Reviewed July 15, 2004Rachid Baz, MD Department
of
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Figure 1 illustrates the current understanding of the coagulation cascade. |
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Coagulopathy of Liver Dysfunction Rare
Factor Deficiencies
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Hemophilias are most commonly X-linked recessive diseases characterized by deficiency of factor VIII (hemophilia A) or factor IX (hemophilia B, or Christmas disease).6,13 The clinical severity correlates well with factor levels, and they are clinically classified as mild (>5% of normal factor activity), moderate (1% to 5% factor activity), and severe (<1% factor activity). Coinheritance of the factor V Leiden mutation occurs in about 5% of patients and results in a decreased bleeding tendency.10 The incidence is 1 per 5,000 live births for hemophilia A and 1 per 30,000 live births for hemophilia B. In 30% of patients, hemophilia is the result of a de novo mutation, and no family history can be elicited. Males are most commonly affected; however, symptomatic females have been documented, and the proposed mechanisms include X chromosome inactivation or deletion, or the presence of a true homozygous offspring of an affected male and a carrier female.6,13
Prevention
This includes avoidance
of contact sports, good oral hygiene, careful immunization techniques,
institution of timely replacement therapy after trauma, and treatment
of acute bleeding episodes.3
Factor
Replacement: Choices Include Recombinant Versus Plasma-derived Factor
VIII Replacement
Plasma-derived concentrates vary in purity and undergo viral
inactivation procedures, rendering them safer.11-13 First-generation recombinant products (Bioclate, Helixate, Kogenate, Recombinate)
have demonstrated efficacy in clinical trials; however, they continue
to carry a theoretic risk of viral transmission because of the added human
albumin necessary for factor stabilization.5 Second-generation recombinant products (Kogenate FS and B-domain deleted
recombinant factor VIII [BDDrFVIII]) do not require albumin stabilization.4,11,13 Factor IX replacement has traditionally been with prothrombin complex
concentrates (PCCs) that contain factors II, VII, and X as well as IX,
and were associated with thrombotic risk.12,13,22 Newer plasma-derived factor IX concentrates are currently available, effective,
and undergo viral inactivation. Recombinant factor IX concentrates are
also available and effective and have no added albumin, hence eliminating
a theoretic risk of viral infection.22 The choice of replacement therapy depends on availability, safety, and
cost, with the knowledge that plasma-derived products are becoming safer
and recombinant products are less available and 2 to 3 times more costly.11-13 For patients with HIV, the use of recombinant products was associated
with a slower decline in CD4 cell count, and many experts recommend using
recombinant products in that setting. However, it is unknown if this advantages
translates into improved clinical outcome.6,12,13 In some European countries, previously untreated patients uniformly receive
recombinant products. The desired factor level depends on the site and
severity of bleeding: 30% to 40% factor activity is required for early
joint or muscle bleeding, 50% is required for dental surgery or more severe
muscle bleeding, and 80% to 100% for life-threatening or serious bleeding
(intracranial or intra-abdominal, or orthopedic surgeries).6,12,13 Because the half-life of factor VIII is about 12 hours and that of factor
IX 16 hours, factor levels should be checked every 12 hours and 16 hours,
respectively. When calculating the dose of replacement therapy, one should
keep in mind that one unit of clotting factor is the amount of clotting
factor contained in 1 milliliter of plasma.6,12,13 For example, if a patient with a plasma volume of about 3000cc and 1%
factor level needs to undergo dental surgery (which requires correction
to 50% of factor VIII level), 1500 units of factor VIII must be administered.
Primary prophylactic therapy has been shown to reduce the incidence of arthropathy. However, considerable controversy surrounding factor use remains, especially with regard to the age of onset of such therapy and the cost.21
DDAVP
DDAVP is the treatment of choice in patients with mild hemophilia A and
mild to moderate bleeding, but it has no role in hemophilia B.3
Antifibrinolytic
Therapy
Antifibrinolytic therapy (in the form of tranexamic acid or EACA) is useful
in controlling oral cavity bleeding and menorrhagia. For details on dosing,
refer to the section in this chapter on its use in patients with vWD.3,6
Treatment
of Long-Term Complications
Treatment of the long-term complications of hemophilia requires a multidisciplinary
approach. Chronic hemarthrosis may be managed with short-term prophylaxis
and at times requires synovectomy, which can be arthroscopic or via the
use of radioactive phosphorous.3,6,18,19 The treatment of patients with inhibitors to factor VIII with life-threatening
hemorrhage or in need of emergent surgery usually involves the use of
recombinant factor VIIa when available.9,23 For patients with inhibitors presenting with hemarthrosis, the use of
plasma-derived factor VIII bypassing products can be used.2,3,13 Finally, experimental treatments with gene-targeted therapies are currently
undergoing testing.16
Autoantibodies to VIII:C are characteristically oligoclonal non-complement-fixing IgG. Patients with lymphoproliferative disorders or multiple myeloma may have IgM or IgA antibodies. The incidence is 0.2 to 1 per million person-years with a higher incidence in older age groups. There is an equal gender distribution.8,30
Causes include connective tissue disorders (rheumatoid arthritis, systemic lupus erythematosus, myasthenia gravis, temporal arteritis, and pemphigus); drugs (penicillins, sulfa, alpha-interferon); malignancy (lymphoproliferative disorders, graft-versus-host disease, or prostate, renal, lung, and colon cancer); pregnancy (usually within 3 months of an uncomplicated primipara delivery); and idiopathic (especially in the elderly).8,30
It depends in part on the cause of the inhibitor. For drug-induced inhibitors, discontinuing the culprit drug will result in recovery within several months; most postpartum inhibitors will resolve within 2 to 3 months. For symptomatic patients, the treatment is aimed at managing the bleed and reducing the antibody titer. The latter involves immunosuppression (with steroids, Cyclophosphamide, or Azathioprine), biologic response modifiers (DDAVP), IVIG, or plasmapheresis.8,29,30 Prednisone at 1 mg/kg/day for 3 to 6 weeks is the treatment of choice and results in about a 30% response rate. For nonresponders to steroids, cyclophosphamide at 2 mg/kg/day for 6 weeks results in an added 30% response.8,29,30 Azathioprine has also been used as an immune suppressant. IVIG at 0.4 g/kg/day for 5 days results in a 25% to 30% response rate.8,29,30 It is used for patients with contraindications to immune suppression. Plasmapheresis can lower high-titer antibodies. It can be coupled with a staphylococcal protein A column (which attaches to the Fc portion of the antibody) and results in a 50% to 90% decrease in circulating antibodies. Disadvantages include cost, difficulty of performing it in unstable patients, the need for central venous access, and the potential for circulatory collapse with the use of staphylococcal protein A.8,29,30 The management of the bleeding patient includes factor replacement to overwhelm the antibody for low-titer antibody (<5 BU/mL), or the use of porcine factor VIII, activated thrombin complexes, or recombinant factor VIIa for patients with high-titer antibodies (as these patients would not respond to factor replacement in the form of VIII concentrates, FFP, or cryoprecipitate).8,29,30
- Blanchette
VS, Sparling C, Turner C. Inherited bleeding disorders. Baillieres
Clin Haematol. 1991;4:291-332.
- Batlle
J, Lopez MF, Brackmann HH, et al. Induction of immune tolerance with
recombinant factor VIII in haemophilia A patients with inhibitors. Haemophilia.
1999;5:431-435.
- Berntorp
E. The treatment of haemophilia, including prophylaxis, constant infusion
and DDAVP. Baillieres Clin Haematol. 1996;9:259-271.
- Berntorp
E. Second generation, B-domain deleted recombinant factor VIII. Thrombosis
& Haemostasis. 1997;78:256-260.
- Bray
GL, Gomperts ED, Courter S, Gruppo R, Gordon EM, Manco-Johnson M, Shapiro
A, Scheibel E, White G, 3rd, Lee M. A multicenter study of recombinant
factor VIII (recombinate): safety, efficacy, and inhibitor risk in previously
untreated patients with hemophilia A. The Recombinate Study Group. Blood.
1994;83:2428-2435.
- DiMichele
D, Neufeld EJ. Hemophilia. A new approach to an old disease. Hematol
Oncol Clin North Am. 1998;12:1315-1344.
- Goodeve
AC. Advances in carrier detection in haemophilia. Haemophilia.
1998;4:358-364.
- Hay
CR. Acquired haemophilia. Baillieres Clin Haematol. 1998;11:287-303.
- Hedner
U. Recombinant factor VIIa (Novoseven) as a hemostatic agent. Semin
Hematol. 2001;38:43-47.
- Lee
DH, Walker IR, Teitel J, Poon MC, Ritchie B, Akabutu J, Sinclair GD,
Pai M, Wu JW, Reddy S, Carter C, Growe G, Lillicrap D, Lam M, Blajchman
MA. Effect of the factor V Leiden mutation on the clinical expression
of severe hemophilia A. Thrombosis & Haemostasis. 2000;83:387-391.
- Lusher
JM. Recombinant clotting factor concentrates. Baillieres Clin Haematol. 1996;9:291-303.
- Mannucci
PM. The choice of plasma-derived clotting factor concentrates. Baillieres
Clin Haematol. 1996;9:273-290.
- Mannucci
PM, Tuddenham EG. The hemophilias--from royal genes to gene therapy. N Engl J Med. 2001;344:1773-1779.
- Martinowitz
UP, Schulman S. Continuous infusion of factor concentrates: review of
use in hemophilia A and demonstration of safety and efficacy in hemophilia
B. Acta Haematologica. 1995;94 Suppl 1:35-42.
- Nelson
MD, Jr., Maeder MA, Usner D, Mitchell WG, Fenstermacher MJ, Wilson DA,
Gomperts ED. Prevalence and incidence of intracranial haemorrhage in
a population of children with haemophilia. The Hemophilia Growth and
Development Study. Haemophilia. 1999;5:306-312.
- Pasi
KJ. Gene therapy for haemophilia. British Journal of Haematology. 2001;115:744-757.
- Pollmann
H, Richter H, Ringkamp H, Jurgens H. When are children diagnosed as
having severe haemophilia and when do they start to bleed? A 10-year
single-centre PUP study. European Journal of Pediatrics. 1999;158
Suppl 3:S166-170.
- Rodriguez-Merchan
EC. Therapeutic options in the management of articular contractures
in haemophiliacs. Haemophilia. 1999;5 Suppl 1:5-9.
- Rodriguez-Merchan
EC. Common orthopaedic problems in haemophilia. Haemophilia.
1999;5 Suppl 1:53-60.
- Shapiro
A. Inhibitor treatment: state of the art. Seminars in Hematology.
2001;38:26-34.
- van
den Berg HM, Fischer K, Mauser-Bunschoten EP, Beek FJ, Roosendaal G,
van der Bom JG, Nieuwenhuis HK. Long-term outcome of individualized
prophylactic treatment of children with severe haemophilia. British
Journal of Haematology. 2001;112:561-565.
- White
G, Shapiro A, Ragni M, Garzone P, Goodfellow J, Tubridy K, Courter S.
Clinical evaluation of recombinant factor IX. Seminars in Hematology. 1998;35:33-38.
- White
GC, 2nd, Courter S, Bray GL, Lee M, Gomperts ED. A multicenter study
of recombinant factor VIII (Recombinate) in previously treated patients
with hemophilia A. The Recombinate Previously Treated Patient Study
Group. Thrombosis & Haemostasis. 1997;77:660-667.
- White
GC, 2nd, Rosendaal F, Aledort LM, Lusher JM, Rothschild C, Ingerslev
J, Factor V, Factor IXS. Definitions in hemophilia. Recommendation of
the scientific subcommittee on factor VIII and factor IX of the scientific
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and Haemostasis. Thrombosis & Haemostasis. 2001;85:560.
- Mammen
EF. Coagulation abnormalities in liver disease. Hematol Oncol Clin
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- Bolton-Maggs
PH. Factor XI deficiency and its management. Haemophilia. 2000;6
Suppl 1:100-109.
- Gailani
D. Advances and dilemmas in factor XI. Curr Opin Hematol. 1994;1:347-353.
- Board
PG, Losowsky MS, Miloszewski KJ. Factor XIII: inherited and acquired
deficiency. Blood Rev. 1993;7:229-242.
- Knobl
P, Lechner K. Acquired factor V inhibitors. Baillieres Clin Haematol. 1998;11:305-318.
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