Causes of fever

Fever is mainly caused by the action of pyrogens, which can increase body temperature. Everyone's normal body temperature is different. Fever is affected by many reasons and factors. There are many reasons for fever, which are mainly related to one's own conditions in daily life. At the same time, fever in daily life is mainly caused by direct effects on the body temperature center. The cause of fever is mainly caused by pyrogens.

It causes some pyrogenic effects on the body and also reflects a temperature regulation center. Fever itself is not a disease, but a symptom that usually occurs when you have a cold. The most common fevers that are easier to treat are those caused by bacterial, viral and fungal invasions, which increase the heat production of some diseases.

Fever is caused by the action of fever activators on the body, which in turn leads to the production of endogenous pyrogens (EP) and enters the brain to act on the body temperature regulation center, which in turn leads to the release of fever center mediators and causes changes in the set point, ultimately causing fever. Common fever activators include exogenous pyrogens from outside the body: bacteria, viruses, fungi, spirochetes, malarial parasites, etc.; and those from inside the body: antigen-antibody complexes, steroids, etc. Endogenous pyrogens (EP) come from EP-producing cells in the body, and their main types include: interleukin-1 (IL-1), tumor necrosis factor (TNF), interferon (IFN), interleukin-6 (IL-6), etc. EP acts on the body temperature regulation center located in the POAH, resulting in the production of positive and negative regulatory mediators. The latter may cause a change in the set point and ultimately lead to the generation of heat.

Fever itself is not a disease, but a symptom. In fact, it is one of the body's mechanisms for fighting infection. Fever may even have its uses: shortening the duration of illness, enhancing the effectiveness of antibiotics, and making infections less contagious. These abilities should offset the discomfort experienced when having a fever.

The etiology of fever of unknown origin (FUO) is a global problem, and the cause of nearly 10% of FUO cases remains unknown. Fever itself can be caused by many types of diseases, such as infection, tumors, autoimmune diseases and blood diseases, and cannot be clearly classified. In the past, such patients were usually diagnosed and treated by internal medicine physicians, and in most hospitals with more specialized specialties, they were mainly treated by respiratory physicians. Currently, many hospitals have opened infection departments and FUO is classified as such in the infection departments. This specialized management is an improvement and can improve the level of diagnosis and treatment. FUO has an accurate definition, which includes three key points: ① fever lasts ≥ 3 weeks; ② body temperature is > 38.3℃ for multiple times; ③ the diagnosis cannot be confirmed after ≥ 1 week of complete medical history, physical examination and routine laboratory tests. It can be seen that although FUO itself is a symptom diagnosis rather than a disease diagnosis, the diagnostic requirements are very strict.

The above causes of fever are due to the action of fever activators on the body and are also reflected in the body temperature regulation center. Fever itself is not a disease, but a symptom, which mainly occurs when you have a cold. The most common causes of fever are mainly caused by the invasion of bacteria, viruses and fungi, and some diseases that increase heat production. Make the infection less contagious, so good care should be taken in daily life.