Question 1: The most likely cause of persistent snoring and mouth breathing in a child is:
- A. Tonsillar enlargement
- B. Adenoid enlargement (Correct Answer)
- C. Croup
- D. Paranasal sinus polyp
Explanation: ### Explanation
**Correct Option: B. Adenoid Enlargement**
The adenoids (nasopharyngeal tonsils) are located in the roof and posterior wall of the nasopharynx. In children, physiological hypertrophy occurs between ages 3 and 7. When pathologically enlarged, they obstruct the posterior choanae, leading to **obligate mouth breathing** and **snoring** due to vibration of the soft palate. This is the most common cause of pediatric nasal obstruction. Chronic obstruction leads to the characteristic "Adenoid Facies" (dull expression, open mouth, crowded teeth, and high-arched palate).
**Analysis of Incorrect Options:**
* **A. Tonsillar enlargement:** While palatine tonsil hypertrophy can cause snoring and Obstructive Sleep Apnea (OSA), it primarily affects the oropharynx. It is rarely the *sole* cause of persistent mouth breathing unless accompanied by adenoid hypertrophy.
* **C. Croup (Laryngotracheobronchitis):** This is an acute inflammatory condition presenting with a "barking" cough, inspiratory stridor, and hoarseness. It is not a cause of chronic, persistent snoring or mouth breathing.
* **D. Paranasal sinus polyp:** While polyps cause nasal obstruction, they are relatively rare in children. If present, they are often associated with Cystic Fibrosis or Kartagener’s syndrome. Adenoid hypertrophy is statistically far more common in the pediatric age group.
**High-Yield Clinical Pearls for NEET-PG:**
* **Investigation of Choice:** X-ray soft tissue nasopharynx (Lateral view) shows narrowing of the nasopharyngeal air space.
* **Gold Standard Investigation:** Diagnostic nasal endoscopy.
* **Associated Condition:** Adenoiditis often leads to **Eustachian tube dysfunction**, resulting in Otitis Media with Effusion (Glue Ear).
* **Treatment:** Adenoidectomy is indicated if there is persistent mouth breathing, sleep apnea, or recurrent otitis media.