ENT · Infectious Disease

Deep Neck Infection (Ludwig Angina)

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7

Bets

The facts most likely to be tested

1

Ludwig angina is a rapidly progressive, bilateral cellulitis of the submandibular space that typically arises from an odontogenic infection.

Confidence:
2

The most common causative organisms are polymicrobial, involving Streptococcus and anaerobic oral flora.

Confidence:
3

Patients classically present with bilateral submandibular swelling, tongue elevation, and a 'hot potato' voice.

Confidence:
4

The most critical and life-threatening complication is airway obstruction due to posterior displacement of the tongue.

Confidence:
5

The definitive management priority is securing the airway via fiberoptic intubation or tracheostomy if the airway is compromised.

Confidence:
6

Diagnosis is primarily clinical, but a contrast-enhanced CT scan of the neck is the imaging modality of choice to evaluate for abscess formation.

Confidence:
7

Initial medical management requires aggressive intravenous antibiotics covering both aerobic and anaerobic bacteria, such as ampicillin-sulbactam or clindamycin.

Confidence:

Vignette unlocked

A 34-year-old male presents to the emergency department with two days of worsening neck pain and difficulty swallowing. He reports a recent history of a painful, decayed second molar. Physical examination reveals bilateral, firm, indurated swelling of the submandibular region and a protruding, elevated tongue. The patient is drooling and speaks with a muffled 'hot potato' voice. His oxygen saturation is 94% on room air, and he appears anxious.

What is the most appropriate next step in the management of this patient?

+Reveal answer

Secure the airway via fiberoptic intubation

The patient presents with classic signs of Ludwig angina, where the primary concern is imminent airway obstruction; securing the airway takes precedence over imaging or antibiotic administration.

Mo

Depth

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High yield triage

Etiology / Epidemiology

Rapidly progressive cellulitis of the submandibular space, typically arising from odontogenic infections (second/third molars).

Clinical Manifestations

Presents with woody induration of the floor of the mouth, tongue elevation, and drooling.

Diagnosis

Diagnosis is clinical; CT scan with contrast is the gold standard to assess for abscess formation and airway compromise.

Treatment

Secure the airway first; initiate ampicillin-sulbactam or clindamycin; surgical incision and drainage if abscess present.

Prognosis

High mortality if untreated due to asphyxiation; requires ICU admission for close airway monitoring.

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Epidemiology & Etiology

Most commonly occurs in healthy adults following dental caries or recent dental procedures. It is a polymicrobial infection involving both aerobic and anaerobic flora, most notably Streptococcus and Staphylococcus species.

Pertinent Anatomy

Involves the bilateral submandibular, sublingual, and submental spaces. The infection spreads rapidly because these spaces lack physical barriers, leading to tongue displacement superiorly and posteriorly.

Pathophysiology

The infection begins as a cellulitis that rapidly progresses to a gangrenous state. The inflammatory process causes massive edema, which pushes the tongue upward and backward, creating a critical airway obstruction risk.

Clinical Manifestations

Patients present with bilateral submandibular swelling, woody induration, and trismus. Airway compromise is the primary concern, evidenced by stridor, dyspnea, and inability to handle secretions. The floor of the mouth is often raised and tender.

Diagnosis

Diagnosis is primarily clinical, but a CT scan with contrast is the gold standard to delineate the extent of the infection and identify fluid collections. Avoid plain films as they lack the sensitivity to detect early soft tissue gas or deep space involvement.

Treatment

The priority is airway protection via fiberoptic intubation or tracheostomy if necessary. Empiric IV antibiotics like ampicillin-sulbactam are required. Do not delay surgery if an abscess is identified; prompt incision and drainage is mandatory for source control.

Prognosis

Complications include mediastinitis, carotid sheath involvement, and sepsis. Patients require ICU admission for continuous airway monitoring and aggressive fluid resuscitation.

Differential Diagnosis

Peritonsillar abscess: usually unilateral with uvular deviation

Epiglottitis: presents with 'thumbprint sign' and severe odynophagia

Retropharyngeal abscess: presents with neck stiffness and prevertebral widening

Angioedema: lacks signs of infection and fever

Parotitis: localized to the parotid gland rather than submandibular space