Ludwig's angina can be life-threatening cellulitis of the soft tissue involving the floor of the mouth and neck. It was named after a German physician, Wilhelm Friedrich von Ludwig who first described the condition in 1836. It involves 2 compartments on the floor of the mouth including the sublingual and submaxillary space bilaterally. Infection in the lower molar is the most common cause of Ludwig’s angina. The infection is rapidly progressive leading to aspiration pneumonia and airway obstruction. People often describe any infection in the sublingual and submaxillary space as Ludwig’s angina. However, the classic diagnosis should include rapidly progressive cellulitis of the submandibular space which does not involve the lymphatic system without abscess formation. In addition, it should be bilateral and involve both the sublingual and submaxillary space.
The most common cause is secondary to dental disease in the lower molars which accounts for over 90% of cases. Any recent infection or injury to the area may predispose the patient to develop Ludwig's angina. Some common etiologies include injury or laceration to the floor of the mouth, mandible fracture, tongue injury, oral piercing, osteomyelitis, traumatic intubation, peritonsillar abscess, submandibular sialadenitis, and infected thyroglossal cysts. Predisposing factors include diabetes, oral malignancy, dental caries, alcoholism, malnutrition, and immunocompromised status.
The most life-threatening complication of Ludwig's angina is airway obstruction. Prior to the development of antibiotics, mortality exceeded 50%. With antibiotic therapy, along with improved imaging modalities and surgical techniques, mortality is approximately 8%.
Ludwig's angina usually starts as a cellulitis of the submandibular space. The infection usually starts as a dental infection of the second or third mandibular molar teeth. Other sources of infection include local spread from a peritonsillar abscess or suppurative parotitis. The infection spreads medially rather than laterally because the medial side of the periodontal bones is thin. The infection initially spreads to the sublingual space and progresses to the submandibular space bilaterally. Since the infection does not spread via the lymphatic system, the infection is bilateral. Because of the location of the cellulitis, it can rapidly progress to airway compromise leading to asphyxiation. The infection is usually polymicrobial involving the oral flora. The most common organisms are Staphylococcus, Streptococcus, and Peptostreptococcus, Fusobacterium, Bacteroides, and Actinomyces. Immunocompromised patients are at higher risk of Ludwig's angina. Complications from Ludwig’s angina include aspiration pneumonia, asphyxia, and mediastinitis. Airway compromise is the leading cause of death in Ludwig's angina.
Ludwig's angina starts as cellulitis of the submandibular region and rapidly progress to cause airway obstruction. The most common presenting symptoms include neck swelling, neck pain, odynophagia, and dysphagia. People often describe the appearance as a "bull neck." Less common symptoms include mouth pain, hoarse voice, drooling, tongue swelling, and sore throat. Stridor may indicate impending airway obstruction. Patients will not have truisms unless the infection has spread into the parapharyngeal space. On physical exam, patients will have a fever, submandibular swelling and tenderness, swelling to the floor of the mouth, tenderness to the involved teeth, stiff neck, edema in the upper part of the neck, and crepitus. The patient will not typically have lymphadenopathy.
A clinical diagnosis should be made based on presentation. Laboratory testing, although common in clinical practice, may be of little value as this is a clinical diagnosis. Blood cultures should be obtained to determine if there is the hematogenous spread of the infection. CT scan of the soft tissue neck with intravenous (IV) contrast is used to evaluate the severity of the infection and airway obstruction. CT is also useful to determine which patients will require surgical intervention for the formation of an abscess. Ultrasound may also be useful to identify the formation of an abscess. However, Ludwig’s angina usually does not result in an abscess formation. Therefore, it is often difficult to obtain cultures to determine what bacteria is causing the infection.
Early airway management is critical to the treatment of Ludwig’s angina as the most common cause of death is sudden asphyxiation from airway obstruction. Flexible fiberoptic nasal intubation is clinicians' favored method of intubation. The provider with the most experience should manage the airway as it will often be very challenging. Video laryngoscopy may be an option although there are no studies to date on this issue. Standard direct laryngoscope may be very challenging because of the swelling of the upper airway. It is important to manage the airway before the presence of stridor or cyanosis as these are late findings. If the patient is not able to be intubated, the next step would be an emergency tracheotomy. Cricothyrotomy is very challenging because of the edema in the neck which can obscure the anatomy.
Early broad-spectrum IV antibiotics have been shown to be helpful. For patients who are immunocompetent, a reasonable first choice would be ampicillin-sulbactam or clindamycin. Antibiotics should cover gram-positive bacteria, gram-negative bacteria, and anaerobes. For patients who are immunocompromised, the coverage should be broadened to cover for pseudomonas. Some options include cefepime, meropenem, or piperacillin-tazobactam. MRSA coverage should be considered for patients who are immunocompromised, increased risk of methicillin-resistant Staphylococcus aureus (MRSA), or prior MRSA infection. IV steroids are controversial. Several case reports have shown the decrease in the need for airway management with the use of steroids. However, more studies are needed before it becomes standard of care.
Dental extraction is recommended if the source of the infection is odontogenic. For patients who do not respond to initial antibiotics or develop a fluid collection on imaging, needle aspiration or surgical incision and drainage may be performed. Surgery is usually reserved for patients who fail medical therapy as early surgical decompression has not been shown to improve outcomes.
Differential diagnosis includes peritonsillar abscess, retropharyngeal abscess, submandibular abscess, epiglottitis, oral carcinoma, angioedema, submandibular hematoma, and diphtheria. Although Ludwig’s angina is a clinical diagnosis, it may be difficult to differentiate from other diseases initially. Imaging may be helpful in this situation as Ludwig’s angina typically does not result in abscess formation and does not involve the lymphatic system. Imaging also helps rule out other causes of the patient's symptoms.