | National Hemophilia Foundation. Available at https://www.hemophilia.org/Bleeding-Disorders/Types-of-Bleeds . Accessed on Sept 20, 2016 </ref>


===Complications===
===Complications===
Many of the long-term sequelae of hemophilia A are either related to the morbidity of severe bleeds, or from side effects of frequent transfusions
Many of the long-term sequelae of Hemophilia  are either related to the morbidity of severe bleeds, or from side effects of frequent [[transfusions]].


===Prognosis===
===Prognosis===
With appropriate assistance and education, patients with Hemophilia can live productive lives, both in terms of longevity and quality of life. The prognosis of these patients is helped greatly with the availability of replacement therapy.
With appropriate assistance and education, patients with Hemophilia can live productive lives, both in terms of longevity and quality of life. The [[prognosis]] of these patients is helped greatly with the availability of more effective replacement therapy.


==Diagnosis==
==Diagnosis==
===Diagnostic Criteria===
===Diagnostic Criteria===
The diagnosis may be suspected as coagulation testing reveals an increased [[partial thromboplastin time|PTT]] in the context of a normal [[prothrombin time|PT]] and [[bleeding time]]. The diagnosis is made in the presence of very low (<10 IU) levels of factor VIII.
The initial phase of diagnosis is based on clinical findings of bleeding and a positive family history in majority of cases. The diagnosis may be suspected as [[coagulation]] testing reveals an increased [[partial thromboplastin time]] ([[PTT]]) in the context of a normal [[prothrombin time]] ([[PT]]) and [[bleeding time]].<ref name="pmid25356200">{{cite journal| author=Cortegiani A, Russotto V, Foresta G, Montalto F, Strano MT, Raineri SM et al.| title=A perioperative uncontrollable bleeding in an elderly patient with acquired hemophilia A: a case report. | journal=Clin Case Rep | year= 2013 | volume= 1 | issue= 1 | pages= 3-6 | pmid=25356200 | doi=10.1002/ccr3.2 | pmc=4184532 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=25356200  }} </ref> The diagnosis is made in the presence of very low (<10 IU) levels of factor VIII/ IX.


===History and Symptoms===
===History and Symptoms===
Hemophilia leads to a severely increased risk of bleeding from common injuries. Mild hemophilia is usually asymptomatic, unless the patient experiences an injury or undergoes surgery. Bleeding into large joints or muscles is the most common site of bleeding in hemophilia. Though uncommon, spontaneous or traumatic intracranial hemorrhages are the most catastrophic complication of hemophilia.
Hemophilia leads to a severely increased risk of bleeding from common injuries. Mild hemophilia is usually asymptomatic, unless the patient experiences an injury or undergoes surgery. Bleeding into large joints or muscles is the most common site of bleeding in hemophilia. Though uncommon, spontaneous or traumatic [[intracranial hemorrhages]] are the most catastrophic complication of hemophilia.


===Physical Examination===
Physical exam findings in Hemophilia are usually related to the site of bleeding.<ref>What are the signs and symptoms of Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/signs. Accessed on Sept 20, 2016 </ref>
Physical exam findings are in Hemophilia A are usually related to the site of bleeding. <ref> What are the signs and symptoms of Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/signs. Accessed on Sept 20, 2016 </ref>


===Laboratory Findings===
===Laboratory Findings===
The typical coagulation profile of a patient with hemophilia A usually presents as the following: <ref> Diagnosis | Hemophilia | NCBDDD | CDC. Available at http://www.cdc.gov/ncbddd/hemophilia/diagnosis.html. Accessed on Sept 20, 2016 </ref>
The typical coagulation profile of a patient with hemophilia A usually presents as the following:<ref>Diagnosis | Hemophilia | NCBDDD | CDC. Available at http://www.cdc.gov/ncbddd/hemophilia/diagnosis.html. Accessed on Sept 20, 2016 </ref>
:*Prolonged [[partial thromboplastin time]] ([[PTT]])
:*Prolonged partial thromboplastin time (PTT)
:*Normal prothrombin time
:*Normal prothrombin time
:*Normal [[bleeding time]]
:*Normal [[bleeding time]]
:*Normal [[fibrinogen]] level
:*Normal [[fibrinogen]] level
:*Low [[factor VIII]]
:*Low [[factor VIII|factor VIII/]] [[Factor IX|IX]]/ XI


Other laboratory findings consistent with the diagnosis of hemophilia A include correction of the PTT with a 1:1 mixing study (i.e. factor VIII from the normal blood mixed with the hemophiliac blood is able to correct for the coagulation deficit)
Other laboratory findings consistent with the diagnosis of hemophilia A include correction of the PTT with a 1:1 mixing study (i.e. factor VII/ IX from the normal blood mixed with the hemophiliac blood is able to correct for the coagulation deficit).


===Imaging Findings===
===Imaging Findings===
There are no imaging findings classically associated with hemophilia
There are no imaging findings classically associated with Hemophilia.


===Other Diagnostic Studies===
===Other Diagnostic Studies===
Genetic testing appears to be a promising means of determining an individual's risk of attaining or passing on Hemophilia.
[[Genetic testing]] appears to be a promising means of determining an individual's risk of attaining or passing on Hemophilia.


==Treatment==
==Treatment==
There is no definitive treatment for hemophilia A, the mainstay of therapy is supportive and preventative care. It is recommended that patients diagnosed with hemophilia be referred to hemophilia treatment centers (HTC), which provide coordinated care between physicians (usually hematologists), nurses, social workers and other staff who specialize in bleeding disorders. <ref> Konkle BA, Josephson NC, Nakaya Fletcher S. Hemophilia A. 2000 Sep 21 [Updated 2014 Jun 5]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016. Available from: http://www-ncbi-nlm-nih-gov.laneproxy.stanford.edu/books/NBK1404/ </ref>
There is no definitive treatment for hemophilia , the mainstay of therapy is supportive and preventative care. It is recommended that patients diagnosed with hemophilia be referred to hemophilia treatment centers (HTC), which provide coordinated care between physicians (usually hematologists), nurses, social workers and other staff who specialize in bleeding disorders.<ref>Konkle BA, Josephson NC, Nakaya Fletcher S. Hemophilia A. 2000 Sep 21 [Updated 2014 Jun 5]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016. Available from: http://www-ncbi-nlm-nih-gov.laneproxy.stanford.edu/books/NBK1404/ </ref>


===Medical Therapy===
===Medical Therapy===
Most haemophilia patients require regular supplementation with [[intravenous]] [[recombinant]] factor VIII, also known as replacement therapy. Apart from "routine" supplementation, extra factor concentrate is given around surgical procedures and after trauma, as well as emergently during any bleeding episode. <ref> Treatment of Hemophilia – World Federation of Hemophilia. Available at http://www.wfh.org/en/page.aspx?pid=642. Accessed on Sept 20, 2016 </ref>
Most Hemophilia patients require regular supplementation with [[intravenous]] [[recombinant]] factor VIII/ IX, also known as replacement therapy. Apart from "routine" supplementation, extra factor concentrate is given around surgical procedures and after trauma, as well as emergently during any bleeding episode.<ref>Treatment of Hemophilia – World Federation of Hemophilia. Available at http://www.wfh.org/en/page.aspx?pid=642. Accessed on Sept 20, 2016 </ref>


Other therapeutic options include cryoprecipitate, fresh frozen plazma (FFP), desmopressin (DDAVP), and anti-fibrinoltytic agents.
Other therapeutic options include [[cryoprecipitate]], [[fresh frozen plazma]] ([[FFP]]), [[desmopressin]] ([[DDAVP]]), and anti-fibrinoltytic agents.


===Surgery===
===Surgery===
There is no role for surgery in the routine treatment of Hemophilia. Surgical intervention however may be requ
[[Category:Hematology]]
[[Category:Pediatrics]]
ired in cases where hematomas or bleeds from the disease process cannot be managed conservatively, i.e. with major intracranial hemorrhages


===Prevention===
===Prevention===
There are no established measures for the [[primary prevention]] of Hemophilia.
[[Secondary prevention]] for hemophilia is aimed at preventing spontaneous or excessive bleeds in patients who are high risk, and relies on the use of recombinant clotting factor VIII/ IX administration on a regular basis to prevent bleeding episodes.


==References==
==References==
{{reflist|2}}
{{reflist|2}}
#History of Bleeding Disorders | National Hemophilia Foundation. Available at . Accessed on July 30, 2016
#How is Hemophilia Diagnosed? – NHLBI, NIH. Available at . Accessed on July 30, 2016
#Severity of Hemophilia – World Federation of Hemophilia. Available at . Accessed on July 30,2016
#Facts | Hemophilia | NCBDDD | CDC. Available at . Accessed on July 30,2016
#Data & Statistics | Hemophilia | NCBDDD | CDC. Available at  Accessed on July 30,2016
#Handbook of Genetic Counseling/Hemophilia and Von Willebrand Disease – Wikibooks, open books for an open world. Available at  Accessed on July 30,2016
#Konkle BA, Josephson NC, Nakaya Fletcher S. Hemophilia A. 2000 Sep 21 [Updated 2014 Jun 5]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016. Available from:http://www-ncbi-nlm-nih-gov.laneproxy.stanford.edu/books/NBK1404/


{{WH}}
{{WH}}
{{WS}}
{{WS}}
[[Category:Hematology]]
[[Category:Pediatrics]]

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Fahd Yunus, M.D. [2]

Overview

'''Hemophilia A''' is a blood clotting disorder caused by a mutation of the factor VIII gene, leading to a deficiency in Factor VIII. It is the most common hemophilia. Inheritance is X-linked recessive; hence, males are affected while females are carriers or very rarely display a mild phenotype. 1 in 5,000 males are affected.

"Hemophilia B" is also a blood clotting disorder similar to Hemophilia A to the extent that these two diseases have been considered clinically indistinguishable. Hemophilia B inheritance is also X-linked, however it is caused by the mutation of factor IX gene. The overall clinical severity of Hemophilia B in terms of equal amount of factor deficency is believed to be less severe than Hemophilia A, besides the prevalence of the disease is also lower; 1 in 30,000 males[1].

There is also another type of bleeding disorder related to deficiency of factor XI known as Hemophilia C, it is a rare autosomal disease with usually mild phenotype and is almost exclusively seen in Ashkenazi Jews[2] hence the concentration of our Hemophilia page here is mostly directed towards Hemophilia A and B.

Historical Perspective

Hemophilia is sometimes referred to as “The Royal Disease”, as it affected many members of the English, German, Russian and Spanish monarchies in the 19th and 20th centuries.[3]

In 1947, It was found that blood donations from a Hemophilia patient can cure clotting disorder in another Hemophilia patient. This was the start point to distinguish two major forms of Hemophilia which were later named A and B.

Classification

Hemophilia A and B and C are classified according to the amount of Factor VIII/ IX/ XI present respectively, resulting in either a mild, moderate, or severe form of the disease.[4]

Pathophysiology

Mainly, the pathogenesis of hemophilia A is characterized by genetic deficiency in Factor VIII. And similarly the pathogenesis of hemophilia B is characterized by genetic deficiency in Factor IX. Albeit, not all cases of Hemophilia are genetic disorders and there are several case reports of acquired forms of these diseases.

Causes

Hemophilia A and B are caused by an inherited X-linked recessive trait, with defective genes located on the X chromosome.

Differentiating Hemophilia from Other Diseases

Hemophilia must be differentiated from other diseases that cause abnormal or excessive bleeding.[5]

The most important differential diagnosis of Hemophilia A is that of hemophilia B or von Willebrand disease. The former is usually considered if factor VIII levels are normal in a person with a hemophilia phenotype. The latter is excluded on routine testing for that condition.

Epidemiology and Demographics

The incidence of Hemophilia A is approximately 1 per 5,000 to 10,000 males worldwide. In 2016, it was estimated that 20,000 males in the United States were living with Hemophilia A.The incidence of Hemophilia B is estimated 1 per 30,000 males.[6][1] The incidence of Hemophilia C is populations is estimated to be about 1:1,000,000 worldwide while it is much higher among Ashkenazi Jews (1:450)[2].

Risk Factors

Risk factors for development of Hemophilia include being of male sex and having a positive family history of the disease.

Screening

Screening for Hemophilia revolves around obtaining a thorough family history of bleeding.

Natural History, Complications, and Prognosis

  • Hemophilia presentation varies depending on the stage of the disease:[7]
    • People with mild hemophilia (5-40% of factor VIII/ IX activity in the blood) generally present with excessive bleeding following surgery (such as a dental procedure) or trauma. They may remain asymptomatic otherwise for long period of time, even into late adulthood
    • People with moderate hemophilia (1-5% of factor VIII/ IX activity in the blood) have presentation ranging between mild and severe forms. They present earlier than patients with mild hemophilia, and may bleed following minor trauma
    • People with severe hemophilia (less than 1% of factor VIII/ IX in blood) present sooner in life with abnormal bleeding episodes, usually in the first year of life. They are also at risk for spontaneous hemorrhages, i.e. unprovoked bleeding episodes, frequently in the joints and muscles

Natural History

Clinical features are usually related to abnormal or spontaneous bleeding, and can be separated into internal bleeds and external bleeds.[8] [9]

Complications

Many of the long-term sequelae of Hemophilia are either related to the morbidity of severe bleeds, or from side effects of frequent transfusions.

Prognosis

With appropriate assistance and education, patients with Hemophilia can live productive lives, both in terms of longevity and quality of life. The prognosis of these patients is helped greatly with the availability of more effective replacement therapy.

Diagnosis

Diagnostic Criteria

The initial phase of diagnosis is based on clinical findings of bleeding and a positive family history in majority of cases. The diagnosis may be suspected as coagulation testing reveals an increased partial thromboplastin time (PTT) in the context of a normal prothrombin time (PT) and bleeding time.[10] The diagnosis is made in the presence of very low (<10 IU) levels of factor VIII/ IX.

History and Symptoms

Hemophilia leads to a severely increased risk of bleeding from common injuries. Mild hemophilia is usually asymptomatic, unless the patient experiences an injury or undergoes surgery. Bleeding into large joints or muscles is the most common site of bleeding in hemophilia. Though uncommon, spontaneous or traumatic intracranial hemorrhages are the most catastrophic complication of hemophilia.

Physical exam findings in Hemophilia are usually related to the site of bleeding.[11]

Laboratory Findings

The typical coagulation profile of a patient with hemophilia A usually presents as the following:[12]

Other laboratory findings consistent with the diagnosis of hemophilia A include correction of the PTT with a 1:1 mixing study (i.e. factor VII/ IX from the normal blood mixed with the hemophiliac blood is able to correct for the coagulation deficit).

Imaging Findings

There are no imaging findings classically associated with Hemophilia.

Other Diagnostic Studies

Genetic testing appears to be a promising means of determining an individual's risk of attaining or passing on Hemophilia.

Treatment

There is no definitive treatment for hemophilia , the mainstay of therapy is supportive and preventative care. It is recommended that patients diagnosed with hemophilia be referred to hemophilia treatment centers (HTC), which provide coordinated care between physicians (usually hematologists), nurses, social workers and other staff who specialize in bleeding disorders.[13]

Medical Therapy

Most Hemophilia patients require regular supplementation with intravenous recombinant factor VIII/ IX, also known as replacement therapy. Apart from "routine" supplementation, extra factor concentrate is given around surgical procedures and after trauma, as well as emergently during any bleeding episode.[14]

Other therapeutic options include cryoprecipitate, fresh frozen plazma (FFP), desmopressin (DDAVP), and anti-fibrinoltytic agents.

Surgery

There is no role for surgery in the routine treatment of Hemophilia. Surgical intervention however may be requ ired in cases where hematomas or bleeds from the disease process cannot be managed conservatively, i.e. with major intracranial hemorrhages

Prevention

There are no established measures for the primary prevention of Hemophilia. Secondary prevention for hemophilia is aimed at preventing spontaneous or excessive bleeds in patients who are high risk, and relies on the use of recombinant clotting factor VIII/ IX administration on a regular basis to prevent bleeding episodes.

References

  1. 1.0 1.1 Zimmerman B, Valentino LA (2013). "Hemophilia: in review". Pediatr Rev. 34 (7): 289–94, quiz 295. doi:10.1542/pir.34-7-289. PMID 23818083.
  2. 2.0 2.1 Duga S, Salomon O (2013). "Congenital factor XI deficiency: an update". Semin Thromb Hemost. 39 (6): 621–31. doi:10.1055/s-0033-1353420. PMID 23929304.
  3. Franchini M, Mannucci PM (2012). "Past, present and future of hemophilia: a narrative review". Orphanet J Rare Dis. 7: 24. doi:10.1186/1750-1172-7-24. PMC 3502605. PMID 22551339.
  4. How is Hemophilia Diagnosed? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia/diagnosis. Accessed on July 30, 2016
  5. Konkle BA, Josephson NC, Nakaya Fletcher S. Hemophilia A. 2000 Sep 21 [Updated 2014 Jun 5]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016. Available from: http://www-ncbi-nlm-nih-gov.laneproxy.stanford.edu/books/NBK1404/
  6. What is Hemophilia? – NHLBI, NIH. Available at http://www.nhlbi.nih.gov/health/health-topics/topics/hemophilia. Accessed on Sept 20, 2016
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