Fever in Children
Axillary 1°C lower than core; tympanics unreliable; Height of fever irrelevant; may be hypothermic;
concern if >38°C; those <3/12 with viral illness have significant incidence of UTI, so still need to do urine
Appears ill
13-21% SBI
Appears well
<5% SBI
Appears ill
13-21% SBI
Appears well
<5% SBI
Neonates have 2x risk of SBI than 4-8/52
<1/12
<3/12
3-6/12
Pyrexia
<1% SBI
UTI in 3-8%
T <38.9°C
1% bacteraemia
UTI most common cause of fever without
focus
T >39°C
3% bacteraemia
T > 40°C
10% bacteraemia
WCC >15 + fever
10% bacteraemia
3-36/12 + febrile
+ appears well
0.5-0.7% sepsis
6/12 –
2yrs
Any fever
10% SBI
T >40°C
10% SBI
SIRS
Definitions
Aetiology
UTI most common cause
T >38°C / <36°C + HR >160 (infants) / >150 (children)
+ RR >60 (infants) / >50 (children)
+ WCC >12 / >10% band forms
Severe sepsis
As above + hypotension (<65 infants, <75 children, <90 adolescent)
Simple febrile convulsion
6/12 - 5yrs; T >38.5°C; generalised seizure; short post-ictal period;
1 seizure / fever; duration <15 minutes; no focal neurological deficit
afterwards
Neonate
Gp B Strep (30%) > E coli (30-40%) > N meningitidis > Hib > Strep pneumoniae > Listeria
Vertical transmission more likely; higher mortality; pneumonia common; other G-ive 1520% (eg. Klebsiella), G +ive 10%; enterococci, C trachomatis, herpes simplex; enterovirus,
RSV, influenza A
<3/12
N meningitidis > Hib > Strep pneumoniae > Gp B Strep > E coli > Listeria
In pneumonia: Chlamydia trachomatis (develops in 3-16% exposed, conjunctivitis in 50%) >
RSV > other viruses > Bordatella pertussis
<1yr
In pneumonia: RSV > other viruses > strep pneumoniae > Hib > C trachomatis >
mycoplasma pneumoniae
<5yrs
N meningitidis > Strep pneumoniae > Hib
In pneumonia: viruses > S pneumonaie > Hib > M pneumoniae > C pneumoniae (also S
aureus, B pertussis)
>5yrs
N meningitidis > Strep pneumoniae
In pneumonia: M pneumoniae > S pneumonaie > C pneumoniae > Hib/a > adenovirus >
other viruses (also S aureus, Legionella)
Aetiology
(cntd)
Immunocompromised, neurosurgery, trauma: Staph, gram negativess, cryptococcus neoformans
Developing countries: mycoplasma TB
Brain abscess: strep viridans, anaerobes, G negatives, staph aureus
Viral: enterovirus, HSV, VZV, CMV, EBV
Chronic lung disease (pneumonia): Cystic fibrosis: S aureus, pseudomonas
Sickle cell anaemia: encapsulated
Immunocompromised: pneumocystis, aspergillis, histoplasma
(nodular on CXR), CMV, fungi
Febrile
Convulsions
Epidemiology: in 3-5% children; 30-40% recurrent especially if <1yr; ; 3% go on to suffer epilepsy; have
no effect on CSF WCC
LP in first febrile convulsion: if you think it’s meningitis, treat and do LP when improve
Pros: mental state difficult to assess post-ictally; fulminant infections require early diagnosis; quick
Cons: <5% have meningitis; traumatic to child / family; may cause meningeal seeding if bacteraemia;
coning
Management: seek cause of fever; seek concurrent antibiotics; investigate as per usual fever; consider
need for cancer / glucose / pyridoxine
Remember: weight = (age + 4) x 2
or
>10yrs = age x 3
1. Diazepam 0.25mg/kg IV / 0.5mg/kg PR
or
Midazolam 0.15mg/kg IV / IM / buccal
2. Repeat after 5mins
3. Phenytoin 18mg/kg over 30mins (will be slow at controlling seizures)
Or Phenobarbitone 18mg/kg over 30mins
4. Thiopental 5mg/kg IV + RSI
If no IV access: paraldehyde 0.3mg/kg PR (good if mentally handicapped / recurrent seizures)
Prognosis:  risk of febrile convulsion recurrence if: repetitive seizures, focal features, onset <1yr, brief
duration between fever onset and seizure; FH
Differential diagnosis: Infantile spasm: sudden brief flexion of arms, head and trunk, occurring in clusters
Breath-holding spells: noxious stimulus; after brief cry / vigorous crying
Benign neonatal sleep myoclonus / Benign focal epilepsy of childhood /
Nocturnal frontal lobe seizures / Night terrors
Urinary Tract
Infections
Epidemiology: incidence 5% in children aged 3-24/12 with fever; affects 1% boys, 3% girls before
puberty; females:males 3:1 (except in neonates); circumcised:uncircumcised 10:1; most common SBI;
present in 3-8% young children presenting with fever and no obvious source; 5-10% with symptomatic
UTI will develop renal scarring ( HTN, CRF, eclampsia) and bacteraemia; systemic sepsis in 30% 13/12, 5% >3/12; 2% children have asymptomatic bacteruria which is not cause for presentation;
pyelonephritis suggested if T >39°C and +ive urine; 10% young infants with UTI have sterile WCC in CSF
Pathophysiology: haematogenous seeding in neonates; ascending otherwise; cystitis can cause
vesicoureteric reflux
Bacteria: 84% E coli, 6% proteus, 5% klebsiella, 3.5% enterococcus; G+ives in older boys and children with
underlying medical conditions
Investigation: Urine: always send for culture if suspect UTI; always send for microscopy regardless of
result of dipstick (unless low risk and negative dipstick); do repeat urine at 10/7 to
ensure clearance
Nitrites:
40% sensitivity (doesn’t develop with G+ives)
95-99% specificity
WBC dipstick: 70-80% sensitivity
80-90% specificity
Gram stain 80-97% sensitivity; sensitivity  if <2yrs
WBC:
50-90% sensitivity
50-90% specificity
Bacteria:
50-90% sensitivity
10-90% specificity
Microscopy – 15% false negative rate; significant number missed; may get moderate leucocytess in 40%
febrile children without UTI
MSSU: good sensitivity, positive if WCC >5-10
Bag spec: unreliable; if negative still needs to be sent for culture; can be used if pre-test
probability low
Catheter spec: positive if WCC >1-5
SPA: positive if WCC >0; must have at least 15ml on USS, go 1cm superior to pubic symphysis with
23G needle; 50% success rate blind, 95% with USS guidance)
Blood: do blood culture if positive urine and <1yr, or ill enough to require admission
LP: consider if <1/12
Renal USS: do in all children with 1st UTI, 3-6/52 after infection; also do if sibling of child with VUR;
abnormalities found in 40%; obstructive lesions found more commonly in young (<3/12)
Urinary Tract
Infections
(cntd)
Meningitis
DMSA scan: do after 6/12 or at age 3-4yrs to look for scarring if required hospitalisation
MCU: do if <3/12 or if abnormal USS
Admit if: <6/12, septic, significant underlying disease, urinary obstruction, pyelonephritis, failure to
respond to PO’s
Prophylaxis: give if recurrent UTI’s, <3/12 awaiting MCU, known VUR or other renal abnormality;
continue until after USS; give 2mg/kg co-trimoxazole or 3mg/kg nitrofurantoin nocte or 5-10mg/kg
cefaclor nocte
Epidemiology: 90% occur <5yrs; 5% mortality; 10-20% intellectual / auditory complications;
asymptomatic N meningitidis nasal carriage in 10%; meningococcal sepsis bimodal (0-4yrs, 15-25yrs);
<3/12 + febrile = 1% incidence
Pathophysiology: usually haematogenous spread from URTI; can also be direct (eg. Otitis media), injury
Risk factors: young, male, low SEG, congenital abnormalities, shunt, trauma, immunocompromised
Assessment: may be afebrile / hypothermic; bulging fontanelle is late finding and masked by
dehydration; signs of meningeal irritation may be absent <18/12; focal neurological deficit in 15% (30%
pneumococcus); seizures in 30% (with worse than expected mental status after); 15-20%  LOC (more
in pneumococcus); subdural effusion / empyema (30% in Hib, 20% in strep); may deteriorate after
antibiotics (bacteriolysis  inflammation); beware partially treated meningitis (more frequent
vomiting, longer duration of symptoms); suspect encephalitis if seizures / altered LOC / behaviour; early
purpura may just be erytematous macules
LP: consider pre-oxygenation before LP; use non-styleted needle in small infants; neck in mid-flexion
CSF interpretation: CSF protein  0.01g for every 1000 RBC; lymphocytes >50% in 10% bacterial
meningitis; Gram stain 80% sensitivity (50% if pre-treated); may mistake G+ive for G-ive if pre-treated;
nearly 100% mononuclear when viral (may be more PMN’s if <48hrs; monocytes are most common
WBC in viral); visible budding MO’s on Indian ink staining = cryptococcal; CSF antigen tests have high
sensitivity and specificity (especially for Hib and N meningititis)
CT before LP if: FND,  LOC
Contraindications to LP: signs of  ICP, coma, FND, focal seizures, seizures >30 minutes,
haemodynamically unstable, significant respiratory compromise, purpura, coagulopathy,  platelets,
localised skin infection
Other Investigations: bloods; meningococcal PCR; antigen studies on blood and urine; throat swab for N
meningitidis
Management: if shocked, 10-20ml/kg N saline; SIADH in 30% so use 50% maintenance after resus; treat
seizure, fever, hypoglycaemia, hyponatraemia (fluid restriction if Na <135),  intracranial pressure
Antibiotics: give antibiotics before LP if there will be >20min delay to LP
Dexamethasone: 0.25mg/kg (max 10mg) IV/IM Q6h for 48hrs; use if >1/12 to  host response to
bacteria and  deafness; give at least 15-30mins before (or within 1hr of antibiotics); best in Hib
Contact prophylaxis: meningococcus / Hib – give rifampicin 10mg/kg BD x4 (contraindicateded in
pregnancy and liver disease; ceftriaxone IM or ciprofloxacin PO if contraindicated); contact = family and
household contacts, those exposed to oral secretions, sexual partners, health care workers, staff and
children at pre-school in last 10/7
Normal
neonate
Normal
child
Bacterial
Partially
treated
Viral
Encephalitis
TB
Opening pressure
5
8.5
WCC
<30
<5-10
200-5000
200-5000
100-700
<500
100-500
% PMN’s
<2
0
PMN (neutrophils)
<5
0
>100-10,000
>10-100
<100
<100
 early
MMN (lymphocytes)
<20
<5
<100

>100

 late
Protein
<0.3
<0.4

Normal/
0.4-1

Glucose
>2.5
>2.5

Normal/
Normal
 late
Glucose % in serum
50
>40
RBC
<2
<2
+
+/-
Gram stain
Pneumonia
Epidemiology: up to 40% are mixed; viral more common than bacterial; strep pneumoniae most common
bacterial cause (especially <5yrs); mycoplasma up to 30%
History: if neonate, ask about mother’s pre- and perinatal health including infections and fever,
premature rupture of membranes, peripartum complications, meconium; wheeze in young infant =
bronchiolitis, in child = mycoplasma
Atypical pneumonias (eg. Mycoplasma, C pneumoniae)  non-specific appearance
Staph  rapidly progressive symptoms  high fever, toxic, abscesses, cavitations, pleural effusions
C trachomatis  staccato cough, diffuse rales, no fever, sore throat
Mycoplasma  hacking dry cough, arthralgia, rash (in 10%), indolent course, Kawasaki syndrome,
erythema multiforme, Guillian Barre syndrome
B pertussis  paroxysmal coughing, gasping, colour change, URTI
Pneumococcal  round pneumonia (should have FU to ensure resolution)
If severely unwell: ?staph aureus, grp B strep
If underlying lung disease: ?Hib
Apnoeas: more common in RSV, chlamydia, B pertussis
Effusions: strep pneumoniae most common cause; also mycoplasma, Hib
Empyema, pneumatocoele, cavitation: staph aureus
Examination: toxic appearance has better sensitivity than other parts of exam; SaO2 <90% on air  risk
of treatment failure with PO amoxicillin; fever +  RR /  BS / fine crackles predicts XR positive
pneumonia with 93-96% sensitivity; fever + all 3 = 98% sensitivity; absence of  RR, respiratory
distress, rales and  BS excludes pneumonia in 100%; SOB is best sign to rule out
Bloods: blood culture +ive in <5%; NPA helpful to identify virus in younger, mycoplasma in older;
mycoplasma cold agglutinins 72-92% sensitivity
CXR: cons: may be false –ive / +ive; may be poor quality image; cost; delay; exposure to radiation; can’t
distinguish between bacterial and viral
Indications for CXR: toxic appearance with respiratory findings; <3/12 as part of septic screen; <5yrs
with T >39°C, WCC >20 and no source; ambiguous clinical findings; ?complication; not
responding to antibiotics; ?congenital lung malformation; follow up of round pneumonia;
specific exam findings suggesting pneumonia
Admission criteria: <6-12/12, toxic, altered LOC, complicated pneumonia, hypoxia, unrelieved
respiratory distress; inability to feed; co-morbidities, dehydration, not tolerating PO antibiotics, social
issues
Assessment of
the Febrile
Child
If find source, still do extensive search especially if <3/12; after fever reduction, no difference between
appearance of bacteraemic and non-bacteraemic child (fever reduction may mask signs of severe
infection); ask about birth history, peri- or neonatal complications; all criteria missed SBI in those <1/12
Rochester Criteria: if <60d and well looking, no peri-partum or prior illness, normal FBC, urine and CXR–
SBI excluded; will miss 1% SBI; least sensitive of the 3
Philadelphia Protocol: if 29-56d and well looking, no immunodeficiency, normal RBC, urine, CXR and CSF;
sensitivity 98%, specificity 44%
Boston Criteria: if 28-89d and well looking, no recent immunisations / antibiotics, WBC <20, normal
urine, CXR and CSF; >99% sensitivity
<1/12
<3/12
Investigation of
the Febrile
Child
>3/12
Appears well
FBC, blood culture, urine, CSF, CXR; stool if diarrhea; admit and give
antibiotics
Appears well
As above; but can discharge if WCC <15, urine –ive, CSF WBC <10 and
normal CXR; admit otherwise
?bronchiolitis
Still need to do urine
?viral
Still need to do urine and bloods
Appears well
Urine; discharge if negative
Appears unwell, any age
Admit and treat
Septic screen: do if: 3/12 or under
Concurrent antibiotic use and fever without focus
Toxic appearance
Bloods: WCC, ANC, CRP, procalcitonin improve prediction of SBI; CRP 75% sensitivity and specificity for
SBI
Management of
the Febrile
Child
Fever reduction: Pros:  metabolic demands; improved neurological assessment; symptomatic relief
Cons: doesn’t  febrile convulsions, fever  WBC motility and Fe, fever beneficial to
immune response,  ability to assess children with SBI
Admit for antibiotics if: <1/12 (regardless of septic screen result); <3/12 with WCC >15 or any abnormal
result on septic screen
Sepsis: 10-20ml/kg IV saline bolus until perfusion improves (stop if rales or hepatomegaly develops); if
shock not reversed, begin inotrope (use dopamine if “cold shock”, noradrenaline if “warm shock”); give
hydrocortisone if resistant to inotropes
Fever without Focus
<3/12
Amoxicillin 50mg/kg QID (TDS if <1/52)
(or ampicillin 50mg/kg QID) (to cover Listeria + Gp B strep)
+ Cefotaxime 100mg/kg loading dose  50mg/kg QID (BD if <1/52)
(to cover G-ive)
or Gentamicin 7mg/kg OD
and consider aciclovir
>3/12
Cefotaxime 100mg/kg loading dose  50mg/kg QID
Urinary Tract Infection
<3/12
CNS not
excluded
Amoxicillin 50mg/kg QID (TDS if <1/52)
+ Cefotaxime 100mg/kg loading dose  50mg/kg QID (BD if <1/52)
<3/12
CNS excluded
Amoxicillin 50mg/kg QID (TDS if <1/52) (use ceftriaxone 25mg/kg BD if penicillin allergy)
Gentamicin 7.5mg/kg OD (max 240-360mg) IV (Not as good at CNS penetration as cef)
Gentamicin 7.5mg/kg OD (max 240-360mg) IV
or Cefuroxime 25-30mg/kg/dose IV
>3/12
Antibiotic
Choice in
Paediatrics
+
Well Child
If 6-24/12, give 1x IV/IM dose ceftriaxone 50mg/kg, then discharge on PO for 10/7
(<2yr) or 7/7 (older child)
Augmentin 10mg/kg TDS PO
Or Cotrimoxazole 4mg/kg BD PO
Or Cephalexin 10mg/kg TDS PO
Meningitis
<1/12
Amoxicillin 50mg/kg QID (TDS if <1/52)
+ Cefotaxime 50mg/kg QID (BD if <1/52)
or Gentamicin 2.5mg/kg TDS (BD if <1/52)
<3/12
Amoxicillin 50mg/kg QID
+ Cefotaxime 100mg/kg loading dose  50mg/kg QID
>3/12
Cefotaxime 100mg/kg loading dose  50mg/kg QID
Or Ceftriaxone IM 100mg/kg loading dose  80-100mg/kg OD
if no IV access
Once sensitivities available: if Hib – amoxicillin; if pneumococcus / meningococcus – penicillin G,
vancomycin
Meningococcal Sepsis
<1/12
Amoxicillin 50mg/kg QID (TDS if <1/52)
+ Cefotaxime 50mg/kg QID (BD if <1/52)
?+ Gentamicin 7.5mg/kg OD (5mg/kg if <1/52)
<3/12
Amoxicillin 75mg/kg QID
+ Cefotaxime 100mg/kg loading dose  50mg/kg QID
>3/12
Cefotaxime 100mg/kg loading dose  50mg/kg QID
Or Ceftriaxone 50mg/kg BD
Or Ceftriaxone IM 100mg/kg loading dose  80-100mg/kg OD
if no IV access
Brain Abscess: fluclox 50mg/kg IV Q4hrly + cefotaxime 50mg/kg QID + metronidazole 7.5mg/kg TDS
HSV encephalitis: aciclovir <3/12 = 20mg/kg TDS <12yrs = 500mg/m2 TDS >12yrs = 10mg/kg TDS
Pneumonia
<3/12
Antibiotic
Choice in
Paediatrics
(cntd)
>3/12
>3/12,
complicated
>3/12,
unwell ++
If well
Mycoplasma
Staph
Discharge
Criteria
Amoxicillin 50mg/kg QID (TDS if <1/52)
(or ampicillin 50mg/kg QID)
+ Cefotaxime 100mg/kg loading dose  50mg/kg QID (BD if <1/52) (or gentamicin)
Amoxicillin 30-50mg/kg TDS
Or
+
Augmentin 30mg/kg TDS-QID
(ie. ?staph, lung abscess, pleural effusion)
Cefuroxime 30mg/kg TDS
Erythromycin / clarithromycin if severe (for atypicals, mycoplasma)
+
Flucloxacillin 50mg/kg QID IV (to cover staph)
Cefotaxime 50mg/kg QID IV
Amoxicillin 30mg/kg TDS PO for 5-7/7
Erythromycin 12.5mg/kg QID PO for 7-10/7
or Roxithromycin 4mg/kg BD PO
Flucloxacillin 50mg/kg QID IV
+/- Clindamycin 10mg/kg TDS-QID IV
(if not improving on amoxicillin)
(unwell, post-viral, abscesses)
In fever: Term baby; no co-morbidities; no antibiotics during illness; WCC 5-15; other investigations
normal; responsible carer; high probability of follow up
In febrile convulsion: simple seizure, now normal neurological exam, source of fever determined,
sensible parents with action plan, able to access help; consider seizure prophylaxis if prolonged
recurrent seizures