Head and neck mucosal manifestations of microbial infection: clinical presentation, histological features and diagnostic aids

Manifestations of microbial infection in the head and neck mucosa present significant challenges in diagnosis, often due to their non-specific clinical, imaging and histological appearances. Their presentation as ulcerated or necrotic lesions, combined with lymphadenopathy mimic malignant processes, resulting in further challenges in diagnosis. Additionally, the need for a microbial infection diagnosis is overshadowed by the urgency to confirm or exclude a cancer diagnosis, resulting in ancillary investigations catering mostly to the latter. The necessity for accurate and timely diagnosis of microbial infections is emphasized, especially for acute necrotizing infections due to anatomical proximity to vital structures of the cranial cavity and neck. To enable this, a reasonable level of experience and knowledge of the clinical and histological appearances of a range of microbial infections presenting in the head and neck region is essential. Histological skills, together with emphasis on detailed clinical and imaging features, and history should enable accurate diagnosis and targeted management. The salient features of a selection of viral, fungal, bacterial and protozoan infections presenting in the head and neck mucosal sites, their differential diagnoses and investigative tools are discussed.