Can children's allergies cause fever?

In fact, most cases of allergies will not cause fever, unless the allergy is caused by a viral infection or a bacterial infection. If this is the case, a fever may occur. This situation will become more common in children, so if it occurs, parents should give them medication in time to relieve the symptoms.

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, which in turn causes a change in the set point and ultimately causes 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 a precise definition, which includes 3 key points:

① Fever lasts for ≥ 3 weeks;

②Body temperature > 38.3℃ for many 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.