Emergency physicians (EPs) are expected to have a thorough working knowledge of life-threatening pathologic conditions that may typically be seen in an ED only once in a year or even once in a career. Deep space infections of the neck, recognized and described since the time of Galen in the second century, are one such entity.1
These infections are twice as common in males as in females. Although the patient age ranges from 11 months to 91 years, the average age of presentation is in the third decade of life. Although the incidence of deep space neck infections has plummeted with the advent of antibiotics and improvements in dental hygiene, they still occur with some regularity and when they do, are associated with high morbidity and occasionally mortality. Rapid diagnosis and effective treatment depend on a high degree of clinical suspicion and an understanding of the need for and type of timely intervention.
Infections that spread along the fascial planes and spaces of the head and neck can be either superficial or deep space infections. Superficial neck infections do not significantly differ from other superficial skin infections, and are frequently characterized by erythema with central induration and respond well to simple incision and drainage. In contrast, deep neck space infections are difficult to diagnose in their early stages. Occurring in a potential space bounded by the deep cervical fascia, deep space neck infections lack outward, grossly visualized physical findings. Whereas a “typical” abscess may lead to external rupture, the tough neck fascia prevents outward extension and leads to rapid deep spread.2 So what initially may begin as a simple dental infection, minor trauma, or upper respiratory illness, may progress to abscess formation in the deep neck spaces with the potential for significant complications, such as descending mediastinitis, jugular vein thrombosis, or acute airway collapse.3 Most of the current literature on deep space neck infections is based on retrospective studies published in surgery journals; however, these patients often initially present to the ED.
Based on literature reports, the source of deep space neck infection in adults is identified in 30% to 90% of cases.4 Infections of the submandibular space are the most common site, and are caused by an odontogenic in up to 85% of cases, with 65% attributable to dental caries.5 In 68% of cases, the lower third molar was the involved tooth.5 Deep space neck infection can also result from laceration of the floor of the mouth, mandibular fracture, tumor, lymphadenitis, sialadenitis, patient injection of intravenous (IV) drugs, systemic infection, hematogenous spread of infection, and foreign body ingestion.4,6 In adults, branchial sinuses, thyroglossal duct cysts, tuberculosis, and malignancies can masquerade as infections or can present with secondary infection.7-9 In children, acute tonsillitis and pharyngitis remain the most commonly identified inciting conditions.9
Larawin et al10 reported the incidence of infection in children and adults in a retrospective study of 103 cases occurring at a teaching hospital. In this study, Ludwig’s angina was seen in 37% of cases, submandibular space infection in 27%, masticator space infection in 13%, parapharyngeal abscess in 11%, parotid space abscess 6%, retropharyngeal abscess in 5%, and the prevertebral in 1%.10 The predominant site of neck abscesses in children was in the retropharyngeal or parapharyngeal spaces, followed by the anterior or posterior triangle.11,12 While most deep neck infections will involve a single anatomic space, two or more spaces were involved in nearly 30% of patients in one retrospective study.6
In adults, the most common presenting complaint in deep space neck infection is odynophagia, affecting 83.9% of patients. Other symptoms include dysphagia (71%), fever (67.7%), neck pain (54.8%), swelling (45.2%), trismus (38.7%), and respiratory distress (9.7%).10 Children and geriatric patients (age 65 years or older) tend to have a more subtle presentation. Pediatric patients are seldom able to verbalize their symptoms and their history commonly includes recent upper respiratory infection with fever, neck mass or swelling, and difficulty eating and drinking.11
As increased disease severity is linked to lack of preventive dental and primary care and delayed presentation, patients with severe infections tend to be of low socioeconomic status.7,13,14 Immunosuppression and the use of multiple medications have also been correlated with increased rates of infection.2 Deep space infections in diabetic patients, who have greater susceptibility to infection and are likely to be older at diagnosis, tend to be more severe and result in more serious complications, prolonged hospital stays, and higher mortality.1 Additionally, the bacterial flora may be unusual in diabetic patients, making culture and sensitivity more important for directed antimicrobial therapy.8 Interestingly, in one review, a seasonal distribution of cases was found with the highest incidence in autumn (46.2%) and far fewer cases in winter (15.6%).6