Actinomyces lymphadenitis

Abstract

Actinomyces is a gram-positive anaerobe that colonizes the human oral cavity. Its pathogenesis involves the disruption of the mucosal membrane, leading to suppuration and subsequent abscess formation, most commonly in the cervicofacial region. The bacteria form masses consisting of aggregates of branching, filamentous bacilli. They typically spread by direct tissue invasion and less commonly through hematogenous spread. Lymphatic spread is extremely uncommon. To the best of our knowledge, only two cases have been reported with lymph node involvement. Clinically, lymphadenopathy associated with Actinomyces may be misinterpreted as malignancy, causing unnecessary surgical interventions when only antibiotics are warranted. This case highlights the importance of properly diagnosing a rare phenomenon of Actinomyces lymphadenitis.

Keywords: Actinomyces; lymph node; pulmonary actinomycosis.

Figure 1.

CT of the chest. (a) Axial and (b) coronal views showing air in the subcarinal lymph node. (c) A scan after antibiotic treatment showing residual disease and improvement.