Acute Infections of the Larynx

Laryngeal infection in childhood causes airway obstruction; the cardinal symptom is stridor. Croup/ laryngotracheobronchitis is the most common (90%) cause of acute airway obstruction in children. Epiglottitis is the next most common infective cause but is now seen much less frequently due to the Haemophilus influenza B (Hb) vaccine. The organism responsible for causing epiglottitis is S. Pneumonia.

We will now discuss each in detail. This topic is very high-yield and beneficial for every ENT specialist.

Acute Laryngitis

When the disease lasts < 4 weeks, it is acute laryngitis. The inflammation in the larynx could be secondary to an infectious cause or a non-infectious cause. Infective causes could be bacterial infection and viral infection, which predominantly account for infectious forms of laryngitis. Infective type usually follows the upper respiratory tract infection, and viral etiology is the most common attributable cause. There could be superadded bacterial infections. There can be an association between exanthematous fever and whooping cough.

Non-infective causes can be vocal abuse and allergy. It can be secondary to chemical burns to the larynx. It can happen due to laryngeal trauma and endotracheal intubation. Another common cause is gastroesophageal reflux disease.

Symptoms of Acute Laryngitis

• Fever: associated with infectious type only
• There may be hoarseness that may lead to a complete loss of voice
• Discomfort or pain in the throat after talking
• Dry and irritating cough: worse at night
• Foreign body sensation in the throat

Investigations of Acute Laryngitis

There is no need to diagnose acute laryngitis. History and physical examination is enough to diagnose the condition.

Treatment of Acute Laryngitis

• Vocal rest: This is the most important single factor.
• Avoidance of smoking and alcohol.
• Steam inhalations: Soothing and loosen viscid secretions.
• Cough sedative
• Antibiotics: When there is secondary infection with fever or purulent expectoration.
• Analgesics.
• Steroids: Useful in laryngitis following thermal or chemical burns.

Also Read: Inflammatory Disorders and Autoimmune Diseases of Larynx

Acute Epiglottitis/Supraglottic Laryngitis

Structures that may be involved:

• Epiglottis 
• Aryepiglottic folds
• Arytenoids
• False Cords

Marked edema of these structures may obstruct the airway.

Etiology of Acute Epiglottitis/Supraglottic Laryngitis

It affects children 2-7 years of age but can also affect adults. The most common organism responsible for this condition in children is Streptococcus pneumonia.

Symptoms Of Acute Epiglottitis/Supraglottic Laryngitis

• High-grade fever: The patient may deteriorate rapidly
• Respiratory symptoms: Inspiratory Stridor
• The child utilizes the position to get air, which is called the tripod position.
• Dysphagia/Odynophagia.
• Drooling of saliva.
• Vocal cords and subglottis are spared: No hoarseness of voice and No cough.

Examination of Acute Epiglottitis/Supraglottic Laryngitis

Ideally examination should be avoided. Even the use of a tongue depressor to visualize the oropharynx it may precipitate laryngospasm. Crying will worsen the stridor.

Diagnosis of Acute Epiglottitis/Supraglottic Laryngitis

• X-ray (lateral view): Thumb sign. 
• CT can also be done

Treatment of Acute Epiglottitis/Supraglottic Laryngitis

• Require Hospitalisation
• Antibiotics: Ampicillin or 3^rd Generation cephalosporin
• Steroids: Used to relieve edema and inflammation
• Racemic adrenaline nebulization can be given. It consists of about 1:1000 adrenaline mixed with 3 ml of 0.9% saline. 
• Adrenaline is responsible for causing vasoconstriction: This will cause shrinkage of the mucosa. Airway edema gets relieved.

Acute Laryngeal Tracheal Bronchitis SYN Croup

It is an inflammatory condition of the larynx, trachea, and bronchi, more common than acute epiglottitis. Para influenza types 1 and 2 are responsible for it. Other viruses, like respiratory syncytial virus (RSV), types A and B and rhinovirus, can also cause it. It usually affects children between 6 months and 3 years of age. Male children are more often affected.

A secondary bacterial infection could occur, followed by a viral infection.

Pathology of Croup

• There is a large amount of loose areolar tissue in the subglottic region. This results in swelling, which causes respiratory obstruction and stridor. Along with this, thick, tenacious secretions and crusts completely block the airway. 
• If there is a 1 mm reduction in the airway because of edema and inflammation, lumen gets compromised by 50%.
• The child will have biphasic stridor.
• Digestive symptoms are less frequent in occurrence.
• There is involvement of the subglottis, trachea, and vocal cord. All of the three are involved, and this will result in a change in voice.
• The child will have a barking seal cough.
• Epiglottitis has a slow progression.

Diagnosis of Croup of epiglottitis

• Avoid examination.
• An X-ray will show the narrowing of the subglottis. It would resemble the steeple of the church.

Treatment of Croup

• The child’s treatment should be done at the hospital. 
• The scoring system helps to understand the severity of the disease. Children with high scores need to be admitted to the hospital. The scoring system is called the Westley Croup Score. 
• Antibiotics can be given.
• Racemic adrenaline nebulization can also be given.
• Steroids and bronchodilators are given.

Westley Croup Score

In the Westley croup score, if the final score is less than two, it is called mild, 3-7 score is moderate, and an 8 to 11 score is severe. More than 12 tells that the child is going into impending airway obstruction. For mild patients, give symptomatic therapy and a single dose of oral dexamethasone. For moderate patients, similar things need to be done; just add racemic adrenaline nebulization.  In Severe cases, Children are given the same treatment as above, given steroids in IV or IM dose and repeated adrenaline nebulization.

In impending airway obstruction, the child is required to be kept in the ICU. Treatment is given the same as above. Be ready for intubation and tracheostomy.

Bacterial Laryngotracheal Bronchitis

• It is also called pseudomembranous croup, bacterial tracheitis, membranous laryngotracheobronchitis, and neonatal necrotizing tracheobronchitis.
• Bacterial tracheitis is a rare but potentially life-threatening cause of upper airway obstruction in children.
• A severe form of laryngotracheobronchitis is characterized by the presence of profuse mucopurulent secretions with sloughing of the respiratory epithelium.
• Secretions are adherent, are not effectively cleared by coughing, and may occlude the airway, causing respiratory compromise.
• Classically, the child with bacterial tracheitis appears toxic with high fevers and worsening stridor that fails to respond to treatment with steroids and nebulized epinephrine.
• It typically affects older children between the age of 4-8 years. 
• It is again more common in boys and girls.
• There is increased susceptibility in children with Down syndrome or immunodeficiency.

Diagnosis of Bacterial Laryngotracheal Bronchitis

• Diagnosis is only confirmed by Endoscopy. 
  • Thick secretions and debris in the trachea can extend into the bronchi. 
  • There may be pseudomembranes in the subglottis and trachea. 

Treatment of Bacterial Laryngotracheal Bronchitis

• Treatment requires teamwork, and the team should involve the primary care physician, the pediatrician, the pediatric otolaryngologist, the pediatric anesthetic, and the pediatric intensive care physician. 
• Direct laryngotracheobronchoscopy under general anesthesia and removal of all tracheal secretions with pulmonary toileting is mandatory.
• The airway has to be secured with an endotracheal tube and airway toileting.
• Repeated endoscopy may be required.
• Give parenteral antibiotics.

Complications in Bacterial Laryngotracheal Bronchitis

• Airway stenosis
• Acute respiratory distress syndrome
• Respiratory failure
• Toxic shock syndrome
• Anoxic encephalopathy
• Death

Laryngeal Diphtheria

• It is caused by the bacteria called Corynebacterium diphtheriae.
• It is secondary to faucial diphtheria.
• Affects children below 10 years of age.

Pathology of Laryngeal Diphtheria

• The formation of a tough pseudomembrane over the larynx and trachea completely obstructs the airway.
• Exotoxin will liberate an inflammatory membrane. It can cause bacterial myocarditis and neurological complications.

Diagnosis of Laryngeal Diphtheria

• Confirmed by smear and culture of Corynebacterium diphtheriae.
• Albert Stain: Chinese Letter Appearance

Symptoms of Laryngeal Diphtheria

• High-grade fever.
• Hoarse voice, croupy cough, inspiratory stridor, increasing dyspnoea with marked upper airway obstruction.
• Grey white membrane on the tonsil, pharynx, soft palate, larynx, and trachea.
• It is a pseudomembrane. 
• It is adherent, and its removal can cause bleeding.
• It leaves a bleeding surface.
• Cervical Lymphadenopathy: “Bull neck”

Treatment of Laryngeal Diphtheria

• It should be treated very quickly.
• Start diphtherial antitoxin. 
• Steroids and antibiotics can also be used.
• Do a tracheostomy or direct laryngoscopy to remove the membrane.

Complications of Laryngeal Diphtheria

• Asphyxia and death due to airway obstruction.
• Toxic myocarditis and circulatory failure.
• Palatal paralysis with nasal regurgitation.
• Laryngeal and pharyngeal paralysis.

Oedema of the Larynx

It involves the supraglottic and subglottic regions where laryngeal mucosa is loose.

Aetiology of Oedema of the Larynx

Symptoms of Oedema of the Larynx

• Airway obstruction
• Biphasic stridor
• Indirect laryngoscopy shows edema of supraglottic or subglottic structure.
• Children may require direct laryngoscopy to see the edema.

Treatment Of Oedema of the Larynx

• Intubation of the larynx or tracheostomy.
• Adrenaline injection can be given if it is allergic or angioneurotic edema.
• Steroids are useful when edema is due to allergy, trauma or post radiation.

Airway Management in Laryngeal Infection

• Do intubation to get access to the airway.
• You can do a nasotracheal intubation, or you can do an orotracheal intubation.
• Nasotracheal intubation is better tolerated in children.
• If intubation is not done, then a tracheostomy can be performed.
• Cricothyrotomy may offer you emergency access to the airway.

Frequently Asked Questions:

Q: Cervical Lymphadenopathy, known as Bull neck, is seen in which disease?

Answer: Laryngeal Diphtheria

Q: What treatment needs to be done for Croup in a pediatric patient?

Answer: The child’s treatment should be done at the hospital. The scoring system helps to understand the severity of the disease. Children with high scores need to be admitted to the hospital. The scoring system is called the Westley Croup Score. Antibiotics can be given.

Q: What is the causative organism of  Laryngeal Diphtheria?

Answer: Laryngeal Diphtheria is caused by the bacteria called Corynebacterium diphtheriae.

Hope you found this blog helpful for your ENT residency Larynx preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs.