Pediatric Retropharyngeal Abscess 

Updated: Mar 25, 2019
Author: Vijay A Patel, MD; Chief Editor: Ravindhra G Elluru, MD, PhD 

Overview

Practice Essentials

Retropharyngeal abscess (RPA) is a deep neck space infection that can pose an immediate life-threatening emergency, with potential for airway compromise and other catastrophic complications.

Signs and symptoms

Patients with an RPA are likely to experience a constellation of symptoms, including fever, malaise, decreased appetite, irritability, sore throat, dysphagia, odynophagia, trismus, or torticollis. The overall presentation can be insidious, even stemming from a recent upper respiratory tract infection that has not completely resolved. In view of the clinical ambiguity, especially early in the infectious course, it is important to maintain a high index of suspicion.

Physical examination findings that are commonly found in children with RPA include the following:

  • Fever
  • Toxic appearance
  • Tender lymphadenopathy (often unilateral)
  • Decreased or painful range of motion of the neck or jaw
  • Dysphonia ("hot potato" voice) 

Stridor and drooling are indications of possible airway compromise, which necessitate emergency intervention with respect to airway stabilization. Finally, bulging of the posterior pharyngeal wall is common and is usually asymmetric. 

The clinical course may appear unremarkable in the early stages, resembling that of uncomplicated pharyngitis. However, later stages may result in dysphagia, dysphonia, or respiratory compromise. If labored breathing or posturing is present, it is imperative to rule out airway obstruction and secure the airway if deemed clinically necessary. However, blind endotracheal intubation should be avoided because of the possibility of rupturing the abscess and causing either further airway obstruction or aspiration pneumonia. 

Diagnosis

Upon initial evaluation, patients in whom there is concern about a possible RPA should be evaluated and stabilized by both pediatric hospitalists and pediatric otolaryngologists. Blood tests typically obtained include the following:

  • Blood culture
  • Complete blood count with differential
  • Inflammatory markers

Imaging studies that may be considered include the following:

  • Lateral neck radiograph
  • Contrast-enhanced computed tomography (CT) scan of the neck

Radiography has a lower sensitivity and often precedes CT. CT is the modality of choice for identifying the abscess or determining its location.

Management

Treatment with intravenous broad-spectrum antibiotics should also be promptly initiated, typically including a penicillin plus an antipenicillinase (eg, ampicillin-sulbactam). When possible methicillin-resistant Staphylococcus aureus infection is a concern, clindamycin or vancomycin should be considered for empiric therapy. Antibiotic planning should take into account that the microbiology of RPA is likely to include multiple pathogens, most likely gram-negative rods and anaerobes.

Sole medical management is typically employed in a monitored hospital setting for up to 72 hours to determine adequacy; surgical intervention via transoral or transcervical approaches is often indicated if the clinical picture does not improve. 

Background

Retropharyngeal abscess (RPA) is a deep neck space infection that can pose an immediate life-threatening emergency, with potential for airway compromise and other catastrophic complications.[1]

For an optimal understanding of deep-space infections, a strong knowledge of head and neck anatomy with respect to the fascial planes is necessary. Superficial and deep layers of the cervical fascia are found within the neck. Although this fascia is typically adherent to adjacent structures, potential spaces can be created when an infection intercalates between fascial layers and creates a real space, with rapid spread of infectious inflammation and purulence between fascial planes.

The retropharyngeal space is located immediately posterior to the pharynx (nasopharynx, oropharynx, and hypopharynx), larynx, and trachea. The visceral (buccopharyngeal) fascia, which surrounds the pharynx, trachea, esophagus, and thyroid, forms the anterior border of this space. Bounded posteriorly by the alar fascia, the retropharyngeal space is bounded laterally by the carotid sheaths and parapharyngeal spaces. It extends superiorly to the skull base and inferiorly to the mediastinum at the level of the tracheal bifurcation (see image below).

Schematic of neck deep space anatomy, as illustrat Schematic of neck deep space anatomy, as illustrated in lateral and cross-sectional views. Fascial planes (see color key) surround potential spaces. Anteriorly, retropharyngeal space is bounded by buccopharyngeal fascia, which invests pharynx, trachea, esophagus, and thyroid; posteriorly by alar fascia; and laterally by carotid sheaths and parapharyngeal spaces. Retropharyngeal space extends from skull base to mediastinum at level of tracheal bifurcation. Note danger space located between alar fascia and prevertebral fascia.

Two other potential spaces (the danger space and the prevertebral space) are located in close proximity to the retropharyngeal space. The danger space is formed anteriorly by the alar fascia and posteriorly by the prevertebral fascia. The prevertebral space is bounded anteriorly by the prevertebral fascia and posteriorly by the longus colli spinal muscles.

The danger space extends down the mediastinum to the level of the diaphragm, whereas the prevertebral space continues to the insertion of the psoas muscles. These anatomic relations can allow infection of the retropharyngeal space to spread to the mediastinum, leading to potentially fatal mediastinitis.

Pathophysiology

The retropharyngeal space can become infected in one of the following two ways:

  • Infectious spread from a contiguous area
  • Infection directly inoculated from penetrating trauma

The "classic" RPA is observed in pediatric patients occurs when an upper respiratory tract infection (URI) spreads to retropharyngeal lymph nodes, which form chains in the retropharyngeal space on either side of the superior constrictor muscle. Degeneration or suppuration of these nodes leads to abscess formation.

Of specific interest is the group of lateral retropharyngeal nodes at the skull base that bears the name of the French anatomist Henri Rouvière. The nodes of Rouvière typically are not of great clinical interest, but as the primary lymphatic drainage of the nasopharynx, they can become significant in cases of nasopharyngeal cancer. They are also pertinent to the discussion of RPA, in that they can suppurate and lead to abscess formation.

In children, RPA is usually caused by an infection which spreads to the retropharyngeal lymph nodes, with subsequent cellulitis and abscess formation. Fibrosis and atrophy start in these nodes at approximately 4 years of age; by 6 years of age, the retropharyngeal nodes typically regress. In older patients, infection of the retropharyngeal space usually occurs from penetrating trauma or direct spread from an adjacent space.

Complications of RPA arise from mass effect, abscess rupture, or infectious spread. The most urgent complication is RPA expansion against the pharynx or trachea, leading to airway compression. Abscess rupture can cause aspiration of purulent material, leading to asphyxiation or pneumonia. The spread of infection can also lead to inflammation and destruction of adjacent tissues.

Spread of infection to the mediastinum can result in mediastinitis, purulent pericarditis and tamponade, pyopneumothorax, pleuritis, empyema, or bronchial erosion. Lateral spread of infection can involve the carotid sheath and cause internal jugular vein thrombosis or carotid artery rupture. Posterior spread of infection can result in osteomyelitis and erosion of the spinal column, causing vertebral subluxation and spinal cord injury. Finally, RPA can evolve into necrotizing fasciitis, sepsis, and death.

Hence, accurate and prompt treatment of and intervention for presumed RPA are crucial to prevent significant untoward sequelae.

Etiology

Most retropharyngeal space infections arise from drainage to the retropharyngeal nodes from primary nasopharyngeal infections. The resulting lymphadenitis can lead to cellulitis, which can then suppurate and result in abscess formation. Possible predisposing infections can include the following:

Infectious sources (eg, osteomyelitis of the spine) also can spread directly anteriorly from the prevertebral space. Retropharyngeal infections can also spread from contiguous spaces, such as the parapharyngeal space, submandibular space, or prevertebral space.

Penetrating trauma can also be involved in retropharyngeal space infection via direct seeding. Accidental lacerations are not uncommon in children who run and fall down after they have placed a sharp object in their mouths. Parents may be unaware of these predisposing events, and thus the diagnosis can be even more elusive. Foreign bodies (fishbones) have also been implicated in penetrating trauma to the retropharyngeal space.

RPA can also be iatrogenic secondary to instrumentation of the upper respiratory tract. Iatrogenic causes of inoculation to this space include instrumentation with laryngoscopy, endotracheal intubation, surgery, endoscopy, feeding tube placement, and dental procedures.

Risk factors for RPA include low socioeconomic status, poor oral hygiene, and immune dysfunction (HIV, diabetes, or immunosuppression).

The infection is often polymicrobial, with gram-positive organisms and anaerobes predominating; however, gram-negative bacteria have also been isolated. The source of bacteria is usually the oropharyngeal flora, with the most common organisms being group A beta-hemolytic streptococci. Staphylococcus aureus is also fairly common. Abdel-Haq et al noted an increasing incidence of methicillin resistance in Staphylococcus isolates (24% of all cultures and 64% of Staphylococcus-positive cultures).[2]

The most common anaerobes are Bacteroides species. Other causative agents include Haemophilus parainfluenzae, Veillonella, Peptostreptococcus, Fusobacterium, and Eikenella species.

Mycobacterium tuberculosis, Bartonella henselae, and Coccidia should be suspected in patients who may be predisposed (immunosuppressed individuals or recent immigrants), especially if they are not responding to conventional therapies.

Finally, another consideration in the evaluation of these patients is the possibility of Lemierre syndrome (septic thrombophlebitis of the internal jugular vein secondary to RPA). This infection is classically associated with Fusobacterium necrophorum, an anaerobic gram-negative rod.[3] Surgical intervention, with adjunctive medical treatment that includes antibiotic therapy and anticoagulation, may be warranted in complicated RPA secondary to Lemierre syndrome.

Epidemiology

United States statistics

In an analysis of a large national database of pediatric admissions in the United States,[4]  Lander et al found 1321 cases of RPA in 2003. A large retrospective review of pediatric head and neck infections at the University of Mississippi Medical Center, published in 2006,[5] found that of the 1010 documented pediatric head and neck infections, 26 were RPA.

In a 2014 study, Novis et al used the Kids' Inpatient Database (KID) to evaluate the incidence, demographics, and outcomes of deep neck space infections in North American children between 2000-2009.[6] The incidence of pediatric RPA increased significantly, but there were no concurrent increases in combined deep neck space infections, peritonsillar abscesses, or parapharyngeal abscesses. Management of RPA changed over this period (decreased operative intervention and shorter average hospital stay).

International statistics

With less access to health care and decreased availability of antibiotics, deep neck space infections are a more common complication of URI in developing nations. Pathogens not typically seen in the United States are also noted in this population (tuberculosis) and should be considered.

A tertiary hospital in Freiburg, Germany, studied deep neck infections occurring over 8 years.[7] Of the 234 documented infections, 15 (6.4%) were RPA. Although no subgroup analysis was specifically performed for RPA, one interesting finding was a higher-than-expected rate of B henselae infection (catscratch disease) and cervical tuberculosis. Thus, the treating physician should consider all infectious etiologies when evaluating patients in whom atypical infections are a concern.

A study from India also described a socioeconomic correlation with deep neck abscesses.[8] Most patients with RPA were of low socioeconomic status, which was theorized to contribute to the incidence of abscesses in addition to poor dental hygiene and a lack of healthcare access.

Age- and sex-related demographics

RPA is almost exclusively a pediatric diagnosis. Most occur in children aged 6 months to 6 years (mean age, 3-5 years).[4, 5, 9, 9] Other deep neck abscesses (eg, parapharyngeal and peritonsillar) are observed more frequently in adults and older children.

Although no sex predilection has been described in the literature, several studies have noted a higher incidence of deep neck infections in boys. In a large national database, 63% of patients were male.[4]

Prognosis

In uncomplicated cases of RPA in a relatively healthy patient, the prognosis for complete recovery without sequelae is excellent, though complicated cases may be associated with significant mortality and morbidity. In patients with complications such as carotid artery infection, jugular vein thrombosis, or mediastinitis, mortality can approach 20-60%.

Total hospital stays for both conservative and surgical management tend to be, on average, in the range of 3-6 days, though some stays have been reported to exceed 30 days.[10, 11]  There are also studies that reported statistical insignificance with respect to length of stay and management type. Except in the most severe or complicated cases, patients are treated with intravenous antibiotics alone or surgery and can return home shortly thereafter without significant morbidity.

In a study of 2181 children with cervical abscesses, Harounian et al found that major contributors to length of stay included operating time, days of postoperative ventilation, and length of time from admission to surgery.[12] Younger children (< 2 years) had both a longer wait time until surgery (1.4 vs 1.1 days) and a prolonged length of stay (4.3 vs. 3.4 days).

Finally, the overall recurrence rate has been estimated to be in the range of 1-5%; in those circumstances, further management must be pursued.[13]

Patient Education

Advise a follow-up appointment for parents or caregivers of children diagnosed with URIs that do not follow an appropriate course of resolution.

Advise parents or caregivers to return immediately if the patient develops clinical manifestations of deep neck space infection, such as difficulty swallowing, swelling in the back of throat or neck, muffled voice, jaw or neck stiffness, or worsening of symptoms.

Advise parents to remain especially alert for signs of airway compromise, such as shortness of breath, drooling, or noisy breathing.

 

Presentation

History

In patients presenting with concern for retropharyngeal abscess (RPA), the history is not always straightforward . Symptoms (in decreasing order of incidence) can include the following:

  • Fever
  • Sore throat
  • Dysphagia
  • Trismus
  • Decreased appetite
  • Voice change
  • Odynophagia
  • Neck pain
  • Irritability
  • Difficulty in breathing

A review by Grisaru-Soen et al revealed fever (70%) and neck pain (62%) to be the most common symptoms.[9]

Small children with torticollis tend to hold the neck in a nonneutral position and do not turn the head from side to side. Patients may also complain of a muffled voice, a globus sensation, or pain in the back and shoulders upon swallowing. Finally, difficulty in breathing, drooling, or posturing may be an ominous portent of airway obstruction.

The course of RPA can be insidious; in some cases, an upper respiratory illness can precede symptoms by weeks. Accordingly, it is vital to maintain a high index of suspicion, especially in patients with upper respiratory illnesses that appear not to resolve in a normal course or to respond to conventional therapy.

Physical Examination

Most patients with an RPA are febrile upon presentation, and some may even appear toxic and irritable. Tender cervical lymphadenopathy, usually unilateral, is the most common physical finding in these patients. Patients may have decreased or painful neck or jaw range of motion. Some children may also present with a muffled "hot potato" voice (dysphonia).

Upon inspection of the oral cavity, the physician may be able to appreciate a bulge in the posterior pharyngeal wall. This retropharyngeal bulge is typically not in the midline, because of the presence of the raphe that divides the retropharyngeal space.

Patients in respiratory distress or those who present with stridor or drooling have the potential for airway compromise and should be managed expeditiously. Children should also be carefully evaluated for extension of the infection to the carotid sheath or the mediastinum.

Complications

Complications of RPAs arise from mass effect, rupture, or spread. A study of 138 patients over a 10-year period demonstrated mediastinitis to be the most common complication (nine patients); it also demonstrated that younger patients, as well as those with S aureus infections, were at higher risk for complications.[14]

The mass of the abscess in the retropharyngeal space can compress the airway. Because this is the most immediately life-threatening complication of RPA, it must be addressed first, as follows:

  • Secure the airway of patients in respiratory distress (stridor or drooling)
  • Attempt airway stabilization by first repositioning the head and neck and providing oxygen supplementation
  • If repositioning and oxygen supplementation are not successful, provide definitive airway control, which can be accomplished by means of endotracheal intubation or flexible fiberoptic intubation
  • Surgical airway intervention (tracheotomy) should be reserved for refractory cases and carried out with the assistance of a pediatric otolaryngologist

Abscess rupture can lead to asphyxiation or aspiration pneumonia. The abscess can rupture spontaneously or iatrogenically during vigorous physical examination or attempted intubation. Chest radiography is indicated to assess for pneumonia after abscess rupture. Abscess rupture requires aggressive airway management, including deep suctioning, broad-spectrum antimicrobial therapy, or both.

Infection can also spread either laterally and posteriorly to adjacent structures in the neck, or it can progress inferiorly to the mediastinum. Lateral spread can involve the carotid sheath, where it can cause vascular compromise. One case study detailed a pseudoaneurysm of the internal carotid artery secondary to RPA.[15]

Posterior spread of infection can also affect the cervical spine. Osteomyelitis necessitates long-term antibiotic therapy; erosion of ligaments can cause subluxation and subsequent spinal cord injuries. Destruction of the transverse ligament of the atlas has been known to cause atlanto-occipital dislocation.

Inferior spread of infection can cause several life-threatening complications. Chest radiography is indicated in the initial workup when concern is elicited. Inflammation in the mediastinum can cause mediastinitis, purulent pericarditis, pericardial tamponade, bronchial erosion, and mediastinal abscess. Spread to the adjacent pleura can cause pleuritis, pyopneumothorax, or empyema. In addition to antibiotic therapy, drainage of purulence via pericardiocentesis, pericardial window, chest tube thoracostomy, or open thoracotomy may be necessary.

Finally, infection also can evolve into overwhelming sepsis or necrotizing fasciitis in the neck or mediastinum.

 

DDx

Diagnostic Considerations

In addition to the conditions listed in the differential diagnosis below, other medical problems to be considered include the following:

  • Branchial cleft cyst
  • Epstein-Barr virus infection
  • Ludwig angina
  • Retropharyngeal hematoma
  • Retropharyngeal thyroid tissue
  • Retropharyngeal tumor
  • Tendonitis of longus colli muscle
  • Thyroglossal duct cyst

Differential Diagnoses

 

Workup

Laboratory Studies

Laboratory findings in cases of retropharyngeal abscess (RPA) are nonspecific. White blood cell (WBC) counts can be elevated (mean, 17,000/μL; range, 4000-45,000/μL). In a study of 2181 children with cervical abscesses, Harounian et al found the younger cohort (< 2 years of age) to have a higher preoperative WBC count (20.7 vs 17.5).[12]

Radiography

Lateral soft-tissue neck radiography may be helpful in making the diagnosis of RPA. This study is best obtained during inspiration with the neck held in normal extension. An RPA occupies the soft-tissue space that can be observed between the radiolucent airway (ie, pharynx and trachea) and the spine. Widening of these soft tissues (see the image below) is pathologic until proved otherwise.

Plain lateral neck x-ray. Top radiograph reveals w Plain lateral neck x-ray. Top radiograph reveals widening of soft tissues, with anterior airway displacement. Careful examination of this film also reveals gas in soft tissues. Bottom radiograph reveals soft tissue widening at C2.

Measured at the level of C2, the distance from the anterior surface of the vertebra to the posterior border of the airway should be less than 7 mm, regardless of the patient's age. At C6, this distance should be less 14 mm in children younger than 15 years. A distance of 22 mm is considered normal in an adult. A simpler (but less precise) rule is that the soft-tissue plane should be less than half the width of the corresponding vertebral body.

A plain film may also demonstrate gas or a foreign body in the retropharyngeal space. The normal spinal lordosis may also be reversed. With a child's head extended, the width of the soft tissue is no more than a vertebral body width in an average child.

Unfortunately, lateral plain radiography is not very sensitive or specific, with a false-negative rate as high as 33%. Poor neck extension or an expiratory view that results in a falsely narrowed airway can also produce a false-positive result. One study detailed three cases in which plain radiography missed three RPAs because of nasopharyngeal location.[16]

Chest radiography should be performed if mediastinal or pulmonary involvement is suspected. Furthermore, patients who undergo transcervical or transoral drainage of RPA and do not completely recover as expected should undergo chest imaging to rule out a developing mediastinitis or pneumonia.

Computed Tomography

Computed tomography (CT) is currently the imaging modality of choice for pediatric RPA. CT of the neck with intravenous (IV) contrast should be obtained to help demarcate the lesion and determine whether vascular involvement is present. The radiologist should be informed of the purpose of the study in advance because a standard CT scan of the neck may not employ thin enough slices (3-5 mm) and may not scan the entire extent of the retropharyngeal space (skull base to T2).

CT may be able to determine the presence of an abscess and help distinguish cellulitis from abscess because there may be an area of central lucency. It is typically an area of low attenuation (see the images below), surrounded by an enhanced ring. Gas is sometimes present within the abscess cavity, and the nearby soft tissues are edematous with obliteration of fat planes. Neighboring structures, including the airway, can also be compressed. This study can also assist in determining the location and extent of the abscess and the presence of infectious complications.

Contrast axial CT scan demonstrates left-side retr Contrast axial CT scan demonstrates left-side retropharyngeal abscess with central hypoattenuation.
Contrast sagittal CT scan demonstrates central hyp Contrast sagittal CT scan demonstrates central hypodensity with prevertebral soft-tissue stripe widening and oropharyngeal air column narrowing consistent with retropharyngeal abscess formation.

CT also provides much more information than plain radiography. Depending on the study, its sensitivity can exceed 90%.[9]  The positive predictive value has been estimated at 82%, and the negative predictive value has been estimated at 100%.[17]

Shefelbine et al, in a case series of 30 pediatric patients with RPA,[18]  concluded that a low attenuation focus with rim enhancement on CT indicates a presuppurative or suppurative lymph node. They also suggested that children with a hypodense focus diameter smaller than 2 cm often respond to IV antibiotic therapy, whereas children with a hypodense focus diameter larger than 2 cm likely require surgical intervention.

In contradistinction, Malloy et al reported a lack of correlation between CT findings and the presence of purulence at the time of surgical drainage.[19]  They found no statistically significant differences in size, rim enhancement, and prevertebral edema between the purulent and nonpurulent groups.

Kirse and Roberson's series reported that scalloping is the most useful characteristic on CT imaging.[20]  Although rim enhancement was helpful, scalloping (irregularity of the abscess wall) had a stronger association with finding purulence at the time of surgery. The investigators also found that retropharyngeal edema was present in all patients in their series and was not helpful in distinguishing abscess formation from phlegmon.

Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) produces images superior to those produced by the other studies; however, it is usually unnecessary and is rarely used unless there is concern that the abscess has spread to the central nervous system (CNS). Additionally, this study requires a protracted time during which the patient is in an unmonitored setting. Finally, children usually require sedation for this test, which is also dangerous in any patient with a potentially unstable airway.

Ultrasonography

Ultrasonography (US) has been suggested for use in deep neck space infections. The advantages of this modality are portability and lack of radiation exposure. It can also be less traumatic to children, rarely requiring the use of sedation. In experienced hands, US has the potential to determine the presence and location of an abscess and to allow the clinician to distinguish abscess formation from cellulitis. For surgical planning, however, US provides only limited assistance.

Histologic Findings

Purulent abscess contents should be cultured sent for Gram stain and acid-fast stains so that the etiology of the infection can be established; this permits a targeted and selective choice of antibiotic as well as assists in the determination of the appropriate duration and route (IV or oral) of antibiotic therapy.

 

Treatment

Approach Considerations

The first priority in treating a patient with a suspected retropharyngeal abscess (RPA) is to determine airway stability. If the patient has symptoms or signs of airway compromise, this particular concern becomes the top priority, and modalities to stabilize the airway should be sought on an urgent basis.

Surgical vs medical management

The success of surgical intervention as compared with medical therapy in RPA has been a topic of controversy and the core subject of several studies. In a national series, Lander et al found that 43% of patients underwent surgical drainage.[4]  Grisaru-Soen et al found no difference between surgical intervention and medical therapy with respect to hospital stay.[9]  Johnston et al found that nine of 22 patients with RPA could be discharged after medical therapy alone, with a hospital stay comparable to that of surgical therapy.[21]

The low specificity of computed tomography (CT) led investigators to try for a better way of defining a unique set of criteria that could more effectively determine which patients require surgical drainage. A retrospective study by Page et al summarized the controversy and suggested several criteria, including the following[22] :

  • Retropharyngeal bulge and trismus were findings that suggested true abscess formation as opposed to phlegmon
  • The presence of rash was negatively associated with abscess formation and should alert the clinician to consider other etiologies, such as  Kawasaki disease or scarlet fever
  • With respect to radiographic criteria, the authors found cross-sectional area to be the most reliable predictor of abscess formation; however, this parameter had only a 68% chance of finding purulence intraoperatively in patients with positive CT findings
  • The authors also commented on male predominance and the typical age range of patients (>5 years) with RPA, but these factors cannot be reliably used for diagnosis

Although patients receiving surgical care still require antibiotic therapy, medical management alone may be attempted in some situations. Small abscesses (< 2 cm) that do not show signs of infectious complications or severe symptoms are generally treated with a medical trial of intravenous (IV) antibiotics for 24-72 hours and are followed closely by pediatric otolaryngologists for adequate clinical progression. 

McClay et al described a series of 11 pediatric patients with radiographic evidence of deep neck abscess but without severe symptoms who were treated with IV antibiotics alone (no surgical intervention).[23]  Ten of the 11 patients responded, and no surgical therapy was necessary. All abscesses had a retropharyngeal component if they were not completely retropharyngeal. Clindamycin with or without cefuroxime was the primary medical therapy in this series.

Wong et al presented a retrospective case-control study that included 54 children with abscesses.[24]  Of the 54 subjects, 13 required operative drainage, and in 10 of the 13, previous medical management had failed. The authors advocated a trial of empiric antibiotics for stable children, especially those with small abscesses.

Khudan et al explored conservative management for uncomplicated abscesses up to 4.5 cm in size and found that most can be managed effectively with conservative therapy and without undue morbidity or requirement for surgery.[11]

Medical Care

As noted, if the patient has symptoms or signs of airway compromise, stabilization on an emergency basis is mandatory.

After appropriate blood tests (complete blood count [CBC] with differential, inflammatory markers, and blood cultures) are ordered, empiric antibiotic therapy is initiated. Broad-spectrum coverage is typically indicated in the initial management of RPA.

Although penicillin G and metronidazole were once considered the mainstays of therapy, the increasing presence of beta-lactamase–producing bacteria forced practice away from this combination. Treatment may be initiated with a beta-lactamase–resistant combination penicillin (eg, ticarcillin-clavulanate, piperacillin-tazobactam, or ampicillin-sulbactam). In some cases, when concern about methicillin-resistant S aureus (MRSA) is present, treatment is likely to involve clindamycin or vancomycin.

The microbiology of RPA commonly includes multiple pathogens, most frequently gram-negative rods and anaerobes. Sole medical management is also typically employed in a monitored hospital setting for up to 72 hours to determine its adequacy; surgical intervention is often indicated if the clinical picture does not improve with antibiotic therapy. It is also important to consider the transition from IV to oral antibiotics; patients typically can be discharged a few days after admission but often are kept on antibiotics for several days after discharge.

Surgical Care

Transoral vs transcervical surgical approaches

Kirse and Roberson reported great success with transoral drainage in pediatric patients with RPA and stated that it should be the preferred approach in this population.[20] They found it to be the safest approach in pediatric patients if CT revealed that the abscess was medial to the great vessels and was a confined process (within an inflammatory rind). Abscesses with extensive spread and those involving multiple deep spaces must be incised and drained via an external approach as well as a transoral approach, as deemed clinically necessary.

Transoral technique

Transoral needle aspiration and/or incision and drainage (I&D) may be used in the management of RPA. This technique should only be performed by a qualified pediatric otolaryngologist in the operating room (OR).

After endotracheal intubation, a McIvor mouth prop is placed into the oral cavity to allow adequate access to the posterior pharyngeal wall; 0.5% lidocaine with 1:20,000 epinephrine can be injected submucosally for additional hemostatic effect.

The RPA can be localized by palpation to determine the area of greatest fullness and fluctuance. Either CT or ultrasonography (US) may be used to help guide aspiration. Suryadevara and Kellman described a case of transoral incision and drainage with assistance from the InstaTrak image guidance system (CT-based).[25] An 18-gauge needle can be introduced under direct visualization, which should reveal purulent material. Aerobic and anaerobic cultures should be sent from the aspirate for pathologic analysis.

Once the RPA pocket has been identified, a vertical incision is made with an electrocautery device. A tonsil clamp is used to break up loculations within the abscess pocket. The wound bed is then copiously irrigated with normal saline.

Transcervical technique

Transcervical I&D may be performed in the management of RPA. Classically, this approach is followed when infection extends inferior to the hyoid bone. This technique should only be performed by a qualified pediatric otolaryngologist in the OR.

After endotracheal intubation, the head is turned away from the operative site. A modified apron incision is designed and marked along the anterior neck. Subplatysmal flaps are raised, and dissection is carried to the anterior border of the sternocleidomastoid, which is retracted laterally. The carotid sheath is retracted laterally to allow blunt opening and evacuation of deep neck spaces. Specimens from the abscess pocket are sent for aerobic and anaerobic culture and pathologic analysis. The wound bed is then irrigated copiously with antibiotic-impregnated saline.

Penrose drains are left in the neck to allow passive egress of fluid. The remainder of the neck is closed in layers. The neck is dressed with fluffed gauze and a stockinette dressing.

If mediastinal involvement is present, consultation with pediatric surgery or pediatric thoracic surgery is strongly advised. Mediastinal washout and thoracotomy may be indicated concomitantly, if deemed clinically necessary.

If the primary admitting facility does not have the capability or personnel needed to drain an RPA adequately, the patient should be transferred to a tertiary care center with pediatric otolaryngology availability. However, transfer should take place only if the airway has already been secured or if the patient is stable enough for medical transport to another facility.

Diet

Patients with RPA should not ingest anything orally (nil per os [NPO]) until the possibility of surgical intervention is determined. Postoperatively, children may be started on a clear liquid diet and advanced slowly to a soft diet over a period of several days so as to allow appropriate healing of the surgical site (particularly when intraoral approaches are employed).

Activity

Bed rest is advised for patients with RPA so as to avoid airway compromise during activity. Patients should be allowed to remain supine for optimal airway positioning.

Consultations

Consultations with the following appropriate specialists are mandatory and should take place on an urgent or emergency basis. The primary team should include a pediatrician, and one of or more of the following should be done if appropriate: 

  • Obtain a surgical consultation with a specialist in pediatric otolaryngologic surgery
  • Inform a pediatric anesthesiologist about the patient regarding perioperative airway management 
  • Consider a pediatric radiology consultation to order or interpret imaging studies
  • Request assistance from pediatric infectious disease specialists to help determine appropriate antibiotic treatment therapies and regimens

Long-Term Monitoring

Patients with an RPA should be admitted to a monitored setting or taken directly to the OR for urgent or emergency I&D, if clinically indicated. Most patients can be monitored safely in the pediatric inpatient wards, but patients who are unstable, are at the extremes of age, or have multiple comorbidities may require monitoring in the pediatric intensive acre unit (ICU).

At the time of discharge, transitioning to an oral equivalent of the antibiotic should be considered. Patients with a complicated RPA may need IV access (eg, a peripherally inserted central catheter [PICC]) for prolonged antibiotic courses that may last as long as 4-6 weeks, as determined by pediatric infectious disease specialists.

 

Medication

Medication Summary

Initiate empiric parenteral antibiotic therapy early in patients with concern for RPA. Provide broad-spectrum coverage for gram-positive, gram-negative aerobes, and anaerobes.

Although penicillin G and metronidazole were once considered the mainstays of therapy, the increasing presence of beta-lactamase–producing bacteria forced practice away from this combination. Treatment may be initiated with a beta-lactamase–resistant combination penicillin (eg, ticarcillin-clavulanate, piperacillin-tazobactam, or ampicillin-sulbactam). In some cases, when concern for MRSA is present, treatment would likely be managed with clindamycin or vancomycin.

Penicillins, Amino

Ampicillin and sulbactam (Unasyn)

Ampicillin is a semisynthetic penicillin and is bactericidal, inhibiting cell wall synthesis. Sulbactam is a beta-lactamase inhibitor. 3 g Unasyn contains 2 g ampicillin and 1 g sulbactam.

Amoxicillin/clavulanate (Augmentin, Augmentin ES-600, Augmentin XR)

Amoxicillin binds to penicillin-binding proteins, thus inhibiting final transpeptidation step of peptidoglycan synthesis in bacterial cell walls; addition of clavulanate inhibits beta-lactamase-producing bacteria, allowing amoxicillin extended spectrum of action.

Glycopeptides

Vancomycin (Vancocin, Firvanq)

Vancomycin inhibits cell-wall biosynthesis; blocks glycopeptide polymerization by binding tightly to D-alanyl-D-alanine portion of cell wall precursor.

Lincosamides

Clindamycin (Cleocin, Cleocin Pediatric, ClindaMax Vaginal)

Clindamycin inhibits bacterial growth, possibly by blocking dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest.

Cephalosporins, 2nd Generation

Cefuroxime (Ceftin, Zinacef)

Second generation cephalosporin which binds to penicillin-binding proteins and inhibits final transpeptidation step of peptidoglycan synthesis, resulting in cell-wall death; resists degradation by beta-lactamase.

Cefoxitin (Mefoxin)

Second-generation cephalosporin indicated for gram-positive cocci and gram-negative rod infections. Bactericidal and inhibits cell wall synthesis.

Penicillins, Extended-Spectrum

Piperacillin/tazobactam (Zosyn)

Antipseudomonal penicillin plus beta-lactamase inhibitor which prevents biosynthesis of cell wall mucopeptide and is effective during the stage of active multiplication. Zosyn 3.375 contains 3 g of piperacillin and 0.375 g of tazobactam.

Ticarcillin and clavulanate potassium (Timentin)

Inhibits biosynthesis of cell wall mucopeptide and is effective during stage of active growth. Antipseudomonal penicillin plus beta-lactamase inhibitor that provides coverage against most gram-positive and gram-negative organisms and most anaerobes. Timentin 3.1 g contains 3 g of ticarcillin and 0.1 g of clavulanate.

 

Questions & Answers

Overview

What is pediatric retropharyngeal abscess?

What is the pathophysiology of pediatric retropharyngeal abscess?

What causes infection in the pathogenesis pediatric retropharyngeal abscess?

What are the possible complications of pediatric retropharyngeal abscess?

What causes pediatric retropharyngeal abscess?

What are iatrogenic causes of pediatric retropharyngeal abscess?

What are the risk factors for pediatric retropharyngeal abscess?

What is the prevalence of pediatric retropharyngeal abscess in the US?

What is the global prevalence of pediatric retropharyngeal abscess?

Which patient groups have the highest prevalence of pediatric retropharyngeal abscess?

What is the prognosis of pediatric retropharyngeal abscess?

What is included in patient education about pediatric retropharyngeal abscess?

Presentation

Which clinical history findings are characteristic of pediatric retropharyngeal abscess?

Which physical findings are characteristic of pediatric retropharyngeal abscess?

What causes complications from pediatric retropharyngeal abscess?

How is the mass of the pediatric retropharyngeal abscess treated?

How is rupture of a pediatric retropharyngeal abscess treated?

How is infection treated in pediatric retropharyngeal abscess?

DDX

Which conditions are included in the differential diagnoses of pediatric retropharyngeal abscess?

What are the differential diagnoses for Pediatric Retropharyngeal Abscess?

Workup

What is the role of lab testing in the workup of pediatric retropharyngeal abscess?

What is the role of radiography in the workup of pediatric retropharyngeal abscess?

What is the role of CT scanning in the workup of pediatric retropharyngeal abscess?

What is the role of MRI in the workup of pediatric retropharyngeal abscess?

What is the role of ultrasonography in the workup of pediatric retropharyngeal abscess?

What is the role of histology in the treatment of pediatric retropharyngeal abscess?

Treatment

How is pediatric retropharyngeal abscess treated?

What is the efficacy of surgery for pediatric retropharyngeal abscess?

Which factors support a diagnosis of pediatric retropharyngeal abscess?

What is the role of surgery in the treatment of pediatric retropharyngeal abscess?

How is a pediatric retropharyngeal abscess aspirated?

What is the role of incision and drainage in the treatment of pediatric retropharyngeal abscess?

When is patient transfer required for the treatment of pediatric retropharyngeal abscess?

Which dietary modifications are used in the treatment of pediatric retropharyngeal abscess?

Which activity modifications are used in the treatment of pediatric retropharyngeal abscess?

What are the indications of infection in the deep spaces in pediatric retropharyngeal abscess?

Which specialist consultations are beneficial to patients with pediatric retropharyngeal abscess?

What is included in the long-term monitoring of pediatric retropharyngeal abscess?

Medications

What is the role of medications in the treatment of pediatric retropharyngeal abscess?

Which medications in the drug class Penicillins, Amino are used in the treatment of Pediatric Retropharyngeal Abscess?

Which medications in the drug class Penicillins, Extended-Spectrum are used in the treatment of Pediatric Retropharyngeal Abscess?

Which medications in the drug class Cephalosporins, 2nd Generation are used in the treatment of Pediatric Retropharyngeal Abscess?

Which medications in the drug class Lincosamides are used in the treatment of Pediatric Retropharyngeal Abscess?

Which medications in the drug class Glycopeptides are used in the treatment of Pediatric Retropharyngeal Abscess?