All of the following are indications for tonsillectomy except-a) Foreign body in tonsilsb) Unilateral enlargement of tonsils with suspected malignancyc) Keratin tonsild) Recurrent quinsy
Tonsillectomy

Tonsillectomy, as the name suggests, is the surgical procedure to remove the tonsils.
Often, tonsillectomy is done at the same time as adenoidectomy.

Indications

Indications are divided into :-

A) Absolute
1.   Recurrent infections of throat. This is the most common indication. Recurrent infections are further defined
as

Seven or more episodes in one year, or
Five episodes per year for 2 years, or
Three episodes per year for 3 years, or
Two weeks or more of lost school or work in one year.

2. Peritonsillar abscess. In children. tonsillectomy is done 4-6 weeks after abscess has been treated. In adults, second attack of peritonsillar abscess forms the absolute indication.
3.   Tonsillitis causing febrile seizures.
4.   Hypertrophy of tonsils causing

Airway obstruction (sleep apnoea)
Difficulty in deglutition
Interference with speech.

5.   Suspicion of malignancy. A unilaterally enlarged tonsil may be a lymphoma in children and an epidermoid
carcinoma in adults. An excisional biopsy is done.
B) Relative 

Diphtheria carriers, who do not respond to antibiotics
Streptococcal carriers, who may be the source of infection to others.
Chronic tonsillitis with bad taste or halitosis which is unresponsive to medical treatment.
Recurrent streptococcal tonsillitis in a patient with valvular heart disease.

C) As a part of Another Operation

Palatopharyngoplaty which is done for sleep apnoea syndrome.
Glossopharyngeal neurectomy. Tonsil is removed first and then IX nerve is severed in the bed of tonsil.
Removal of styloid process.

About option 'a'

Foreign body in tonsils is very rare, and the treatment is removal of foreign body. I could not find any information about keratin tonsil.
ac
bc
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b