The aim of this report is to document a very rare case of Blastomycosis dermatitidis mastoiditis with extension into the retromastoid soft tissue and surrounding muscle. Blastomycosis dermatitidis is a dimorphic fungus of endemic areas which classically infiltrates the lungs; however, dissemination presenting as otomastoiditis is exceedingly rare. The patient was an immunocompetent 27-year-old male with no significant preexisting health conditions. He had significant work exposure to dust and soil and was referred to our department for evaluation of otalgia with headaches, hearing loss, and intermittent facial paralysis. Initially, the extent of the infection was unknown. Based on extensive disease on magnetic resonance imaging, the patient was scheduled for urgent tympanoplasty and mastoidectomy. Postoperative treatment with itraconazole resolved any further manifestations and halted further soft tissue invasion. It is important to consider uncommon fungal infections in the workup of persistent otalgia, especially when presenting with facial paralysis and a history of environmental exposure to soil and dust. This type of infection should be considered regardless of immunodeficiency status. Early detection may prevent hearing loss and local invasion into surrounding structures.
Keywords: fungal infections; infectious diseases; otitis; otolaryngology; otology; skull base.