In a 1-year-old child with severe retractions and a barking cough, what is the likely diagnosis?

The likelihood of croup, also known as laryngotracheobronchitis, in a 1-year-old child presenting with severe retractions and a barking cough is quite high. This condition is characterized by inflammation of the upper airway, particularly involving the larynx, which leads to the classic 'barking' cough sound. In addition to a distinctive cough, croup often presents with inspiratory stridor (a high-pitched wheezing sound heard during inhalation) and retractions, which occur as the child struggles to breathe.

Croup is most common in young children, typically between the ages of 6 months and 5 years, and is often triggered by viral infections, such as parainfluenza viruses. The presentation aligns with a viral cause, making it the most plausible diagnosis given the symptoms described. Prompt recognition and management can help alleviate symptoms and prevent complications related to airway obstruction.

In contrast, pneumonia would more typically present with features such as fever, cough with purulent sputum, and respiratory distress, but would not specifically identify the barking cough associated with croup. Bronchitis usually occurs with a productive cough, possibly with wheezing, and is less common in this age group. Asthma can present with