Tonsils are small groups of lymphoid tissue that are located in the throat, back of the nose and tongue. The tonsils located in the back of the throat are referred to as palatine tonsils. The tonsils located at the back of the nose are referred to as adenoids, whereas the tonsils located at the back of the tongue are known as lingual tonsils.
The palatine tonsils can be seen at the back of the throat when an individual opens his or her mouth wide. However, the adenoids and lingual tonsils are hidden from direct view. The tonsils are an important part of the immune system. Their function is to trap potentially harmful microbes (bacteria and viruses) that enter the throat through the air we breathe.
Tonsillitis refers to an inflammation of the tonsils. Children between the age of five and fifteen years are most commonly affected by tonsillitis. In fact, inflammation of tonsils is one of the main causes of childhood surgery. A common reason for the inflammation of tonsils is sore throat caused by infections. Apart from the tonsils, other tissues of the throat are also inflamed in many cases of sore throat.
Such cases are referred to as tonsillopharyngitis. In tonsillopharyngitis, the inflammation of the palatine tonsils located on either side of the back of the throat can be observed directly. In addition to the palatine tonsils, tonsillopharyngitis may also involve the adenoids and lingual tonsils. However, inflammation in these tonsils cannot be observed directly.
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Why do the tonsils become inflamed and swollen?
When a tissue gets injured, infected or damaged, our bodies react through the process of inflammation. The main function of the tonsils is to filter out potentially harmful microbes that we breathe in during the process of respiration. The microbes that get trapped in the tonsils get destroyed by the immune cells in these tiny lymphoid organs.
In cases where the trapped microbes are not destroyed by the immune cells, the tonsils become infected and the process of inflammation begins. Inflammation of the tonsils in tonsillitis also affects other nearby tissues in the throat. The inflammatory response in tonsillitis involves secretion of chemical mediators of inflammation from the immune cells and the injured tissue.
These pro-inflammatory chemicals bring about a series of changes in the local tissue environment, leading to the hallmark signs and symptoms of inflammation. For example, these chemicals mediate the dilation of the blood vessels in the region, allowing fluid to seep out into the tissue of the tonsils. This causes swelling of the tonsils. The tonsils also appear red.
Pain is also present in the throat region. The pro-inflammatory chemicals also attract hordes of immune cells to the inflamed area. This is an attempt to limit the spread of infection and tissue damage. The inflammation and sore throat in tonsillitis usually clear up on their own within a few days or weeks. In some cases, however, untreated tonsillitis may become severe enough to cause serious complications.
Acute vs Chronic Tonsillitis
Depending on the duration of inflammation, cases of tonsillitis can be classified as acute or chronic.
Acute tonsillitis refers to a short-term inflammation of the tonsils. The condition appears suddenly, increases in intensity over a couple of days, and then subsides. Bouts of acute tonsillitis usually last from a few days to a couple of weeks.
Viral infections (such as common cold) are the most common triggers of acute tonsillitis. Unless the swelling of the tonsils causes significant obstruction to the critical processes of swallowing and breathing, surgery is not a treatment option.
Chronic tonsillitis is characterized by repeated episodes of acute inflammation. A persistent or continuous inflammation of the tonsils is rare. Chronic tonsillitis is defined in multiple ways:
- having 7 or more bouts of tonsillitis within a year,
- having 5 or more bouts of tonsillitis within a couple of years, or
- having four or more bouts of tonsillitis within a period of three years.
Due to the potential for serious complications in case of frequent bouts of tonsillitis, surgery is the preferred treatment option for chronic tonsillitis.
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Signs and Symptoms
The following are some of the typical signs and symptoms of tonsillitis.
Soreness or pain in the throat is one of the characteristic symptoms of tonsillitis. The pain from sore throat can spread to the ears. Swallowing also becomes a painful activity. Drinking hot beverages may worsen the pain. Affected children may stop feeding due to the pain and become very fussy.
Swelling of the affected tissue is a typical characteristic of inflammation. Tonsillitis also causes a swelling of the tonsils in the throat. The tonsils also become reddish in appearance. The swelling may become large enough to make swallowing a difficult and painful process. The voice may also become hoarse due to the swelling in the tissues of the throat. Surgery may be required in cases where the swelling significantly impairs feeding and breathing activities.
As with any infection, fever can occur with tonsillitis. However, a fever may not always be present with every tonsillitis case.
Infections and swollen tonsils in tonsillitis may also result in signs and symptoms such as snoring, runny nose, stiff neck, drooling, abdominal pain, headache and bad breath.
Causes of Tonsillitis
The most common cause of tonsillitis is infection with microbes, especially viruses and bacteria. Viral infections (such as common cold) account for the majority of cases of tonsillitis. Only about a third of the cases of tonsillitis are caused by bacterial infections. In some cases of tonsillitis, both viral and bacterial infections may be present simultaneously.
Examples of viruses that can cause tonsillitis include adenovirus, influenza virus, Herpes simplex virus, cytomegalovirus, rhinovirus, measles virus, Epstein-Barr virus and respiratory syncytial virus. Examples of bacteria that can cause tonsillitis include Streptococcus pneumoniae, Staphylococcus aureus, Group-A beta-hemolytic streptococcus, Chlamydia pneumoniae and Mycoplasma pneumoniae.
Diagnosis and Treatment
Tonsillitis can be diagnosed by physically examining the tonsils for the signs of inflammation. Presence of red swollen tonsils, enlarged lymph nodes, and fever can be easily detected during a simple physical examination. Throat swabs and blood tests to detect infection may be done, but are usually not required.
One must also differentiate between tonsillitis and other conditions that produce similar signs and symptoms. Examples of confounding conditions include epiglottitis, diphtheria, infectious mononucleosis, HIV infection, and head and neck cancers.
Most cases of acute tonsillitis do not require any medical treatment. Viral infections usually resolve on their own within a few days. Bacterial infections may require treatment with antibiotics. Inflammation can be managed through the use of over-the-counter drugs such as ibuprofen and acetaminophen.
In some severe cases of tonsillitis (such as those caused by infectious mononucleosis), corticosteroids may be used. Surgical removal of tonsils is the preferred treatment option in cases of chronic tonsillitis. Surgery may also be considered in some cases of acute tonsillitis that impair the swallowing and breathing processes significantly.