Fever in children for medical student

2. 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.

3. 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 .

4. 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).

5. 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.

6. 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.

7. 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

8. 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.

9. 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.

10. PHYSIOLOGY OF FEVER
• Pyrogens:
–Exogenous pyrogens:
• Bacteria, Virus, Fungus, Allergen,…
–Endogenous pyrogen
• Immune complex, lymphokine,…
• Major EPs: IL1, TNF, IL6

11. 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)

12. 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

13. ATTENUETED FEVER RESPONSE
• Fever may not be present despite infection in:
–Newborn
–Elderly
–Uremia
–Significant malnourished individual
–Taking corticosteroids

14. 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

15. 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.

16. • 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.

17. • 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.

18. • 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.

19. • 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.

20. • 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.

21. 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.

22. • 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.

23. 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,

24. • 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

25. • 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

26. • 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

27. • 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.

28. • 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

29. • 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

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

31. • 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

32. 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
Meningitis
Neck stiffness
Bulging fontanelle
Decreased level of consciousness
Convulsive status epilepticus
Herpes simplex
encephalitis
Focal neurological signs
Focal seizures
Decreased level of consciousness
Pneumonia
Tachypnoea Chest indrawing
Crackles Cyanosis
Nasal flaring Oxygen saturation ≤95%

33. Symptoms and signs
of specific diseases (2)
Urinary tract
infection (in
children aged
older than 3
months)
Vomiting
Poor feeding
Lethargy
Irritability
Abdominal pain or tenderness
Urinary frequency or dysuria
Offensive urine or haematuria
Septic arthritis/
osteomyelitis
Swelling of a limb or joint
Not using an extremity
Non-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

34. 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

35. • 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

36. • 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

37. 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

38. “Fever is nature’s engine
which she brings into the
field to remove her
enemy”
Thomas Sydenham
English Physician
1624 - 1689

39. ••••••••••••••••••••••••••••••••
thank you for your attention