Fever

1. PREPARED BY :- MAHMUD
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2. CONTENTS
Introduction on fever
Definition
Type
Causes
Pathogenesis
Fever with localize sign
Fever without localize sign
Fever of unknown origin
Approach to a febrile child
Observation
History taking
Physical examination
Diagnosis
Laboratory investigation
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3. Introduction
Definition
What is fever?
-controlled increase in body temperature over the normal
value
-regulated by thermo sensitive neurons located in the
pre optic anterior and posterior hypothalamus
Thermoregulatory responses include
-redirecting of blood to or from cutaneous
vascular beds.
-increased or decreased sweating
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4. 4

5. 1.Based on period
-acute if 7-14 days
-chronic if > 14 days
2.Based on degree
.Low grade 37.2-38C
.Moderate 38-41C
.High grade >41C
Types of fever:
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6. . Intermittent fever- exaggerated circadian rhythm with
0.3-1.4C variation that also include a period of normal
temp for several hours in a day. Extremely wide
fluctuation with chills & sweating is called septic or
hectic fever >1.4.
. Remittent fever-is a fever that persists & varies by
more than 0.5C over 24 hours.
. Sustained fever-is a persistent f ever that does not
vary by more than 0.5C over 24 hours.
. Relapsing fever-is characterised by a febrile period
that are separated by interval of normal temp.
Tertian fever- occurs on the 1& 3 day.
Quartan fever-occurs on the 1 & 4 day.
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7. -indicate a single illness with two distinct periods of
fever
-over one or more weeks (camel back fever pattern)
e.g. poliomyelitis, rat bite fever.
Periodic fever- is used narrowly to describe fever
syndromes with a regular periodicity.
Undulant fever- fever that gradually increases for days
stays high then decrease gradually.
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8.  Hyperexia
-extraordinarily high fever (>41.5 0c)
- developed in patient with sever infection but most
commonly in patients with CNS hemorrhages.
 Hypothalamic fever
-elevated temperature caused by abnormal hypothalamic
function.
 Hyperthermia
-is uncontrolled increase in body temperature that exceeds
the body’s ability to loss heat
-doesn’t involve pyrogenic molecules.
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9.  cause of fever:
 1. infectiuous causes
-relapsing fever(borrelia recurrentis)
-malaria
-Typhus fever
-acute meningits
-typhoid fever (salmonella typhi)
-chronic meningococcemia
-acute rheumatic fever
-tuberculosis
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10.  Causes of hyperthermia
 1. CNS damage
 -cerebral hemorrhage,status
epilepticus,hypothalamic injury.
 2. Endocrinopathy
-thyrotoxicosis,pheochromocytoma
3. Drug induced hyperthermia
- amphetamine,cocaine,phencyclidine,MAOI,tricyclic
antidepressants
4. serotonin syndrome
- selective serotonin reuptake inhibitors (SSRI),
MAOI.

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11. 2.non infectious causes
 -crohns disease
 -weber christian disease(panniculitis)
 -leukoclastic angitis
-sweet syndrome
-systemic lupus erythromatosus
3. periodic fever syndromes
 -familial medtrranianean fever
 -cyclic neutropenea
 -hyper IgD syndrome
 - periodic fever ,aphthous stomatitis ,pharyngitis
,adenopathy(PFAPA)
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12.  Pathogenesis of fever
 Pyrogen: is a term used to descried any substance
that cause fever. These pyrogens can be :
1. exogenous pyrogens –are derived from out side
the patient (ie.microbial toxins or the whole micro
organisms)
2. indigenous pyrogens (ie. Pyrogenic cytokines )
 Pyrogenic cytokines include IL-1,IL-6,TNF,ciliary
neurotropic factor(CNTF). Each of these cytokines
are encoded by separate gene
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13.  Elevation of hypothalamic set point by
cytokines
During fever, the level of PGE2 is elevated. This elevation
of PGE2is both in the systemic circulation as well as in
the periphery.
- elevation of PGE2 in the systemic circulation results in
fever
- elevation of PGE2 in the periphery accounts for non
specific myalgias and arthralgias that often accompany
fever.
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14. .
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15. 15

16.  Fever of short duration accompanied by
localizing signs and symptoms, in which a
diagnosis can be established by clinical history
and physical examination
 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
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17.  Febrile convulsions are the most common seizure
disorders during childhood.
 They generally have excellent prognosis but may
also signify a serious underlying acute infectious
disease such as sepsis or bacterial meningitis.
 Febrile seizures are age dependent and are rare
before 9monthes and after 5years of age, peak
age of onset being 14-18monthes of age.
 Strong family history of febrile convulsion in
siblings and parents suggests a genetic
predisposition.
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18.  A febrile convulsion can be simple or
complex in type.
 A simple febrile convulsion is usually
associated with a core temperature that
increases rapidly to 39 degrees and above.
 It’s initially generalized tonic-clonic in
nature, lasts few seconds and rarely up to
15min, occurs only once in 24hr.
 A febrile seizure is described as complex or
complicated when the seizure lasts more
than 15min and repeated convulsions occur
within 24hr.
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19.  Approximately 30-50% children have recurrent
seizures with later episodes of fever.
 Factors with increased recurrence risk include:
age less than 12month, lower temperature
before seizure onset, positive family history of
febrile seizures, complex features
 Febrile seizures are not associated with
reduction in later intellectual performance
 Children with febrile seizures have only slightly
greater risk of later epilepsy than the general
population
 Risk factors include the above mentioned and
pre-existing neurologic disorder
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20.  Routine management of a normal infant with
simple brief febrile convulsions include a
careful search for the underlying cause of the
fever and educating the parents
 Antipyretics have not shown to prevent seizure
recurrrences but may reduce discomfort and
are reassuring.
 In settings where support for ventilation can be
provided, benzodiazepine should be given as
afirst line therapy.
 Prolonged aniconvulsant prophylaxis for
preventing recurrent febrile convulsions is controversial and
isno longer recommended for most children
 Antiepileptics such as phenytoin and carbamazepine do not
prevent febrile seizures.
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21.  Phenobarbital prevents recurrent seizures but
may also decrease cognitive function in treated
children compared with untreated ones.
 Sodium valproate is also effective for prevention
febrile seizures but the potential risks of the
drug do not justify its use in a disorder with an
excellent prognosis regardless of treatment.
 Another approach for selected patients with
recurrent complex febrile seizures is to prescribe
diazepam in the form of gel that can be given
rectally at the time of seizure.
 Preventive anticonvulsant therapy or treatment
after the seizure has not been shown to reduce
risk of later epilepsy in higher risk patients.
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22.  Fever with petechiae in an ill apearing
patient with or without localising sigins
indicates high risk for life threatening
bacterial infections such as bacteremia,
sepsis and meningitis.
 Management includes prompt hospitilization,
culture of blood and CSF, administration of
appropriate parenteral antimicrobial agents.
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23.  Several classic pediatric illnesses are
characterized primarily by fever and
generalized rash:
 Rubell infectiosum, and chicken pox,
Measles, roseola infantum, erythema .
 There are no specific treatments but routine
supportive care includes maintaining
adequate hydration and antipyretics.
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24.  Acutely ill febrile child with a serious illness identified
by:
careful observation
history taking
physical examination
Diagnosis
Laboratory investigation
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25.  There are 6 items of observation
 1. Quality of crying
 2. Reaction to parents stimulation
 3. State of variation
 4. Color
 5. Hydration
 6. Response to social overtures
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26.  During history taking, the following things should be
consider :
 1.Age:
 young children
 Older children
 Parents must transmit how a younger child has been
feeling.
 Can also provide information on specific symptoms.
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27.  The infants in the first 3 months of life is more
susceptible to
 sepsis,
meningitis.
 Generally children < 6yr of age have
-RTI,GUTI,Osteomyelitis.
- Adolescents patients
-expose to TB,IBD
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28.  2.Travel history –to endemic area.
e.g. from highland to lowland-malaria
from low land to high land-RF.
 A history of tick bite , travel to tick or parasite
infested areas should be obtained.
 3.Story of drug use(medication history)
-over-the-counter preparation(OTC )
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29.  4.Dietary history.
 -exposure to contaminated food and water-
TF.
 -uncooked food like meat.
 5.socio-economic status.
 6.pattern of fever;-continuous fever
-intermittent fever
-remittent fever
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30.  7.family history
 -information on family members.
- Genetically associated disease.
 8.Past history of similar illness: recurrent viral
infection are common in children especially in the
first year of school.
 9.Duration of fever: fever lasting for more than
4-7 days is rarely due to self limiting viral
infection. Greater than 2 weeks indicate serious
problem need detail investigation.
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31.  9.Progress of fever: fever due to viral
infection peaks over a day and decline
gradually in 3-4days.Bacterial fever worsen
if untreated.
 10.Immunization:vaccine preventable
disease are rare in immunized children.
 11.accompaning symptoms:
-specific symptoms held in
localizing the site of infection.
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32.  A good physical examination and a clinical history
are the basis for making a diagnosis.
 The laboratory tests are supportive.
 General apperance:well looking, ill looking,
distressed,weakness,awake,sleepy etc.
 Vital sign: Blood pressure, Pulse rate, Respiratory
rate and temperature.(oral, rectal)
o Caution: not shared with other patients.
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33. part of
body
physical finding CAUSE
Eye Pale conjuctivae,watery
discharge,
purulent,tenderness,swelling.
Anemia, viral or
bacterial infection
Lung Coughing, tachypnea, crackles,
rhonchi, decreased breath sounds,
wheezing
Lower respiratory
infection
.(eg,pneumonia,
bronchitis,
pulmonary foreign
body)
Neck Adenopathy, with or without
redness and tenderness,
Pain or resistance to flexion
Upper respiratory
infection
Lymphadenitis
Meningitis
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34. Abdomen Ab
distention,mass,ten
derness,abs of
abdomenal sound
Gastroenteritis,
Peritonitis,
Tumor,
Appendicitis.
Pyelonephritis
Extremities Joint swelling,
erythema,
tenderness
Septic arthritis (very
tender)
Rheumatoid or
inflammatory
disorder
Osteomyelitis
Fontanelle
(infants)
Bulging Meningitis or
encephalitis
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35. Nose Congestion, discharge
Nasal flaring with
inspiration
URI
Sinusitis
LRI
pharynx Redness
Sometimes exudate or
swelling
Pharyngitis (URI or strep
infection)
Retropharyngeal abscess
Tonsillitis
Tympanic
membranes
Red, bulging membrane,
loss of landmarks
Otitis media
Back Tenderness of
spine&CVA
Osteomylitis,pyelonephri
tis
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36. Skin
Petechiae
Rash
Focal erythema with
swelling
Nodule, discharge
sepsis
Erythema
infetiosum
(parvovirus B19)
arthritis
Lyme disease
Scarlet fever
Meningeal
sign
Neck
stiffness,Kerning&Brud
zinski sign test
Meangitis
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37. 4. DIAGNOSIS
 How is fever diagnosed?
 Diagnosing a fever is straightforward - the patient's
temperature is taken, if the reading is high, he/she
has a fever. It is important to take the person's
temperature when they are at rest, because
physical activity can warm us up.
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38. A person is said to have a fever if:
 The temperature in the mouth is over 37.7.
 The temperature in the rectum (anus) is over 37.5-
38.3.
 The temperature under the arm or ear is over
37.2.
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39.  As a fever is a sign rather than a disease,
when the doctor has confirmed there is an
elevated body temperature, certain
diagnostic tests may be ordered, depending
on what other signs and symptoms exist.
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40. 5. Laboratory investigation:
 Testing depends on whether fever is acute or
chronic.
 For acute fever, testing for infectious causes is
directed by the age of the child .
 All febrile children < 3 mo require a WBC count
with a manual differential, blood cultures, and
urinalysis and urine culture.
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41.  Lumbar puncture is mandatory for children <
28 day. Chest x-ray, stool swabs for WBCs,
stool cultures, and acute-phase reactant
tests (eg, ESR, C-reactive protein) are done
depending on symptoms and degree of
suspicion.
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42.  Children without focal findings should have
initial screening tests, including
 Complete Blood Count
 Urinalysis and culture
 ESR (C-reactive protein is also considered,
although one is not necessarily better than
the other)
 PPD for TB screening(TST).
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43. THANKS
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