Aplastic Anemia: Information on Causes, Diagnosis & Treatments
Aplastic Anemia (blood marrow failure) is a blood disorder that affects bone marrow by not producing sufficient numbers of red blood cells, white blood cells, and platelets to meet the body's needs. The disorder is the result of damaged bone marrow stem cells. The disease primarily affects young adults and children. However, every individual is susceptible to the disorder at any age.
Marrow is a spongy tissue on the interior bones that create all blood cell lines including platelets, white cells and red cells that provide nourishment, supply oxygen, fight infections, and clot the blood. During normal function, new cells mature, reproduce and eventually die off leaving new healthy blood cells that have been formed in bone marrow. People experienced aplastic anemia do not produce adequate new cells in their bone marrow which leaves their body highly susceptible to infection and uncontrollable bleeding.
- What Causes Aplastic Anemia?
- Who Is at Risk for Aplastic Anemia?
- Common Symptoms
- Diagnosing Aplastic Anemia
- Aplastic Anemia Treatments
What Causes Aplastic Anemia?
Aplastic anemia can be inherited (genetic predisposition) or acquired. The acquired disorder is thought to be the result of an attack on the hematopoietic progenitor cells by the body's immune system. It is these stem cells that develop into the 3 different forms of blood cells.
Those who inherit aplastic anemia typically display the first signs and symptoms before their tenth year. Research studies show that most severe aplastic anemia cases involve an autoimmune disorder where the immune system attacks organs and tissues.
Who Is at Risk for Aplastic Anemia?
While anyone can develop aplastic anemia, children who are predisposed to the condition are most likely to develop the disorder. Additionally, people that are highly susceptible to acquiring aplastic anemia have been exposed to environmental factors including radiation, chemicals, drugs, and viruses that are known to trigger the body's immune system to attack bone marrow stem cells. That said, aplastic anemia is an idiopathic disorder meaning scientists and doctors to yet to identify its exact cause.
Patients who inherit aplastic anemia typically inherited a genetic mutation from a parent that involved Fanconi anemia, dyskeratosis congenita, Schwachman-Diamond Syndrome, or Diamond-Blackfan anemia.
Individuals most likely to acquire aplastic anemia are those that participate or are exposed to certain factors including:
- Radiation and chemotherapy to treat cancer
- Pesticides, arsenic, benzene and other toxins used in chemical synthesis and manufacturing processes
- Autoimmune disorders including rheumatoid arthritis and lupus erythematosus
- Viral infectious diseases including HIV, hepatitis, and Epstein-Barr virus
- Certain medications including immunosuppressants, antibiotics, and NSAIDs (nonsteroidal anti-inflammatory drugs)
- Bone cancer sufferers
Different patients suffer varying symptoms based on the severity of the disorder and the quantity of each type of blood cell (white, red, and platelet) that might be normal levels or much lower than normal levels. Some of the symptoms associated include:
- Unexplained Infections that develop when the body has fewer white blood cells to fight off foreign invaders
- Fatigue caused by fewer than normal red blood cells in the body
- Unexpected and Uncontrollable Bleeding that is the result of fewer platelets in the bloodstream that have natural blood clotting properties
Other common aplastic anemia symptoms associated with the disorder involve:
- Significant overall weakness or fatigue
- Shortness of breath
- Fever caused by infection
- Flu-like symptoms
- Recurring infection
- Small red rashes that appear on the skin indicating epidermis bleeding
Diagnosing Aplastic Anemia
Doctors often identify the condition based on abnormalities that appear in laboratory testing results in patients who have not experienced the common symptoms associated with the disorder. This is important because severe cases of aplastic anemia require immediate medical attention.
A formal diagnosis of bone marrow failure disorder requires a comprehensive examination of bone marrow cells in blood is viewed under a microscope. Accurate test results require an extensive blood makeup that is acquired by biopsies and bone marrow aspiration procedures. The removal of bone marrow samples from the hipbone using a special needle while the patient is under anesthesia can help verify the number of platelet blood clotting cells, neutrophils (white cells), and reticulocytes (regenerating red cells).
The doctor may also perform a kidney function study and recommend other laboratory blood tests to rule out the need to treat the condition with immune system compatible marrow and blood products.
Before any treatment for aplastic anemia is recommended, the doctor will classify the disorder by conclusive results of bone marrow biopsies and blood tests. The patient's disorder may be classified as very severe, severe, or moderate. Only very severe cases will involve aggressive treatment.
Aplastic Anemia Treatments
The type of treatment that a doctor will recommend for aplastic anemia is based on the severity of the disorder., Treatments involve immune-suppressing therapies and bone marrow (stem cell) transplants in severe cases. This treatment can be beneficial, especially for individuals who are 40 years or younger and have a sibling whose blood type matches the patient.
Even though aplastic anemia is not a formal cancer, doctors often treat the condition using therapies that are highly similar to the treatments used for lymphomas, leukemias, and other blood-forming cancers.
The most common options for treating or curing aplastic anemia involve:
- Blood Transfusion – Typically, doctors will recommend platelet transfusions to treat aplastic anemia in individuals who have a severe deficiency of platelet blood cells. This procedure reduces the potentially elevated risk of suffering a fatal hemorrhage due to uncontrollable bleeding. The doctor might recommend a red blood cell transfusion to treat associated symptoms including shortness of breath and intense fatigue. Usually, blood transfusions quickly stabilize patients suffering from the disorder. However, it is not considered a long-term solution by itself.
- Bone Marrow Transplantation – Transplanting bone marrow is found to be highly effective at treating severe cases of aplastic anemia. To accomplish this, the doctor will destroy nonfunctioning bone marrow cells using radiation or medications and replace the damaged tissue with bone marrow acquired from a compatible donor who could be a sibling, parent, or grandparent. Younger patients and donors are the best candidates for a successful outcome. Alternative donors of a bone marrow transplant that are either mismatched or unrelated to the patient are typically only recommended in severe cases where the patient did not positively first respond to immunosuppressive medication therapy.
- Medical Therapy – In many cases, bone marrow transplantation is not a viable option based on finding a compatible donor, health related issues, or age. Doctors can still recommend drug therapy using cyclosporine and ATG (anti-thymocyte globulin). However, nearly one out of every two patients undergoing medical therapy will develop other blood associated disorders and malignancies will have a relapse of their condition.
- Supportive Care – Long-term follow-up and intensive support care are crucial to managing aplastic anemia. Some patients require frequent infused medications and transfusions through a central venous catheter that delivers the medical products through a vein in the chest. To avoid or correct cardiopulmonary complications, the patient might need urgent support within fused red blood cell and platelet products to eliminate fatigue or prevent spontaneous bleeding.
Many severe cases involving aplastic anemia worsen due to a bacterial or fungal infection that could claim the life of the patient. These individuals often require extensive antibiotic therapies or undergo treatments involving antifungal or antiviral agents.