Basics
Description
- Suppurative complication of tonsillitis where infection spreads outside the tonsillar capsule between the palatine tonsil and pharyngeal muscles
- Most common deep infection of the head and neck (incidence of 30/100,000 per year)
- In the US, 45,000 cases annually
- Occurs in all ages, more commonly in young adults (mean age 20 " 40 yr)
- Occurs most commonly Nov " Dec, April " May (coincides with highest incidence rates of streptococcal pharyngitis)
- Complications:
- Airway compromise (uncommon)
- Sepsis (uncommon)
- Recurrence (12 " 15%)
- Extension to lateral neck or mediastinum
- Spontaneous perforation and aspiration pneumonitis
- Jugular vein thrombosis (Lemierre syndrome)
- Poststreptococcal sequelae (glomerulonephritis, rheumatic fever)
- Hemorrhage from extension and erosion into carotid sheath
- Severe dehydration
- Intracranial extension (meningitis, cavernous sinus thrombosis, cerebral abscess)
- Dural sinus thrombosis
Etiology
- 2 theories explain the development of peritonsillar abscess (PTA):
- Direct bacterial invasion into deeper tissues in the patient with acute pharyngitis
- Acute obstruction and bacterial infection of small salivary glands (Weber glands) in the superior tonsil
- Smoking may be a risk factor
- Most common pathogens:
- Group-A Streptococcus
- Staphylococcal species, including methicillin-resistant Staphylococcus aureus (MRSA)
- Anaerobes (Prevotella, Peptostreptococcus, Fusobacterium)
- Polymicrobial
Diagnosis
Signs and Symptoms
History
- Sore throat
- Fever
- Voice change
- Odynophagia (difficulty swallowing)
- Drooling
- Headache
- Pain radiating to the ear
- Decreased PO intake
- Malaise
Physical Exam
- Fever
- Trismus
- "Hot potato " voice
- Erythematous tonsils/soft palate
- Inferior and medial displacement of superior pole of tonsil on affected side
- Uvular deviation away from affected side
- Halitosis
- Cervical lymphadenitis
- Tenderness on ipsilateral side of neck at the angle of the jaw
Essential Workup
- Evaluation for deep space infections beyond the PTA, either with additional imaging or physical exam that may require admission and surgery
- Evaluate and ensure airway patency: Look for stridor, tripod position, or inability to handle secretions
- Definitive management with either needle aspiration or incision and drainage (I&D), followed by a course of antibiotics
Diagnosis Tests & Interpretation
- Usually a clinical diagnosis made by visually examining oropharynx
- May be difficult with severe trismus
Lab
- Throat culture and monospot (20% incidence of mononucleosis with PTA)
- CBC and culture of the abscess contents may be useful in some cases
- Basic metabolic panel may be useful in patients with decreased oral intake and clinical signs of dehydration
Imaging
- Bedside intraoral US:
- Using the high-frequency intracavitary US transducer with a lubricated latex cover can aid in identification and localization of the abscess
- A cooperative patient can place the transducer at the point of maximum tenderness
- Transcutaneous cervical ultrasound is an option when the patient has too much trismus to use an intracavitary probe
- Soft-tissue lateral neck:
- If suspicion for epiglottitis or retropharyngeal abscess exists
- Chest radiograph:
- With severe respiratory symptoms or draining abscess
- CT scan of neck:
- If suspicion exists for other deep space infection of the neck, CT may be indicated
- CT also may be indicated if unable to obtain a good exam secondary to trismus
- CT may locate abscess pocket after failed needle aspiration
- MRI may be useful to evaluate for complications of deep space infections (internal jugular vein thrombosis or erosion into the carotid sheath)
Diagnostic Procedures/Surgery
- Needle aspiration is diagnostic and often curative
- Bedside I&D
Differential Diagnosis
- Peritonsillar cellulitis
- Epiglottitis
- Retropharyngeal abscess
- Peripharyngeal abscess
- Tracheitis
- Meningitis
- Retropharyngeal hemorrhage
- Cervical osteomyelitis
- Cervical adenitis
- Epidural abscess
- Infectious mononucleosis
- Internal carotid artery aneurysm
- Lymphoma
- Foreign body
- Other deep space infections of the neck
Treatment
Pre-Hospital
Rarely associated with airway emergencies, but diagnosis is likely to be uncertain in transport, so suction and intubation equipment should be at the bedside:
- Pulse oximetry, supplemental oxygen
- Cardiac monitor
- IV access
- PTA occurs in children (<18 yr) in 25 " 30% of reported cases (14 cases per 100,000 population)
- Young children may need sedation or general anesthesia if I&D or aspiration of the abscess is attempted
- Obtain soft-tissue lateral neck radiograph before oral exam in young children with symptoms of upper airway obstruction
Initial Stabilization/Therapy
- Same as for pre-hospital
- Airway management may be necessary
- Equipment for intubation and cricothyroidotomy should be available
Ed Treatment/Procedures
- Antibiotics should be administered
- IV fluid should be given for dehydration
- Pain control is important
- A single dose of steroids may improve symptoms
- Adequate anesthesia prior to aspiration or I&D procedures is important:
- Benzocaine spray
- Lidocaine, 1% with 1:100,000 epinephrine
- No clear benefit for one drainage technique over another:
- Needle drainage:
- Successful 87 " 94%
- Should be performed by a person experienced in drainage procedure and adept at advanced airway techniques
- Less painful, less invasive than I&D
- The internal carotid artery lies ’ Ό2.5 cm posterolaterally to the tonsil; sheathing the aspiration needle to prevent introduction of the needle to <0.5 cm is prudent
- The superior pole of the tonsil is the most common place for maximal fluctuance (followed by the middle pole and then the inferior pole)
- Repeat aspiration is necessary in 10%
- I&D:
- Successful 90 " 92%
- An 11- or 15-blade scalpel is used to make stab incision to area of fluctuance
- Guard scalpel with trimmed plastic sheath leaving 1 cm of blade exposed
- Avoid >0.5 cm depth
- Medial and superior incisions are safer from the standpoint of potential injury to the carotid artery
- Incision typically made superior to tonsil in area of soft palate. Incision in the tonsil itself causes excessive bleeding and may miss the abscess, which is located in the peritonsillar soft tissue of the soft palate.
- Suction should be ready to remove purulent drainage and blood
- Packing is not used
- Tonsillectomy (indications in children):
- Upper airway obstruction
- Previous episodes of severe recurrent pharyngitis or PTA
- Failure of abscess resolution with other drainage techniques
- Can be performed immediately or after resolution of acute infection
Medication
- Length of antibiotic treatment should be 14 days (<10 day treatment course may be associated with recurrence)
- Adjunct with steroids can improve symptoms
Intravenous Antibiotics
- Ampicillin/Sulbactam (Unasyn), 3 gm q6h
- Penicillin G, 10 million U q6h + Metronidazole (Flagyl), 500 mg q6h
- If allergic to Penicillin, Clindamycin, 900 mg q8h
Oral Antibiotics
- Amoxicillin/Clavulanic acid (Augmentin), 875 mg BID
- Penicillin VK, 500 mg q6h + Metronidazole (Flagyl), 500 mg q6h
- Clindamycin, 600 mg BID or 300 mg q6h
Steroids
- Dexamethasone, 10 mg IV/IM/PO single dose
- Pediatrics: 0.6 mg/kg; not to exceed 10 mg
- Methylprednisolone, 2 mg/kg; not to exceed 250 mg
Follow-Up
Disposition
Admission Criteria
- Airway compromise
- Sepsis
- Altered mental status
- Dehydration and inadequate PO intake
- Extension of infection beyond the PTA (i.e., deep space neck infections)
Discharge Criteria
- Most patients with PTA can be discharged home on oral antibiotics after abscess drainage
- Must be able to tolerate sufficient oral intake and antibiotics
Issues for Referral
- Referral to an otolaryngologist or surgeon should be provided
- Tonsillectomy is recommended 6 " 8 wk following treatment of the abscess
Followup Recommendations
Close follow-up recommended in 24 " 48 hr:
- Treatment failures and recurrences are relatively common
Pearls and Pitfalls
- Failure to secure the airway early in a severe infection
- Failure to recognize a more advanced, deep space infection of the neck
- Knowing the anatomy before performing needle aspiration or bedside I&D
- Bedside US is a useful adjunct in differentiating and identifying a PTA vs. peritonsillar cellulitis
Additional Reading
- Araujo Filho BC, Sakae FA, Sennes LU, et al. Intraoral and transcutaneous cervical ultrasound in the differential diagnosis of peritonsillar cellulitis and abscesses. Braz J Otorhinolaryngol. 2006;72:377 " 381.
- Brook I. Pediatric Peritonsillar Abscess, Medscape. Retrieved Dec 13, 2012 from http://emedicine.medscape.com/article/970260-overview.
- Costantino TG, Satz WA, Dehnkamp W, et al. Randomized trial comparing intraoral ultrasound to landmark-based needle aspiration in patients with suspected peritonsillar abscess. Acad Emerg Med. 2012;19:626 " 631.
- Marx JA, Hockberger RS, Walls RM, et al. Rosens Emergency Medicine: Concepts and Clinical Practice. 7th ed. St. Louis, MO: Mosby; 2009.
- Millar KR, Johnson DW, Drummond D, et al. Suspected peritonsillar abscess in children. Pediatric Emerg Care. 2007;23:431 " 438.
- Powell J, Wilson JA. An evidence-based review of peritonsillar abscess. Clin Otolaryngol. 2012;37:136 " 145.
- Tan A. Peritonsillar Abscess in Emergency Medicine, Medscape. Retrieved Dec 13, 2012 from http://emedicine.medscape.com/article/764188-overview.
- Wald, Ellen, MD (2012). Peritonsillar cellulitis and abscess. UpToDate. Retrieved January, 2013 from http://www.uptodate.com/contents/peritonsillar-cellulitis-and-abscess.
Media Element
- Epiglottitis
- Retropharyngeal Abscess
Codes
ICD9
475 Peritonsillar abscess
ICD10
J36 Peritonsillar abscess
SNOMED
- 15033003 Peritonsillar abscess (disorder)