Recognised cause of stridor in newborn-
**Core Concept**
Laryngomalacia is a congenital condition characterized by the softening of the cartilage in the larynx (voice box), leading to partial airway obstruction. This condition is a common cause of stridor in newborns, which is a high-pitched sound heard during breathing.
**Why the Correct Answer is Right**
Laryngomalacia is caused by the incomplete cartilaginous support of the airway, leading to dynamic airway obstruction. The floppy epiglottis and supraglottic tissues collapse inward during inspiration, causing the airway to narrow and produce the characteristic stridor sound. This condition is often associated with a soft and high-pitched cry.
**Why Each Wrong Option is Incorrect**
**Option A:** Laryngopharyngeal reflux is a condition characterized by the reflux of stomach contents into the laryngopharynx, which can cause symptoms such as hoarseness and cough, but it is not a recognized cause of stridor in newborns.
**Option B:** Tracheomalacia is a condition characterized by the softening of the cartilage in the trachea, which can cause symptoms such as wheezing and respiratory distress, but it is not a recognized cause of stridor in newborns.
**Option C:** Subglottic stenosis is a condition characterized by the narrowing of the airway below the vocal cords, which can cause symptoms such as stridor and respiratory distress, but it is not a recognized cause of stridor in newborns.
**Clinical Pearl / High-Yield Fact**
Laryngomalacia is a common cause of stridor in newborns, and it often presents with a soft and high-pitched cry. It is essential to distinguish laryngomalacia from other causes of stridor, such as subglottic stenosis, which may require surgical intervention.
**Correct Answer:** D. Laryngomalacia.