Cervical vertebral actinomycosis mimicking malignancy in a paediatric patient

Abstract

Actinomyces spp are found in the flora of the oral cavity and vagina and may cause infection with abscess formation and draining sinuses. Cervicofacial manifestations of actinomycosis involve head and neck soft tissue, however, spread to the cervical spine is rare. We report a case of an 8-year-old boy, presenting with neck pain for 1 month and denying a history of trauma or procedures. Radiography revealed an ulceration of the posterior oropharyngeal mucosa with a defect extending to the C1-C2 vertebra, mimicking a neoplastic process. The patient underwent laryngoscopy and multiple biopsies were taken from the ulcer and bone, showing severe osteomyelitis and intraosseous filamentous organisms, morphologically consistent with Actinomyces spp. The boy received long-term antibiotics with response to treatment. Actinomycosis has rarely been reported in the cervical vertebrae of paediatric patients. This should be considered as a differential diagnosis for such a presentation as prompt antibiotic treatment may be lifesaving.

Figure 1

(A) Sagittal CT image of the cervical spine demonstrating extensive erosive changes of the anterior C1 arch and the anterior odontoid process (white star). There is adjacent ulceration of the dorsal oropharynx with adjacent soft tissue swelling (white arrow). (B) Axial CT image demonstrating irregular lucencies through the lateral masses of the C1, concerning for pathological fractures (white arrows).

Figure 2

Sagittal T2-weighted MRIs demonstrating prevertebral soft tissue oedema (white arrow) and bone marrow oedema involving the C1 and the odontoid process (white arrow). No evidence of epidural disease is seen.

Figure 3

(A) Bone fragment showing severe acute osteomyelitis, osteonecrosis and organisms (H&E stain20). (B) Aggregate of filamentous organisms morphologically consistent with Actinomyces species (H&E stain ×200).

Figure 4

Actinomyces colonies highlighted by Gomori methenamine silver stain (left) with negative acid-fast bacilli stain (right).