A 73-year-old Caucasian male with past medical history of Pott's disease as a child, osteoarthritis of the right knee, and a right Baker's cyst presented to the Emergency department with complaints of worsening leg pain for two days and confusion for one day. At presentation, the patient was tachycardic. All other vital signs were within normal limits. His review of systems was remarkable for chronic knee pain for the last two years and right leg pain for the last three months and decreased appetite and weight loss over the course of four months. On physical examination, the patient was in moderate distress. He was alert and oriented to time, place, and person but had poor concentration. On musculoskeletal exam there was a diffuse area of swelling on the right lower extremity which was extremely tender to touch with minimal warmth and erythema. This was located posteromedially involving the calf and medial aspect of the leg. Knee joint was nonswollen, nontender, and without any erythema or warmth (Figure 1). Laboratory data revealed leucocyte count 14.6 k/cumm, Hemoglobin 10.2 mg/dL, and hematocrit 30.4%. HIV testing was negative. His metabolic panel showed hyponatremia, 124 mEq, but was otherwise unremarkable. Leg MRI was performed. This showed a large heterogeneous fluid collection involving the subcutaneous soft tissues of the posterior medial right lower extremity measuring approximately 21.1 x 7.2 x 8.5 cm with marked mass effect on the gastrocnemius muscle. Heterogeneity of the distal femur including the femoral condyles, tibial plateau, and proximal fibular head was also visualized suggesting possible osteomyelitis as well (Figure 2). The patient underwent surgical resection of the left Baker's cyst. Intraoperative findings included a thick, boggy synovium with dull and dusky appearing cartilage. Tissue and fluid stain revealed acid fast bacillus (AFB) in one of two samples which was later identified as MTB. On pathologic section, a granulomatous reaction with giant cells was present. The patient was placed in airborne isolation and a workup for dissemination was pursued. Respiratory samples also had AFB identified on initial acid fast staining. Chest CT showed multiple apical cavitary lesions and nodular infiltrates with tree in bud opacities in the apices and right lower lobe. Acute kyphotic deformity of the upper thoracic spine with loss of vertebral body height, vertebral body fusion, posterior element fusion, and kyphosis consistent with the patient's known history of Potts disease was also seen in chest CT. Due to worsening mental status, a diagnostic lumbar puncture was also performed. CSF analysis showed 1 red blood cell/UL, 151 white blood cells/UL, 64% neutrophils, protein 1668 mg/dL, and glucose of 8 mg/dL. CSF polymerase chain reaction tested positive for MTB. Testing for HIV, Hepatitis B, and C was negative. Treatment with rifampicin, ethambutol, isoniazid, pyrazinamide, and dexamethasone was started. During the course of therapy, patient developed pneumonia and hypoxic respiratory failure requiring intubation. Family chose to proceed with comfort measures only and the patient passed away due to septic shock.