Dr.Azad A Haleem AL.MezoriUniversity Of DuhokCollege of Medical

Pediatrics Department

Fever in children

Background

• Feverish illness in children: • is the most common reason for children to be

taken to the doctor• is a cause of concern for parents and carers• Fever occurs in response to infection, injury, or

inflammation and has many causes. • can be a result of a simple self-limiting

infection or a life-threatening disorder.

DEFINITION OF FEVER

• Fever is an elevation of body temperature that exceeds the normal daily variation, in conjunction with an increase in hypothalamic set point.• Fever is defined as a before-noon

temperature of more than 37.2°C or an after-noon temperature of more than 37.7°C .

Important Notes • Fever without localizing signs (without a focus),

frequently occurring in a child younger than 3 years old, in which a history and physical examination fail to establish a cause, although a diagnosis of occult bacteremia may be suggested by laboratory studies

• Fever of unknown origin (FUO), which defines fever for more than 14 days without an identified etiology despite history, physical examination, and routine laboratory tests or after 1 week of hospitalization and evaluation.

• Fever can be classified depend on whether it has lasted 7 days or less (acute) or more than 7 days (chronic).

Important Notes

• Bacteremia is defined as a positive blood culture and may be primary or secondary to a focal infection.

• Sepsis is the systemic response to infection that is manifested by hyperthermia or hypothermia, tachycardia, tachypnea, and shock.

• Children with septicemia and signs of CNS dysfunction (irritability, lethargy), cardiovascular impairment (cyanosis, poor perfusion), and disseminated intravascular coagulation (petechiae, ecchymosis) are readily recognized as toxic appearing or septic.

Pathophysiology

• Core body temperature is normally maintained within 1°C to 1.5°C in a range of 37°C to 38°C.

• Normal body temperature is often considered to be 37°C .

• Rectal temperatures greater than 38 °C (>100.4°F) generally are considered abnormal.

VARIATION IN TEMPERATURE• There is normal diurnal variation, with maximum temperature in

the late afternoon.• Maximum normal oral temperature

• At 6 AM : 37.2• At 4 PM : 37.7

• Anatomic variation• Physiologic variation:

• Age• Sex• Exercise• Circadian rhythm• Underlying disorders

Pathophysiology

• The normal body temperature is maintained by a complex regulatory system in the anterior hypothalamus.

• Development of fever begins with the release of endogenous pyrogens into the circulation as the result of infection, inflammatory processes (rheumatic disease), or malignancy.

Pathophysiology • Microbes and microbial toxins act as exogenous pyrogens by

stimulating release of endogenous pyrogens, which include cytokines such as interleukin-1, interleukin-6, tumor necrosis factor, and interferons that are released by monocytes, macrophages, mesangial cells, glial cells, epithelial cells, and B lymphocytes.

• Endogenous pyrogens reach the anterior hypothalamus via the arterial blood supply, liberating arachidonic acid, which is metabolized to prostaglandin E2, resulting in an elevation of the hypothalamic thermostat.

• Endotoxin stimulates endogenous pyrogen release and directly affects ther-moregulation in the hypothalamus.

PHYSIOLOGY OF FEVER

• Pyrogens:– Exogenous pyrogens:• Bacteria, Virus, Fungus, Allergen,…

–Endogenous pyrogen• Immune complex, lymphokine,…

• Major EPs: IL1, TNF, IL6

ACUTE PHASE RESPONSE

• Metabolic changes– Negative nitrogene balance– Loss of body weight

• Altered synthesis of hormones• Hematologic alterations– Leukocytosis– Thrombocytosis– Decreased erythrocytosis

• Altered hepatocyte function (Acute phase reactants)– C reactive protein(increased)– Serum amyloid A(increased)– Fibrinogen(increased)– Fibronectin(increased)– Haptoglobin(increased)– Ceruloplasmin(increased)– Ferritin(increased)– Albumin(decreased)– Transferrin(decreased)

DISCOMFORT DUE TO FEVER

• For each 1 °C elevation of body temperature:–Metabolic rate increase 10-15%–Insensible water loss increase

300-500ml/m2/day–O2 consumption increase 13%–Heart rate increase 10-15/min

ATTENUETED FEVER RESPONSE

• Fever may not be present despite infection in:–Newborn –Elderly–Uremia–Significant malnourished individual–Taking corticosteroids

Benefits of fever

• Benefits of fever– Protective role in the immune system

• Inhibition of growth and replication of microorganisms• Aids in body’s acute phase reaction• Enhanced immunologic function of wbc’s

– lymphocyte response to mitogens– bactericidal activity of neutrophils– production of interferon

• Promotion of monocyte maturation into macrophages• Promotion of lymphocyte activation and antibody production• Decreased availability of free iron for bacterial replication

HOW TO TAKE A CHILD’S TEMPERATURE

• A child's temperature can be taken:• from the rectum, ear, mouth, forehead, or

armpit. • It can be taken with a glass or digital

thermometer.

• Glass thermometers need to be shaken before use to make sure the temperature they show is below the normal body temperature (98.6° F, or about 37° C). Then they must be left in place for 2 to 3 minutes.

• Digital thermometers are easier to use and give much quicker readings (and usually give a signal when they are ready).

• Glass thermometers containing mercury are no longer recommended because they can break and expose people to mercury.

• Oral temperatures are taken by placing a glass or digital thermometer under the child's tongue. Oral temperatures provide reliable readings but are difficult to take in young children. Young children have difficulty keeping their mouth gently closed around the thermometer, which is necessary for an accurate reading. The age at which oral temperatures can be reliably taken varies from child to child but is typically after age 4.

• Rectal temperatures are most accurate. That is, they come closest to the child's true internal body temperature. For a rectal temperature, the bulb of the thermometer should be coated with a lubricant. Then the thermometer is gently inserted about 1/2 to 1 inch (about 1 1/4 to 2 1/2 centimeters) into the rectum while the child is lying face down. The child should be kept from moving.

• Ear temperatures are taken with a digital device that measures infrared radiation from the eardrum. Ear thermometers are unreliable in infants under 3 months old. For an ear temperature, the thermometer probe is placed around the opening of the ear so that a seal is formed, then the start button is pressed. A digital readout provides the temperature.

• Forehead (temporal artery) temperatures are taken with a digital device that measures infrared radiation from an artery in the forehead (the temporal artery). For a forehead temperature, the head of the thermometer is moved lightly across the forehead from hairline to hairline while pressing the scan button. A digital readout provides the temperature. Forehead temperatures are not as accurate as rectal temperatures, particularly in infants under 3 months old.

• Armpit temperatures are taken by placing a glass or digital thermometer in the child's armpit, directly on the skin. Doctors rarely use this method because it is less accurate than others (readings are usually too low and vary greatly). However, if caretakers are uncomfortable taking a rectal temperature and do not have a device to measure ear or forehead temperature, measuring armpit temperature may be better than not measuring temperature at all.

Thermometers ? Age Oral and rectal temperature measurements• Do not routinely use the oral and rectal routes to measure the

body temperature of children aged 0–5 years. • Measurement of body temperature at other sites• In infants under the age of 4 weeks, measure body

temperature with an electronic thermometer in the axilla. In children aged 4 weeks to 5 years, measure body

temperature by one of the following methods:• electronic thermometer in the axilla• chemical dot thermometer in the axilla• infra-red tympanic thermometer.

• Healthcare professionals who routinely use disposable chemical dot thermometers should consider using an alternative type of thermometer when multiple temperature measurements are required.

• Forehead chemical thermometers are unreliable and should not be used by healthcare professionals.

Grades of Fever

• A fever may be classified as mild (or 'low grade') if it's between 37.8°C and 38.5°C; or

• high (or 'high-grade') above 38.5°C.• very high: body temperatures in excess of

41°C,

• The pattern of fever in children may vary depending on the age of the child and the nature of the illness.

• Neonates may not have a febrile response and may be hypothermic despite significant infection,

• whereas older infants and children younger than 5 years old may have an exaggerated febrile response with temperatures of up to 105°F (40.6°C) in response to either a serious bacterial infection or an otherwise benign viral infection.

• Fever to this degree is unusual in older children and adolescents and suggests a serious process.

• The fever pattern does not distinguish fever caused by bacterial, viral, fungal, or parasitic organisms from that resulting from malignancy, autoimmune diseases, or drugs.

PATTERN OF FEVER

• Sustained (Continuous) Fever• Intermittent Fever (Hectic Fever)• Remittent Fever• Relapsing Fever:– Tertian Fever– Quartan Fever– Days of Fever Followed by a Several Days Afebrile– Pel Ebstein Fever– Fever Every 21 Day

PATTERN OF FEVER

• The pattern of fever may vary in different conditions and could assist in the diagnosis of the cause of the fever. Some of the types of fever are listed below:

Continuous fever: Fever that does not fluctuate more than 1°C in 24 hours is called continuous fever. It is seen in conditions like pneumonia, typhoid, urinary tract infections and infective endocarditis.

Remittent fever: Fever that fluctuates more than 1°C in 24 hours is referred to as remittent fever. Causes include typhoid and infectious mononucleosis.

Intermittent fever: Fever that is present only for some time in the day is called intermittent fever. Malaria caused by Plasmodium vivax results in fever every third day and that caused by Plasmodium malariae results in fever every fourth day.

PATTERN OF FEVER

• Hectic or septic fever: Fever variation between the highest and lowest temperatures is very large and more than 5°C. This type of fever is seen in septicemia.

Pel Ebstein fever: The febrile and afebrile periods alternate and follow a definite pattern. For example, in Hodgkin’s disease and other lymphomas, fever for 3 to 10 days is followed by a fever-free period of 3 to 10 days, with the same cycle repeating.

• Fever with rigors: Rigor is the shaking or excessive shivering that accompanies fever. Fever accompanied with rigors are seen in conditions like malaria, kala azar, filariasis, urinary tract infections, inflammation of gall bladder, septicemia, infective endocarditis or inflammation of the inner layer of the heart, abscesses and pneumonia.

• Personal History:– Age– Occupation– Place of origin,Travel

History– Habits: Consumption of

Unpasteurized Dairy Products.

• Underlying Diseases:– Splenectomy– Surgical Implantation of

Prosthesis– Immunodeficiency– Chronic Diseases:

• Cirrhosis• Chronic Heart Diseases• Chronic Lung Diseases

APPROACH TO FEVER

• Drug History:• Antipyretics• Immunosuppressants• Antibiotics

• Family History:• TB in the Family• Recent Infection in

the Family

• Associated Symptoms:• Shaking chills• Ear pain,Ear

drainage,Hearing loss• Visual and Eye Symptoms• Sore Throat• Chest and Pulmonary

Symptoms• Abdominal Symptoms• Back pain, Joint or

Skeletal pain

APPROACH TO FEVER

• Physical Examination:– Vital Signs– Neurological Exam.– Skin Lesions,Mucous Membrane– Eyes– ENT– Lymphadenopathy– Lungs and Heart– Abdominal Region (Hepatomegaly,Splenomegaly)– Musculoskeletal

APPROACH TO FEVER

• LABORATORY STUDY:• Assess the extent and severity of the

inflammatory response to infection• Determine the site(s) and complications of

organ involvement by the process• Determine the etiology of the infectious

disease.

APPROACH TO FEVER

Symptoms and signs of specific diseases

Meningococcal disease

Non-blanching rash, particularly with one or more of the following:

•an ill-looking child •lesions >2 mm in diameter (purpura) •a CRT of ≥3 seconds•neck stiffness

MeningitisNeck stiffness Bulging fontanelleDecreased level of consciousnessConvulsive status epilepticus

Herpes simplex encephalitis

Focal neurological signs Focal seizuresDecreased level of consciousness

PneumoniaTachypnoea Chest indrawingCrackles CyanosisNasal flaring Oxygen saturation ≤95%

Symptoms and signs of specific diseases (2)

Urinary tract infection (in children aged older than 3 months)

VomitingPoor feeding LethargyIrritabilityAbdominal pain or tenderness Urinary frequency or dysuriaOffensive urine or haematuria

Septic arthritis/ osteomyelitis

Swelling of a limb or jointNot using an extremityNon-weight bearing

Kawasaki disease

Fever >5 days and at least four of the following: •bilateral conjunctival injection •change in upper respiratory tract mucous membranes •change in the peripheral extremities•polymorphous rash •cervical lymphadenopathy

TREATMENT OF FEVER

• Most fevers are associated with self-limited infections, most commonly of viral origin.

• If the fever results from a disorder, that disorder is treated

• General measures: • Drinking plenty of clear fluids to replace fluids lost by sweating,

vomiting or diarrhoea – either water, or an oral rehydration solution which contains electrolytes.

• Changing clothing and bed linen frequently.• Tepid baths (but don't use cold water, as this can increase core

body temperature by cooling the skin and causing shivering).• Keeping clothes and blankets to a minimum.• Avoiding hot water bottles or electric blankets (which may raise

body temperature further).• Ventilating the room.• There are many other unhelpful folk remedies, ranging from the

harmless (for example, putting onions or potatoes in the child's socks) to the uncomfortable (for example, coining or cupping).

TREATMENT OF FEVER

• Drugs to lower fever:• Typically, the following drugs are used:• Acetaminophen, given by mouth or by

suppository• Ibuprofen, given by mouth• Rarely, acetaminophen or ibuprofen is given

to prevent a fever, as when infants have been vaccinated.

• Aspirin is no longer used for lowering fever in children because it can interact with certain viral infections (such as influenza or chickenpox) and cause a serious disorder called Reye syndrome

TREATMENT OF FEVER

Treatment Strategies

• Acetaminophen is generally a first-line antipyretic due to being well tolerated with minimal side effects.

• Pediatric dose: 10-15mg/kg q4-6h.• Ibuprofen:• 5-10 mg/kg/dose orally every 6 to 8 hours as

needed

“Fever is nature’s engine which she brings into the

field to remove her enemy”

Thomas SydenhamEnglish Physician

1624 - 1689

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thank you for your attention