4. INTRODUCTION
• NORMAL BODY TEMPERATURE -36.6
to 37.2 °C
• Regulated by thermosensitive neurons in
the
Preoptic and anterior hypothalamus
• Thermoregulatory responses:
Redirecting blood to or from cutaneous
vascular beds
Increased or decreased sweating
ECF regulation
Behavioral responses
• Circadian rhythm or diurnal variation
5. • Skin temperature is 0.4 °C(0.7° F)
lower than oral temperature
• Rectal or eardrum temperature is 0.4
°C (0.7° F) higher than oral temperature
• Oral temperature is the reference and
fever is diagnosed when it exceeds
(37.8° C).
6. DEFINITION OF FEVER
• Fever is a controlled increase in body
temperature above the normal
hypothalamic set point
• Rectal temperature >38 °C
• Hyperpyrexia is > 40° C
35. Pel-Ebstien fever- lasting for 3-10 days followed by an
afebrile period of 3-10 days,e.g.hodgkins and other lymphomas.
Saddle back fever- fever lasts for 2-3 days
followed by a remission for 2-3 days and
reappearance after 2-3 days,e.g.Dengue fever.
Biphasic fever- single illness two distinct
periods of fever over one or more weeks(camel back
pattern),e.g. poliomyeletis,leptospirosis,dengue fever,
yellow fever,colarado tick fever,spirillary bat
fever,african haemorrhagic fever.
39. FEVER WITHOUT A FOCUS
• Fever without a focus refers to a
rectal temperature of 38 degree
centigrade or higher as the sole
presenting feature.
• It has two subcategories :-
-fever without localizing signs
-fever of unknown origin.
40. Fever of unknown origin
Best reserved for children with a fever ;
lasted for 3 or more weeks
with temperature >38 C
for which cause could not be identified after 3 wks of
evaluation as an outpatient or after 1wk of evaluation in
hospital .
Fever without localizing signs
Patients with fever not meeting above criteria , and specifically
those admitted to hospital with neither an apparent site of
infection nor a noninfectious diagnosis .
41. Fever without localizing signs
• Fever of acute onset , with duration of <1 wk and without
localizing signs is a common diagnostic dilemma in
children < 36 months of age .
• Etiology and evaluation of this type depends upon age
of the child , 3 age groups are considered :
I. Neonates or infants to 1 month of age .
II. Infants > 1 month to 3 months of age .
III. children > 3 months to 3 yrs of age .
42. Febrile patients at increased risk for serious
bacterial infections
RISK GROUP DIAGNOSTIC
CONSIDERATIONS
Immunocompetent
patients
Neonates(<28 days) Sepsis and meningitis- group B
streptococcus, E. coli, listeria, HSV,
enteroviruses
Infants 1-3 months Serious bacterial disease 10-15%
,bacteremia 5% UTI
Infants & children 3-36 months Occult bacteremia 0.5% of children
immunized with Hib pneumococcal
conjugate vaccine ,UTI
43. IMMUNOCOMPROMISED
PATIENTS
Sickle cell disease Sepsis, pneumonia, meningitis caused by
S. pneumoniae, osteomyelitis caused by
Salmonella and Staphylococcus aureus
Agammaglobulinemia Bacteremia ,sinopulmonary infections
AIDS S.pneumoniae, H.influenza ,Salmonella
Congenital heart disease Infective endocarditis ,Brain abscess with
right to left shunting
Malignancy Bacteremia with gram –ve enteric bacteria
, S.aureus & coagulase –ve staphylococci ,
fungemia with candida & aspergillus
44. Fever without localizing signs in
NEONATES
• Neonates having fever without focus display limited
signs of infection making difficult to clinically
distinguish between a serious bacterial infection & self
limited viral illness .
• SERIOUS BACTERIAL INFECTION-7% neonates ,
includes sepsis,meningitis,UTI,enteritis,osteomyelitis
,suppurative osteoarthritis .
• Organisms responsible - group B streptococcus &
Listeria(Late onset neonatal sepsis & meningitis) ,
community acquired pathogens (Salmonella, E.coli,
Haemophillus influenza type B, Streptococcus
pneumoniae, staphylococcus aureus )
45. • Viral causes
o Viral pathogens can be identified in 40-
60%
febrile infants .
o Perinatally acquired HSV infection
o Respiratory syncytial virus, Influenza A
virus (common during winter)
o Enterovirus infection (common during
summer)
46. Guidelines for investigations
• If fever is recorded at home by reliable
parent , then treat as febrile neonate .
• In false cases excess covering should be
removed & temp. retaken in 15-30min .
• Blood ,urine ,CSF should be cultured .
• CSF study includes cell counts, glucose,
protein levels, gram stain & culture.
• HSV & Enteroviruse polymerase chain
reaction .
• Stool culture ,chest radiograph .
47. Treatment
For ill appearing febrile infants ceftriaxone
(50mg/kg every 24 hours – normal CSF finding,
80mg/kg every 24 hours – CSF pleocytosis) or
cefotaxime(50 mg/kg every 6 hr) ,plus
Ampicillin(50mg/kg every 6 hr) to cover
L.monocytogenes & Enterococcus .
Meningitis – vancomycin (15 mg/kg every 6 hr) for
penicillin resistant S. pneumoniae .
Acyclovir for HSV infection .
For infants with fever who appear generally well
& have a total WBC count of 5000-15000 cells/ml
& normal urinalysis results are unlikely to have
serious bacterial infection .
48. 1 Month to 3 Months:
• Majority of the cases are of viral origin
• Viral diseases have a distinct seasonal pattern
Eg - 1.Respiratory syncytial virus and
influenza A in winter season
2.Entero virus in summer
• Although viral infection are common one should
suspect serious bacterial infections.
• Common bacteria :
Group B streptococci
Salmonella enteritis
Streptococcus pneumoniae
H influenza etc…
49. • Common conditions:
> Pyelonephritis
>Otitis media
>Pneumonia
>Skin and soft tissue infections
• These infants require prompt
hospitalization and immediate
antimicrobial therapy
• Based on culture of blood ,urine ,CSF the
infants are classified in to low and high
risk group
50. Low risk criteria in 1-3months old with
fever
BOSTON ROCHESTER
CRITERIA: CRITERIA:
CBC: <20,000 CBC : 5000-
Infants are at low WBC /mm3 15000
risk if they appear WBC/mm3
well , have normal
physical
examination and
laboratory test as Urine : -ve Urine :<10
follows leucocyte WBC/HPF at
esterase 40x
CSF: leucocyte Stool :<5 WBC
count /HPF if diarrhea
<10x106/litre
51. PHILADELPHIA PITTSBURGH
PROTOCOL: GUIDELINES:
CBC :<15000 CBC:5000-15000
WBC/mm3 WBC/mm3
Urine :<10 WBC/HPF,
Urine :9 WBC/mm3,no
no bacteria on Gram
bacteria on gram stain
stain
CSF:5WBC/mm3,-ve gram
CSF:<8 WBC /mm3,no stain ,if bloody tap then
bacteria on Gram stain WBC :RBC </= 1:500
Chest radiograph :no
infiltrate Chest radiograph: no
infiltrate
Stool : no RBC,few to
no WBC Stool :5 WBC/HPF with
diarrhea
52. Management :
Low risk : High risk:
• with out antibiotic under • Intensive parenteral
close observation antimicrobial therapy
• Empirical antibiotic therapy • Ampicillin plus either
ceftriaxone / cefotaxime
• If CSF shows abnormal
findings vancomycin
included against penicillin
resistant S.Pneumoniae
53. 3 Month to 36 Months of Age
• 30% of these infants with fever have no
localizing signs of infection
• Majority are viral
• But serious bacterial infection do occur
• Pathogens are same as 1 to 3 months of age
• S.pneumoniae, N.meningitidis and
Solmonella acount for the most of occult
bacteremia.
• Hib was important cause in young children in
the pre immunization era.
54. • Risk actors indicating occult bacteremia
1.temperature >39° c
2.WBC count >15000/micro litre
3.elevated
a.ANC
b.CRP
c.ESR
• Occult bacteremia caused by S. pneumoniae,
Hib is the common condition
• It may resolve spontaneously without sequelae
or can lead to localized infection like meningitis,
pneumonia, cellulitis ,pericarditis etc..
55. MANAGEMENT:
Immunization against
Hib and S.pneumoniae
with conjugate vaccine.
Hospitalization and
prompt antimicrobial
therapy
Based on the blood,
urine ,CSF culture
antibiotics are given.
56. Fever of Unknown Origin
• Definition :
It is a term best reserved for children with a
fever documented by a health care provider &
fever :
has lasted for 3 or more weeks .
with temperature > 38 degree C on most days .
& for which cause could not be identified after
3 weeks of evaluation as an outpatient or after
1 week of evaluation in hospital .
57. Classification :
• Fever of unknown origin is classified
into following 4 categories :
1. Classic FUO
2. Health care associated FUO
3. Immune defficient FUO
4. HIV –related FUO
58. 1. CLASSIC FUO
Definition: fever of > 38 degree C , lasted for > 3 wks , &
cause could not be identified after 3 wks of evaluation as
outpatient or after 1 wk in hospital .
Patient location : community , clinic , or hospital .
Leading causes : cancer , infections , inflammatory conditions ,
undiagnosed , habitual hyperthermia .
History emphasis : H/O travel , contacts , animal & insect
exposure , medications , immunization , family history , cardiac
valve disorder .
Examination emphasis : Fundi ,oropharynx , temporal artery ,
abdomen , lymph nodes , spleen , joints , skin , nails ,
genitalia , lower limb deep veins .
59. ,
Investigation emphasis : Imaging , biopsies ,
erythrocyte sedimentation rate , skin test .
Management : Observation , outpatient
temperature chart , investigations , avoidance of
empirical drug treatment .
Time course of disease : For months .
60. 2. HEALTH CARE ASSOCIATED FUO
Definition :Fever of > 38 degree C , lasted for > 1 week ,
not present or incubating on admission .
Patient location : Acute care hospital .
Leading causes : Hospital acquired infections , post-
operative complication , drug fever .
History emphasis : Operation & procedures , devices used ,
anatomic considerations , drug treatment .
Examination emphasis : Wounds , drains , devices , sinuses
, urine .
61. Investigation emphasis : Imaging , bacterial cultures
& other microbiological investigations .
Management : Depends upon situation .
Time course of disease : Lasts for weeks .
62. 3. IMMUNE DEFICIENT FUO
Definition : Fever of > 38 degree C , lasted for > 1 wk , &
negative culture after 48 hrs .
Patient location : Hospital or clinic .
Leading causes : Majority are due to infections but
cause has been documented in only 40-60% .
History emphasis : Stage of chemotherapy , drugs
administered , underlying immunosuppressive disorder .
63. Examination emphasis : Skin folds , IV sites , lungs.
Investgation emphasis : Chest radiograph , bacterial
cultures ,
Management : Antimicrobial treatment .
Time course of disease : Lasts for days .
64. 4. HIV – RELATED FUO
Definition :Fever of >38 degree C , >3 wks for outpatients ,
>1 wk for inpatients & HIV infection confirmed .
Patient location : Community , clinic or hospital .
Leading causes : HIV (primary infection) , typical & atypical
mycobacteria , CMV , toxoplasmosis , cryptococcosis ,
lymphomas , immune reconstitution inflammatory syndrome
(IRIS) .
Examination emphasis : Mouth , sinuses , skin , lymph nodes
, eyes .
65. Investigation emphasis : Blood & lymphocyte count ,
serologic tests , chest X-ray , stool examination, biopsies
of lung , bone marrow & liver for cultures and cytologic
tests , brain imaging .
Management : Antiviral & antimicrobial protocols ,
vaccines , revision of treatment regimen , good nutrition .
Time course of disease : Lasts for weeks to months .
83. APPROACH TO PUO
HISTORY
PHYSICAL
EXAMINATION
LABORATORY
INESTIGATIONS
84. GENERAL INFO
• History should be taken from the child or
reliable informant.
• Significance of age-
1-5 yrs - common causes are RTI,UTI
diarrhoea and osteomyelitis .
5-10 yrs-measles, mumps,chicken
pox,Typhoid
>10yrs- TB, Typhoid , Rheumatic
fever
85. GENDER.
• Females-urinary tract infections ,pelvic
infections , .
• Males-allergic fever(hay fever), typhoid ,,
tuberculosis.
malaria.
ADDRESS
• ENDEMIC- e.g,mandya for malaria and
japanese encephalitis.
• Epidemics , out breaks in that area
86. CHIEF COMPLAINTS
• History of Fever and other symptoms Should
be taken in chronological order.
• They give clue towards system involved
eg:-
fever , cough, rhinitis , sore throat -RTI
fever, vomiting ,diarrhoea ,pain abdomen -
GIT
infection
fever ,dysuria ,loin pain -UTI
fever ,drowsiness ,convulsions -
meningitis, encephalitis
88. Duration
short long
1.malaria 1.Brucellosis
2.Dengue 2.malignancies
3.measles 3. Rheumatic fever
4.varicella
.
89. PROGRESSION
• Viral fever-peaks in 2 days and
declines.
• Bacterial fever-worsens day by day
without treatment.
• Parasite fever like malaria-shows cyclic
cold,hot and sweating stages.
93. HISTORY OF
• travel?-endemic areas?,how long?any
precaution?. Epidemics in resident area ?
• Pets,pica-toxoplasmosis,visceral larva migrans.
• Contact with animals? –leptospirosis,brucellosis.
• Tick bites-relapsing fever, Q fever.
• Blood transfusion-malaria,hepatitis-B virus.
• Migrating joint pains-Rheumatic fever
• Loss of weight-malignancies!
• History of recurrent fever , oral
thrush(immunocompromised)
• Joint pain,rash,photosensitivity(autoimmune)
94. •Past history-
•Surgeries(occult infection)
• Family history-
similar complaints suggest
infectious disease.
genetic background-familial
dysautonomia(recurrent hyperpyrexia)
• Personal history –
diet –unpasteurized milk(brucellosis,TB)
95. • Raw egg -salmonella species infection
• loss of appetite- malignancies
,TB, appendicitis.
96. • Breast feeding- Children who are not
breast fed are susceptible for infection
• Immunization history – vaccination
induced fever.e.g,DPT,measles
• Treatment history-penicillin ,
antihistamines.(drug induced fever)
97. PHYSICAL EXAMINATION
A careful and complete physical
examination is essential to find clue
to the underlying diagnosis
Repetitive examination ,preferable
daily examination is important to
pick up subtle or new signs
98. Look for the child’s general appearance , whether,
sick and toxic or looks well in spite of fever.
including sweating during fever
Continues absence of sweat , in the presence of
elevated or changing temperature because
suggest
Dehydration due to vomiting, diarrhea, central or
nephrogenic diabetic insipidus.
It also suggests exposure of child to atropine
99. Look for temperature pattern during hospitalization
Pulse rate –relative bradycardia –typhoid, meningitis
dengue,weil’s disease.
Skin – look for – rashes , petechiae, splinter
hemorrhages, subctaneous nodules – vasculitis ,
endocarditis.
Built and nourishment –by anthropometric
measurment .
100. Head to toe examination
Ophthalmic examination
Anemia- malaria, kala azar , ALL , SABE
Icterus – infectious hepatitis, malaria, weil’s disease ,
liver abscess, infectious mononucleosis
Proptosis –orbital tumor , thyrotoxicosis, orbital infection
, wegener granulomatosis , metastasis(neuroblastoma)
Petechial conjunctival hemorrhage , roth’s spots –
infective endocarditis
Uveitis –sarcoidosis, SLE, kawasaki disease , vasculitis
103. • In hypothalamic dysfunction – failure of
pupillary constriction –due to absence of
sphinctr constrictor muscle
• Choroid tubercles in fundus – tuberculosis
104. • Tenderness to tapping over sinus – sinusitis
• Oral cavity
• Hyperemia of pharynx – with or with out
exudate – infectious mononucleosis , CMV
infection ,
• Tender tooth – periapical abscess
• Ulceration – disseminated histoplasmosis
• Recurrent oral candidiasis – disorder of
immune system
• Smooth tongue with absence of fungiform
papillae – familial dysautonomia
105. • Fever blister – seen in - pneumococcal ,
streptococcal ,malaria, rickettsial infection
• Neck
• Enlargment or tenderness of thyroid gland –
thyroiditis
• Heart- Murmur – infective endocarditis
• Abdomen –splenomegaly – infective endocarditis,
malaria, kala azar , CML,
• abdominal tenderness-pelvic abccess.
• Loin tenderness-pyelonephritis.
• Hepatomegaly- liver abscess , primary or
metastatic malignancy
106. • Muscle and bone should be palpated
• Point tenderness- occult osteomyelitis or bone marrow
invasion from neoplasm
• Painful and swollen joints – arthritis – rheumatic fever ,
SABE , leukemia,
• Tenderness over trapezius muscle –clue to -
subdiaphragmatic abscess
• Generalised muscle tenderness – arboviral infection,
dermatomyositis , trichinosis ,
109. CASE BY CASE BASIS
CASE
1
LABORATORY
INVESTIGATIONS
CASE CASE
2 3
110. HOW TO GO ABOUT LABORATORY
INVESTIGATIONS
DETAILED
HISTORY
LABORATORY PRESENTATION
INVESTIGATIONS OF ILLNESS
CLINICAL
EXAMINATION
111. HOW TO GO ABOUT LABORATORY
INVESTIGATIONS
HISTORY
SUDDEN IN CHRONIC
ONSET PRESENTATION
OUT PATIENT
BASIS
HOSPITALIZATION INVESTIGATIONS
REGULAR CHECK
UP
112. WHAT IF HISTORY & PHYSICAL
EXAMINATIONS ARE NOT SIGNIFICANT…!!!
NO CLUES
CONTINUED SURVEILLANCE
RE-EVALUATION
NEW CLINICAL FINDINGS
113. LIST OF INVESTIGATIONS WHICH HELP
US ARRIVE AT THE DIAGNOSIS
• Blood cell count
• Urine analysis
• Blood smear
• Erythrocyte sedimentation rate
• Blood and urine culture
• Radiological diagnosis
• Bone marrow examination
• Serologic tests
• Radionuclide scans
• CT and MRI
114. BLOOD CELL COUNT
Differential WBC count is a must….
ABSOLUTE <5000/MICRO LITER INDOLENT BACTERIAL
NEUTROPHIL COUNT INFECTION
PMN
>10000/MICRO
LITER
SEVERE BACTERIAL
INFECTIONS
NON >500/MICROLITRE
SEGMENTED
PMN
116. ERYTHROCYTE SEDIMENTATION RATE
FURTHER
>30mm/hr INFLAMATION
EVALUATION
ESR TUBERCULOSIS
>100mm/hr MALIGNANCY
AUTO IMMUNE
117. BLOOD CULTURES
Normally aerobic culture is done as anaerobic
culture gives low yield.
Repeated culture done in case of infective
endocarditis and osteomyelitis.
Poly microbial infection suggests GI infection.
118. RADIOLOGICAL EXAMINATIONS
RADIOLOGICAL
EXAMINATION
PHYSICAL
HISTORY
FINDINGS
SINUSES &
CHEST GI TRACT
MASTOID
119. BONE MARROW EXAMINATION
BONE MARROW
EXAMINATION
BIOPSY ASPIRATION
METASTATIC LEUKEMIA
NEOPLASM CULTURE
FUNGI
FUNGAL
&PARASITIC
INFECTIONS BACTERIAL
120. SEROLOGIC TESTS
• SPECIFICITY & SENSITIVITY are the two
important aspects which should be checked
before ordering serologic examinations.
INFECTIVE
CMV MONONUCLEOSIS
SEROLOGY
BRUCELLOSIS TOXOPLASMOSIS
121. RADIONUCLEIDE SCANS
• These are mainly helpful in detecting abdominal
abscess & osteomyelitis, especially in multifocal
disease.
• GALLIUM CITRATE- mainly localizes in
inflammatory tissues.
• IODINATED IgG- helpful in detecting localized
pyogenic abscess.
123. CT SCAN AND MRI
• These permit detection of neoplasms with out
the use of surgical exploration.
• CT scan guided aspiration & biopsy has
reduced the need for surgical exploration.
• MRI is mainly useful in detecting
osteomyelitis .
124.
125. SUMMARY
ETIOLOGY SHOULD BE KEPT IN MIND
COMPLETE HISTORY IS TAKEN
COMPLETE PHYSICAL EXAMINATION DONE
REQUIRED INVESTIGATIONS DONE
WE ARRIVE AT THE DIAGNOSIS
126. REFERENCES.
Nelson text book of paediatrics 19th
edition( pg-839-846)
IAP text book of paediatrics(pg-295-302)
O.P Ghai textbook of paediatrics(pg)
Meharban singh textbook of paediatrics