What would a lateral neck X-ray show in a child with croup?

In a child diagnosed with croup, a lateral neck X-ray typically reveals characteristic findings, specifically haziness in the subglottic area along with the steeple sign. The steeple sign refers to the appearance of the narrowing of the airway at the level of the subglottis, which closely resembles the shape of a church steeple. This is due to the inflammation and edema of the tissues surrounding the airway, which is common in viral croup.

The presence of this sign is indicative of croup and helps differentiate it from other causes of airway obstruction. Croup is most often caused by viral infections that lead to inflammation in the larynx, trachea, and bronchi, primarily affecting the subglottic region.

Other options do not accurately represent the typical findings associated with croup on a lateral neck X-ray. For instance, the normal airway structure would not accurately portray the typical appearance observed in patients with croup. Similarly, thickening of the tracheal wall may indicate other conditions but is not a hallmark of croup. Lastly, an enlarged thymus shadow is not relevant in the context of croup and would be indicative of different pathology. Thus, the haziness in the subgl