Actinomycosis — MFDS Part 1 MCQ

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ModerateMicrobiologyActinomycosisMFDS Part 1

A patient develops a slowly progressive, firm mandibular swelling with multiple draining sinuses following a dental extraction. Which finding in the sinus discharge is classically associated with cervicofacial actinomycosis?

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Correct answer: C — Sulphur granules

The correct answer is C: sulphur granules. Cervicofacial actinomycosis classically causes a chronic, firm or “woody” swelling with abscesses and draining sinuses. The discharge may contain yellow sulphur granules, representing colonies of branching, Gram-positive, non-acid-fast Actinomyces organisms rather than elemental sulphur. These granules are characteristic and diagnostically helpful, but they are not strictly pathognomonic because similar granules can occur in other infections. Fungal hyphae indicate a mycosis, acid-fast bacilli suggest mycobacterial infection, and Gram-positive cocci in clusters are typical of staphylococci. Clue cells are vaginal epithelial cells associated with bacterial vaginosis and have no relevance to a jaw infection.

Reference: Boyanova L, Kolarov R, Mateva L, et al. Actinomycosis: a frequently forgotten disease. Future Microbiology. 2015;10(4):613–628. https://pubmed.ncbi.nlm.nih.gov/25865197/