What happens in the bone marrow
Normally, the bone marrow is a factory where stem cells continuously produce red blood cells, white blood cells and platelets. With aplastic anemia, the number of stem cells drops sharply, and the hematopoietic tissue is replaced by fatty tissue: upon biopsy, the brain looks empty. Most often, this is the result of an autoimmune process when T lymphocytes recognize stem cells as foreign and destroy them. Less commonly, the cause is direct toxic damage or congenital defects in DNA repair. Since the common precursor of all cells is affected, deficiency develops along all lines simultaneously.
- Depletion of hematopoietic bone marrow tissue
- Replacement with adipose tissue
- Autoimmune attack on stem cells
- Simultaneous drop of all blood cells
- Congenital forms in children and adolescents
Causes and risk factors
In approximately most cases, a specific cause cannot be determined, and the disease is called idiopathic. Known provoking factors are contact with benzene and organic solvents, insecticides, ionizing radiation, and certain medications. Aplastic anemia can develop after viral hepatitis, as well as during pregnancy. In children and young people, hereditary syndromes with impaired DNA repair occur, in which aplasia is combined with appearance features and developmental defects.
- Idiopathic form - most cases
- Benzene, solvents, insecticides
- Ionizing radiation
- Selected medications
- Past viral hepatitis
- Hereditary bone marrow failure syndromes
Symptoms
Complaints consist of three groups and appear gradually. Anemic syndrome - pallor of the skin and mucous membranes, weakness, dizziness, shortness of breath and palpitations during normal exercise. Hemorrhagic syndrome - bruises from the slightest touch, pinpoint hemorrhages on the skin, bleeding gums, nosebleeds and heavy menstrual bleeding. Infectious syndrome - recurring sore throats, stomatitis, pneumonia, poorly healing wounds and fever without an obvious focus. There is usually no enlargement of the lymph nodes, liver and spleen in aplastic anemia, and this is an important diagnostic detail.
- Pallor, weakness, shortness of breath on exertion
- Bruises and pinpoint rashes on the skin
- Bleeding gums and nosebleeds
- Frequent and persistent infections
- Fever without obvious focus
- No enlargement of the spleen and lymph nodes
Diagnostics
The starting point is a general blood test with the calculation of the leukocyte formula and reticulocytes: the combination of low counts of all sprouts with reduced reticulocytes indicates that the bone marrow is not working, and not the cells are being destroyed in the periphery. The diagnosis is confirmed by bone marrow examination: aspiration and necessarily trephine biopsy, which shows tissue devastation. Additionally, leukemia, myelodysplastic syndrome, deficiency of vitamin B12 and folic acid, viral infections, and in young people, hereditary syndromes are excluded. Cytogenetic testing helps distinguish aplasia from myelodysplasia.
- General blood test with leukemia formula
- Reticulocytes
- Core biopsy and bone marrow aspirate
- Cytogenetic study
- Vitamin B12, folic acid, ferritin
- Screening for viral hepatitis and HIV
Treatment and lifestyle
The choice of tactics depends on the severity, age and availability of a suitable donor. Young patients with a severe form and a compatible related donor are offered a bone marrow transplant, which gives a chance for complete restoration of hematopoiesis. In the absence of a donor or at an older age, immunosuppressive therapy is used to suppress the attack of lymphocytes, sometimes in combination with stimulators of platelet formation. Throughout treatment, supportive measures are necessary: transfusions of red blood cells and platelets, immediate treatment of infections, prevention of bleeding. Treatment is carried out only by a hematologist.
- Bone marrow transplantation with a suitable donor
- Immunosuppressive therapy
- Hematopoietic stimulants
- Transfusion of red blood cells and platelets
- Early treatment of any infection
- Avoid trauma, dental floss and hard brushing if platelets are low
- Avoid contact with solvents and paints