TONSILS

 

·        Tonsils are collections of lymphoid tissue facing into the aerodigestive tract.

·        The set of lymphatic tissue known as Waldeyer's tonsillar ring includes the adenoid tonsil, two tubal tonsils, two palatine tonsils, and the lingual tonsil.

 

 

Structure

Tonsils in humans include:

Type	Epithelium	capsule	Crypts	Location
Adenoids (also termed "pharyngeal tonsils")	Ciliated pseudostratified columnar (respiratory epithelium)	Incompletely encapsulated	No crypts, but small folds	Roof of pharynx
Tubal tonsils	Ciliated pseudostratified columnar (respiratory epithelium)			Roof of pharynx
Palatine tonsils	Non-keratinized stratified squamous	Incompletely encapsulated	Long, branched	Sides of oropharynx between palatoglossal and palatopharyngeal arches
Lingual tonsils	Non-keratinized stratified squamous	Incompletely encapsulated	Long, branched	Behind terminal sulcus (tongue)

 

·        When used unqualified, the term most commonly refers specifically to the palatine tonsils, which are masses of lymphatic material situated at either side at the back of the human throat.

·        The palatine tonsils and the nasopharyngeal tonsil are lymphoepithelial tissues located near the oropharynx and nasopharynx (parts of the throat).

 

Palatine tonsil

·        The palatine tonsils are located at the back of the throat. One tonsil is located on the left side of the throat and the other is located on the right side.

·        The tonsils play a role in protecting the body against respiratory and gastrointestinal infections.

 

·        Each tonsil consists of a network of crypts (pits) that store cells used to fight infection. The tonsils contain B cells, a type of white blood cell that fights infections. They also produce antibodies against polio, streptococcal pneumonia, influenza, and numerous other infections. Antibodies are proteins that help the body identify and attack harmful invaders.

 

·        The tonsils also contain several types of T cells, which are white blood cells that destroy cells infected with viruses and help the body build immunity to infectious organisms.

 

 

·        Tonsillitis occurs when bacterial or viral organisms cause inflammation of the tonsillar tissue. This results in fever, difficulty swallowing, sore throat, ear pain, loss of voice, and throat tenderness.

 

Development

·        Tonsils tend to reach their largest size near puberty, and they gradually undergo atrophy thereafter. However, they are largest relative to the diameter of the throat in young children.

Function

·        These immunocompetent tissues are the immune system's first line of defense against ingested or inhaled foreign pathogens.

·        Tonsils have on their surface specialized antigen capture cells called M cells that allow for the uptake of antigens produced by pathogens.

·        These M cells then alert the underlying B cells and T cells in the tonsil that a pathogen is present and an immune response is stimulated.

·        B cells are activated and proliferate in areas called germinal centres in the tonsil.

·        These germinal centres are places where B memory cells are created and secretory antibody (IgA) is produced.

 

·        Recent studies have provided evidence that the tonsils produce T lymphocytes, also known as T-cells, in a manner similar to, but different from, the way the thymus does.

 

Signs and symptoms

Common signs and symptoms include:

·        sore throat

·        red, swollen tonsils

·        pain when swallowing

·        high temperature (fever)

·        headache

·        tiredness

·        chills

·        a general sense of feeling unwell (malaise)

·        white pus-filled spots on the tonsils

·        swollen lymph nodes (glands) in the neck

·        pain in the ears or neck

·        weight loss

·        difficulty ingesting and swallowing meal/liquid intake

·        difficulty sleeping

 

Less common symptoms include:

·        nausea

·        fatigue

·        stomach ache

·        vomiting

·        furry tongue

·        bad breath (halitosis)

·        voice changes

·        difficulty opening the mouth (trismus)

·        loss of appetite

·        Anxiety/fear of choking

·        In cases of acute tonsillitis, the surface of the tonsil may be bright red and with visible white areas or streaks of pus.

 

·        Tonsilloliths occur in up to 10% of the population frequently due to episodes of tonsillitis

 

·        Tonsils can become enlarged (Aden tonsillar hyperplasia) or inflamed (tonsillitis).

·        This may be of clinical significance if they obstruct the airway or interfere with swallowing, or in patients with frequent recurrent tonsillitis.

 

·        In older patients, asymmetric tonsils (also known as asymmetric tonsil hypertrophy) may be an indicator of virally infected tonsils, or tumors such as lymphoma or squamous cell carcinoma.

 

·        Tonsillitis is a disorder in which the tonsils are inflamed (sore and swollen).

 

·        A tonsillolith is material that accumulates on the tonsil. They can range up to the size of a peppercorn and are white/cream in color.

·        The main substance is mostly calcium, but they have a strong unpleasant odor because of hydrogen sulfide and methyl mercaptan and other chemicals.

 

·        Tonsil enlargement can affect speech, making it hyper nasal and giving it the sound of velopharyngeal incompetence (when space in the mouth is not fully separated from the nose's air space).

 

·         Tonsil size may have a more significant impact on upper airway obstruction for obese children than for those of average weight.

 

·        As mucosal lymphatic tissue of the aero digestive tract, the tonsils are viewed in some classifications as belonging to both the gut-associated lymphoid tissue (GALT) and the mucosa-associated lymphoid tissue (MALT).

 

·        Other viewpoints treat them (and the spleen and thymus) as large lymphatic organs contradistinguished from the smaller tissue loci of GALT and MALT.

 

 

 

Diagnostic tests:

·        Throat swab.

·        The diagnosis of group A beta-hemolytic streptococcus (GABHS) tonsillitis can be confirmed by culture of samples obtained by swabbing both tonsillar surfaces and the posterior pharyngeal wall and plating them on sheep blood agar medium

·        . A single throat culture has a sensitivity of 90–95% for the detection of GABHS (which means that GABHS is actually present 5–10% of the time culture suggests that it is absent).

·        Bacterial culture may need to be performed in cases of a negative rapid streptococcal test.

·        Increased values of secreted phospholipase A2 and altered fatty acid metabolism in patients with tonsillitis may have diagnostic utility.

Management:

·        Warm salt water gargle or warm liquids.

Complications:

·        Complications may rarely include blocked airways due to inflammation, and pharyngitis due to the spread of infection.

 

·        An abscess may develop lateral to the tonsil during an infection, typically several days after the onset of tonsillitis. This is termed a peritonsillar abscess (or quinsy).

 

·        Rarely, the infection may spread beyond the tonsil resulting in inflammation and infection of the internal jugular vein giving rise to a spreading septicaemia infection (Lemierre's syndrome).

 

·        In strep throat, very rarely diseases like rheumatic fever or glomerulonephritis can occur. These complications are extremely rare in developed nations but remain a significant problem in poorer nations.

·        Tonsillitis associated with strep throat, if untreated, is hypothesized to lead to pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS).