Anatomical risk factors for descending necrotizing mediastinitis in deep neck infections.

BACKGROUND

Descending necrotizing mediastinitis (DNM) is among the most severe complications of deep neck infections (DNI), and the anatomical pathways that predispose to mediastinal extension remain incompletely characterized in large cohorts. We aimed to identify the anatomical risk factors associated with DNM in patients with DNI.

METHODS

We retrospectively reviewed 496 consecutive patients hospitalized with DNI at a tertiary referral center between January 2015 and December 2025. Demographic data, the anatomical site of infection, the radiological dissemination pattern, surgical management, and clinical outcomes were analyzed, and patients who developed DNM were compared with those without mediastinal extension. DNM was diagnosed using the modified Estrera criteria.

RESULTS

DNM developed in 9 of 496 patients (1.81%). Retropharyngeal space involvement was identified in 6 DNM cases (66.7%): An isolated retropharyngeal abscess in 4 patients (44.4%) and a combined retropharyngeal-parapharyngeal abscess in 2 patients (22.2%); the remaining cases arose from a parapharyngeal abscess, Ludwig's angina, and a peritonsillar abscess (1 each, 11.1%). Although retropharyngeal abscess represented only 14 of 496 DNI cases (2.8%), it was the source of 44.4% of all DNM cases. Posterior mediastinal extension through the danger space was demonstrated in every retropharyngeal case. Diabetes mellitus was present in 2 DNM patients (22.2%). All 9 patients underwent aggressive surgical drainage and survived.

CONCLUSION

Retropharyngeal space involvement is the principal anatomical pathway for mediastinal extension in DNI. Early contrast-enhanced computed tomography and prompt multidisciplinary surgical drainage are essential to improve outcomes.