Miguel Gomez

A 60-year-old gentleman presented to a clinic with a large ulceration over his left tibia. The wound was friable, erythematous, and purulent, with necrotic involvement of the tibial tendon sheath. He reports that the lesion started 15 years ago and worsened after surgical debridement 10 years ago. High-dose prednisone helped in the past, but other medications have been of no help. Recently, the patient developed intense pain with occasional fevers, chills, and night sweats. He has type 2 diabetes mellitus, but denies any history of bowel difficulties, hepatitis, or arthralgias. What is your diagnosis?