A 6-week-old infant has inspiratory stridor that is worse when supine and during feeds, and improves when placed prone. The cry is normal and there is no cyanosis. Direct laryngoscopy shows inward collapse of the supraglottic structures on inspiration. What is the most likely diagnosis?
- A Congenital subglottic stenosis
- B Bilateral vocal cord paralysis
- C Laryngomalacia ✓
- D Tracheomalacia
Correct answer: C. Laryngomalacia
Explanation
Laryngomalacia is the most common congenital laryngeal anomaly and the commonest cause of stridor in neonates. The hallmark is inspiratory stridor that worsens supine, during feeding and with agitation, and eases in the prone position, caused by immature supraglottic cartilage collapsing inward on inspiration. Vocal cord paralysis produces a weak or hoarse cry with biphasic stridor, and subglottic stenosis gives biphasic rather than purely inspiratory stridor, so both are excluded.
Reference: Cummings Otolaryngology: Head and Neck Surgery, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.