FEVER [PYREXIA]
INTRODUCTION Fever is a common sign that can arise from many disorders. Fever is not itself a disease but the body's response to a disease. It is considered as one of the body's immune mechanism to attempt a neutralization of a perceived threat inside the body, be it bacterial or viral. A persistent high fever, though, represents an emergency. DEFINITION Fever is an elevation of body temperature mediated by an increase of the hypothalamic heat regulatory set-point. CONTROL MECHANISM OF BODY TEMPERATURE Human is "homoioterm" (has constant temperature). The Normal body temperature 37 o C within a narrow range of 1-1.5 o C. Circadian rhythm of body temperature - Early morning temperature is low and Highest level occurs at 4.00-6.00 PM Hypothalamic thermoregulatory center controls body temperature by Peripheral cold and warm neuronal receptors Temperature of blood circulating in the hypothalamus Heat generation Increased cell metabolism Muscle activity Involuntary shive...