What is Aplastic Anaemia?
Aplastic Anaemia is a rare and life-threatening haematological disorder that predominantly affects children and young adults. The major causative mechanism is an immunological attack on one’s blood forming stem cells, known as haematopoietic stem cells, that leads to bone marrow destruction and bone marrow failure.
Aplastic Anaemia can develop either rapidly or slowly and there is no way to prevent its development. Sometimes, individuals with acquired Aplastic Anaemia also develop other disorders, such as paroxysmal nocturnal hemoglobinuria (PNH) or myelodysplasia (MDS).
What causes Aplastic Anaemia?
In most cases where a person is diagnosed with Aplastic Anaemia, the cause isn’t known. A number of chemicals, environmental toxins and viral infections have been implicated in precipitating Aplastic Anaemia, but in the majority of circumstances, there is no specific agent responsible for the immune system malfunction.
How is Aplastic Anaemia diagnosed?
There is no single definitive test to diagnose Aplastic Anaemia, rather it is a diagnosis of exclusion, with the inherited Bone Marrow Failure Syndromes among the main differential diagnoses.
Routine clinical assessments include reviewing the patient’s history, blood tests, and more invasive investigations procedures such as a bone marrow biopsy. A bone marrow biopsy is a surgical procedure which collects a small specimen of bone marrow tissue to review it’s functionality under the microscope.
Additional tests may be necessary to rule out other disorders such as leukemia and to determine if there is an inherited or genetic cause.
Severity of Aplastic Anaemia is determined by the number of one of the types of white blood cells (neutrophils) present and is classified as very severe, severe and mild.
What are the signs and symptoms of Aplastic Anaemia?
While Aplastic Anaemia can be present without symptoms, some people who have Aplastic Anaemia may experience:
- An increase in bruising
- Weakness, paleness
- Fatigue and tiredness
- Shortness of breath
- Increased infections
How common is Aplastic Anaemia?
Aplastic Anaemia is rare, affecting approximately 2-3 million people per year in North America and Europe, and approximately 5 per million per year in Southeast Asia.
What are the current treatments?
Based on the severity of Aplastic Anaemia (including factors of age and general health), treatments aim to cure the bone marrow failure and to treat the patient’s immediate signs and symptoms.
- Immunosuppressants– first line immunosuppressive treatments include anti-thymocyte globulin (ATG) and cyclosporin (CsA)
- Granulocyte colony stimulating factor(G-CSF) – a medication that stimulates the bone marrow to produce white blood cells (granulocytes) and blood forming stem cells (haematopoietic stem cells) and release them from the bone marrow into the blood stream
- Thrombopoietin receptor agonists(TPO mimetics) – Eltrombopag and Avatrombopag are medications that stimulate the production of platelets
- Androgens– sex hormone therapies are more likely to be used in older patients
- Bone marrow transplantation– the only current curative option available is bone marrow transplantation. In younger patients with a matched sibling donor, bone marrow transplantation may be considered as first line treatment in the setting of very severe or severe Aplastic Anaemia.