Tonsils & Adenoids

Tonsils and adenoids perform several critical functions for immune health:

• Pathogen Defense: Trap bacteria and viruses entering through the oral and nasal cavities
• Immune Cell Production: Generate lymphocytes (B-cells and T-cells) to fight infection
• Immune Memory Formation: Help the body recognize and respond to pathogens in the future
• Barrier Function: Protect respiratory and digestive tracts from invading microbes
• Interaction with Other Lymphoid Tissues: Work alongside the thymus, spleen, and lymph nodes to coordinate immunity

Key Takeaway

Tonsils and adenoids are essential lymphatic structures that help the body detect, trap, and respond to pathogens, supporting both innate and adaptive immunity.

Basic Structure

• Composed of lymphoid tissue covered by mucous membrane
• Contain crypts that trap and expose antigens to immune cells
• Highly vascularized to support immune cell trafficking

Major Regions

• Palatine Tonsils: Located on either side of the oropharynx; visible at the back of the throat
• Pharyngeal Tonsil (Adenoids): Located on the roof of the nasopharynx behind the nose
• Lingual Tonsils: Located at the base of the tongue
• Tubal Tonsils: Located near the openings of the Eustachian tubes

Nerves & Blood Supply

• Sensory Innervation: Glossopharyngeal nerve (CN IX) and vagus nerve (CN X)
• Blood Supply: Tonsillar branch of the facial artery, ascending pharyngeal artery
• Venous Drainage: Pharyngeal venous plexus

Key Takeaway

Tonsils and adenoids are strategically positioned to detect and respond to airborne and ingested pathogens, forming a critical component of mucosal immunity.

• Tonsils and adenoids are most active during childhood and shrink with age
• Crypts in tonsils increase surface area for immune surveillance
• Adenoids are not visible without specialized instruments
• Over 70% of upper respiratory infections in children involve these lymphoid tissues
• Chronic enlargement may affect breathing or swallowing

• Tonsillitis: Inflammation of the tonsils due to viral or bacterial infection
• Adenoiditis: Inflammation of the adenoids, often causing nasal obstruction
• Sleep Apnea: Enlarged tonsils or adenoids can block airways during sleep
• Peritonsillar Abscess: Complication of severe tonsillitis causing pus formation
• Chronic Infection: Recurrent infections may require surgical removal (tonsillectomy/adenoidectomy)

• Frequent sore throat or infections
• Difficulty breathing through the nose
• Snoring or sleep disturbances
• Swollen or tender throat lymphoid tissue
• Persistent bad breath

Source: Sam Webster