8-22: Deep Neck Infections

ESSENTIALS OF DIAGNOSIS

GENERAL CONSIDERATIONS

Deep neck abscesses most commonly originate from odontogenic infections. Other causes include suppurative lymphadenitis; direct spread of pharyngeal infection; penetrating trauma; pharyngoesophageal foreign bodies; cervical osteomyelitis; and intravenous injection of the internal jugular vein, especially in people with substance use disorders. Ludwig angina is the most commonly encountered neck space infection. It is a cellulitis of the sublingual and submaxillary spaces, often arising from infection of the mandibular dentition. Ludwig angina is an emergency as it may cause rapid upper airway compromise and necessitate creation of a surgical airway. Recurrent deep neck infection may suggest an underlying congenital lesion, such as a branchial cleft cyst. Suppurative lymphadenopathy in middle-aged persons who smoke cigarettes and drink alcohol regularly should be considered a manifestation of malignancy (typically metastatic squamous cell carcinoma) until proven otherwise.

CLINICAL FINDINGS

Patients with Ludwig angina have edema and erythema of the upper neck under the chin and often of the floor of the mouth. The tongue may be displaced upward and backward by the posterior spread of cellulitis, and coalescence of pus is often present in the floor of mouth. This may lead to occlusion of the airway. Microbiologic isolates include streptococci, staphylococci, Bacteroides, and Fusobacterium. Patients with diabetes may have different flora, including Klebsiella, and a more aggressive clinical course.

Patients with deep neck abscesses usually present with marked neck pain and swelling. Fever is common but not always present. Deep neck abscesses are emergencies because they may rapidly compromise the airway. Untreated or inadequately treated, they may spread to the mediastinum or cause sepsis.

Contrast-enhanced CT usually augments the clinical examination in defining the extent of the infection. It often will distinguish inflammation and phlegmon (requiring antibiotics) from abscess (requiring drainage) and define for the surgeon the extent of an abscess. CT with MRI may also identify thrombophlebitis of the internal jugular vein secondary to oropharyngeal inflammation. This condition, known as Lemierre syndrome, is rare and usually associated with severe headache. The presence of pulmonary infiltrates consistent with septic emboli in the setting of a neck abscess should lead one to suspect Lemierre syndrome or injection drug use, or both.

TREATMENT

Usual doses of penicillin plus metronidazole, ampicillin-sulbactam, clindamycin, or selective cephalosporins are good initial choices for treatment of Ludwig angina. Culture and sensitivity data are then used to refine the choice. Dental consultation is advisable to address the offending tooth or teeth. External drainage via bilateral submental incisions is required if the airway is threatened or when medical therapy has not reversed the process.

Treatment of deep neck ...