Mixed infection of Actinomyces israelii and Fusobacterium nucleatum presenting as a neck mass.

This report presents the case of a mixed infection of Actinomyces israelii and Fusobacterium nucleatum, presenting as an extensive neck mass progressing through tissue planes and causing bony destruction. Despite multiple abscess aspirates, imaging and serological investigations, the causative organisms proved elusive over the course of the patient's long admission, only to be identified postdischarge. The patient was successfully initiated on a prolonged course of intravenous antibiotics and did not suffer from any complications. This report aims to raise awareness of the presentation, pathogenicity and treatment of Actinomyces and Fusobacteria infections, given a notable difficulty in diagnosis.