Cholesterol is transported through our body in two vesicles: HDL and LDL. That’s why we talk about LDL cholesterol (the bad one) and HDL cholesterol (the good one).
The ideal is to have both types of cholesterol in normal ranges. Although high LDL cholesterol is dangerous, extremely low levels also have consequences. The same happens if HDL cholesterol or other types of fats increase, such as triglycerides (hypertriglyceridemia)
Familial hypercholesterolemia encompasses all those disorders in which cholesterol levels increase. There are pathologies in which HDL cholesterol increases, although they are less frequent. For this reason, from now on we are going to talk about diseases that occur with an increase in LDL cholesterol.
The problem is that an excess of LDL cholesterol is harmful to our body, as it accumulates and hinders the normal functioning of the body.
The main pathology related to high cholesterol levels is This disease is a disorder of the blood vessels by the formation of plaques that diminish their light, altering the passage of blood.
Why is familial hypercholesterolemia occurring?
The cholesterol that we ingest with the diet is absorbed in the intestine next to that which comes from the bile, juice synthesized in the liver for digestion. When absorbed, it passes into the blood in high density cholesterol or LDL cholesterol vesicles.
Through the bloodstream it reaches the liver, where it binds thanks to the LDL receptor and enters the organ. There, it is metabolized so that it goes to different parts of the body to fulfill its functions.
In familial hypercholesterolemia there is a mutation in the gene that synthesizes the LDL receptor. This produces that the liver can not internalize the cholesterol and for that reason the levels of the same are high in the blood. There are also other related disorders where those that are elevated are another type of lipids, triglycerides.
In other cases, the mutation affects other genes. This alteration does allow the receiver to be synthesized but not work properly. Depending on the mutation the levels will be higher or lower, there are also other factors that determine the severity of the pathology.
Consequences of familial hypercholesterolemia
As cholesterol can not enter the liver it accumulates in other tissues. This produces deposits of fat:
When they appear on the skin they are called They appear mainly in the joints, such as the elbow or knee. They are soft lumps that have no meaning but may serve to suspect the pathology.
They are white-yellowish plates of different sizes. They are formed because the macrophages of the skin and tendons, cells of the immune system, try to digest the lipids and accumulate. Fat-laden macrophages are called foam bodies.
The deposits of fat in the eyelids are called xanthelasmas . They are similar to xanthomas, benign eyelid tumors. They can also be present in other metabolic disorders such as .
These findings serve to suspect and diagnose the disease, although they are not serious. The main problem with high cholesterol levels is its effect on the vessels.
The LDL cholesterol vesicles, along with other substances accumulate in the wall of the arteries. Over time, plates with these substances, called atheromatous plaques, form in the vessels. It also hardens the vessel wall, which becomes less flexible when blood passes. It is what is known as atherosclerosis.
This can end up narrowing the light of the arteries, making it difficult for blood to pass through. When an artery becomes blocked, the blood does not reach the tissues that depend on it.
This can cause cells to die, is called necrosis, and is what is called infarction. Depending on the territory that runs out of blood, it refers to (heart muscle), cerebral infarction …
For this reason, high blood cholesterol levels favor heart attacks at an early age. Other factors are also involved, such as smoking or metabolic disorders, such as diabetes.