What is the cause of microangiopathic hemolytic anemia

No matter who you are, you must pay attention to the understanding of microangiopathic hemolytic anemia, especially in the case of hypoxia or acidosis, which will reduce the deformability of red blood cells and cause vascular channel obstruction, mainly because of the formation of fibrinous microthrombi in the capillaries.

1. Fibrinous microthrombi are formed in the microvessels. The fibrin is in a network-like shape. When the circulating red blood cells stick to the network of fibrin threads, the continuous impact of blood flow causes the red blood cells to rupture.

2. Hypoxia and acidosis reduce the deformability of red blood cells, making them more susceptible to mechanical damage when forcefully passing through the fibrin mesh.

3. When fibrinous microthrombi are formed in the microcirculatory vessels (mainly capillaries), the blood flow channel is obstructed. At this time, red blood cells may pass through the cracks between the capillary endothelial cells of the lung tissue and other tissues to reach the tissues. The mechanical action when passing through the cracks can cause the red blood cells to twist, deform and rupture.

4. Acquired (or secondary) spherocytosis occurs when red blood cells are twisted, deformed, and ruptured. Due to surface tension, spherocytosis increases in fragility and is easily destroyed, resulting in hemolysis.

5. Some people have studied the mechanism of anemia formation in rabbit DIC caused by endotoxin, and believe that calcium influx increases due to the direct effect of endotoxin or the indirect effect of the coagulation-fibrinolysis-complement-kinin system, which affects membrane ion permeability or opens calcium channels.

At the same time, the calcium pump is inhibited, which increases the free calcium in red blood cells and activates a series of proteases and phospholipases, further damaging the membrane, changing its shape and increasing its hardness.

The results showed that the red blood cells were in a "pre-lytic state", suggesting that changes in the red blood cells themselves may be one of the important mechanisms of microangiopathic hemolytic anemia in DIC.