Phaeohyphomycotic pseudotumor of the right elbow caused by T
A 49-year-old immunocompetent male with an unremarkable medical history presented with a slow-growing painless soft-tissue mass on the right elbow after long-standing (4 years) olecranon bursitis. He was otherwise in good general health.

On examination, he had an asymptomatic 4-cm nodule on the posterior aspect of the right elbow with no overlying skin changes, warmth, or impairment in a range of motion. The remaining skin exam was unremarkable, with no lymphadenopathy. He was HIV-negative, with otherwise normal complete blood count, blood chemistries, and CD4 count. He was originally referred by rheumatology who had treated him for olecranon bursitis prior to presentation at our clinic. Analysis of aspirated synovial fluid revealed brownish fluid with pigmented fungal hyphae. Genetic sequencing and culture revealed T. grisea. Imaging studies did not reveal dissemination, and the patient was initiated on itraconazole (100 mg twice daily) for 12 months per recommendation by infectious disease.

Upon completion of therapy, the patient returned, complaining of a recurrent mass, which developed at the location of prior bursitis. Excisional biopsy demonstrated a mixed granulomatous infiltrate consisting of giant cells, lymphocytes, and neutrophils. Special stains demonstrated septate fungal hyphae with the production of melanin. Growth of light gray colonies with central dark gray areas were obtained on Sabouraud dextrose agar, with no species-specific conidia or toruloid mycelia. Fungal ribosomal internal transcribed spacer region DNA sequencing was conducted using RipSeq Single software (Pathogenomix), which provided a 100% match to several CBS reference strains deposited in GenBank (PMID: 25737597). The organism was identified as T. grisea. Per infectious disease, the itraconazole regimen was continued for 3 more months after excision of the lesion. The patient has remained without recurrence for 3 years since surgery.