When Should the Differential Diagnosis of Croup Be Reconsidered?

Croup is a common pediatric illness characterized by a barking cough and inspiratory stridor, most often caused by viral infection. However, differential diagnoses should be considered when patients present with atypical symptoms or fail to respond to standard treatment. We report the case of a previously healthy three-year-old boy who presented with a three-day history of fever and a one-day history of barking cough. He was diagnosed with croup and treated with nebulized epinephrine and oral dexamethasone but showed minimal clinical improvement. His symptoms progressed to include a markedly severe sore throat and odynophagia. Contrast-enhanced CT revealed a 10-mm laryngeal lesion causing significant airway narrowing. Intubation was performed under sevoflurane anesthesia. Video laryngoscopy revealed a space-occupying lesion in the vestibular fold. Laryngeal fluid cultures confirmed Streptococcus pyogenes, establishing the diagnosis of a laryngeal abscess. The patient remained intubated for five days and received intravenous ampicillin/sulbactam for three weeks. Follow-up ultrasound one month later demonstrated complete resolution. In children with suspected croup who present with atypical features, such as severe sore throat, prolonged illness, or poor response to treatment, deep neck infections, including laryngeal abscess, should be considered. Early recognition and timely intervention are crucial for achieving favorable outcomes.