Summary about Disease
Acquired Hemophilia A (AHA) is a rare autoimmune bleeding disorder where the body's immune system mistakenly produces antibodies (inhibitors) that attack and neutralize clotting factor VIII (FVIII). This leads to impaired blood clotting and an increased risk of bleeding, despite not having a genetic predisposition to hemophilia. Unlike congenital hemophilia, which is present from birth, AHA develops later in life.
Symptoms
Symptoms of Acquired Hemophilia A are similar to those of congenital hemophilia, but can appear suddenly and be quite severe. Common symptoms include:
Unexplained and prolonged bleeding after injuries or surgery
Large, deep bruises (hematomas)
Muscle bleeds
Joint bleeds (hemarthrosis) – less common than in congenital hemophilia, but possible
Bleeding into the skin (purpura)
Nosebleeds (epistaxis)
Bleeding from the gums
Blood in the urine (hematuria) or stool (melena)
Postpartum bleeding (in women who have recently given birth)
Internal bleeding, which can be life-threatening.
Causes
The exact cause of acquired hemophilia A is often unknown (idiopathic) in about 50% of cases. However, some associated conditions include:
Autoimmune disorders: Such as rheumatoid arthritis, lupus, and inflammatory bowel disease.
Pregnancy and postpartum: AHA can develop during or shortly after pregnancy.
Malignancies: Certain cancers, particularly lymphoproliferative disorders (like lymphoma), are associated.
Medications: Certain drugs, such as sulfonamides, penicillin, and interferon-alpha, have been linked to AHA in rare cases.
Advanced Age: The elderly are more prone to developing AHA.
Medicine Used
Treatment for acquired hemophilia A focuses on two main goals: stopping the acute bleeding and eradicating the FVIII inhibitor.
For acute bleeding episodes:
Bypassing agents: These medications bypass the need for FVIII to promote clot formation. Examples include activated prothrombin complex concentrate (aPCC) and recombinant activated factor VII (rFVIIa).
Porcine Factor VIII: A version of factor VIII derived from pigs, which is less susceptible to human inhibitors.
To eradicate the inhibitor:
Immunosuppressive therapy: This is the mainstay of treatment to suppress the immune system and stop the production of FVIII inhibitors. Common medications include corticosteroids (e.g., prednisone), cyclophosphamide, rituximab, and azathioprine.
High-dose intravenous immunoglobulin (IVIg): Used in some cases, especially in combination with other immunosuppressants.
Is Communicable
No, acquired hemophilia A is not communicable. It is an autoimmune disorder and cannot be spread from person to person.
Precautions
Precautions for individuals with acquired hemophilia A focus on minimizing the risk of bleeding and managing the condition:
Avoid trauma: Take precautions to avoid injuries, especially head injuries.
Inform healthcare providers: Always inform doctors, dentists, and other healthcare providers about the condition before any procedure.
Medication awareness: Be aware of medications that can increase the risk of bleeding, such as aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs).
Monitor for bleeding: Be vigilant for signs of bleeding and seek prompt medical attention if any occur.
Follow treatment plan: Adhere strictly to the prescribed medication regimen and follow-up appointments.
How long does an outbreak last?
The duration of acquired hemophilia A varies significantly depending on the underlying cause, the severity of the bleeding, and the effectiveness of treatment. The inhibitor can be transient, especially when drug-induced, or persistent in cases linked to autoimmune diseases or malignancies. With effective immunosuppressive therapy, the inhibitor can be eradicated, leading to remission. However, relapse is possible. The acute bleeding phase can last from days to weeks until controlled with bypassing agents. Immunosuppression duration depends on the protocol and response, often lasting months to years.
How is it diagnosed?
Diagnosis of acquired hemophilia A involves:
Bleeding history: Assessing the patient's history of bleeding, including the onset, severity, and location of bleeding episodes.
Coagulation tests:
Prolonged activated partial thromboplastin time (aPTT): This is the most common initial finding. The aPTT measures the time it takes for blood to clot.
Mixing studies: Mixing the patient's plasma with normal plasma and repeating the aPTT. If the aPTT does not correct with mixing, it suggests the presence of an inhibitor.
Factor VIII assay: Measuring the level of factor VIII in the blood. In AHA, the FVIII level is typically low.
Inhibitor assay (Bethesda assay or Nijmegen-Bethesda assay): Detecting and quantifying the presence of FVIII inhibitors. A positive inhibitor assay confirms the diagnosis.
Testing for underlying conditions: Investigating potential underlying causes, such as autoimmune disorders, malignancies, or drug associations. This may involve blood tests, imaging studies, and consultation with specialists.
Timeline of Symptoms
The symptoms of acquired hemophilia A typically appear suddenly, unlike congenital hemophilia.
Onset: Bleeding can begin spontaneously or after a minor injury or procedure.
Initial symptoms: Often include large bruises, muscle bleeds, or unexplained bleeding from the gums or nose.
Progression: Bleeding can become more severe and widespread over days to weeks if left untreated, potentially leading to life-threatening complications.
Treatment response: With appropriate treatment, bleeding can be controlled within days to weeks, and the inhibitor can be eradicated over months to years.
Important Considerations
Rare disorder: AHA is a rare condition, and diagnosis can be delayed if healthcare providers are not familiar with it.
Underlying cause: Identifying and treating any underlying cause is crucial for successful management.
Prompt treatment: Rapid diagnosis and initiation of treatment are essential to control bleeding and improve outcomes.
Individualized treatment: Treatment plans should be tailored to the individual patient, considering the severity of bleeding, the level of the inhibitor, and any underlying conditions.
Monitoring: Close monitoring of FVIII levels, inhibitor titers, and treatment side effects is necessary.
Specialized care: Management of AHA often requires the expertise of hematologists and other specialists.
Patient education: Providing patients with comprehensive education about their condition, treatment options, and precautions is essential for self-management and adherence to therapy.