Pirogénicas

Pirogénicas refers to substances or conditions that cause fever. The term originates from the Greek words "pyr" meaning fire and "gennan" meaning to produce. When a pyrogenic substance enters the body, it can trigger an inflammatory response that leads to an increase in body temperature, commonly known as fever.

There are several types of pyrogenic agents. Exogenous pyrogens are external substances, such as bacteria, viruses, fungi, or their endotoxins. These can be introduced into the body through infection or contamination. Endotoxins, in particular, are potent pyrogens found in the cell walls of Gram-negative bacteria and are a frequent cause of fever during bacterial infections.

Endogenous pyrogens are substances produced by the body's own cells, primarily immune cells like macrophages and neutrophils, in response to infection or inflammation. These signaling molecules, also known as cytokines (such as interleukin-1, interleukin-6, and tumor necrosis factor-alpha), travel to the hypothalamus in the brain, which regulates body temperature. In the hypothalamus, they cause the release of prostaglandins, which then reset the body's thermostat to a higher temperature, resulting in fever.

Fever is a complex physiological response that can be beneficial in fighting infection by inhibiting the growth of some pathogens and enhancing immune system activity. However, excessively high fevers can be dangerous and require medical attention. The term pirogénicas is important in medical contexts, particularly in understanding the mechanisms of fever and the development of treatments for febrile illnesses and conditions associated with fever.