Neck Space Infections - Symptoms, Diagnosis, and Management

Introduction

Neck infections are classified as superficial and deep infections. Deep neck space infections include infection or abscess formation in the deeper structures, fascial planes, and spaces in the neck. The deep cervical fascia creates spaces for the infection to spread and develop. Most deep-space neck infections are seen in the peri-tonsillar, parapharyngeal, or retropharyngeal spaces. These infections, if not treated, can cause sepsis and airway obstruction, followed by death.

What Is the Etiology of Neck Space Infections?

Anatomy:

Many spaces or chambers of the neck can lead to infection. The neck is divided into deep structural units by fascial layers. The carotid sheath and pre-tracheal fascia are the skeletal muscles of the cervical spine. The spaces of the neck are again classified as suprahyoid and infrahyoid spaces. The suprahyoid spaces include the following spaces:

• Masticator space.

• Pterygomandibular space.

• Superficial temporal space.

• Deep temporal space.

• Submandibular space.

• Submental space.

• Sublingual space.

• The lateral pharyngeal is called the parapharyngeal space.

The infrahyoid spaces include the following spaces:

• Pretracheal space.

• Perivertebral space.

• Carotid space.

• Retropharyngeal space.

• Danger space.

• The common location for deep space infections is the submandibular space, the masticator space, the parapharyngeal space, and the retropharyngeal space.

What Are the Types of Neck Infections?

Parapharyngeal and Peritonsillar Space Infection:

• The parapharyngeal space is an inverted cone-type space, with the skull as the base and the hyoid bone as the apex. The styloid process divides para pharyngeal space into anterior and posterior compartments.

• Parapharyngeal space abscess is a complication of tonsillitis, dental infections, or supraglottis.

• Infections spread directly from the peritonsillar space.

• The parapharyngeal space connects with the retropharyngeal and the submandibular space.

• A peritonsillar abscess is also called ‘quinsy.’ Infection is seen between the lateral aspect of the tonsil and the medial aspect of the superior constrictor muscle.

Retropharyngeal Space Infection:

• The retropharyngeal space is from the base of the skull to the posterior mediastinum.

• Retropharyngeal abscesses are primarily seen in children and as respiratory tract infections in the retropharyngeal lymph nodes. The retropharyngeal lymph nodes show regression by five years of age.

• Retropharyngeal abscesses are less common in adults and are caused by trauma or occur directly from cervical spinal disc infection or osteomyelitis.

Submental and Submandibular Spaces:

• Ludwig’s angina is gangrene and cellulitis of the floor of the mouth involving the three parts of the floor of the mouth, which include submental, sublingual, and submandibular tissues on both sides.

• The most common source of infection is a dental infection due to posterior mandibular molars.

Cervical Necrotizing Fasciitis:

• Fascitis is a rapidly progressive infection of the superficial tissue due to toxins from bacteria.

• The toxins lead to localized necrosis of the subcutaneous tissue and fascial structures. Cervical necrotizing fasciitis rarely occurs but has high morbidity and mortality.

• A deep space neck infection can lead to cervical necrotizing fasciitis.

What Is the Pathophysiology of Neck Space Infections?

The infection spreads to the deep space of the neck directly. The disease is spread through oropharyngeal infections like tonsillitis, oral infections, or skin infections. Direct extension from the oral cavity is seen in tonsillitis in children. Neck trauma that is blunt and penetrating can cause infection in the deep space of the neck. Infection also spreads through the lymphatic system. Cellulitis turns into phlegmon, which is an acute inflammation of soft tissue. If phlegmon is not treated, it turns into an abscess. Cervical lymphadenitis is the common cause of deep-space neck infections. In lymphadenitis, infection suppurates in retropharyngeal or parapharyngeal lymph nodes. Whereas in adults, lymphadenitis occurs due to tonsillar or dental reasons.

Causative Organisms:

• Deep space neck infections are polymicrobial. Streptococci and Staphylococcus aureus cause these infections, and anaerobes are the most common causative organisms.

• Anaerobic bacteria cause infections of dental origin, and Streptococcus is the causative organism in pharynx-tonsillar infections.

• Staphylococcus aureus is found in deep-space neck infections in children. Klebsiella pneumoniae is seen in diabetic patients.

What Are the Risk Factors for Neck Space Infections?

Risk factors for deep neck space infections are as follows:

• Male.

• Recurrent peritonsillar abscesses.

• Smoker.

• Poor oral hygiene.

• Intravenous drug use.

• Immunocompromised status due to steroid use or HIV (human immunodeficiency virus).

• Type 2 diabetes mellitus.

What Are the Clinical Features of Neck Space Infections?

Symptoms of deep-space neck infections are as follows:

• Fever.

• Throat ache.

• Dysphagia or difficulty swallowing.

• Neck swelling.

• Chest pain.

Other details to be obtained are smoking status, history of recurrent throat infections, previous hospitalizations for neck infections, and drug history. Clinical examination shows the following features.

• Trismus is difficult to open the mouth.

• Torticollis is the contraction of the neck muscles.

• The swelling at the floor of the mouth.

• Cervical lymphadenopathy.

• Drooling.

• Tonsillar enlargement or bulging in the peritonsillar space.

• Halitosis is a foul odor.

• Examination of the neck shows cervical lymphadenopathy, a palpable mass, and reduced movement.

What Are the Diagnostic Tests for Neck Infections?

Investigations:

Laboratory investigations include the following:

• Full blood count shows increased white blood cells.

• C-reactive protein is raised in the acute inflammatory response.

• Urea and electrolytes show acute renal failure due to sepsis.

• Blood cultures can show the presence of aerobic and anaerobic bacteria.

• Flexible Nasal Endoscopy (FNE): Flexible nasal endoscopy requires the insertion of an adjustable camera to view the larynx. In addition, asymmetrical bulging of the pharyngeal wall shows laryngeal stenosis, which might lead to airway compromise.

Following imaging techniques help in diagnosis:

• Lateral neck X-ray to assess a retropharyngeal abscess.

• A computed tomography neck scan with contrast detects abscess formation.

• A computed tomography (CT) chest with contrast helps to identify the extension of infection into the mediastinum.

• Ultrasound neck.

How to Manage Neck Space Infections?

Immediate Management:

Deep space neck infections are life-threatening and need immediate assessment.

• Airway assessment.

• Broad-spectrum intravenous antibiotics should be administered.

• A CT scan of the neck and chest with contrast should be done.

Non-operative Management:

Non-operative management is done for abscesses less than 2.5 cm in diameter.

Surgical Management:

If a CT scan shows an abscess more than 2.5 cm in diameter, the patient will need surgical incision and drainage.

What Are the Complications of Neck Space Infections?

Complications of deep space neck infections include the following:

• Sepsis.

• Acute airway obstruction.

• Mediastinal abscess.

• Carotid artery aneurysm.

Conclusion

Deep neck space infections are abscess formation in the deep spaces in the neck. Deep space neck infections are life-threatening and need immediate assessment as there is a risk of airway compromise. Deep space neck infections are managed with airway management, broad-spectrum antibiotics, and surgical drainage of any abscess.