What is Aplastic Anemia?
Aplastic anemia is a condition characterized by chronic failure of the body’s blood cell production due to damage, resulting in a decrease or absence of the blood-forming cells in the bone marrow. This circumstance consequently leads to pancytopenia, a medical condition where there is a reduction in the number of all types of blood cells.
What Causes Aplastic Anemia?
Bone marrow can get damaged in many different ways. The most common reason, known as ‘idiopathic’, is unexplained and accounts for 65% of all cases. Fanconi anemia, a hereditary condition, is another common cause. This usually shows up in late childhood and can cause decreased blood cell counts, underdeveloped organs, and abnormalities in bone formation such as unusual forearm bones, absence of thumbs, and short height.
Seronegative hepatitis, a type of liver inflammation, is responsible for 5% to 10% of all cases. Faulty telomerase, enzymes that help cells reproduce, are involved in 5% to 10% of adult cases of severe lack of blood cells. Additionally, there are some extremely rare connections to bone marrow injury, such as a skin and tissue inflammation condition called eosinophilic fasciitis.
Risk Factors and Frequency for Aplastic Anemia
The data on how often aplastic anemia occurs is not very clear. However, research suggests that there may be around 0.6 to 6.1 cases for every million people. This estimate comes mostly from looking back at recorded deaths. The condition can happen to anyone, regardless of age or sex, with an equal chance for males and females. Still, it tends to occur slightly more often in children and people aged 20 to 25.
- Data on aplastic anemia occurrence is unclear.
- Research estimates 0.6 to 6.1 cases per million people.
- This estimate is based on past death records.
- Aplastic anemia can affect all age groups and both genders equally.
- However, it’s slightly more common in children and people aged 20 to 25.
Signs and Symptoms of Aplastic Anemia
Aplastic anemia can occur in anybody, regardless of age, gender, or race. This condition causes a variety of symptoms that are related to the loss of blood cell types in the body. People with this disorder may experience symptoms of anemia, such as tiredness, pale skin, and difficulty breathing. It can also result in frequent minor infections or sudden fevers, due to lowered white blood cell count. Further, a reduction in platelets might lead to easy bruising, bleeding of the gums, and small red spots on the skin. An enlarged spleen is not associated with aplastic anemia, so if this is observed, another diagnosis might be more appropriate. Lab tests will usually reveal a certain type of anemia along with low white blood cell and platelet counts. However, there shouldn’t be any abnormal cells present, as this can signal a different blood disorder.
- Tiredness
- Pale Skin
- Difficulty Breathing
- Frequent minor infections or sudden fevers
- Easy bruising
- Bleeding of the gums
- Small red spots on the skin (petechiae)
Testing for Aplastic Anemia
Aplastic anemia is a medical condition where your bone marrow doesn’t make enough new blood cells. It’s diagnosed based on certain criteria, such as a lack of bone marrow cells and two or more low blood cell counts. These can include less than 1% or less than 40,000 reticulocytes per microliter, fewer than 500 neutrophils per microliter, or less than 20,000 platelets per microliter.
The severity of the disease is gauged by how few cells are in your bone marrow. For instance, if less than 30% of your bone marrow is cellular, your disease may be considered moderate. If there are less than 25% cells or less than 50% cells with fewer than 30% blood-forming cells, the disease is classified as severe. The disease becomes very severe if it meets the criteria of severe and there are fewer than 200 neutrophils per microliter.
Medical experts accomplish these tests by taking a sample of your bone marrow; however, it could be challenging if the marrow is not yield enough (“dry tap”). That’s why a biopsy of the bone marrow is crucial as it can show a significant decrease in cells and the absence of marrow progenitors.
Additionally, genetic tests like flow cytometry and fluorescence in situ hybridization (FISH) are used to rule out blood cancers that could be causing a decrease in all blood cells. Depending on what’s causing the bone marrow failure, other tests may be needed, like checking for a mutation in the telomerase gene if dyskeratosis congenita is suspected.
Treatment Options for Aplastic Anemia
The treatment of aplastic anemia, a condition where your body stops producing enough new blood cells, depends on the root cause. If the condition is triggered by a particular medication or substance, the first step is to stop using it. In fact, some drugs have even been removed from the market in the U.S. due to their links with aplastic anemia.
In some cases, like when aplastic anemia is associated with pregnancy, the condition clears up by itself after childbirth. Patients with a tumor in their thymus gland (thymoma) usually see their bone marrow fully recover after the tumor is removed.
If no reversible cause is found, the treatment approach may vary based on the patient’s age, how severe their disease is, whether they have a potential donor for hematopoietic cell transplant (HCT), and their overall health. Typically, younger patients (under 50 years old) in good health with severe disease should try HCT before starting immunosuppressive therapy. Older patients (50 years or older) in good health, and young patients who don’t have a potential HCT donor, should receive a full-dose immunosuppressive therapy with a combination of drugs. This therapy can be adjusted according to the person’s health condition.
The drugs used in this therapy are eltrombopag, anti-thymocyte globulin (ATG), cyclosporine A, and prednisone. Eltrombopag helps to increase platelet counts and stimulate the production of marrow progenitor cells. ATG eliminates T-cells that react to antigens and can help manage the symptoms of aplastic anemia. Cyclosporine A inhibits the production and release of a protein called interleukin-II which stimulates T-cells. Prednisone promotes the death of immature lymphocytes.
Patients also receive supportive care to prevent and treat infections, and to manage blood transfusions. Iron chelators may be given to control secondary hemochromatosis, a condition caused by excess iron in the body. It’s not recommended to use growth-factors as there won’t be enough precursor cells to generate an adequate response.
Survival rates rely on factors like age, disease severity, and the effectiveness of the initial therapy. Those who recover after stopping a drug or treating the underlying causes usually lead a stable life. The 5-year survival rate for those who undergo a bone marrow transplant from a suitable donor is more than 75%. However, most patients that are not treated die within a year due to complications such as bleeding, infections, or progression to lymphoproliferative disorders, which are conditions that cause your body to produce too many lymphocytes, a type of white blood cell.
What else can Aplastic Anemia be?
Pancytopenia, a condition characterized by a decrease in all types of blood cells, could result from a syndrome referred to as myelophthistic syndrome. This syndrome effectively takes over the normal bone marrow. This condition could be caused by:
- Metastases from solid tumors, often seen in lung, breast, and prostate cancers
- Types of neoplasms such as acute myelogenous leukemia
- Myelofibrosis, a rare bone marrow cancer
- Hemophagocytic lymphohistiocytosis, a disease of the immune system
- Osteopetrosis, a genetic disorder affecting bone density
- Gaucher disease, a genetic disorder causing a buildup of harmful substances in organs and tissues
In such cases, a bone marrow biopsy would show traces of the underlying disease rather than reduced cell production.
On the other hand, it’s also common to see a decline in just one type of blood cell – such as in agranulocytosis (reduced white blood cells) and pure red cell aplasia (reduced red blood cells). These conditions often share similar causes with aplastic anemia (a disease where the body stops producing enough new blood cells). In these cases, the symptoms will relate to the specific type of blood cell affected.
What to expect with Aplastic Anemia
The chances of surviving aplastic anemia depend mostly on the patient’s age, how severe the disease is, and whether the initial treatment is successful. Patients who get better after stopping certain medication or treating an underlying condition usually have a stable path to recovery, just like those who have diseases that resolve on their own.
If patients receive a bone marrow transplant from a suitable donor, there is a more than 75% chance that they will survive for another five years. However, it’s important to note that without any treatment, most individuals will likely die within a year due to complications from the disease, such as bleeding, infections, or the disease changing into lymphoproliferative disorders, which are conditions affecting the body’s ability to fight diseases.
Possible Complications When Diagnosed with Aplastic Anemia
Some of the frequent complications of aplastic anemia are increased bleeding, further infections, and potential evolution towards conditions characterized by excessive lymph cell growth. Management of these problems typically involves regular monitoring and treatment of symptoms. This might involve antibiotics to combat infections, chemotherapy to control abnormal cell growth, and transfusions to replace lost blood.
Common Complications and Their Management:
- Bleeding (Managed with transfusions)
- Infections (Managed with antibiotics)
- Transformation to lymphoproliferative disorders (Managed with chemotherapy)
Preventing Aplastic Anemia
Aplastic anemia is a health condition where the body can’t produce blood cells that are critical for functions like fighting infections, carrying oxygen, and repairing damaged tissues. The reason behind this disease varies widely, and in many cases, the exact cause remains unknown.
Patients with known causes or those whose disease resolves on its own typically have a great chance at recovery. Treatment options can include a bone marrow transplant or taking specific medications that provide the body with blood products it needs.
However, it’s important to closely monitor for any complications related to the disease, like bleeding, cancers, or infections. Any changes should be immediately reported to the healthcare professional for appropriate attention.
