Peritonsillar abscess is the most common deep infection of the head and neck and usually a complication of acute tonsillitis. It always warrants immediate therapy.
The condition can also be managed in primary health care. Refer to an ENT clinic for treatment:
Tongue blade, long 18 Gauge needle and 10 ml or 20 ml syringe, No. 11 scalpel blade, angulated or haemostatic forceps
Suction equipment
I.v. rehydration kit if the patient is dehydrated
Procedure
If necessary the patient is administered i.v. fluids and analgesics before the procedure.
While the patient is placed in sitting upright position and keeps his/her mouth as open as possible, depress the tongue with tongue depressor. Hypopharynx and larynx are inspected with a mirror to exclude lower oedema and bulging of the tissues and possible airway obstruction.
The most prominent area of the mucous membrane overlying the abscess is sprayed with topical anaesthetic.
1-2 ml of local anaesthetic is infiltrated under the palatoglossal arch at the location of the abscess, first right under the mucous membrane and then deeper. Try to localize the abscess by aspirating from three locations (picture 1).
If the abcess is not sufficiently emptied by needle aspiration, a larger incision is needed. Under local anaesthesia make a 1-1.5 cm incision in the mucous membrane parallel to the palatal arch at the site with the largest bulge.
Dissect along the capsule of the tonsil with haemostatic or angulated forceps until the abscess cavity is found. Spread the forceps only when in the abscess cavity. You should find your way to the back of the tonsil around its edge and not get mixed up in the tonsillar tissue. Work in sagittal plane and avoid proceeding too far laterally (carotid artery).
Remove all pus with a rigid catheter for oral suction (metallic or plastic) and take a sample for bacterial culture if needed.
The patient should sit leaning forward and rinse the mouth with cool mouth wash until bleeding stops.
Give a sufficient dose of analgesics (e.g. ibuprofen 600 mg × 3 as necessary).
Antimicrobial therapy: Either oral or parenteral penicillin V according to the severity of the disease (1 million IU 3 times daily for 10 days). In a large share of abscesses, there are anaerobic bacteria involved, but there is no evidence on the benefit of the use of broader-spectrum antimicrobial drugs in an adult patient whose abscess has been initially drained. If the patient cannot take penicillin, either a cephalosporin or amoxicillin or, in the case of allergy, clindamycin may be used. If the abscess is not found through aspiration or incision, or if it is not adequately drained, metronidazole (400 mg 3 times daily for 7 days) may be added to the treatment.
Depending on the patient's work, sick leave is usually needed for a few days or a week.
The patient should come for a follow-up visit 1 to 2 days after the incision if symptoms persist. The abscess cavity is opened with angular forceps (local anaesthesia) and drained. If necessary, the procedure is repeated after 2 days.
Tonsillectomy
Peritonsillar abscess is an indication for tonsillectomy if the patient has had recurrent episodes of tonsillitis or the abscess recurs.
In children, tonsillectomy is usually performed immediately (in the "hot" phase).
References
Powell J, Wilson JA. An evidence-based review of peritonsillar abscess. Clin Otolaryngol 2012;37(2):136-45. [PubMed]
Khayr W, Taepke J. Management of peritonsillar abscess: needle aspiration versus incision and drainage versus tonsillectomy. Am J Ther 2005 Jul-Aug;12(4):344-50. [PubMed]
Shaul C, Koslowsky B, Rodriguez M et al. Is Needle Aspiration for Peritonsillar Abscess Still as Good as We Think? A Long-term Follow-up. Ann Otol Rhinol Laryngol 2015;124(4):299-304. [PubMed]
Wikstén JE, Pitkäranta A, Blomgren K. Metronidazole in conjunction with penicillin neither prevents recurrence nor enhances recovery from peritonsillar abscess when compared with penicillin alone: a prospective, double-blind, randomized, placebo-controlled trial. J Antimicrob Chemother 2016;71(6):1681-7. [PubMed]