A thirty-two-year-old adult male presents with a chronic suppurative lesion on the angle of the jaw. Microscopic examination shows small abscesses immediately beneath
the epidermis with moderate growth of epithelial cords. In the abscess, there are oval, unicellular organisms measuring 20 µm in diameter and having a thick, double-refractive cell wall and cytoplasm containing refractive granules and vacuoles. Which of the following is the most likely diagnosis?
Blastomycosis is a relatively uncommon disease caused by the dimorphic fungus known as Blastomyces dermatitidis. 
These organisms are 8 to 20 µm in diameter. They are characterized by a doubly refractile cell wall and a broad attachment between the budding daughter cell and the parent cell. 
Ref: Neville's  oral and maxillofacial pathology 4th edition page 204
Blastomycosis
Foreign body reaction
Syphilis
Tuberculosis