FEVER Friend or Foe? Or Both? Uptodate Evans, Nature Rev Imm, 2015 Kanneganti, Nature Rev Imm, 2010 Dr. Yıldıran

TEMPERATURE HOMEOSTASIS Fever is an abnormal elevation of body temperature that occurs as part of a specific biologic response that is mediated and controlled by the central nervous system. Body temperature is controlled by the thermoregulatory center of the hypothalamus. The thermoregulatory center balances heat production, derived primarily from metabolic activity in muscle and the liver, with heat dissipation from the skin and lungs. Dr. Yıldıran

TEMPERATURE MEASUREMENT Rectal thermometry –Rectal thermometry is contraindicated in patients with neutropenia. Oral thermometry – Oral thermometry generally is preferred in children who are old enough to cooperate. Oral temperature is typically 0.6°C lower than rectal temperature because of mouth breathing, which is particularly important in patients with tachypnea. Axillary thermometry – Axillary temperature is consistently lower than rectal temperature, but the absolute difference varies too widely for a standard conversion. Dr. Yıldıran

ELEVATED BODY TEMPERATURE Normal body temperature varies with age, time of the day, level of activity, and phase of the menstrual cycle, among other factors. Infants and young children generally have higher temperatures than older. In the newborn period (age 0 to 28 days), the mean normal temperature (measured rectally) is 37.5°C, with an upper limit of normal (ie, 2 standard deviations [SD] above the mean) of 38°C. Dr. Yıldıran

Relationship of hypothalamic set-point to body temperature Euthermia and Heat illness: hypothalamic set-point is normal, and body temperature approximates set-point and is also normal. Fever: hypothalamic set-point is elevated, and body temperature follows set-point and is also elevated. Dr. Yıldıran

INFECTION/INFLAMMATION   INFECTION/INFLAMMATION  The fever response is a hallmark of infection and inflammatory disease. four cardinal signs of inflammation Heat (calor) Pain (dolor) Redness (rubor) Swelling (tumor) Fever occurs at a high metabolic cost, such that a 1 °C rise in body temperature requires a 10–12.5% increase in metabolic rate. Dr. Yıldıran

BENEFIT/ HARM Potential benefits of fever include Potential harms   BENEFIT/ HARM  Potential benefits of fever include retardation of the growth and reproduction of some bacteria and viruses enhanced immunologic function at moderately elevated temperatures Potential harms Fever can make patients uncomfortable. increased metabolic rate, Increased oxygen consumption, increased carbon dioxide production, Increased demands on the cardiovascular and pulmonary systems. Dr. Yıldıran

INFECTION/INFLAMMATION   INFECTION/INFLAMMATION  Dr. Yıldıran

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  IN FEVER Dr. Yıldıran

FEVER vs HYPERTHERMIA FEVER HYPERTHERMIA   FEVER vs HYPERTHERMIA  FEVER HYPERTHERMIA Change in hypothalamic set point Involves cytokines There is diurnal variations Rarely exceeds 41 C Complications are rare Failure in thermoregulation Can exceed >41 C Can be detrimental Absence of diurnal variation Dr. Yıldıran

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  APPLE VINEGAR  Dr. Yıldıran

MANAGEMENT Anticipatory guidance   MANAGEMENT  Anticipatory guidance  Patients, parents, and other caregivers frequently make the decision to treat fever without consulting a healthcare provider. Many patients and caregivers believe that fever is harmful and that temperature elevation requires treatment regardless of its cause or effects Dr. Yıldıran

MANAGEMENT Fever is not an illness, but a physiologic response.   Fever is not an illness, but a physiologic response. In otherwise healthy children, most fevers are self-limited and benign, fever does not cause brain damage. There is no evidence that fever makes the illness worse. PO/IV Fluid replacement decreases fever. An antipyretic agent does not help to determine whether the child has a bacterial or viral infection. Antipyretic medications should not be given combination cough and cold preparations (PLUS), which often contain antipyretic medications; giving both medications may lead to inadvertent overdose. Dr. Yıldıran

ANTIPYRETICS    Indications for the short-term treatment of fever may include: Shock Underlying neurologic or cardiopulmonary disease, or other condition with increased metabolic rate (eg, burn, postoperative state) Alteration in fluid and electrolyte balance High fever (ie, ≥40ºC [104ºF]) Discomfort Major head trauma Post-cardiac arrest Dr. Yıldıran

ANTIPYRETICS    Acetaminophen generally is not recommended for infants younger than three months of age. The dose of acetaminophen is 10 to 15 mg/kg per dose (maximum dose 800 mg to 1 g) orally every four to six hours (with no more than five doses in a 24-hour period) with a maximum daily dose of 75 mg/kg per day up to 4 g/day. Dr. Yıldıran

ANTIPYRETICS    We suggest ibuprofen as the initial antipyretic agent when antipyretic and anti-inflammatory activity are desired (eg, in children with juvenile arthritis). The dose of ibuprofen is 10 mg/kg per dose (maximum dose 600 mg) orally every six hours with a maximum daily dose of 40 mg/kg up to 2.4 g/day. Ibuprofen generally is not recommended for infants younger than six months. Such infants have limited renal function relative to older infants and children. Dr. Yıldıran