Abstract
Deep neck infections can progress from the oral cavity and oropharynx to the posterior cervical region or mediastinum, often leading to life-threatening complications. These infections are primarily caused by bacterial pathogens, and treatment is usually directed against the bacteria and occasionally against the fungi. This article presents the cases of two geriatric patients with diabetes mellitus and a history of coronavirus disease 2019 (COVID-19). Both patients developed deep neck infections unresponsive to antibiotic and antifungal therapy with a unique progression pattern. Although they were negative for CMV IgM in blood tests, their CMV positivity was confirmed by tissue samples. After initiation of antiviral therapy, clinical improvement was achieved. Cytomegalovirus (CMV) should be considered as a potential causative agent of treatment-resistant deep neck infections, especially in patients with previous CMV exposure and immunosuppression. Tissue sampling and molecular diagnostics, such as CMV DNA PCR, play a crucial role in identifying rare pathogens when conventional tests are negative.