Author:
Tyler J.Berliner
Maria E.Moreira
Description
- Deep tissue infection of the retropharyngeal space:
- Potential space bound anteriorly by buccopharyngeal fascia, posteriorly by alar fascia, superiorly by skull base, inferiorly by fusion of fascial layers at T2
- Space fused by raphe at midline with chains of lymph nodes extending down each side
- Alar fascia is poor barrier and allows retropharyngeal infections to spread into “danger” space and posterior mediastinum
- Primarily a disease of children, but increasing frequency in adults:
- Peak incidence at 3-5 yr when retropharyngeal nodes most prominent
- Prognosis is good when promptly diagnosed and aggressively managed with IV antibiotics and /or surgical drainage
- Complications due to mass effect, rupture, or spread are the major source of morbidity and include:
- Airway compromise (most common)
- Aspiration pneumonia due to rupture
- Sepsis
- Spontaneous perforation
- Necrotizing soft tissue infection
- Mediastinitis
- Thrombosis of the internal jugular vein
- Jugular vein suppurative thrombophlebitis (Lemierre syndrome)
- Erosion into carotid artery (primarily adults)
- Atlantoaxial dislocation from erosion of ligaments
- Cranial nerve palsies (typically IX-XII)
- Epidural abscess
- Recurrent abscess formation (1-5%)
Etiology
- Causes:
- Most often arises from infection of nasopharynx, paranasal sinuses, or middle ear
- Infection then spreads to lymph nodes between posterior pharyngeal wall and alar fascia
- Trauma, foreign bodies, and iatrogenic introduction of infection from instrumentation also common cause, especially in adults
- Diabetes and other immunosuppressed states may predispose to this infection
- Bacteriology: Predominately polymicrobial with anaerobes and aerobes
- Most common organisms are:
- Streptococcus pyogenes and Streptococcus viridans
- Staphylococcus aureus (including MRSA)
- Respiratory anaerobes (including Prevotella, Fusobacterium, and Veillonella)
- Less common organisms are:
- Haemophilus species
- Acid-fast bacilli
- Klebsiella pneumoniae
- Escherichia coli
- Eikenella corrodens
- Mycobacterium tuberculosis
- Aspergillus and Cand ida species
Signs and Symptoms
May differ between adults and children
History
- Most common:
- Sore throat
- Neck pain/stiffness
- Odynophagia
- Dysphagia
- Fever
- Additional presenting symptoms:
- Stridor
- Dyspnea
- Muffled voice
- Trismus
Pediatric Considerations |
Young children may present with only:- Poor oral intake
- Lethargy or irritability
- Cough
|
Physical Exam
- Adults:
- Posterior pharyngeal edema
- Nuchal rigidity
- Cervical adenopathy
- Fever (67%)
- Drooling
- Stridor
- Dysphonia (cri du canard)
- Tracheal “rock” sign: Tenderness on moving the larynx and trachea side to side
- Children and infants:
- Cervical adenopathy
- Fever
- Neck stiffness with extension most frequently limited
- Retropharyngeal bulge
- Trismus
- Torticollis
- Drooling
- Agitation
- Respiratory distress
Essential Workup
Rapid assessment of airway and respiratory status:
- Normal exam does not rule out diagnosis
- No lab tests make the diagnosis
- When suspicious, obtain lateral neck x-ray or CT of neck with IV contrast
Diagnostic Tests & Interpretation
Lab
- CBC (WBC >12,000 in 91% of children):
- Blood cultures (both aerobic and anaerobic)
- Throat cultures
Imaging
- Portable films appropriate if concern for airway compromise
- Lateral neck radiographs:
- Film taken in inspiration with neck slightly extended
- May not get good exposure of soft tissue if cannot adequately extend neck due to pain or difficulty cooperating in young age
- Increased suspicion if:
- Retropharyngeal space anterior to C2 >7 mm or 2× the diameter of the vertebral body (sensitivity 90%)
- Space anterior to C6 >14 mm in preschool children or 22 mm in adults
- Loss of normal cervical lordosis
- Chest radiograph:
- Indicated if abscess identified to assess for inferior spread of infection and /or aspiration of ruptured abscess contents
- Mediastinal widening is suggestive of mediastinitis and possible rupture
- US of neck:
- Low sensitivity
- Not recommended
- CT of neck with IV contrast:
- Now preferred imaging modality
- Obtain when x-rays nondiagnostic or to determine exact size and location of abscess noted on x-ray
- Abscess appears as hypodense lesion with peripheral ring enhancement in retropharyngeal space
- Sensitivity: 64-100%
- Specificity: 45-88%
- Can aid in operative planning, revealing extent of invasion into retro/parapharyngeal spaces
- Unclear if it reliably can distinguish abscess from cellulitis and lymphadenitis
- Due to radiation exposure and need for sedation, CT should only be obtained in young children if x-rays are nondiagnostic
- MRI:
- More sensitive than CT
- Also useful for imaging vascular lesions such as jugular thrombophlebitis
Diagnostic Procedures/Surgery
- Surgical drainage/needle aspiration should be performed in OR:
- Presence of pus is gold stand ard for making diagnosis
- Abscess should be completely evacuated
- Pus should be sent for Gram stain and culture
- No role for nasopharyngolaryngoscopy
Differential Diagnosis
- Tonsillopharyngitis
- Epiglottitis
- Peritonsillar abscess
- Suppurative parotitis
- Submand ibular space infection (Ludwig angina)
- Acute calcific tendonitis of Longus colli muscle
- Croup
- Foreign body
- Tracheitis
- Meningitis
- Retropharyngeal hemorrhage
- Dystonic reactions
- Cervical osteomyelitis
- Dental infections
- Mononucleosis
- Epidural abscess
- Other deep space infection of the neck
Prehospital
- Keep child in position of comfort:
- Forcing child to sit up or flex neck may occlude airway
- Pulse oximetry, cardiac monitor
- Supplemental oxygen
- Adequate hydration
- Suction, endotracheal tube, cricothyrotomy (or needle cricothyrotomy for age <10-12) equipment ready for potential emergent intubation
- Airway control will be required for:
- Airway compromise
- Prior to long transport
Initial Stabilization/Therapy
- Assess and control airway
- Provide supplemental oxygen
- IV access:
- Avoid if signs of airway compromise
ED Treatment/Procedures
- Early endotracheal intubation or cricothyrotomy for patients with respiratory distress or impending obstruction:
- Caution must be used with induction, as sedation medications may lead to relaxation of airway muscles causing complete obstruction
- Rescue airway equipment such as a laryngeal mask airway available
- Pharyngeal swelling may make intubation difficult
- Cricothyrotomy may be required if upper airway is obstructed
- Surgical consultation (ear/nose/throat if available)
- Early administration of IV antibiotics
Medication
Empiric IV antibiotic therapy to cover group A streptococci, S. aureus (including MRSA), and respiratory anaerobes:
- Antibiotic tailored to local preferences and susceptibilities
- Coverage is narrowed when culture results and sensitivities return
- Use of corticosteroids is controversial and recommended only after consultation with ear/nose/throat
- Immunocompromised, diabetics, IV drug users, institutionalized patients, and young children (<2 yr) are at high risk for MRSA
First Line
Oral or odontogenic source:
- Ampicillin-sulbactam: 3 g IV q6h (peds: 50 mg/kg/dose)
- Penicillin G 2-4 million units IV q4-6h + metronidazole 500 mg IV q6-8h
- Clindamycin: 600-900 mg (peds: 15 mg/kg) IV q8h (max 4.8 g/d)
Rhinogenic or otogenic source:
- Ampicillin-sulbactam: 3g IV q6h
- Ceftriaxone 1 g IV q24h + metronidazole 500 mg IV q6-8h
- Doxycycline: 100 mg IV b.i.d
If Eikenella suspected (associated with some odontogenic infections):
- Moxifloxacin: 400 mg per day
Second Line
If patient is at high risk for MRSA, add:
- Vancomycin: 15-20 mg/kg (peds: 40-60 mg/kg/24 hr IV q6-8h) IV q12h
- Linezolid: 600 mg (peds: 0-11 yr: 30 mg/kg/24 hr q8h; >12 yr: adult dose) IV/PO q12h
If patient is immunocompromised:
- Cefepime 2g IV b.i.d + metronidazole 500 mg IV q6-8h
- Imipenem: 500 mg IV q6h
- Meropenem: 1 g IV q8h
- Piperacillin-tazobactam: 4.5 g IV q6h
Disposition
Admission Criteria
- All patients with retropharyngeal abscess should be admitted to the hospital for IV antibiotics and possible surgical drainage
- Criteria for surgical drainage:
- Airway compromise or other life-threatening complications
- Large (>2 cm hypodense area on CT)
- Failure to respond to parenteral antibiotic therapy
- ICU admission for patients with:
- Airway compromise
- Sepsis
- Altered mental status
- Hemodynamic instability
- Infants and toxic-appearing children
- Major comorbidities
Discharge Criteria
Patients with retropharyngeal abscesses should not be discharged
Issues for Referral
Transfer should be considered if facility does not have the ability to drain infection:
- Airway should be stabilized prior to transfer
See Also (Topic, Algorithm, Electronic Media Element)
ICD9
478.24 Retropharyngeal abscess
ICD10
J39.0 Retropharyngeal and parapharyngeal abscess
SNOMED