In case of haemolytic anemia, there is hemolysis, that is to say the premature destruction of red blood cells whose normal life span is 120 days.
If the bone marrow fails to compensate for this destruction by increasing the production of blood cells, anemia will appear. This anemia may be more or less acute depending on the rate of destruction (= lysis) of red blood cells.
This destruction can be due either to an attack of the globules, or to an abnormal fragility of these red blood cells. In fact, there are different types of hemolytic anemia:
Acute haemolytic anemias:
- Haemolytic disease of the newborn: the mother makes antibodies against fetal erythrocytes.
- Lederer-Brill anemia (or acute febrile anemia): it affects children especially after an ENT infection, for example.
- Some infections, parasitoses or poisoning can also destroy red blood cells.
Chronic hemolytic anemias:
> Constitutional or congenital:
- Minkowski-Chauffard disease (or hereditary spherocytosis): Excessive fragility of the red blood cell membrane causes premature spontaneous destruction. There are other more rare abnormalities of the red blood cell membrane.
- Thalassemia: in its major form, there is abnormal weakening of red blood cells responsible for hyper-destruction.
- Sickle cell anemia or sickle cell anemia: in this case also, the red blood cells have a particular fragility, inherent to their sickle-shaped appearance.
- Enzyme hemolytic anemia: this is a decrease or absence of certain enzymes necessary for the survival of red blood cells (G6PD or hexokinase, for example).
> Acquired:
- They may be of immunological origin (autoimmune haemolytic anemia), infectious (certain viruses or parasites such as malaria) or toxic (certain drugs, snake venom, certain fungi).
- They can be of mechanical origin: cardiac valve prostheses for example, in contact with which the red blood cells burst.
- Marchiafava-Micheli disease (nocturnal paroxysmal haemoglobinuria: there is an extreme fragility of the red blood cells due to an exceptional mutation of a gene that leads to a lack of protection of the membranes of erythrocyte cells.This is a very rare disease - less 1, 000 cases in France).
