The Mechanism of Fever and its Clinical Management

Abstract

Vol: 1, Issue: 2 Fever is the most common symptom in clinical patients, and the pattern and time period of the fever can present the change of ill status, which could refer to its diagnosis, treatment and prognosis. In clinical, which is required to be treated not only by defining it on etiological, but also on symptomatic. Fever DefiningBody temperature depends on equilibrium between thermogenesis and thermolysis which is under control of thermoregulatory center; Preoptic-antihypophysis (POAH) is the highest part of thermoregulatory center which has secondary parts of medulla, pons, middlebrain and spinal cord. The set point of body temperature is scale of central body temperature by POAH [1]. Usually, 0.5°C over normal temperature is called fever, and most pathological etiology agent such as pyrogen and virals could raise the set point and cause fever. Mechanism of FeverThe mechanism of fever can be summarized as following: Effect of thermogenesis activators [2,3]Exogenetic pyrogen can stimulate production of endogenic pyrogen in body as activator, the activators include of endotoxin, exotoxin, bacteria or virus, and as well as inflammatory protein, lymphokine, antigen or antibody, all those can subsequently activate endogenetic pyrogen(EP) cells to produce and release endogenic pyrogen.EP has also named leukocytic pyrogen(LP), which is mostly produced and release by neutrophilic granulocyte, mononuclear cell, tissue macrophage or tumor cell. It is widely acknowledged that LP is interleukin firstly, then at lately time, more interferon, tumor necrosis factor and inflammatory protein have been found out to be in EP group. EP can take effect on macrophage cell in vascular area and following on inducing it to release fever activators by taking effect on POAH to thermogenesis response. Central MechanismSo far, it is difficulty to define the activated locus of EP, then most scientists think that EP is impossible to pass through blood-brain barrier, but it may ascend up the set point of body temperature by through central mediums in hypothalamus by PGE [4]. Response to thermoregulatory on ascending up of the set pointWhen the central body temperature is lower than the new level of the set point, the thermoregulatory will give order out to those thermogenesis and thermolysis organs, which will lead to fever by increasing thermogenesis and decreasing thermolysis. Clinical Presentation of FeverFever usually is caused by acute inflammation reaction by various etiology, the clinical presentations of it can be divided into three phases: Ascending phase of body temperatureThe central body temperature begins to rise rapidly or gradually as well; the faster process may reach the top temperature in several hours; and the slower one needs several days. In this ascend-up phase, patients may feel chilly or frigoris or skin pallescence. Children may lack of typical manifestation due to rapid ascension of their body temperature, but they usually present as lassitude, anorexia and dysphoris. Peak timeCorresponding to the rising lev...