A 4-month-old boy is brought to the office for "noisy breathing." The patient's parents first noticed a harsh sound when he cried at age 2 weeks, but it has gotten louder over the past month, especially when he is lying on his back. The noise seems to improve when the patient is held upright or during "tummy time." He does not appear to have labored breathing and has never turned blue. The patient has had occasional, small spit-ups after feeds but has been growing well along the 60th percentile for weight. He was born at full term without complications during pregnancy or labor and delivery. On physical examination, the patient has inspiratory stridor when he is supine that improves when he is prone. The remainder of the examination is normal. Which of the following would confirm the most likely diagnosis for this patient?

Question

A 4-month-old boy is brought to the office for "noisy breathing."  The patient's parents first noticed a harsh sound when he cried at age 2 weeks, but it has gotten louder over the past month, especially when he is lying on his back.  The noise seems to improve when the patient is held upright or during "tummy time."  He does not appear to have labored breathing and has never turned blue.  The patient has had occasional, small spit-ups after feeds but has been growing well along the 60th percentile for weight.  He was born at full term without complications during pregnancy or labor and delivery.  On physical examination, the patient has inspiratory stridor when he is supine that improves when he is prone.  The remainder of the examination is normal.  Which of the following would confirm the most likely diagnosis for this patient?

Quizplus · Accepted Answer

11ec25c8_d8c2_baed_bc81_8fb6b47a8146_MD0003_00 Laryngomalacia, which causes chronic stridor in infants, is typified by "floppy" supraglottic structures that collapse during inspiration. Proposed pathophysiologic etiologies include laryngeal hypotonia (due to delayed maturation or neuromuscular disorder), redundant supraglottic soft tissue, and inflammation (due to reflux). Laryngomalacia Stridor from laryngomalacia usually begins in the neonatal period and is loudest at age 4-8 months. Presentation includes inspiratory stridor that is worse in the supine position and exacerbated by feeding or upper respiratory illnesses; prone positioning improves symptoms. The diagnosis is confirmed with visualization of the larynx, typically by flexible fiberoptic laryngoscopy. Findings include an omega-shaped (Ω) epiglottis and collapse of the supraglottic structures during inspiration. Gastroesophageal reflux (GER) treatment often improves symptoms; it is unclear whether GER causes laryngomalacia or is due to a common underlying mechanism (eg, neuromuscular disorder). Most infants with laryngomalacia will feed, grow, and ventilate normally with spontaneous resolution of stridor by age 18 months. Infants with feeding difficulties, tachypnea, cyanosis, or failure to thrive may require surgery to remove redundant supraglottic tissues. (Choice A) Chest radiographs can identify anterior mediastinal masses and radiopaque foreign bodies, both of which can cause stridor. Mediastinal masses (eg, lymphoma) also present with systemic symptoms (eg, fever, weight loss, lymphadenopathy), and airway foreign bodies present with a more acute symptom onset; these symptoms are not seen in this patient. (Choices B and F) Retropharyngeal abscesses occur in toddlers and present with fever, dysphagia, neck pain, and stridor. Lateral neck radiographs can demonstrate thickening of the prevertebral space. CT scan of the neck can better define extension of the abscess to nearby structures. This patient does not have symptoms suggestive of infection. thickening of the prevertebral space (Choices D and E) Vascular rings occur when an anomalous branch of the aortic arch or pulmonary artery encircles the trachea and esophagus. They may cause biphasic or expiratory stridor due to tracheal compression and feeding difficulties due to esophageal compression. A barium swallow can identify indentations of the esophagus, and the diagnosis can be confirmed with contrasted CT scan or MR angiography. Vascular rings Educational objective: Laryngomalacia presents in infants with inspiratory stridor that worsens in the supine position and improves in the prone position. Laryngoscopy shows collapse of the supraglottic structures during inspiration. Concurrent gastroesophageal reflux should be treated. Laryngomalacia usually resolves spontaneously by age 18 months. References: Laryngomalacia: disease presentation, spectrum, and management. (http://www.ncbi.nlm.nih.gov/pubmed/22518182) Laryngomalacia. (http://www.ncbi.nlm.nih.gov/pubmed/23905826) Laryngomalacia: is there an evidence base for management? (http://www.ncbi.nlm.nih.gov/pubmed/29067893) A systematic review of laryngomalacia and acid reflux. (http://www.ncbi.nlm.nih.gov/pubmed/22745201)

A 4-Month-Old Boy Is Brought to the Office for "Noisy