Laryngo-tracheal Infections

Stridor

 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

Acute Epiglottitis

 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

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Clinical features

Sudden transformation of a fit child into one who is desperately ill, within a few hours Classical features:        A fit child c/o sore throat hour dysphagia reported which intensifies, with in half and Inspiratory stridor develops becomes critica l and within 2 hours child Child sits up and leans forward Saliva is dribblin g due to absolute dysphagia Voice is muffled As time goes child becomes quiet appears to lessen .

and respiratory distress 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

 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

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www.learningradiology.com/archives04/COW%2010 ..

 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

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)

 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

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

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

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

Bacterial Laryngotrachealbronchitis

 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

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

Investigations

 A swab from throat for C/S  A sample of grey membrane for screening

Management

 Treat with benzyl penicillin and antitoxin  Acute obstruction should be managed with intubation  Complications:  The diffusible exotoxin has predilection for cardiac and renal tissues  Neurological complications soft palate paralysis, diaphragm & EOM

Conditions which mimic laryngeal infections in childhood

 Foreign bodies  Peritonsillar abscess  Retropharyngeal Abscess  Infectious mononucleosis

Infectious mononucleosis

 A common disease often sub-clinical or mild  Caused by Epstein-Barr virus  Spread is usually transfer of infected saliva during kissing

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

www.answers.com/topic/diphtheria

Complications

 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

 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  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