Croup Pathophysiology Quiz

The smaller diameter of an infant's airways makes them more prone to airway narrowing during croup, contributing to the characteristic barking cough and difficulty breathing.

Croup, a common respiratory infection, typically affects children between 6 months and 5 years old.

Parainfluenza virus is the most common culprit behind croup, although other respiratory viruses such as RSV and influenza may also play a role.

Croup's primary symptom is a distinctive barking cough, which occurs due to swelling and narrowing of the airways. This narrowing can lead to a high-pitched whistling sound (stridor) when breathing.

Exposure to respiratory droplets from coughing or sneezing, direct contact with contaminated surfaces, and even airborne transmission can spread croup.

The most frequent cause of croup is the parainfluenza virus. Other viruses that can cause croup include RSV, influenza, adenovirus, COVID-19, and human metapneumovirus.

The virus infects the larynx, trachea, and bronchi, leading to inflammation and swelling of the subglottic space, causing a narrowing of the upper airway.

The narrowing of the airway causes the characteristic 'barking cough' and stridor, a high-pitched wheezing sound heard during inhalation.

Inflammation leads to mucosal edema and thick mucus production, further obstructing the airway. This increases the work of breathing and can lead to respiratory distress.

The smaller diameter of the subglottic region in children makes them more susceptible to airway obstruction than adults. As the airway narrows, children may experience retractions and prolonged inhalation.

Croup spreads through respiratory droplets from coughing, sneezing, or direct contact with contaminated surfaces, and potentially airborne transmission.

Children aged 6 months to 5 years are most susceptible to croup.