This is a common question that I'm asked by patients. There is much mystery and misinformation about tonsils and adenoids; what they do; and whether they should or shouldn't be removed and what having the operation is like. This naturally gives rise to concern about what the right thing to do is. You can read more about tonsillectomy here, here and here or adenoidectomy here. 

A common anxiety is that the tonsils are useful, and removing them will somehow harm the immune system or body in some way. This is an entirely understandable concern - we have tonsils and adenoids, so they must serve some kind of purpose? 

Yes, that is certainly true. Tonsils and adenoids are made of lymphoid tissue and play a role in the development of the immune system and fighting infections. However, they only really play a role in the development of the immune system in the first year or two of life.  This is certainly a relevant point, however, this benefit needs to be weighed against the harm that tonsils and adenoids sometimes cause in children under the age of two.

After the age of two, there are no adverse effects on the immune system from tonsil removal. The average person has a couple of hundred lymph glands in the head and neck region, and the lining of the mouth and throat is peppered with lymphoid tissue, so there is more than enough surplus lymphoid tissue to fight infections.
 

So when should tonsils or adenoids be removed? 

Sometimes the answer is obvious - if you're having severe tonsillitis every month or your snoring is so bad that you can't breathe properly a night, then the decision may be an easy one. However, in many cases it isn't quite so clear. As a consequence, guidelines have been written, and research performed, to help patients and doctors decide whether tonsils or adenoids should be removed or not. It's important to remember that guidelines are just that, guidelines, and not rules. There may be situations, such as with multiple antibiotic allergies or other health problems, that may make tonsillectomy or adenoidectomy appropriate, even if criteria are not perfectly met. Conversely, if a patient has a bleeding disorder that cannot be controlled or conditions that make a general anaesthetic hazardous, then further observation and medical management rather than surgery may be appropriate.  

Tonsil and adenoid problems can be grouped into obstructive or infective problems, which I will discuss as separate groups. 

Infective Problems

Recurrent Tonsillitis: In the UK, the most commonly followed guidance is that written by the Scottish Intercollegiate Guidelines Network (SIGN), which is broadly similar to the guidance in the United States. In summary, these guidelines recommend tonsillectomy may be an appropriate treatment if the sore throats due to tonsillitis are severe and occur:

• Seven times in the previous year, if you have only had tonsillitis for one year. 
• Five times a year if you have had tonsillitis for two years. 
• Three times a year if you have had tonsillitis for three or more years. 

However, this does not mean that the tonsils should be removed. An acceptable alternative may be to continue monitoring the situation, with further courses of antibiotics being used to treat infections as they occur. Most people will 'grow out' of tonsillitis at some stage, the problem is not knowing when that is going to happen. 

Peritonsillar abscess ("Quinsy"): This is an unusual condition where a collection of pus ( an "abscess") forms next to the tonsil. If it occurs on one occasion, then tonsillectomy is usually not required, unless there is a background history of recurrent tonsillitis or blockage of the airway. If you have had two or more quinsies, then it is likely that you will have further quinsies, and tonsillectomy should be considered as a treatment. 

Tonsillar asymmetry: Occasionally one tonsil can be bigger than the other. In the vast majority of cases, this is due to previous infection, or slight differences in the anatomy of the tonsil bed on each side. Tumours or cancers of the tonsil are very rare. If there is any question or concern as to why one tonsil is larger than the other, it can be removed and sent for analysis. 

Recurrent (middle) ear infections ("recurrent acute otitis media"): These infections commonly cause symptoms of earache, raised temperature and sometimes discharge from the ear. Younger children and babies might pull their ears, or bang their head. The insertion of grommets can be very helpful if the infections are frequent. If the grommets fall out, and the problem continues, then removing the adenoids as well as putting in further grommets can help reduce the frequency of infections. 

Other conditions: There are a number of other situations where tonsillectomy might be appropriate, however good evidence from clinical trials is sometimes lacking. These conditions include:

• Recurrent tonsil stones ("tonsilloliths")
• Bad breath ("halitosis"), where other causes have been ruled out. 
• Chronic tonsillitis
• Chronic sinusitis in children. If medical treatments, such as topical steroid sprays in the nose, have not worked, then removing the adenoids is often helpful. 
• PFAPA ("Periodic Fever, aphthous stomatitis, pharyngitis and cervical adenitis") syndrome. This is an unusual condition, that as the name suggests, causes recurrent problems with fever, mouth ulcers, sore throats, and enlarged glands in the neck. It usually settles of its own accord, although occasionally removing the tonsils is appropriate. 

Obstructive Problems

Sometimes tonsils and adenoids can cause problems by virtue of their size. Depending on the circumstances, removal of the tonsils and adenoids can sometimes be helpful. 

Snoring with obstructive sleep apnoea (OSA): Snoring is the noise generated by obstructed airflow through the upper airways whilst asleep. Sometimes, the obstruction can be temporarily complete, that is to say for a short time breathing stops. This caused obstructive sleep apnoea, or "OSA". If this is severe, and the tonsils and adenoids are enlarged, then in most cases, removal of the adenoids and tonsils is advisable. In moderate or mild cases, it is often advisable to remove the tonsils and adenoids if the problem persists, although sometimes a further period of observation may be appropriate, as in many cases, children will grow out of this problem. 

Nasal obstruction: Sometimes in children, and much less commonly in adults, enlarged adenoids can cause a blocked nose. They can also give rise to a change in the quality of the voice, so it sounds as if you have a blocked nose when you speak (this is known as 'hyponasal speech'), and can sometimes affect the sense of smell. Removing the adenoids can be very helpful in relieving such symptoms. However, it is important that other causes of a blocked nose, such as allergic problems, a bend in the middle partition of the nose or chronic sinus infections are also identified and treated if present.

Less common obstructive problems where adenoidectomy or tonsillectomy may be helpful, although there is not good research evidence to support it include:
Swallowing problems ("dysphagia") caused by very large tonsils
Change in voice quality due to large tonsils or adenoids    

When should tonsils and adenoids not be removed? 

Sometimes removing the tonsils or adenoids can be especially risky, or likely to cause more problems than it solves. In these cases, it is often a good idea to avoid surgery. Such situations include:
A severe bleeding disorder: as with most operations, there is a (small) risk of bleeding when removing the tonsils or adenoids. If your body isn't able to clot properly, this can be a serious problem and surgery may be best avoided. 
Developmental problems of the palate or upper airway, such as cleft palate. In these conditions, the tonsils can play an important part in the swallowing mechanism. If the tonsils, and particularly the adenoids are removed, there is a higher risk of developing nasal regurgitation (food and especially drink, entering the nose when swallowing) and a type of nasal speech ('hypernasal' speech, collectively known as 'velopharyngeal incompetence'. Sometimes surgery is best avoided or modified to minimise this risk.
Neurological or muscular problems of the throat: operating in this situation also carries the risk of velopharyngeal incompetence (see above).
Active infection: If the tonsils are actively infected, the risk of bleeding at the time of, or after surgery is increased. In most cases, it is advisable for surgery to be postponed for two to three weeks after an episode of tonsillitis. 

What questions should I ask my surgeon?

As with any procedure, there are several factors that need to be considered:

• What does surgery involve, and what is the recovery like?
• What are the benefits and outcomes (ideally the surgeon's own outcomes) of doing the operation, or not doing the operation?
• What are the risks of the operation, but importantly, what are the risks of not having an operation? When talking about surgery, there is a natural tendency to focus solely on the risks of surgery, which will usually occur within a defined period of time. However, there are also risks of not doing surgery, such as problems developing with the heart and lungs with untreated obstructive sleep apnoea or infections from the tonsils spreading to other parts of the body. 
• Importantly, what are the alternatives to surgery?