What is the cause of high fever in human body?

Fever, also known as fever, is a pathological manifestation of the body, and we usually treat it as a symptom.

The same symptom has different causes, but there is a common ultimate mechanism leading to fever. Just like the Yangtze River and the Yellow River have countless mighty tributaries, there is only one final estuary.

Fever is the result of the common mechanism that the set point of human body temperature rises: when the set point of human body temperature rises, the normal maximum body temperature of 37.3 will no longer be regarded as normal by the body, and then the temperature considered as "normal" by the body can be reached by reducing heat dissipation and increasing heat production, just like boiling water at 100 degrees (1 standard atmospheric pressure). It may be necessary to use pressure cooker water 1.

The common cold (strictly speaking, it is an upper respiratory infection, so it is generally counted as an infection) and fever caused by infection are usually caused by two substances affecting the question regulation center in the brain: one is the substances contained in pathogens, such as peptidoglycan of bacterial cell wall and LPS of gram-negative bacteria, which are called exogenous heat sources; The other kind is like

It is said that pathogens stimulate the production of cells in vivo, which is called endogenous pyrogen. (There is also a special substance, which is produced by human body's own metabolism or autoimmune diseases, and can also cause fever, which is listed separately here for the time being).

However, there is also a case called central fever, which does not necessarily have pathogens: when the thermoregulatory center is damaged, including severe craniocerebral injury, it may also lead to an abnormal increase in body temperature, which is a situation that needs attention in clinical work and usually suggests that patients have a poor prognosis.