What 2 classic radiographic findings are exemplified in these images?

What clinical diagnoses are they individually pathognomonic for? What clinical presentations would you expect?




Croup (A)

Occurs most commonly in children aged 1-6 yrs, with peak incidence at 18 months. Also known as larygotracheitis. Most frequently caused by parainfluenza virus, with a usual presentation of stridor and sore throat and barking cough. On exam, the child may have coryza, hoarse voice, and pharyngeal inflammation. Up to 50% of AP soft tissue neck XR can show a “steeple sign” which is indicative of subglottic narrowing. Treatment involves humidified O2, bronchodilators, and racemic epinephrine, and corticosteroids.

Epiglottitis  (B)

Inflammatory condition (usually infectious) of the epiglottis and perigottic folds. Previously caused most commonly by H. influenza type B (Hib), but incidence has decreased dramatically due to vaccination. Other common bacterial etiologies are Group A Streptococcus and S. Pneumoniae. Presentation involves 1-2 days prodromal period, followed by high fever, stridor, drooling, dysphagia, pooling of secretions, dyspnea. Patient often prefers an erect or tripod position. Neck radiographs can aid in the diagnosis, in which you will see a “thumbprint sign” on lateral neck XR. This sign is formed by the swollen epiglottis obliterating the vallecula. Fiberoptic laryngoscopy also provides diagnostic confirmation. Treatment includes airway protection, Ceftriaxone, and usually ICU level of care.