Resp - CROUP

Question 1

Definition

Answer 1

Acute laryngotracheobronchitis = infective upper respiratory tract infection causing oedema in the larynx
- commonly caused by parainfluenza virus

Question 2

Epidemiology

Answer 2

• Children: 6 months - 3 years old
• Peak incidence is at 3 years old
• Common in Autumn and Spring
• More common in boys
• Prematurity: particularly in children with children with a Hx of chronic lung disease of prematurity
• Underlying respiratory disease

Question 3

Pathophysiology

Answer 3

Mucosal inflammation anywhere between the nose and the trachea + infiltration of white blood cells
- characteristic barking cough whilst inflammation, laryngeal oedema and secretion can lead to stridor and upper airway obstruction

Question 4

Aetiology

Answer 4

Causative organisms:
- Parainfluenza virus (MC)
- Adenovirus
- Influenza
- Rhinovirus
- Respiratory Syncytial Virus (RSV)
- Enterovirus
Bacterial croup such as laryngeal diphtheria exists except it is significantly less common

Question 5

Signs and symptoms

Answer 5

Symptoms:
- Barking cough worse at night
- Hoarse voice
- Difficulty in breathing
- Coryza
Signs:
- Pyrexia
- Inspiratory Strider
- Respiratory distress : intercostal and subcostal recession, tracheal tug, nasal flaring, accessory muscle use

Question 6

Examination and history

Answer 6

• 1-4 days history of non-specific rhinorrhea (thin, nasal discharge), fever and barking cough
• Worse at night
• Stridor
• Decreased bilateral air entry
• Tachypnoea
• Costal recession

Question 7

Respiratory red flags

Answer 7

• Drowsiness
• Lethargy
• Cyanosis
• Tachycardia
• Laboured breathing

Question 8

Diagnosis

Answer 8

Clinical diagnosis
- Neck X-ray AP = STEEPLE SIGN
- Lateral X ray = THUMB SIGN
- FBC, CRP U+E
- CXR to exclude foreign body

Question 9

Treatment

Answer 9

Mild: Oral dexamethasone (0.15mg/kg) and discharge
Moderate/Severe:
- Admission to hospital + Oxygen if required
- Single dose oral DEXAMETHASONE 0.15mg/kg
- Nebulised budesonide if unable to tolerate oral dexamethasone
- Nebulised adrenaline: airway obstruction for relief of severe symptoms
- Monitor for needed ENT intervention if suspected airway blockage = intubation and ventilation

Question 10

Complications

Answer 10

• Dehydration due to reduced fluid intake
• Superinfection: pneumonia
• Airway obstruction