The pharyngeal tonsils are specialized masses of lymphoepithelial tissue, which are part of the body’s overall defense network. Positioned as immune sentinels, they monitor the air and food entering the body. Their primary role is to detect and filter pathogens before they can spread into the respiratory or digestive systems.
Precise Location and Alternate Name
The pharyngeal tonsil is a single mass of tissue located high in the throat, specifically in the upper region known as the nasopharynx. This area is situated directly behind the nasal cavity and above the soft palate. The pharyngeal tonsil is more commonly known as the adenoid.
It is located on the roof and posterior wall of the nasopharynx, the segment of the throat connecting to the nasal passages. Unlike the palatine tonsils, the adenoid is not visible by looking into the mouth. It is typically largest in early childhood, reaching maximum size around age five, and naturally begins to shrink around age seven, becoming small in adult life.
Function within the Immune System
The pharyngeal tonsil is an important part of Waldeyer’s ring, which is a circular arrangement of lymphoid tissue surrounding the entrance to the pharynx. This anatomical positioning allows the tissue to act as a first line of defense against inhaled microbes and foreign particles. The epithelial surface covering the tonsil is composed of ciliated pseudostratified columnar cells.
The tissue performs immune surveillance by sampling the antigens that pass over its surface. This exposure initiates an immune response within the specialized lymphoid follicles inside the tissue. The pharyngeal tonsil produces various antibodies, including Immunoglobulin A (IgA), Immunoglobulin G (IgG), and Immunoglobulin M (IgM). Secretory IgA provides mucosal immunity, offering local protection against respiratory pathogens.
Symptoms of Enlargement and Adenoidectomy
The pharyngeal tonsil can become enlarged, a condition called hypertrophy, often in response to chronic or recurrent infections. Due to its position high in the nasopharynx, a swollen adenoid can physically block the passage of air from the nose to the throat. This obstruction results in common symptoms such as persistent mouth breathing, chronic nasal congestion, and noisy breathing during the day.
Enlargement also causes significant issues during sleep, leading to loud snoring and, in severe cases, Obstructive Sleep Apnea (OSA), where breathing temporarily stops. Furthermore, the adenoid is located near the opening of the Eustachian tubes. Swelling can block these tubes, causing fluid buildup that often results in recurrent ear infections.
Adenoidectomy
The procedure to remove the pharyngeal tonsil is called an adenoidectomy. Surgery is considered when the tissue causes persistent breathing obstruction, leads to OSA, or contributes to chronic ear problems. Adenoid removal is a common procedure, often performed alongside a tonsillectomy for comprehensive management of upper airway obstruction.