Laryngo-tracheal
Infections
Stridor
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It is the noise caused by obstruction of
airflow due to narrowing in respiratory tract
It may be inspiratory / biphasic /expiratory
Inspiratory stridor alone indicates that the
lesion is at vocal cord level or above
An expiratory phase occurs when the
tracheal lumen is also narrowed by oedema
or inflammation
Acute Laryngeal infections in
childhood
Acute Epiglottitis
 Laryngotrachealbronchitis
 Bacterial
Laryngotrachealbronchitis
 Diphtheria
 Conditions which mimic laryngeal
infections
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Acute Epiglottitis
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Most frightening pediatric emergency
If unrecognized it can kill the child
Haemophilus influenzae type B , is the
causative organism in most cases
The disease is concentrated maximally on
the epiglottis but the inflammation may
involve whole supraglottic compartment
Most cases seen between 1 and 6 years of
age, peak incidence between ages 3 and 4
Clinical features
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Sudden transformation of a fit child into one who is
desperately ill, within a few hours
Classical features:
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A fit child c/o sore throat which intensifies, with in half and
hour dysphagia reported
Inspiratory stridor develops and within 2 hours child
becomes critical
Child sits up and leans forward
Saliva is dribbling due to absolute dysphagia
Voice is muffled
As time goes child becomes quiet and respiratory distress
appears to lessen.
An an ominous sign: respiratory & cardiac arrest imminent
http://www.aic.cuhk.edu.hk/web8/epiglottitis%20picture.htm
http://www.aic.cuhk.edu.hk/web8/supraglottitis.htm
Management
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It is a surgical emergency
Examination of throat by tongue depressor is
particularly dangerous- sudden respiratory
obstruction may occur
Lateral X-ray of neck may show classical
‘thumb’ sign of swollen epiglottis
If the clinical situation suggests that the
diagnosis is epiglottitis , there is no point in
confirming it what might turn out to be fatal
X-ray
www.learningradiology.com/archives04/COW%2010..
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The child is shifted to OT and anesthetized in
upright position
Laryngoscope inserted & diagnosis confirmed
An appropriate size orotracheal tube inserted
Otherwise rigid bronchoscope used to secure
airway
Tracheostomy / nasotracheal tube
Culture swabs taken from epiglottis
Nasogastric tube inserted for feeding
I/V line established
Best Clinical Practice
Adults with suspected acute
epiglottitis should be admitted and
airway closely monitored
 Patients should be treated with I/V
second- or third-generation
cephalosporins and 100% humidified
oxygen
 Airway obstruction should be treated
early, ideally by intubation
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Laryngotracheobronchitis (Croup)
As name suggests it involves larger
proportion of respiratory tract
 Area of maximum impact is sub-glottis
 An acute illness with hoarseness, a
barking cough, stridor and varying
degree of respiratory distress
 Affects young children (6 months to 3
years)
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In most cases causative organism is
paramyxovirus, para-infleunza virus
type I and type II
 In adults it may also occur from herpes
simplex, cytomegalovirus & influenza
virus
 Adult croup is rare, more severe &
impaired immunity should always be
considered
 The key feature is sub-glottic oedema
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Investigations
Direct viral antigen detection by
sampling mucus from nasopharynx
 A plain neck radiograph may show
narrowing of the subglottis (steeple
sign) and ballooning of hypopharynx
 Chest X-ray to exclude collapsed lobes
or meditational shift
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Management
Oxygen, steroids and nebulized
epinephrine should be administered
 Monitor airway and oxygen saturation,
consider endotracheal intubation if
necessary
 Broad spectrum antibiotics to cover
secondary infection
 No evidence to support antiviral agents
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Best Clinical Practice
Adult croup is rare but rapidly progressive
 Once suspected patient should be
admitted
 Larynx inspected by flexible laryngoscope
 Broad-spectrum ABx to prevent bacterial
infection
 If the airway deteriorates patient should be
intubated and ventilated
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Bacterial Laryngotrachealbronchitis
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May be a separate disease or be caused by
secondary bacterial infection of viral
laryngotrachealbronchitis
Also called bacterial tracheitis since it
involves trachea predominantly
Much more severe illness and much less
common
More severe respiratory obstruction and
artificial airway is often needed
Tracheostomy preferred over intubation
Diphtheria
Caused by Corynebacterium
diphtheriae
 Spreads by droplet infection
 Affects non-immunised children and
susceptible adults particularly elderly
 Usual site of infection is the tonsils and
fauces but it can also occur in nasal
cavities or spread to larynx
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Clinical Features
Severe sore throat, malaise, pyrexia
 Examination of throat shows
characteristic grey membrane in
oropharynx which may spread to
larynx
 Enlarged tender cervical lymph nodes
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Investigations
A swab from throat for C/S
 A sample of grey membrane for
screening
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Management
Treat with benzyl penicillin and
antitoxin
 Acute obstruction should be managed
with intubation
 Complications:
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The diffusible exotoxin has predilection
for cardiac and renal tissues
 Neurological complications soft palate
paralysis, diaphragm & EOM
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Conditions which mimic laryngeal
infections in childhood
Foreign bodies
 Peritonsillar abscess
 Retropharyngeal Abscess
 Infectious mononucleosis
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Infectious mononucleosis
A common disease often sub-clinical
or mild
 Caused by Epstein-Barr virus
 Spread is usually transfer of infected
saliva during kissing
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Clinical Features
Acute sore throat with large infected
tonsils
 Cervical lymphadenopathy with grossly
enlarged bilateral lymph nodes
 Fever, Malaise
 There may also be palatal petechiae,
oral ulceration, splenomegaly and
hepatomegaly
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www.answers.com/topic/diphtheria
Complications
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Gross swelling of tonsils and adenoids
causes airway obstruction, but inflammation
and ulceration can also extend to larynx
The severity of laryngeal involvement may
be masked by upper airway obstruction
Splenic rupture
CNS complications like encephalitis,
meningitis, CN palsies
Immune deficiency and HIV status be looked
into
Investigations
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Full Blood count
Heterophil antibody test: Heterophil antibodies are
antibodies that are stimulated by one antigen and react with an
entirely unrelated surface antigen present on cells from different
mammalian species
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Specific EBV serology
HIV testing
Management
I/V fluids
 Analgesia
 In serious infections antibiotics,
steroids and acyclovir should be
considered
 Ampicillin / amoxycillin are best
avoided for fear of inducing a
maculopapular rash
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